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This is the Top Page of the AIPS HOMEPAGE
updated at 21:00 p.m. on July 31, 2021 ( Japan Time )
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"Story of Pinned Photodiode" by Yoshiaki Daimon Hagiwara (AIPS)

Hagiwara_at_Sony_invented_in_1975_and_developed_Pinned_Photodiode_in_1978.pdf

Publication_and_PDF_file_Yoshiaki_Hagiwara.html


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A000 Truth_about_Invention_of_Pineed_Photodiode_by_Yoshiaki_Hagiwara.pdf
A001 Hagiwara_invented_Pinned_Photodiode_in_1975.html
A002 Hagiwara_invented_Pinned_Photodiode_in_1975.html
A003 Slides_of_Sony_Atsugi_Tech_Talk_2020_07_10
A004 IEEE_3DIC2019_Conference_Paper_on_Multichip_CMOS_Image_Sensor_Structurefor_Flash_Image_Acquisition
A005 EDTM2020_Conference_Paper_ID_3C4_by_Yoshiaki_Hagiwara(html)
A006 Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes_by_Yoshiaki_Hagiwara_IJSSAM_Paper_20210616.pdf
A007 Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes_by_Hagiwara.html
A008 Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes_by_Hagiwara.pdf
A009 How_Sony_won_the_Farichild_Patent_War.pdf
A010 Hagiwara_invented_PPD_and_Sony_HAD_in_1975.pdf
A011 Hagiwara_invented_PPD_and_Sony_HAD_in_1975.html
A012 Introduction_to_JPA2020_131313_PNP_Double_Junction_Solar_Cell_by_Hagiwara.pdf
A013 Japanese_Patent_Application_JPA2020_131313_PNP_Double_Junction_Solar_Cell_by_Hagiwara.pdf
A014 Proposal_of_Pinned_Photodiode_type_Solar_Cell_2020_09_28.html
A015 Hagiwara_Patents(JPA)_and_Published_Papers_PDF_Files(html)
A016 Sony_acknowledged_that_Hagiwara_invented_PPD_with_VOD_for_Electric_Shutter_Function
A017 Semiconductor_History_Museum_of_Japan_also_supoorts_Hagiwara_1975_PPD_invention
A018 Hagiwara_drew_the_Triple_Junction_Type_Pinned_Photodiode_in_his_1975_Lab_Note

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On Nov 13, 2021, a Japanese Newspaper by Sangyou Times wrote an aticle on Hagiwara Profile.
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A019 https://www.sangyo-times.jp/article.aspx?ID=5331
A020 Future_of_Image_Sensors_and_Solar_Cells.pdf
A021 Future_of_Image_Sensors_and_Solar_Cells.html


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+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
The Evidence that Yoshiaki Hagiwara is the inventor of Pinned Photodiode is given below:
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
A022 Definition_of_Pinned_Photodiode.pdf


********************* A023 E-Tegami of Tomie Hagiwara*********************



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A024 Community_Cafe_Ogino,Atsugi-city,Kanagawa



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A025 WAKA ( Japanese Short Poem )
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A026 https://www.sony.com/ja/SonyInfo/News/notice/20200626/


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A027
Society of Semiconductor Industry Specialists (SSIS)


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A028 SSIS_Education_GP_Activity_PR_MP4_01

A029 SSIS_Education_GP_Activity_PR_MP4_02

A030 SSIS_Education_GP_Activity_PR_MP4_03

A031 Image_Sensor_Introduction_MP4_Video_for_AIPS_Robotics_by_Yoshiaki_Hagiwara

A032 Image_Sensor_Story_Hagiwara_html ( Members Only )

A033 SSIS_Education_Activity ( Members Only )

A034 Story_of_Sony_Development_Efforts_on_Image_Sensors_by_Yoshiyuki_Kawana

A035 >Reporting_ISSCC2006_by_Yoshiaki_Hagiwara_May_2006


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A036 (Essay) Candy in the Heart by Yoshiaki Hagiwara



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A037 Pinned_Photodiode_invented_by_Hagiwara_in_1975_with_C-Coding Program (pdf)


A038 Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes_Memo_2021_05_11.pdf



--P011-- The_Pinned_Photodiode_with_VOD_function_by_Hagiwara_1975.jpg





--P012-- JPA1975_127647_Pinned_Photodiode_invented_by_Hagiwara_in_1975.jpg





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History_of_Invention_and_Development_of_Pinned_Photodiode.pdf


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++++++++++++++++++++++++++++++++++++++++++++++++++++++++
The Evidence that Yoshiaki Hagiwara at Sony Invented Pinned Photodiode in 1975.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Dear Sir


Your honest, free and neutral opinion on the history of invention
and development efforts of image sensors is very important.

The truth should be revealed to all of the people in the world.
You are just one of them. But each one is very, very important.


I summarized my point of view on the history of the invention and the development efforts
of Pinned Photodiode. When I jointed SONY in 1975 after receiving PhD from Caltech, Sony
people understood the importance of the CCD complete charge transfer operation and the
excellent feature of no image lag in the CCD/MOS dynamic photo capacitors. However
Sony was suffering the yield problem due to the strong surface electric field and the
poor short wave blue light sensitivity since the CCD/MOS dynamic photo capacitors have
the metallic polysilicon electrodes which do not pass the short wave blue light. As you may
know the short wave blue light cannot penetrate more than 0.1 micro meter in depth in
the silicon crystal. The double dynamic photo transistor and the triple junction photo
thyristor were the answers which do not have the surface electric field nor the metallic
electrodes. I applied Japanese patents JP1975-127646, JP1975-127647 and JP1975-134985.
The proposed photodiodes were intended to be applied to the interline CCD image sensors
as explained in my Japanese 1975 patents . I developed the P+NP double junction type photodiode
in 1978 used it in the FT CCD image sensors and reported at SSDM1978 conference in Tokyo.
After that , SONY kept silent since it was a top secrete project in SONY. SONY took more than
8 years to develop and make the passport size portable video cameras with the P+NPN triple
junction type photodiode with the in-pixel overflow drain with the complete electrical
shutter function for action pictures. Sony was only the maker who could produce the camera.

I summarized the details in the site shown below. The problem was that I forgot completely
myself the details of my 1975 inventions since I was busy since 1980 in developing the system
LSI chip sets such as for the SONY AIBO robots and the PS2 and PS3 Play Station Game Machines.

I uploaded here the complete form of my point of view on the PPD invention and development efforts.

I wish people would kindly read this for me and let me know what they think about this.

I am not asking your opinion on the patent issues. Patent issues
were already settled and no problems. Sony is now enjoying the
image sensor business being protected by Hagiwara 1975 Pinned
Photodiode patents. KODAK , NEC and Fairchild also did apply
similar PPD patents. But they were all applied later than 1975.

I am asking your opinion on who is the inventor and who
first developed Pinned Photodiode and reported in the
international technical conference.

These facts are important for the history of image sensors and
have very important meanings as back ground information
and for educational purpose for young generations who
may have interest in image sensors and its history.

The SSDM1978 Conference held in Tokyo in 1978 is also an
international conference but with a very limited number.

The published SSDM1978 conference journal paper is not widely accessed.

But Albert Theuwissen found my SSDM1978 paper after 18 years
and quoted my original 1978 PPD work in his IEEE2006 paper.

<001>P1978_SSDM1978_Paper_quoted_in_2006_paper.jpg




Albert Theuwissen did not emphasize the complete charge transfer feature of
Pinned Photodiode since CCD has already the complete charge transfer feature.

The complete charge transfer feature was nothing new.

The importance of Pinned Photodiode were

(1) The excellent short wave blue sensitivity and

(2) the Low Surface Dark Current.

Firstly, since CCD has the metal electrode, it has a poor short wave
blue light sensitivity.

Secondly, the CCD/MOS dynamic photo capacitor has a strong surface electric field
which induces the undesired surface dark current.

However, Albert Theuwissen apparently and SONY( Hagiwara) already understood
the feature of the complete charge Transfer mode of Pinned Photodiode.


NEC IEDM1982 paper by Teranishi reported the importance of the image lag feature
of Buried Photodiode. But Buried Photodiode is not always Pinned Photodiode.

NEC IEDM1982 paper by Teranishi also reported the serious undesired image lag
feature of the NEC1982 Buried Photodiode in the IEDM1982 paper. Any photodiode
with image lag feature is not Pinned Photodiode according to the Fossum Paper.

Hence NEC IEDM1982 paper was not Pinned Photodiode by definition.

<002>NEC_IEDM1982_Paper_was_not_Pinned_Photodiode_by_definition(jpg)




Many people were misled by Fossum paper.

<003>Many_people_were_misled_by_Fossum paper(jpg)





The Difference of Pinned Photodiode and Buried Photodiode was well explained in
the article which says ,"...acknowledge Hagiwara-san's contribution.It has long
been incorrectly attributed to Teranishi and to Fossum (in CMOS image sensors)"


<004>Difference-between-Buried-Photodiode-and-Pinned-Photodiode(html)



"A pinned PD is designed to have the collection region deplete out when reset.
AS the PD depletes it becomes disconnected from the readout circuit and
if designed properly will drain all charge out of the collection region
(accomplishing complete charge transfer). An interesting side effect is
that the capacitance of the PD drops to effectively zero and therefore
the KTC noise qn=sqrt(KTC) also goes to zero. When you design the depletion
of the PD to deplete at a certain voltage you are pinning that PD to that
voltage. That is where the term comes from. I've edited this Answer to
acknowledge Hagiwara-san's contribution. It has long been incorrectly
attributed to Teranishi and to Fossum (in CMOS image sensors)"

Actually the in-pixel active sensor was first invented and reported
in 1968 by Peter Noble at Plessy in England UK before Fossum work in 1990.


These truth was not well understood widely.

Teranishi and Fossum are well received to the world for their contributions.

But they never quoted Hagiwara and Noble previous old works.

The people misunderstood that Teranishi and Fossum were
the first inventors and the first developers.

Patent issues are settled and now Sony enjoy the image
Sensor business with advantage over KODAK, NEC ,
Fairchild and other competing companies. Sony has
Hole Accumulation Diode (HAD) which is identical to
Pinned Photodiode in the world wide business with
more than 60 to 70 % share of image sensor devices.

Now the KODAK-named Pinned Photodiode reported in IEDM1984
is now considered as the invention by Teranishi at NEC in 1980,
according to the paper "A Review of the Pinned Photodiode
for CCD and CMOS Image Sensors" by E.Fossum. This Fossum
paper was attacking Hagiwara 1975 patent and SSDM1978
paper with misleading descriptions on no image lag issue.

Hagiwara 1975 patent and SSDM1978 paper did report the
complete charge transfer operation and showed the empty
potential well profile which are signs of no image lag feature.


The truth is that Hagiwara proposed 1975 the now-called
Pinned Photodiode in form of the double PNP and triple PNPN
junction dynamic photodiodes originally.


The double PNP and triple PNPN junction dynamic photodiodes
in 1975 and reported the double PNP junction dynamic
photodiode in Hagiwara SSDM1978 paper.

The patent issues were settled and no problems.
In the secret patent disputes and the public US courts ,
Fairchild, KODAK, NEC in the past attacked Sony on the
basic Pinned Photodiode patents but they were all not
successful. NEC gave up image sensor business and
Fairchild and KODAK made friendly technical agreements
with Sony now. I am not asking about the patent issue.

I need to hear your personal opinion on the historical background
of the invention and the Innovation efforts of Pinned Photodiode.

The truth should be revealed to all of the people in the world.

You are just one of them. But each one is very, very important to me.

Fossum paper claims that Hagiwara JPA1975-134984 and
Hagiwara 1978 paper did not describe the image lag feature.

I believe Fossum misunderstood my 1975 patent and 1978 paper.

Hagiwara JPA1975-134984 showed an empty potential of
the buried N storage region of the double junction PNP
dynamic photo transistor structure with the emitter and
the collector terminals both pinned, which is identical to
Pinned Photodiode. As you know the empty potential well
implies the complete charge transfer operation which results
in the excellent feature of no image lag in video camera.

Hagiwara SSDM1978 paper reported the output wave forms of
the image sensor using the double PNP junction photodiode
with the pinned P+ surface region directly connected to
the adjacent P+ channel stops, which is also identical to
the definition of Pinned Photodiode. The output wave forms
showed a very low total surface dark current of less than 3%
and the complete charge transfer efficiency of more than 99.995%
which implies the excellent feature of no image lag.

My work was cited in "A Review of the Pinned Photodiode for CCD
and CMOS Image Sensors" by E.Fossum. Actually E.Fossum was
attacking my 1975 PPD patent and SSDM1978 PPD paper.

Please kindly read carefully Fossum paper. Fossum was not telling
the truth about Hagiwara 1975-134985 patent and Hagiwara
SSDM 1978 paper. Fossum paper was misleading and had a wrong
conclusion.

I have reported the image lag feature of the complete charge
transfer operation both in my 1975 PPD patent and SSDM1978
PPD paper. Fossum did not read carefully or does not understand
the details of my 1975 PPD patent and SSDM1978 PPD paper.

The truth should be revealed to all of the people in the world.
You are just one of them. But each one is very, very important to me.

I would like to hear your personal opinion on this.


For your information, Sony wrote an article
regarding the original invention of Pinned Photodiode
in the Sony Official Homepage:

<005>https://www.sony.com/en/SonyInfo/News/notice/20200626/


And Sony explained and claimed,

"In 1975, Sony invented a CCD image sensor that adopted a back-illuminated N+NP+N junction type
and an N+NP+NP junction type Pinned Photodiode (PPD) (Japanese patent application number
1975-127646, 1975-127647 Yoshiaki Hagiwara). In the same year, inspired by such structure,
Sony invented a PNP junction type PPD with VOD (vertical overflow drain) function (Japanese
Patent No. 1215101 Yoshiaki Hagiwara). After that, Sony succeeded in making a principle prototype
of a frame transfer CCD image sensor that adopted the PNP junction type PPD technology, having a
high-impurity-concentration P+ channel stop region formed near a light receiving section by ion
implantation technology for the first time in the world, and its technical paper was presented
at the academic conference, SSDM 1978 (Y. Hagiwara, M. Abe, and C. Okada, "A 380H x 488V CCD
imager with narrow channel transfer gates", Proc. The 10th Conference on Solid State Devices,
Tokyo, (1978)). In 1980, Sony succeeded in making a camera integrated VTR which incorporated
a one-chip frame transfer CCD image sensor that adopted the PNP junction type PPD. President
Iwama in Tokyo, Chairperson Morita in New York, at the time held a press conference respectively
on the same day, which surprised the world. In 1987, Sony succeeded in developing a 8 mm video
camcorder that adopted, for the first time in the world, the interline transfer CCD image sensor,
which incorporated "PPD having a high-impurity-concentration P+ channel stop region formed near
the light receiving section by ion implantation technology" with VOD function, and became the
pioneer of the video camera market. The PPD technology that has been nurtured through such a
long history is still used in back-illuminated CMOS image sensors."


The Society of Semiconductor Industry Specialists (SSIS) of Japan
Society of Semiconductor Industry Specialists (ssis.or.jp)
also wrote an article regarding the original invention of Pinned Photodiode
on the SSIS official Homepage:

<006>https://www.shmj.or.jp/english/pdf/dis/exhibi1005E.pdf


The Society of Semiconductor Industry Specialists (SSIS) of Japan explained
and claimed in details as

"The Pinned Photodiode is a photodiode in which the entire N layer is
covered with a P layer. The part of the P layer on the light incident
surface is heavily doped P+. Kodak named this structure Pinned Photodiode
in 1984 because the P+ surface of the light incident surface was pinned
to the substrate potential.

This device has features such as high light sensitivity, wide dynamic range,
image lag free, much smaller dark current due to reduced influence of GR center
on the light receiving surface, and no white scars.

In 1975, Sony proposed using a PNP transistor as the photodetector [3].
By providing a P+ layer (emitter) for the light incident section,
the sensor electrode that covers the entire light receiving surface of
the photodiode can be eliminated to improve the light sensitivity greatly.
It was a basic proposal for a pinned photodiode with a P+ layer on the surface
of the light receiving part."

The reference [3] is my original Japanese Patent on Pinned Photodiode.
The photodiode structure was originally defined as the double PNP dynamic photo transistor
and the triple junction PNPN dynamic photo thyristor in my patent application Jp1975-134985.

[3] Y. Hagiwara, Japanese Patent JP1975-134985

<007>JP1975-134985_Patent_on_the_PNP_Double_Junction_Pinned_Photodiode_on_Nsub(pdf)


The structure was later called as Buried Photodiode by NEC in 1982, Pinned Photodiode by KODAK in 1984,
and as the Hole Accumulation Diode (HAD) by Sony in 1987.

But all of them are identical to my 1975 invention.

I believe I am the inventor of Pinned Photodiode in 1975 and developed Pinned Photodiode in 1978.

<008>P1978_SSDM1978_Paper_on_the_P+PN_Double_Junction_Pinned_Photodiode_by_Hagiwara(pdf)

And Sony built the video movie camera used Pinned Photodiode
in the one chip NTSC full size Frame Transfer CCD image sensor in 1980

The details of my works are explained in the following publications.

Would you kindly read my papers and let me know your personal opinion on
who really invented Pinned Photodiode and developed it for the first time in the world ?


<009>P2021_IJSSA2021_Paper_on_Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes(pdf)


++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Paper Accepted with a minor revision. Reviews' Comments:
++++++++++++++++++++++++++++++++++++++++++++++++++++++++

"This is a comprehensive paper, well designed, performed and written.
The logicality of this paper is quite good and the main body provides
sufficient information. The study abstract is concise and clearly presented,
and the figures in the article have well illustrated the study. Meanwhile,
the author gives a comprehensive description in conclusion.
This is a very instructive research. It is suggested that recommendations
for follow-up or future work on this topic should be made."

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
List of Related Published Papers on Pinned Photodiode
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++

<010>P1978_SSDM1978_Paper_on_the_P+PN_Double_Junction_Pinned_Photodiode_by_Hagiwara(pdf)


<011>P1979_CCD79_in_Edinburgh_Invited_Paper_by_Hagiwara.pdf


<012>P1996_IEEE_Paper_on_Pinned_Photodidoe_used_in_Sony_1980_FT_CCD_Image_Sensor.pdf


<013>P2001_ESSCIRC2001_Invited_Talk_on_Micro_Electronics_for_Home_Entertainmen_by_Hagiwara.pdf


<014>P2008_ESSCIRC2008_Invited_Talk_on_SOI_Design_in_Cell_Processo_and_Beyond_by_Hagiwara.pdf


<015>P2013_ISSCC2013_Invited_Panel_Talk_on_the_PNPN_Diode_in_Future_Linear_Motor_Cars_and_in_Modern Imager_by_Hagiwara.pdf


<016>P2017_CoolChips_Invited_Pane_Talk_on_Cool_chips_for_the_next_decade_by_Hagiwara_20l170419(pdf)


<017>P2019_3DIC2019_Paper_on_Multichip_CMOS_Image_Sensor_Structure_for_Flash_Image_Acquisition(pdf)


<018>P2020_EDTM2020_Paper_ID_3C4_on_Simulation_and_Device_Characterization_of_Pinned_Photodiode(pdf)


<019>P2021_IJSSA2021_Paper_on_Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes(pdf)


++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Unfortunately these Japanese Patent Applications of mine shown below were
written only in Japanese language and were never disclosed in details to
the English Speaking Community.

<020>JP1975-127646_NPNP_triple_junction_Pinned_Photodiode_Patent_32_pages.pdf


<021>JP1975-127647_NPN_double_junction_Pinned_Photodiode_Patent_22_pages.pdf


<022>JP1975-134985_PNP_double_junction_Pinned_Photodiode_on_Nsub_Patent_7_pages.pdf


<023>JP1977-126885_Elecric_Shutter_Clocking_Scheme_by_OFD_Punch_Thru_Action_13_pages.pdf



Very Sincerely

Yoshiaki Hagiwara

hagiwara-yoshiaki@aiplab.com

<024>http://www.aiplab.com



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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

*********************************************************************
hagiwara-yoshiaki@aiplab.com for my activity at http://www.aiplab.com/
hagiwara@ssis.or.jp for my activity at http://www.ssis.or.jp/en/index.html
*********************************************************************





--P013-- JP1975_127647_Barrier_Potential_Pinned_Surface_Hole_Accmulation_Region.jpg





--P014-- Problems_of_Conventional_Single_Junction_type_Solar_Cells.jpg





--P015-- Problem_of_Single_Junction_type_Solar_Cells.jpg





--P016-- JPA1975_127647_Pinned_Photodiode_with_Back_Light_Illumination.jpg





--P017-- JPA2020_131313_Pinned_Photodiode_type_Solar_Cell.jpg



P015 JPA2020_131313_PNP_Double_Junction_Type_Solar_Cell.pdf


--P018-- Barrier_Width_Wbar_of_Double_Gaussian_Doping_Profile.jpg





--P019-- JPA1975_127647_and_JPA1975_134985_Pinned_Photodiode_used_for_Solar_Cell.jpg





--P020-- JPA2020_131313_The_PNP_double_junction_type_Solar_Cell_by_Yoshiaki_Hagiwara_2020.jpg





--P021-- JPA2020_131313_Double_Junction_type_Pinned_Photodiode_Solar_Cell.jpg





--P022-- JPA2020_131313_PNP_Double_Junction_Type_Solar_Cell.jpg





--P023-- Pinned_and_Buried_Photodiode_type_Solar_Cell_invented_by_Hagiwara_in_2020.jpg





--P024-- JPA2020_131313_Pinned_Photodiode_Solar_Cell_invented_by_Hagiwara_in_2020.jpg





--P025-- PNP_Double_Junction_type_CCD_MOS_Dynamic_Photo_Capacitor.jpg




A038A
Caltech_1975_PhD_Thesis_by_Yoshiaki_Daimon_Hagihara(Hagiwara).pdf


--P026--Polysilicon_and_Meta_Overlappin_Gat_Burie_Channel_CCD.jpg



A038B
BCCD_1D_Analysis_Depletion Approximation.pdf


A038C EDTM2020 Paper
EDTM2020(html)



A039 https://www.sony.com/ja/SonyInfo/News/notice/20200626/


A040 https://www.sony.com/en/SonyInfo/News/notice/20200626/



--P027A--Pinned_Photodiode_used_in_Back_light_CMOS_Image_Sensor.jpg





--P027B--Hagiwara_proposed_Pinned_Photodiode_in_1975_JSHM.jpg





--P027C--JP1977_837_is_not_Pinned_Photodiode.jpg





--P027D--Difference_of_Buried_Photodiode_and_Pinned_Photodiode_2.jpg





--P027E--Difference_of_Buried_Photodiode_and_Pinned_Photodiode.jpg





--P027F--NEC1980_Patent_Photodiode_is_not_Pinned_Photodiode.jpg




A041 Invention_of_Pinned_Photodiode_Innovation_100.pdf



--P027G--Buried_Photodiode_with_Floating_Surface_of_Serious_Image_Lag_Problem.jpg





--P027H--Difference_of_Pinned_Photodiode_and_Buried_Photodiode_2021.jpg





--P027I--image3B_Hagiwara_at_Sony_invented_Pinned_Photodiode_in_1975.jpg





--P027J--image3D_Hagiwara_at_Sony_invented_Pinned_Photodiode_in_1975.jp





--P027K--P1978_SSDM1978_Paper_quoted_in_2006_paper.jp




A042 E-mail_Communication_on_Sony_Loral_Patent_War_1996.pdf



A043A Artificial_Intelligent_Image_Sensor_by_Yoshiaki_Hagiwara(html)

A043B Image_Sensor_Story_by_Yoshiaki_Hagiwara(html)
A044 Hagiwara_invented_PPD_and_Sony_HAD_in_1975.pdf

A045 The_First_Pinned_Photodiode_was_invented_in_1975_by_Yoshiaki_Hagiwar_at_Sony.pdf


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

AIPS is the non-profit private organizaion (NPPO)

dedicated to produce scientific guide books and educational and introductory materials

devoted for the develpments of the Human Friendly Artificial Intelligent Partner System (AIPS),

AI Real Time Pattern Recognition Processors and Robotics Intelligent Vision Systems.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A046 Hagiwara Yoshiaki Lecture Notes for AIPS Robotics

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++



--P028--



Yoshiaki Hagiwara was invited to talk about his dreams

in the international technical conferences.



A047 https://imagesensors.org/

A048 P1979_CCD79_in_Edinburgh_1979.pdf

A049 https://www.esscirc-essderc2021.org/

A050 http://www.aiplab.com/P2001_ESSCIRC2001.pdf

A051 http://www.aiplab.com/P2008_ESSCIRC2008Hagiwara.pdf

A052 http://isscc.org/


A053 P2013_ISSCC2013PanelTalk.pdf

A054 https://www.coolchips.org/


A055 P2017_CoolChipsPanel170419.pdf


Yoshiaki Hagiwara also wrote papers about his works and dreams.


A056 P1996_Pinned_Photodidoe_used_in_Sony_1980_FT_CCD_Image_Sensor.pdf 

A057 P2019_3DIC2019Paper_on_3D_Pinned_Photodiode.pdf 

A058 P2020_EDTM2020_PaperID_3C4_by_Hagiwara.pdf 

A059 EDTM2020(html)>


These works were based on the following Japanese Patent Applications

that was never been desiclosed in details until recently

because of Hagiwara himself neglecting to appeal its importance.


A060 JP1975-127646.pdf 

A061 JP1975-127647.pdf 

A062 JP1975-134985.pdf 

A063 JP1977-126885.pdf


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++




++++++++++++++++++++++++++++++++++++++++++++++++++++
On Nov 13, 2021, a Japanese Newspaper by Sangyou Times
wrote an aticle introducing Hagiwara.
++++++++++++++++++++++++++++++++++++++++++++++++++++

A064 Future_of_Image_Sensors_and_Solar_Cells.pdf

A065 Future_of_Image_Sensors_and_Solar_Cells.html
+++++++++++++++++++++++++++++++++++++++++++++

A066 Sony_acknowledged_that_Hagiwara_invented_PPD_with_VOD_for_Electric_Shutter_Function

A067 Semiconductor_History_Museum_of_Japan_also_supoorts_Hagiwara_1975_PPD_invention

A068 Hagiwara_drew_the_Triple_Junction_Type_Pinned_Photodiode_in_his_1975_Lab_Note

+++++++++++++++++++++++++++++++++++++++++++++


*****************************************
AIPS Library
*****************************************

Yoshiaki Hagiwara wrote a book on
"the World of Artificial Intelligent Digital Circuits",
which is important and needed to built
the intelligent image sensor systems.

ISBM978-4-88359-339-2
Hard Cover, 460 page,
\ 9000 Japanese Yen + tax



--P029--


If you are interestied in the book, Please visit

A069 https://www.seizansha.co.jp/ISBN/ISBN978-4-88359-339-2.html

A070 https://www.seizansha.co.jp/

*****************************
Basic Questions on Image Sensors
******************************



--P030A--


--P030B--


--P030C--




++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A071 Gate Way to AIPS Library

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A072 index_001_Enjoy_the_World_of_Hagiwara_Tomie_E_Tegami_Gallery.html

A073 index_002_Enjoy_the_World_of_Hagiwara_Yoshiaki_Talks_and_Photo_Desk.html

A074 index_003_Enjoy_the_World_of_Japanese_Short_Poem.html

A075 index_004_Enjoy_the_World_of_Korean_Conversation.html

A076 index_005_Enjoy_the_World_of_English_Conversation.html

A077 index_006_Enjoy_the_World_of_Mathematics_Physics_and_Relativiry_Theory.html

A078 index_007_Enjoy_the_World_of_Quantum_Mechanics_and_Semiconductor_Device_Physics.html

A079 index_008_Enjoy_the_World_of_Artificial_Intelligent_Partner_System_AIPS_Digital_Circuits.html

A080 index_009_Enjoy_the_World_of_Solid_State_Image_Sensors_and_PPD_Solar_Cells.html

A081 index_010_Hagiwara_is_the_true_inventor_of_Pinned_Photodiode_PPD_and_Sony_HAD.html


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
A082
Hagiwara_invented_PPD_and_Sony_HAD_in_1975.pdf


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A082A 001_Hagiwara_invented_PPD_and_Sony_HAD_in_1975.pdf

A083 002_Image_Sensor_Story_by_Hagiwara.pdf

A084 003_Future_of_Image_Sensors_and_Solar_Cells.pdf

A085 004_The_First_Pinned_Photodiode_was_invented_in_1975_by_Yoshiaki_Hagiwar_at_Sony.pdf

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

What is the difference of Pinned Photodiode(PPD) and Buried Photodiode(BPD) ?

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Buried Photodiode (BPD) was invented by Yoshiaki Hagiwara at sony in 1975
as a double junction type PNP photodiode.

A086 JP1975-127646.pdf
A087 JP1975-127647.pdf
A088 JP1975-134985.pdf

However, Buried Photodiode(BPD) is not always Pinned Photodiode (PPD).

Buried Photodiode(BPD) may not have the Pinned surface p region.

Buried Photodiode(BPD) may have the serious image lag problem.

Buried Photodiode(BPD) may have the serious surface dark curent

when the surface is completely depleted and has the surface strong electric field


Pinned Photodiode (PPD) was also invented by Yoshiaki Hagiwara at Sony in 1975
in JPA 1975-127646 as a double junction type N+N-P+NP-P Buried Photodiode
and in JPA 1975-127647 as a triple junction type N+N-P+N Buried Photodiode
with the Pinned Surface N+N barrier electric field in the surface electron accumulation region
of the excellent short wave blue light sensitivity,
the very low surface dark current noise, and
the complete charge transfer capability of no image lag feature.

A086 JP1975-127646.pdf

A087 JP1975-127647.pdf

A triple junction type P+NPNsub Pinned Photodiode,
which is a double junction type P+NP Pinned Photodiode in the N type Silicon substrate Nsub,
was also invented in JPA 1975-134985 by Yoshiaki Hagiwara at Sony in 1975
with the built-in vertical overflow drain (VOD) capability.

A088 JP1975-134985.pdf

Electrical Shutter Function Clocking Scheme
of controling the punch thru voltage of the built-in verical overflow drain (VOD)
was also invented in JPA 1975-126885 by Yoshiaki Hagiwara at Sony in 1977
and was applied in the triple junction type P+NPNsub Pinned Photodiode
which was named in 1987 as Hole Accumulation Diode(HAD) by Sony Hamazaki Team .

A089 JP1977-126885.pdf

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A090 JP1977-837_Hitachi_Koike.pdf

A091 JP1978-1971_Toshiba_Yamada_VOD_patent.pdf

A092 JP1980-138026_NEC_Teranishi_Patent.pdf

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A093 P1976_128_bit_Comparator.pdf

A094 P1978_Pinned_Photodiode_1978_Paper_by_Hagiwara.pdf

A095 P1979_CCD79_in_Edinburgh_1979.pdf

A096 P1989_SONY_4MSRAM_1989.pdf

A097 P1996_Pinned_Photodidoe_used_in_Sony_1980_FT_CCD_Image_Sensor.pdf

A098 P2001_ESSCIRC2001.pdf

A099 P2008_ESSCIRC2008Hagiwara.pdf

A100 P2013_ISSCC2013PanelTalk.pdf

A101 P2019_3DIC2019Paper_on_3D_Pinned_Photodiode.pdf

A102 P2020_EDTM2020_PaperID_3C4_by_Hagiwara.pdf

A103 P2020_Pinned_Photodiode_Solar_Cell_1.pdf

A104 P2020_Pinned_Photodiode_Solar_Cell_2.pdf


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A105 Buried_Photodiode_is_not_always_PPD_Hagiwara_Nov_2020.pdf

A106 Difference_of_Pinned_Photodiode_and_Buiried_Photodiode.pdf

A107 E-mail_Communication_on_Sony_Loral_Patent_War_1996.pdf

A108 E-mail_communication_with_Albert_san_and_Yoshi.pdf

A109 Evidence_that_Hagiwara_is_the_inventor_of_Pinned_Photodiode_2020_10_04a.pdf

A110 Evidence_that_Hagiwara_is_the_inventor_of_Pinned_Photodiode_in_Japanese.pdf

A111 Hagiwara_invented_PPD_and_Sony_HAD_in_1975.pdf

A112 Hagiwara_invented_PPD_and_Sony_HAD_in_1975_2020_08_21.pdf

A113 Hagiwara_invented_PPD_and_Sony_HAD_in_1975_Head.pdff

A114 Image_Sensor_Story_07.pdf

A115 Image_Sensor_Story_14.pdf

A116 Origin_of_1975_Concept_of_Pinned_Photodiode.pdf

A117 The_evidence_that_Hagiwara_is_the_inventor_of_Pinned_Photodiode_2020_10_02 .pdf


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A118 Hagiwara_invented_PPD_and_Sony_HAD_in_1975.html
>
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

A119 AIPS Library
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Past Homepage Backups

A120 2021_03_01

A121 2021_01_23

A122 2020_12_22
A123 2020_12_17
A124 2020_12_15
A125 2020_12_09

A126 2020_06_27

A127 2019_09_25
A128 2019_07_12

A129 2018_11_29




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--P032--



--P033--



--P034--




--P035--


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

My Wonderful Memory Pictures

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Hagiwara had to defend his 1975 Pinned Photodiode Basic Patents
JPA 1975-127646, JPA 1975-127647 and JPA 1975-134985
from Faircild, NEC and Kodack Patent Attacks
more than 15 years from 1990 till 2015.

Sony won the Farichi/Sony Patent War in 2000.
NEC gave up patent disputes and stopped image sesnor business.
Sony and Kodak made a friendly technical cross liscence mutual agreement.


--P036--


Sony and Kodak made a friendly technical cross liscence mutual agreement

while NEC gave up patent disputes and stopped image sesnor business..



--P037--



The chairman of Sony, Mr. Ohga and other Sony Executives were very happy
about the happy result of the Patent War.


--P038--




--P039--





--P040A--




--P040B--




--P040C--



--P040D--




Hagiwara also received the Sony Central Research Center Crystal Award in 1978
for his image sensor time and space spectrum analysis.


--P041A--





--P041B--



--P041C--




--P041D--


A130 Sony_acknowledged_that_Hagiwara_invented_PPD_with_VOD_for_Electric_Shutter_Function



--P042A--





--P042B--




--P042C--





--P042D--


Prof. Yoshiaki Hagiwara at Sojo University was on TV

The AIPS Self Driving Cars are on the way in near future.




--P043--

>*********************************************************************
Hagiwara_Japanese_Patents_and_Published_Papers_PDF_Files
*********************************************************************

A131 1_Sony_vs_Loral_Patent_War_1_Reviews.pdf

A132 1_Sony_vs_Loral_Patent_War_2_Supporting_Opinions.pdf

A133 1_Sony_vs_Loral_Patent_War_3_E-mail_Communication_on_Sony_Loral_Patent_War_1996.pdf

A134 1_Sony_vs_Loral_Patent_War_4_E-mail_communication_with_Albert_san_2018_07_10.pdf

A135 1_Sony_vs_Loral_Patent_War_5_HAD_sensor_NEC_SONY_Patent_War.pdf

A136 1_Sony_vs_Loral_Patent_War_6_JP1980_138026_NEC_Buried_Photodiode_Patent.pdf

A137 1_Sony_vs_Loral_Patent_War_7_JP1978-1971_Toshiba_Yamada_VOD_patent.pdf

A138 1_Sony_vs_Loral_Patent_War_53_pages.pdf

*********************************************************************


A139 1_Sony_vs_Loral_PAtent_War_13_pages.pdf

A140 2_The_evidence_that_Hagiwara_is_the_inventor_of_Pinned_Photodiode_7_pages.pdf

A141 3_JP1975-127646_NPNP_triple_junction_Pinned_Photodiode_Patent_32_pages.pdf

A142 4_JP1975-127647_NPN_double_junction_Pinned_Photodiode_Patent_22_pages.pdf

A143 5_JP1975-134985_PNP_double_junction_Pinned_Photodiode_on_Nsub_Patent_7_pages.pdf

A144 6_JP1977-126885_Elecric_Shutter_Clocking_Scheme_by_OFD_Punch_Thru_Action_13_pages.pdf

A145 7_JP2014-135497_Digital_Transformation_Circuit_for_Image_Sensors_29_pages.pdf

A146 8_JP2020_131313_on_Doubel_Junction_Pinned_Photodiode_Solar_Cell_65_Pages.pdf

A147 9_P1978_Pinned_Photodiode_1978_Paper_by_Hagiwara_7_Pages.pdf

A148 10_P1996_Pinned_Photodidoe_used_in_Sony_1980_FT_CCD_Image_Sensor_9_Pages.pdf

A149 11_P2001_ESSCIRC2001_Micro-Electronics_for_Home_Entertainment_11_pages.pdf

A150 12_P2008_ESSCIRC_2008_SOI_Design_in_Cell_Processor_and_Beyond_7_pages.pdf

A151 13_P2013_ISSCC2013_Panel_Talk_25_pages.pdf

A152 14_P2017_CoolChips_Panel_170419_29_pages.pdf

A153 15_P2019_3DIC2019_Paper_on_3D_Pinned_Photodiode_6_pages.pdf

A154 16_P2020_EDTM2020_PaperID_3C4_by_Hagiwara_4_pages.pdf

A155 Hagiwara_Japanese_Patents_and_Published_Papers_302_pages.pdf



++++++++++++++++++++++++++++++++++++++++++++++++++++++++
The Evidence that Yoshiaki Hagiwara at Sony Invented Pinned Photodiode in 1975.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Dear Sir


Your honest, free and neutral opinion on the history of invention
and development efforts of image sensors is very important.

The truth should be revealed to all of the people in the world.
You are just one of them. But each one is very, very important.


I summarized my point of view on the history of the invention and the development efforts
of Pinned Photodiode. When I jointed SONY in 1975 after receiving PhD from Caltech, Sony
people understood the importance of the CCD complete charge transfer operation and the
excellent feature of no image lag in the CCD/MOS dynamic photo capacitors. However
Sony was suffering the yield problem due to the strong surface electric field and the
poor short wave blue light sensitivity since the CCD/MOS dynamic photo capacitors have
the metallic polysilicon electrodes which do not pass the short wave blue light. As you may
know the short wave blue light cannot penetrate more than 0.1 micro meter in depth in
the silicon crystal. The double dynamic photo transistor and the triple junction photo
thyristor were the answers which do not have the surface electric field nor the metallic
electrodes. I applied Japanese patents JP1975-127646, JP1975-127647 and JP1975-134985.
The proposed photodiodes were intended to be applied to the interline CCD image sensors
as explained in my Japanese 1975 patents . I developed the P+NP double junction type photodiode
in 1978 used it in the FT CCD image sensors and reported at SSDM1978 conference in Tokyo.
After that , SONY kept silent since it was a top secrete project in SONY. SONY took more than
8 years to develop and make the passport size portable video cameras with the P+NPN triple
junction type photodiode with the in-pixel overflow drain with the complete electrical
shutter function for action pictures. Sony was only the maker who could produce the camera.

I summarized the details in the site shown below. The problem was that I forgot completely
myself the details of my 1975 inventions since I was busy since 1980 in developing the system
LSI chip sets such as for the SONY AIBO robots and the PS2 and PS3 Play Station Game Machines.

I uploaded here the complete form of my point of view on the PPD invention and development efforts.

I wish people would kindly read this for me and let me know what they think about this.

I am not asking your opinion on the patent issues. Patent issues
were already settled and no problems. Sony is now enjoying the
image sensor business being protected by Hagiwara 1975 Pinned
Photodiode patents. KODAK , NEC and Fairchild also did apply
similar PPD patents. But they were all applied later than 1975.

I am asking your opinion on who is the inventor and who
first developed Pinned Photodiode and reported in the
international technical conference.

These facts are important for the history of image sensors and
have very important meanings as back ground information
and for educational purpose for young generations who
may have interest in image sensors and its history.

The SSDM1978 Conference held in Tokyo in 1978 is also an
international conference but with a very limited number.

The published SSDM1978 conference journal paper is not widely accessed.

But Albert Theuwissen found my SSDM1978 paper after 18 years
and quoted my original 1978 PPD work in his IEEE2006 paper.

<001>P1978_SSDM1978_Paper_quoted_in_2006_paper.jpg




Albert Theuwissen did not emphasize the complete charge transfer feature of
Pinned Photodiode since CCD has already the complete charge transfer feature.

The complete charge transfer feature was nothing new.

The importance of Pinned Photodiode were

(1) The excellent short wave blue sensitivity and

(2) the Low Surface Dark Current.

Firstly, since CCD has the metal electrode, it has a poor short wave
blue light sensitivity.

Secondly, the CCD/MOS dynamic photo capacitor has a strong surface electric field
which induces the undesired surface dark current.

However, Albert Theuwissen apparently and SONY( Hagiwara) already understood
the feature of the complete charge Transfer mode of Pinned Photodiode.


NEC IEDM1982 paper by Teranishi reported the importance of the image lag feature
of Buried Photodiode. But Buried Photodiode is not always Pinned Photodiode.

NEC IEDM1982 paper by Teranishi also reported the serious undesired image lag
feature of the NEC1982 Buried Photodiode in the IEDM1982 paper. Any photodiode
with image lag feature is not Pinned Photodiode according to the Fossum Paper.

Hence NEC IEDM1982 paper was not Pinned Photodiode by definition.

<002>NEC_IEDM1982_Paper_was_not_Pinned_Photodiode_by_definition(jpg)




Many people were misled by Fossum paper.

<003>Many_people_were_misled_by_Fossum paper(jpg)





The Difference of Pinned Photodiode and Buried Photodiode was well explained in
the article which says ,"...acknowledge Hagiwara-san's contribution.It has long
been incorrectly attributed to Teranishi and to Fossum (in CMOS image sensors)"


<004>Difference-between-Buried-Photodiode-and-Pinned-Photodiode(html)



"A pinned PD is designed to have the collection region deplete out when reset.
AS the PD depletes it becomes disconnected from the readout circuit and
if designed properly will drain all charge out of the collection region
(accomplishing complete charge transfer). An interesting side effect is
that the capacitance of the PD drops to effectively zero and therefore
the KTC noise qn=sqrt(KTC) also goes to zero. When you design the depletion
of the PD to deplete at a certain voltage you are pinning that PD to that
voltage. That is where the term comes from. I've edited this Answer to
acknowledge Hagiwara-san's contribution. It has long been incorrectly
attributed to Teranishi and to Fossum (in CMOS image sensors)"

Actually the in-pixel active sensor was first invented and reported
in 1968 by Peter Noble at Plessy in England UK before Fossum work in 1990.


These truth was not well understood widely.

Teranishi and Fossum are well received to the world for their contributions.

But they never quoted Hagiwara and Noble previous old works.

The people misunderstood that Teranishi and Fossum were
the first inventors and the first developers.

Patent issues are settled and now Sony enjoy the image
Sensor business with advantage over KODAK, NEC ,
Fairchild and other competing companies. Sony has
Hole Accumulation Diode (HAD) which is identical to
Pinned Photodiode in the world wide business with
more than 60 to 70 % share of image sensor devices.

Now the KODAK-named Pinned Photodiode reported in IEDM1984
is now considered as the invention by Teranishi at NEC in 1980,
according to the paper "A Review of the Pinned Photodiode
for CCD and CMOS Image Sensors" by E.Fossum. This Fossum
paper was attacking Hagiwara 1975 patent and SSDM1978
paper with misleading descriptions on no image lag issue.

Hagiwara 1975 patent and SSDM1978 paper did report the
complete charge transfer operation and showed the empty
potential well profile which are signs of no image lag feature.


The truth is that Hagiwara proposed 1975 the now-called
Pinned Photodiode in form of the double PNP and triple PNPN
junction dynamic photodiodes originally.


The double PNP and triple PNPN junction dynamic photodiodes
in 1975 and reported the double PNP junction dynamic
photodiode in Hagiwara SSDM1978 paper.

The patent issues were settled and no problems.
In the secret patent disputes and the public US courts ,
Fairchild, KODAK, NEC in the past attacked Sony on the
basic Pinned Photodiode patents but they were all not
successful. NEC gave up image sensor business and
Fairchild and KODAK made friendly technical agreements
with Sony now. I am not asking about the patent issue.

I need to hear your personal opinion on the historical background
of the invention and the Innovation efforts of Pinned Photodiode.

The truth should be revealed to all of the people in the world.

You are just one of them. But each one is very, very important to me.

Fossum paper claims that Hagiwara JPA1975-134984 and
Hagiwara 1978 paper did not describe the image lag feature.

I believe Fossum misunderstood my 1975 patent and 1978 paper.

Hagiwara JPA1975-134984 showed an empty potential of
the buried N storage region of the double junction PNP
dynamic photo transistor structure with the emitter and
the collector terminals both pinned, which is identical to
Pinned Photodiode. As you know the empty potential well
implies the complete charge transfer operation which results
in the excellent feature of no image lag in video camera.

Hagiwara SSDM1978 paper reported the output wave forms of
the image sensor using the double PNP junction photodiode
with the pinned P+ surface region directly connected to
the adjacent P+ channel stops, which is also identical to
the definition of Pinned Photodiode. The output wave forms
showed a very low total surface dark current of less than 3%
and the complete charge transfer efficiency of more than 99.995%
which implies the excellent feature of no image lag.

My work was cited in "A Review of the Pinned Photodiode for CCD
and CMOS Image Sensors" by E.Fossum. Actually E.Fossum was
attacking my 1975 PPD patent and SSDM1978 PPD paper.

Please kindly read carefully Fossum paper. Fossum was not telling
the truth about Hagiwara 1975-134985 patent and Hagiwara
SSDM 1978 paper. Fossum paper was misleading and had a wrong
conclusion.

I have reported the image lag feature of the complete charge
transfer operation both in my 1975 PPD patent and SSDM1978
PPD paper. Fossum did not read carefully or does not understand
the details of my 1975 PPD patent and SSDM1978 PPD paper.

The truth should be revealed to all of the people in the world.
You are just one of them. But each one is very, very important to me.

I would like to hear your personal opinion on this.


For your information, Sony wrote an article
regarding the original invention of Pinned Photodiode
in the Sony Official Homepage:

<005>https://www.sony.com/en/SonyInfo/News/notice/20200626/


And Sony explained and claimed,

"In 1975, Sony invented a CCD image sensor that adopted a back-illuminated N+NP+N junction type
and an N+NP+NP junction type Pinned Photodiode (PPD) (Japanese patent application number
1975-127646, 1975-127647 Yoshiaki Hagiwara). In the same year, inspired by such structure,
Sony invented a PNP junction type PPD with VOD (vertical overflow drain) function (Japanese
Patent No. 1215101 Yoshiaki Hagiwara). After that, Sony succeeded in making a principle prototype
of a frame transfer CCD image sensor that adopted the PNP junction type PPD technology, having a
high-impurity-concentration P+ channel stop region formed near a light receiving section by ion
implantation technology for the first time in the world, and its technical paper was presented
at the academic conference, SSDM 1978 (Y. Hagiwara, M. Abe, and C. Okada, "A 380H x 488V CCD
imager with narrow channel transfer gates", Proc. The 10th Conference on Solid State Devices,
Tokyo, (1978)). In 1980, Sony succeeded in making a camera integrated VTR which incorporated
a one-chip frame transfer CCD image sensor that adopted the PNP junction type PPD. President
Iwama in Tokyo, Chairperson Morita in New York, at the time held a press conference respectively
on the same day, which surprised the world. In 1987, Sony succeeded in developing a 8 mm video
camcorder that adopted, for the first time in the world, the interline transfer CCD image sensor,
which incorporated "PPD having a high-impurity-concentration P+ channel stop region formed near
the light receiving section by ion implantation technology" with VOD function, and became the
pioneer of the video camera market. The PPD technology that has been nurtured through such a
long history is still used in back-illuminated CMOS image sensors."


The Society of Semiconductor Industry Specialists (SSIS) of Japan
Society of Semiconductor Industry Specialists (ssis.or.jp)
also wrote an article regarding the original invention of Pinned Photodiode
on the SSIS official Homepage:

<006>https://www.shmj.or.jp/english/pdf/dis/exhibi1005E.pdf


The Society of Semiconductor Industry Specialists (SSIS) of Japan explained
and claimed in details as

"The Pinned Photodiode is a photodiode in which the entire N layer is
covered with a P layer. The part of the P layer on the light incident
surface is heavily doped P+. Kodak named this structure Pinned Photodiode
in 1984 because the P+ surface of the light incident surface was pinned
to the substrate potential.

This device has features such as high light sensitivity, wide dynamic range,
image lag free, much smaller dark current due to reduced influence of GR center
on the light receiving surface, and no white scars.

In 1975, Sony proposed using a PNP transistor as the photodetector [3].
By providing a P+ layer (emitter) for the light incident section,
the sensor electrode that covers the entire light receiving surface of
the photodiode can be eliminated to improve the light sensitivity greatly.
It was a basic proposal for a pinned photodiode with a P+ layer on the surface
of the light receiving part."

The reference [3] is my original Japanese Patent on Pinned Photodiode.
The photodiode structure was originally defined as the double PNP dynamic photo transistor
and the triple junction PNPN dynamic photo thyristor in my patent application Jp1975-134985.

[3] Y. Hagiwara, Japanese Patent JP1975-134985

<007>JP1975-134985_Patent_on_the_PNP_Double_Junction_Pinned_Photodiode_on_Nsub(pdf)


The structure was later called as Buried Photodiode by NEC in 1982, Pinned Photodiode by KODAK in 1984,
and as the Hole Accumulation Diode (HAD) by Sony in 1987.

But all of them are identical to my 1975 invention.

I believe I am the inventor of Pinned Photodiode in 1975 and developed Pinned Photodiode in 1978.

<008>P1978_SSDM1978_Paper_on_the_P+PN_Double_Junction_Pinned_Photodiode_by_Hagiwara(pdf)

And Sony built the video movie camera used Pinned Photodiode
in the one chip NTSC full size Frame Transfer CCD image sensor in 1980

The details of my works are explained in the following publications.

Would you kindly read my papers and let me know your personal opinion on
who really invented Pinned Photodiode and developed it for the first time in the world ?


<009>P2021_IJSSA2021_Paper_on_Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes(pdf)


++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Paper Accepted with a minor revision. Reviews' Comments:
++++++++++++++++++++++++++++++++++++++++++++++++++++++++

"This is a comprehensive paper, well designed, performed and written.
The logicality of this paper is quite good and the main body provides
sufficient information. The study abstract is concise and clearly presented,
and the figures in the article have well illustrated the study. Meanwhile,
the author gives a comprehensive description in conclusion.
This is a very instructive research. It is suggested that recommendations
for follow-up or future work on this topic should be made."

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
List of Related Published Papers on Pinned Photodiode
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++

<010>P1978_SSDM1978_Paper_on_the_P+PN_Double_Junction_Pinned_Photodiode_by_Hagiwara(pdf)


<011>P1979_CCD79_in_Edinburgh_Invited_Paper_by_Hagiwara.pdf


<012>P1996_IEEE_Paper_on_Pinned_Photodidoe_used_in_Sony_1980_FT_CCD_Image_Sensor.pdf


<013>P2001_ESSCIRC2001_Invited_Talk_on_Micro_Electronics_for_Home_Entertainmen_by_Hagiwara.pdf


<014>P2008_ESSCIRC2008_Invited_Talk_on_SOI_Design_in_Cell_Processo_and_Beyond_by_Hagiwara.pdf


<015>P2013_ISSCC2013_Invited_Panel_Talk_on_the_PNPN_Diode_in_Future_Linear_Motor_Cars_and_in_Modern Imager_by_Hagiwara.pdf


<016>P2017_CoolChips_Invited_Pane_Talk_on_Cool_chips_for_the_next_decade_by_Hagiwara_20l170419(pdf)


<017>P2019_3DIC2019_Paper_on_Multichip_CMOS_Image_Sensor_Structure_for_Flash_Image_Acquisition(pdf)


<018>P2020_EDTM2020_Paper_ID_3C4_on_Simulation_and_Device_Characterization_of_Pinned_Photodiode(pdf)


<019>P2021_IJSSA2021_Paper_on_Electrostatic_and_Dynamic_Analysis_of_Pinned_Photodiodes(pdf)


++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Unfortunately these Japanese Patent Applications of mine shown below were
written only in Japanese language and were never disclosed in details to
the English Speaking Community.

<020>JP1975-127646_NPNP_triple_junction_Pinned_Photodiode_Patent_32_pages.pdf


<021>JP1975-127647_NPN_double_junction_Pinned_Photodiode_Patent_22_pages.pdf


<022>JP1975-134985_PNP_double_junction_Pinned_Photodiode_on_Nsub_Patent_7_pages.pdf


<023>JP1977-126885_Elecric_Shutter_Clocking_Scheme_by_OFD_Punch_Thru_Action_13_pages.pdf



Very Sincerely

Yoshiaki Hagiwara

hagiwara-yoshiaki@aiplab.com

<024>http://www.aiplab.com


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hagiwara-yoshiaki@aiplab.com for my activity at http://www.aiplab.com/
hagiwara@ssis.or.jp for my activity at http://www.ssis.or.jp/en/index.html
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