Harvest Imaging Blog

Wednesday Feb. 10^th 2010 : Image Sensor session at the ISSCC2010.

The following papers were presented :

–       Y. Chae et al. (Yonsei University and Samsung Electronics) : “2.1 Mpixel with column-parallel ADC architecture”.  The speaker made an overview of the column level ADCs used in CMOS imagers : single slope architecture is too slow, the successive approximation has an area issue, and the cyclic ADC consume too much power.  Apparently there is a need for another architecture !  A 2^nd order Delta-Sigma ADC is implemented for the very first time as column-level ADC in a CMOS imager.  The circuitry per column is 4.5 um wide and 600 um long, it contains 320 transistors and consumes 55 uW/column.  A 2.1 Mpixel sensor is realized with the following characteristics : 2.25 um pixel, 2 sharing, 11000e- full well, 80 uV/e-, 0.013 % column FPN, 75 dB dynamic range, 180 mW @ 120 frames/s, 0.1 % non-linearity.  The noise is as low as 2.4 e- at maximum frame rate and 1.9 e- at 130 times ADC sampling.  The latter is an improvement of 54 % compared to the same device with a single slope ADC.  

–       Y. Lim et al. (Samsung Electronics) : “1.1 e- Noise CMOS imager with pseudo-multiple sampling”.  Very simple idea with surprising results : instead of using one high-resolution ADC, the ADC conversion is divided into several lower resolution ADCs.  The latter are realized as single slope ADCs with the possibility of multiple up- and down-ramps to create the multi lower resolution ADCs.  In this way a kind of multiple sampling is realized and consequently the noise is being reduced.  The device is realized in a 90 nm technology, 2.5 T shared pixel of 1.4 um, 110 uV/e- conversion gain, and 4100 e- full well.  Sensitivity of 3700 e-/lux.s and a dark current of 6.4 e-/s @ 55 ^oC.  At a frame rate of 6 fr/s a noise level of 1.1 e- was obtained with 12 bit ADC and 16x gain.

–       K. Yasutomi et al. (Shizuoka University) : “CMOS imager with dual global shutter pixels”.  It is known that with a 4T pixel in global shutter mode, the device suffers from noise issues : the leakage current of the floating diffusion is very high and in global shutter mode, CDS is no longer possible with a 4T pixel.  For that reason, the authors have implemented a double shutter in the pixels.  The first shutter implementation is a storage node between the pinned-photodiode and the floating diffusion.  This storage node is a kind of pinned-photodiode as well to keep the dark noise as low as possible.  Unfortunately the storage capacity is pretty small.  So these characteristics allow this first storage node to be used in the case of very small signals.  To transfer the charges from the pinned-photodiode into the storage node, the voltage in the storage node needs to be higher than in the pinned-photodiode, so the storage node has a different doping concentration.  (Interesting to realize that foundries are willing to change/add these implants even for university experiments !)  The construction of the storage node looks very similar to a virtual-phase CCD cell.  For larger signals, when the noise of the shutter node is less important, a second shutter architecture is used, being the classical one : storage on the floating diffusion.  These two storage nodes are designed fully in parallel.  Results : shutter efficiency of the first shutter is 99.7 %, of the classical one it is 99.9 %, dark current of the first shutter is 119 e-/s @ 27 ^oC and is 1221 e-/s for the second one, also at 27 ^oC.  The pixels are 7.5 um in size and have a fill-factor of 25 %.  Full well is 10000 e- and the conversion gain is 38 uV/e-.

–       C. Posch et al. (Austrian Institute of Technology) : “Address event PWM image sensor with lossless pixel-level compression”.  Every frame in a video sequence contains a lot of redundant information, and based on that knowledge the authors created a kind of device that only outputs changes in the scenery.  In this way a large amount of output data can be reduced, without any loss in information.  The pixels become quite complex : 77 T, but the data reduction factor is quite impressive : up to 400 fully lossless.  During the presentation a very nice video demonstration was shown to illustrate the working principle of the device.

Will be continued !

Albert 2010-02-11

Being the Technical Program Chair of the ISSCC2010, yesterday morning (Monday Feb. 8th 2010) I had the honor to officially open the conference.  It was the first time in my life to speak in front of an audience of 2600 attendees.  Very impressive view looking from the podium over such a crowd of people.

At the International Solid-State Circuits Conference one of the four plenary talks was delivered by Tomoyuki Suzuki of Sony (Senior VP).  He gave an amazing overview of Sony’s history in the CCD field.  We all know that Sony has a long track record in high-performance CCD imagers, but nevertheless the improvements Sony implemented in the CCD technology is quite impressive.  Just to name a few (not necessarily all are invented by Sony but all are used in their products) :

–       1987 : vertical overflow drain allowing an anti-blooming in the third dimension, without losing any fill factor in the pixel,

–       1987 : HAD sensor, being the hole-accumulation diode or the pinned photodiode, with the capability of instant charge reset,

–       1987 : on-chip colour filters,

–       1989 : high energy implanter to allow a deeper p-well for the CCD, resulting in a better smear and a higher quantum efficiency,

–       1989 : on-chip microlenses,

–       1995 : on-chip colour resist filters,

–       1995 : epitaxial wafers to reduce cross-talk and smear,

–       1997 : inner lenses being a second microlens,

–       1997 : gapless microlenses,

–       2000 : double inner lenses,

–       2000 : tungsten light shield for an improved smear engineering,

–       2004: single layer transfer electrode, to increase yield and surface flatness of the sensors, resulting in a better angular response,

–       2008 : new wiring technology for the electrodes aiming for high-speed imaging.

Looking through this list it must be possible to imagine or visualize the 3D stack of which the photodiode is part of.  Such a CCD pixel is a beautiful example of vertical integration starting deep in the silicon and extending several micrometers on top of the silicon.

Looking towards CMOS imaging, Suzuki-san named the following challenges :

– Pixel shrinkage, for which he suggested to move from aluminum interconnects to copper interconnects,  this will drastically decrease the optical stack on top of the silicon.  Although this technique is not really new, he showed beautiful SEM cross-sections of the pixel structures,

– Frame rate, for which he highlighted the column-level ADC architecture implemented by Sony and based on an up/down counter in every column, this work was awarded with the Walter Kosonocky Award in 2007,

– Sensitivity of the small pixels for which he showed results of Sony’s back-side illumination technology.  He also showed some data coming from a new 10.3 Mpixel CMOS imager with 1.65 um pixel size : sensitivity almost 10,000 e^–/lux.s, saturation : 9130 e^–, conversion gain 75 uV/e^–, 1.7 e^– rms noise in dark (gain 16x), dark current 3 e^–/s at 60 ^oC, and a dynamic range of 71 dB.  Also of this sensor a very nice SEM cross section was shown which revealed some interesting details of the technology.

The following near-term trends for CMOS imagers were reported :

–       Ultra high speed,

–       Global shutter,

–       Wide dynamic range,

–       Increasing depth of field.

At the end of the talk Suzuki-san referred to two new future imaging functions being 3D imaging and curved image sensors.  In other words, an interesting future is lying ahead of us !  

Albert 09-02-2010

It is today that the ISSCC officially starts, but yesterday the tutorials, two forums and two evening sessions were organized.  For the imaging community, the “Silicon 3D-Integration, Technology and Systems”  forum was of interest. And especially the talk by Jean-Luc Jaffard of ST Microelectronics, entitled : “Chip Scale Camera Module Using Through Silicon Via Technology”.  The agenda of his presentation looked as follows :  imager market outlines, camera module physical size contributing factors, optical technologies, through silicon via process, camera module assembly and reliability, future evolutions and conclusions.

In general this talk could be seen as a great overview of the state-of-the-art of TSV for imagers.  For the non-imaging experts in the room the talk contained a lot of new information (and basically the forum was addressing a broad spectrum of interested people, not just imaging experts).  For the imaging engineers, the most interesting part was situated in the second half of the talk.

Jean-Luc showed a nice comparison of pros and cons of an injected plastic lens, a molded glass lens and wafer level optics.  Basically wafer level optics go hand-in-hand with TSV technology.  A series of cartoons illustrated the process of the TSVs, as well as the future integration of camera modules : wafer lens, TSV sensor, image processing, memory all stacked on top of each other as a real 3D masterpiece.  Discussing about the wafer level camera roadmap, Jean Luc mentioned that today the modules already make use of wafer level optics, but that the modules are still individually assembled.  Next step will be the combination of wafer level optics and TSV sensors bonded before dicing, while in a couple of years from now  we will see wafer level optics, including auto-focus means, bonded to a TSV sensor before dicing. 

If someone thinks that the development of camera modules soon will come to an end, the answer is simply NO ! 

Albert, 08-02-2010

Wishing your a good mornig from my hotel room in San Francisco.  Basically the International Solid-State Circuit Conference is ready to start !  Over 95 % of the presenters arrived already and had yesterday, Saturday, a long rehearsing day.  Today the plenary speakers will rehearse in the big ballroom, while in parallel the educational activities will start.  On Sunday we will have 9 tutorial sessions (each 1.5 hour) running in two parallel tracks.  That allows those who are interested to attend maximum 2 or 3 tutorials.  Attending a tutorial is a very nice way of getting familiar with certain topics in new fields.  Also on Sunday the first 2 forums are organized.  A forum is a full-day event focusing on one particular topic with for instance about 7 invited top experts in their field.  In one of two today’s forums (“Silicon 3D Integration Technology and Systems” and “Reconfigurable RD and Data Converters” , Jean-Luc Jaffard of ST Microelectronics will talk about TSV for imaging modules.   I do hope that I can attend Jean-Luc’s presentation, I can not follow the complete program due to other obligations.  As there are the plenary rehearsals that I have to chair.

This evening a first evening session is organized (“Beyond CMOS – Emerging Technologies”)  in parallell to the Student Research Preview.  The latter gives MSc and PhD students the opportunity to present their work during a flash presentation and by means of a poster.

Starting from tomorrow, Monday, the paper presentations will start.  I do hope to give you a short update on a daily basis of what is/was important for the imaging community.  I hope you will like it.

Albert, 07-02-2010

At the end of the 2009 I would like to take the opportunity to wish all my readers a Merry Christmas and a Happy New Year. 

Everyone is telling that the economy is recovering, let’s hope that this will be the driver for a successful 2010.  I heard from various industrial sources that CCD fabs as well as CMOS fabs are completely filled with image sensor wafers.  Apparently the future for imaging looks bright.

Looking back to 2009, it was a difficult year for many of us in the imaging business.  If I look to my own activities, 2009 started with a drastic reduction in attendees of the ISSCC2009.  If I recall the numbers, the amount of participants was about 66 % of the previous years.  Being the vice chair of the technical program committee, I was reponsible for the evening and educational activities.  Also within the ISSCC organization “cost-cutting” became a buzz-word.    As far as my own teaching activities were concerned, in the first half of 2009 the number of in-house trainings dropped, and several public courses had to be cancelled because of lack of participants.  Despite all the negative signals, the International Image Sensor Workshop in June was a big success.  Being the general chair of the workshop, I was very much concerned about the financial consequences if we had to face a low number of papers and/or participants.  But the workshop was sold out in just a few days, Johannes Solhusvik helped me putting together a very strong technical program, and we combined the workshop with a one-day symposium on BSI which attracted a lot of attention. 

After the Summer holidays, the teaching and training activities started to recover.  New in-house courses were organized, and in the Fall of 2009 only one public course needed to be cancelled.  The drop in number of courses in the middle of the year gave me the time to work on other items, and the result of that will be a brand new course in 2010.  Although I am still working on it, the course will become available in the second half of 2010.  It will be the first course ever in digital imaging with hands-on evaluations and measurements in the class room.  New hardware is acquired (11 cameras, light boxes, power supplies, laptops, etc.) and at this moment I am preparing the exercises for the course.  The first four experiments are ready : illustrating the improvement in S/N when multiple images are averaged, measuring the fixed-pattern in dark (pixel, column and row FPN), measuring the temporal noise in dark and measuring the pixels with random-telegraph pattern (RTS pixels).  More assignments will follow.  It is a lot of work, but it is also a lot of fun to prepare the set-ups.  I am really looking forward to work with it in a class room.  So 2010 will bring its own challenges, but it so much more motivating to work on these positive challenges to expand and improve my own business.

I wish all of you the very best for 2010, and hope that we will regularly “meet” through this blog.  Thanks for visiting the website of Harvest Imaging !

Albert, 24-12-2009.

In this short blog I would like to report on (what were for me !!) the highlights of the workshop entitled : “CMOS Detectors for High Performance Applications”, organized by Alex Materne (CNES), Oliver Saint-Pe (Astrium) and Christophe Renard (Thales Alenia Space).  Unfortunately I could not attend all presentations, so there might have been more important things presented than just shown over here.  Sorry to the presenters that I missed.

–          P. Robert (ULIS) explained how to increase the dynamic range of infra-red imagers by implementing extra capacitance in the column circuitry,

–          B. Dupont (Caeleste) showed a hybrid photon counting sensor based on SPADs,

–          B. Fowler (Fairchild Imaging) had another talk about their 5.5 Mpixel low-noise sensor.  New to me was the availability of the colour version of this sensor, as well as the back-side thinned version.  The combination of colour and back-side illumination will not be offered.  In the same talk a rad-hardness of 30 Mrad was mentioned.  Seems extremely high to me, but then the discussion popped up how the rad-hardness is defined ?  No data was given about the performance of the device in global shutter mode.  We have to wait till the upcoming SPIE conference in January 2010.

–          T. Baechler (CSEM) presented their work on in-pixel amplification with p-type transistors configured as a regulated cascade in the columns.  Cleaver idea, but at this moment no measurements are available.  An interesting model was presented to show the importance of the dark current if single photon detection is needed.

–          G. Lepage (CMOSIS) talked about the TDI option in CMOS, and how his project evolved from an analogue storage towards a digital storage on-chip for the intermediate data of the TDI.

–          J. Bosiers (DALSA) showed that a front-side illuminated CMOS imager can be light sensitive till 250 nm, at least if the appropriate measures are taken in the technology,

–          J. Pratlong (E2V) presented a large pinned (?) photodiode of 24 um x 24 um with the readout circuitry nicely placed in the middle of the diode.  Unfortunately no real details of the lay-out were shown, it would be of great interest to see how  a large conversion gain (90 uV/e-) can be obtained by such a structure.  Image lag of 5 electrons are reported, this seems a very good value for such a large pixel.

–          B. Cremers (Cypress) reported about an imager with a partially pinned photodiode.  Interesting to notice is the fact that the author talked about a couple of artifacts of the devices.  This is not that often the case that companies report about issues.

–          A. Peizerat (CEA) gave an interesting overview of requirements and options for ADCs in CMOS image sensors (die-level, column-level and pixel-level).

–          I. Djite (ISAE) talked about MTF simulation and showed his simulation results together with measurements.

–          S. Demiguel (SAGEM) focused on back-side illumination of CMOS imagers for low-light level, but the major part of his presentation was on a very nice overview of low-light level imaging options (tubes, EM, intensified, back-side illumination, other materials).

–          P. Jerram (E2V) talked about 2 CMOS imagers that are back-side illuminated.  Very nice talk with a lot of information on the BSI process itself. 

–          J. Bosiers (DALSA) highlighted their large CMOS tile of 77 mm x 145 mm, 3 sides buttable and intended for X-ray applications.  During the talk, the BSI process of DALSA was described as well, based on back-side charging to passivate the back-side of the thinned sensors.

–          P. Cemeli (Soitec) explained the back-side process in the case the starting material is SOI.  Quite a bit of technology information was given and actually this talk together with the one from P. Jerram gave an excellent overview of the ins and outs of BSI on bulk silicon and on SOI.

–          B. Dryer (E2V) presented first results on radiation damage introduced in 0.18um CMOS imagers.  Nice results but more experiments will follow.

–          Round table discussion : a panel of 8 people discussed the issues of getting access to CIS foundries for small volumes and/or for process changes.  It was concluded that process changes are out of the question (except for some small changes in implantation dose) and that the scientific/space community is that much fragmented that higher volumes can never be reached.  The only option left is to search for a common ground to increase the volumes.  This can be done by putting all roadmaps of all agencies on the table and focus on a common interest for all devices.  Otherwise the situation will not change …. and in times that the fabs are filled, the situation can only get worse.

Conclusion : interesting workshop, no registration fee, small group of people (100), good atmosphere, open discussions, no proceedings.  Thanks to the organizers !

Albert, 10-12-2009.

During the last two weeks I was not able to spend enough time preparing a new technical blog about the continuing story of the PTC.  The reason is very simple : a trip to Brazil kept me busy.

I was invited by prof. Jose Gabriel Rodriguez Carneiro Gomes (Universidade Federal do Rio de Janeiro, UFRJ) and prof. Davies William de Lima Monteiro (Universidade Federal de Minas Gerais, UFMG) to give a talk in order to promote solid-state imaging technology in Brazil.  The workshops were organized in close cooperation with the local IEEE Chapter on Circuits & Systems. 

At this moment the overall semiconductor activities in Brazil are continuously growing, but there is still very limited work going on in the field of imagers.  A few start-up companies are doing quite nice work, but they do not (yet) reach the level of the companies present in North America, Europe or the Far East.  So it was a great initiative of prof. Gomes and prof. de Lima Monteiro to promote image sensors in front of an audience composed out of undergraduate students, graduate students, professors and people from industry.  If the R&D work on image sensors gets more attention, it will be easier to get funding from the government for future projects.  And this holds for academic work as well as for industrial activities.

My talk was split into two parts (each part lasted for 2 hours) :

–       “CMOS Image Sensors : Past, Present and Future”.  The content of this session was based a short historical background, a brief overview of the state-of-the-art and focused mainly on future challenges of CMOS imaging.  If pixels get smaller and/or if more pixels are put on a sensor, the overall speed of the sensor will go down (in frames/s), the dynamic range will lower, the light sensitivity will decrease, and ultimately the signal-to-noise will deteriorate.  The talk gave an overview of the few techniques that can be used to increase the speed, to create a wide dynamic range, to increase the light sensitivity (by means of back-side illumination) and to optimize the signal-to-noise ratio (by means of pixel binning),

–       “Colour Processing”.  In a talk of 2 hours it is pretty difficult to give a detailed overview of the complete signal processing present in a digital camera.  For that reason the content of the presentation was limited to the following subjects : short overview of colour imaging, auto-white balance, colour matrixing and demosaicing.

Other speakers in the workshop were Simon Schneiter (talked about 3D Imaging) and Carlos Mendoza (talked about Smart Vision Systems).  Each workshop was attended by about 100 participants.  Based on the reaction after the workshops, the talks were very well received by the audience.  Hopefully the participants were convinced that imaging in general is a great field to work in.  If so, then more students might be attracted by the subject of solid-state imaging, and it can be a great stimulation to submit more projects.  In the end more projects will be granted, and that was the original goal of the bringing all these people together.

My first visit to Brazil was possible thanks to this great initiative taken by prof. Gomes and prof. de Lima Monteiro.  Thanks to them for inviting me this opportunity to promote digital imaging and congratulation for the perfect organization of the workshops !

Albert 01-12-2009.

The bible rewritten ? Apparently the answer to this question is YES, at least, the bible for the solid-state imaging engineer got a new edition.  Recently IEEE has published the latest special issue of Transactions on Electron Devices focusing on Solid-State Image Sensors.  After similar publications in August 1985, May 1991, October 1997 and January 2003, this is already the 5^th edition of the modern bible.  And as can be noticed, every 6 years a new edition is prepared.  In the late ‘70s, IEEE also published a special issue on Charge-Transfer Devices, but this is not considered as a special issue on image sensors.  In the case the young generation is still interested in the older ED special issues, IEEE has put all Transactions on Electron Devices ever published on a single DVD. 

The latest special issue is guest edited by Eric Fossum together with several guest co-editors (Jerry Hynecek, John Tower, Nobukazu Teranishi, Junichi Nakamura, Pierre Magnan and Albert Theuwissen).  The book contains 29 full-length papers spread over 256 pages.   All papers are grouped in the following categories :

–       Visible spectrum image sensors : several techniques to improve resolution, noise, dynamic range, conversion gain and full well are described.  What a super great performing imager could be made if we could combine all these techniques in a single device … ?

–       Modeling and simulation : also in this group the noise characteristics of the imagers get quite a lot of attention.  Not surprising of course, because noise performance is an important parameter in the definition of the dynamic range of an imager, as well as in the determination of the image quality,

–       On-chip signal and image processing : interesting to read that the CMOS world is still trying to “copy” the TDI architecture introduced many years ago in CCD technology,

–       Emerging technologies and applications : the research on alternative colour imaging techniques is still hot, as well as the retinal implants,

–       X-ray and particle image sensors : the main focus is put on medical applications, in combination with radiation damage effects.

As could be expected, most of the papers deal with CMOS image sensors, but nevertheless, a few CCD papers are included in this special issue (ultra low dark current, high-speed imaging, BSI on high-resistivity).  A nice coincidence with the announcement of the Noble Prize.

Although the quality of the published papers is quite high, it is a bit disappointing to see that the big companies active in the field are not present in this special issue.  Apparently they try to hide the information from their competitors …  Of the big ones active in the consumer imaging business, only Aptina, Toshiba, ST Microelectronics and Texas Instruments are publishing a paper in the special issue on image sensors.  Unfortunately the papers from these 4 companies contain information that was already (partly) presented in other papers or at conferences.  And that is a pitty, the R&D work performed in the large companies is of great quality and quantity.  Hopefully the trend of keeping all that information for themselves will not continue … 

Albert 2009-11-17

October 6^th, 2009 !  What a great day for the solid-state imaging community !  The Nobel Prize Physics goes to Willard Boyle and George Smith, two Bell Labs co-workers who invented the Charge-Coupled Device (CCD) !  In one of my first blogs I addressed the year 1969 when so many great things happened.  Although W. Boyle and G. Smith published their first CCD paper in 1970, probably they did most of the invention work in 1969.  With the announcement of the Nobel Prize Winners, it makes 1969 even greater than it ever was.

Let me first congratulate W. Boyle and G. Smith for receiving the greatest award one can get for his/her work : the Nobel Prize. 

I am wondering whether they ever realized that their invention would have such a great impact :

–       on the society : these days everyone has a digital still camera, many have a camcorder all provided with a CCD, some even with three CCDs.  All TV images we see today are being captured by means of CCD cameras, many medical diagnoses are relying on CCD images as well.  Other application fields are security, astronomy and scientific cameras.  In many applications these days CCDs are being challenged by CMOS image sensors, but it can easily be understood and I think that everyone agrees that CCDs paved the way in solid-state imaging, for CMOS as well,

–       on the semiconductor business : several companies (mainly based in Japan) made quite a profitable consumer business out of CCDs : examples were/are Sony, Panasonic, Sharp, Toshiba, NEC, FujiFilm.  Non-Japanese companies working in the CCD field were/are Kodak, Philips, E2V, Fairchild, DALSA, LG, Thomson, Sarnoff, SITe, Ford Aerospace, … (sorry if I forget some),

–       on the imaging technology : after the introduction of the CCDs, the classical imaging tube quickly disappeared from the scene.  CCDs were more compact, lighter in weight, less power hungry, lower supply voltage, no burn-in effects, no image lag, no maintenance and immune to electro-magnetic fields.  CCDs only had advantages over the imaging tubes, even their price was lower.  The CCDs opened a great new field of imaging applications that were never possible without solid-state image sensors,

–       on scientific and technical community : the basic CCD invention of Boyle and Smith was a great inspiration for many other great engineers : Walden invented the buried channel CCD, Esser invented the peristaltic CCD, Kosonocky was the one who invented the floating diffusion and White added the correlated-double sampling.  But I think that the CCD performance improved quite a lot after the introduction of the pinned-photodiode by Teranishi.  From that moment, the CCD business really started to boom.  I do realize that I forget many important other inventions, but they were all inspired by the one of W. Boyle and G. Smith.

Although I never met Willard Boyle and/or George Smith, personally I have to thank them as well.  Purely by coincidence I came into contact with CCDs in 1976 when I was looking after a subject for my Master thesis.  A young Ph.D. student at the University explained to me the basic working principle of the CCDs.  I was immediately attracted by the mix of digital pulses and analog CCD signals and especially by the possible applications foreseen for the CCDs (the early applications were mainly based on the analog memory capabilities of a CCD).  Later I realized that CCDs are very complex devices and do need a lot of basic semiconductor device physics to understand all aspects of their working concept.  After I obtained my Master degree I continued to work on CCDs for my Ph.D. project.  At that time I tried to replace the light-absorbing poly-silicon gates by means of transparent conductive indium-tin-oxide.  When I finished my Ph.D. studies, I joined Philips and during the recruitment interview, one of the interviewers told me it would be better for my career to switch to another topic than CCD imaging.  Strange but true, the same person hired me to work on … (as you can guess) CCDs and even today after so many years, I am still involved in the same topic, being solid-state imaging.

Thank you very much Willard and George for the great invention you did, it completely changed my personal life as well as the one of many others.  Solid-state imaging is a great field to work in, and it is a great, rewarding feeling that the Nobel Prize Physics goes to the two people who created the fundaments of it ! 

Thanks Willard, Thanks George and Many Congratulations !

Albert.

October 6^th, 2009.

As most of you probably know, I have the honor of being the Chair of the International Technical Program Committee (ITPC) of the upcoming International Solid-State Circuits Conference (ISSCC). This will take place next February in San Francisco.  Every year, this conference attracts several thousand attendees and the conference can be seen as “The Olympics” of the integrated circuit community.  Being the ITPC chair I had the luxury of choosing the conference theme, and I chose “Sensing the Future”.  Closer to my heart would have been “Imaging the Future”, but of course, ISSCC is about (much) more than image sensors.  Nevertheless, “Sensing the Future” highlights the fact that sensors have become a very important part of the integrated circuit business and will play an increasing role in future electronic applications.

The major part of the conference will be the presentation of 200+ technical papers.  The final paper selection will be done in a few weeks from now, but all the other technical and scientific activities taking place at the ISSCC2010 are already planned. 

It is then interesting to see how, where and when image sensors have found their place in these activities :

–       The conference itself will start on Monday morning with a plenary session.  One of the four plenary speaker will be Tomoyuki Suzuki, vice-president of Sony Corp.  The title of his talk will be: “Challenges of Image Sensor Development”.  I think it has been 10 years since ISSCC had a plenary talk on imagers.  If I remember well, the last one was Bryan Ackland of Bell Labs talking about CMOS imagers.  Suzuki’s abstract indicates that he will give a historical overview of milestones in the development of image sensors reached by his company.  Keep in mind that Sony was the largest image sensor supplier in the CCD era.  But he will also address the new challenges ahead of us, such as back-side illumination, 3D imaging (depth sensing), as well as 3D integration for image sensors. 

–       In total, 6 forums are planned during ISSCC2010.  Over the last 5 years, a forum on image sensors has been organized every year.  Topics like image sensor evaluation, color imaging, noise in image sensors, wide-dynamic range and medical imaging have been covered in the past. 

The day after the technical paper presentations, there will again be a one-day forum on High-Speed Image Sensor Technologies.  The organization of this forum is in the hands of Johannes Solhusvik who was also the technical program chair of the 2009 International Image Sensor Workshop. 

The exact agenda of the forum is not yet fixed, so it is too early to announce the various speakers and their subjects, but I can tell you that 8 or 9 world-experts have been invited to give presentations about the state-of-the-art and recent developments in the field of high-speed image capturing.  Topics dealing with sensor architectures, low noise options, 3D imaging, robotics and high-speed interfacing will also be addressed.  The technical content of a forum is the highest educational level one can attend at ISSCC, so the image sensor forum is absolutely something to look forward to!

Besides the forum on image sensors, an interesting talk (from ST Microelectronics) about TSV technology for camera modules will be part of the forum on 3D integration. 

–       Evening sessions : there will be no specific session devoted to image sensors, but sensors in general can be found in several evening sessions,

–       Short course on CMOS PLL.  Not specifically image sensor related, but PLLs are very important building blocks for all kind of systems-on-chip, so for imaging systems as well.

–       Tutorials : at ISSCC 9 tutorials will be presented and they cover various topics all related to integrated circuits.  One of the tutorials will be given by Kofi Makinwa and he will talk about the “Design of Smart Sensors”.  This is already the third tutorial delivered by Kofi, and as far as I recall this has never happened before at ISSCC.  Kofi is a great speaker and teacher, and that is of course the reason why he has again been invited to talk about sensors in general.

The organizational structure of the educational events of this year’s ISSCC has changed.  We have tried to incorporate more cross-functional topics in the program compared to previous conferences, and this is clearly reflected  in the various activities planned for Sunday, Thursday and the evenings.  In relation to the conference theme “Sensing the Future”, you can be sure that sensors will feature in all these activities, as will image sensors.  I am absolutely looking forward to it all, and I really must congratulate my colleagues for putting together all these great educational events.  The next step will be the compilation of an appealing program for the regular conference as well, and that will be done in a few weeks from now.

Albert 2009-09-13