Image Sensors at ISSCC 2021: Samsung 0.64um Pixel, Sony SPAD LiDAR, Sony Delta-Sigma ADC, Sony Stacked AI Processor

ISSCC has announced its 2021 Advance Program with a lot of image sensor content. It starts from a Plenary Session:

There’s More to the Picture Than Meets the Eye (and in the future it will become only much more)
Albert J. P. Theuwissen, Delft University of Technology & Harvest Imaging

Over the last five decades, solid-state imaging has gone through a difficult “childhood”, changing technology during its “adolescence”, and finally growing up to become a mature, “adult” that can compete with the human visual system when it comes to image quality. State-ofthe-art mobile devices enjoyed by consumers, rely on a multi-disciplinary mixture of analog electronics, digital circuits, mixed-signal design, optical know-how, device physics, semiconductor technology, and algorithm development. As a result, CMOS image sensors utilized in today’s mobile phones come close to perfection as far as imaging characteristics are concerned. However, this does not mean that further developments in the field are no longer necessary. On the contrary, new technologies and new materials are opening up new dimensions and new applications which complement the classical imaging functionality of sensors. This trend will ultimately convert the image sensor landscape from image capturing to smart vision. Consequently, the future of solid-state imaging will not only revolve around the shooting of beautiful images, as the market driver will no longer be limited only to mobile phones.

Session Imagers and Range Sensors has 9 papers, 4 of them are about LiDARs and ToF:

1. A 4-tap 3.5μm 1.2Mpixel Indirect Time-of-Flight CMOS Image Sensor with Peak Current Mitigation and Multi-User Interference Cancellation
   M-S. Keel, D. Kim, Y. Kim, M. Bae, M. Ki, B. Chung, S. Son, H. Lee, H. Jo, S-C. Shin, S. Hong, J. An, Y. Kwon, S. Seo, S. Cho, Y. Kim, Y-G. Jin, Y. Oh, Y. Kim, J. Ahn, K. Koh, Y. Park,
   Samsung Electronics, Hwaseong, Korea
2. A 48×40 13.5mm Depth Resolution Flash LiDAR Sensor with In-Pixel Zoom Histogramming Time-to-Digital Converter
   B. Kim, S. Park, J-H. Chun, J. Choi, S-J. Kim
   Ulsan National Institute of Science and Technology, Ulsan, Korea;
   Sungkyunkwan University, Suwon, Korea;
   SolidVue, Suwon, Korea
3. A 189×600 Back-Illuminated Stacked SPAD Direct Time-of-Flight Depth Sensor for Automotive LiDAR Systems
   O. Kumagai, J. Ohmachi, M. Matsumura, S. Yagi, K. Tayu, K. Amagawa, T. Matsukawa, O. Ozawa, D. Hirono, Y. Shinozuka, R. Homma, K. Mahara, T. Ohyama, Y. Morita, S. Shimada, T. Ueno, A. Matsumoto, Y. Otake, T. Wakano, T. Izawa
   Sony Semiconductor Solutions, Atsugi, Japan;
   Sony LSI Design, Atsugi, Japan;
   Sony Depthsensing Solutions, Brussels, Belgium
4. A 256×128 3D-Stacked (45nm) SPAD FLASH LiDAR with 7-Level Coincidence Detection and Progressive Gating for 100m Range and 10klux Background Light
   P. Padmanabhan, C. Zhang, M. Cazzaniga, B. Efe, A. R. Ximenes, M-J. Lee, E. Charbon
   EPFL, Neuchâtel, Switzerland;
   ADAPS Photonics, Shenzhen, China;
   Intuitive Surgical, Aubonne, Switzerland
   Facebook, Redmond, WA;
   Korea Institute of Science and Technology, Seoul, Korea
5. A 250fps 124dB Dynamic-Range SPAD Image Sensor Stacked with Pixel-Parallel Photon Counter Employing Sub-Frame Extrapolating Architecture for Motion Artifact Suppression
   J. Ogi, T. Takatsuka, K. Hizu, Y. Inaoka, H. Zhu, Y. Tochigi, Y. Tashiro, F. Sano, Y. Murakawa, M. Nakamura, Y. Oike
   Sony Semiconductor Solutions, Kanagawa, Japan;
   Sony Semiconductor Manufacturing, Nagasaki, Japan
6. High-Speed Back-Illuminated Stacked CMOS Image Sensor with Column-Parallel kT/C-Cancelling S&H and Delta-Sigma ADC
   C. Okada, K. Uemura, L. Hung, K. Matsuura, T. Moue, D. Yamazaki, K. Kodama, M. Okano, T. Morikawa, K. Yamashita, O. Oka, I. Shvartz, G. Zeituni, A. Benshem, N. Eshel, Y. Inada
   Sony Semiconductor Solutions, Kanagawa, Japan
   Sony Semiconductor Manufacturing, Kumamoto, Japan
   Sony Electronics, Ra’anana, Israel
7. A 0.2-to-3.6TOPS/W Programmable Convolutional Imager SoC with In-Sensor Current-Domain Ternary-Weighted MAC Operations for Feature Extraction and Region-of-Interest Detection
   M. Lefebvre, L. Moreau, R. Dekimpe, D. Bol
   Université catholique de Louvain, Louvain-la-Neuve, Belgium
8. A 1-inch 17Mpixel 1000fps Block-Controlled Coded-Exposure Back-Illuminated Stacked CMOS Image Sensor for Computational Imaging and Adaptive Dynamic Range Control
    T. Hirata, H. Murata, H. Matsuda, Y. Tezuka, S. Tsunai
    Nikon, Tokyo, Japan
9. 1/2.74-inch 32Mpixel-Prototype CMOS Image Sensor with 0.64μm Unit Pixels Separated by Full-Depth Deep-Trench Isolation
   J. Park, S. Park, K. Cho, T. Lee, C. Lee, D. Kim, B. Lee, S. Kim, H-C. Ji, D. Im, H. Park, J. Kim, J. Cha, T. Kim, I-S. Joe, S. Hong, C. Chang, J. Kim, W. Shim, T. Kim, J. Lee, D. Park, E. Kim, H. Park, J. Lee, Y. Kim, J. Ahn, Y. Hong, C. Jun, H. Kim, C-R. Moon, H-K. Kang
   Samsung Electronics, Hwaseong, Korea

In other sessions, Sony presents its AI processor stacked under CMOS sensor:

A 1/2.3inch 12.3Mpixel with On-Chip 4.97TOPS/W CNN Processor Back-Illuminated Stacked CMOS Image Sensor

R. Eki, S. Yamada, H. Ozawa, H. Kai, K. Okuike, H. Gowtham, H. Nakanishi, E. Almog, Y. Livne, G. Yuval, E. Zyss, T. Izawa

Sony Semiconductor Solutions, Tokyo, Japan;

Sony Semiconductor Solutions, Atsugi, Japan

Sony Semiconductor Israel, Hod-Hasharon, Israel

A 21pJ/frame/pixel Imager and 34pJ/frame/pixel Image Processor for a Low-Vision Augmented- Reality Smart Contact Lens

R. Singh, S. Bailey, P. Chang, A. Olyaei, M. Hekmat, R. Winoto

Mojo Vision, Saratoga, CA 

THz imaging is represented by two papers:

A 32×32 Pixel 0.46-to-0.75THz Light-Field Camera SoC in 0.13μm CMOS
R. Jain, P. Hillger, J. Grzyb, E. Ashna, V. Jagtap, R. Zatta, U. R. Pfeiffer
University of Wuppertal, Wuppertal, Germany

A 0.42THz Coherent TX-RX System Achieving 10dBm EIRP and 27dB NF in 40nm CMOS for Phase-Contrast Imaging

D. Simic, K. Guo, P. Reynaert

KU Leuven - MICAS, Leuven, Belgium

F5 forum features Sony stacked sensor presentation:

Evolving Image Sensor Architecture through Stacking Devices

Yusuke Oike, Sony, Kanagawa, Japan