Back-side-illuminated 1.4um pixel with a vertically pinned photodiode based on hole collection, PMOS readout chain and active side-wall passivation

Bastien Mamdy; François Roy; Nayera Ahmed; Guo-Neng Lu

doi:10.1117/12.2202746

15 October 2015 Back-side-illuminated 1.4μm pixel with a vertically pinned photodiode based on hole collection, PMOS readout chain and active side-wall passivation

Bastien Mamdy, François Roy, Nayera Ahmed, Guo-Neng Lu

Author Affiliations +

Proceedings Volume 9674, AOPC 2015: Optical and Optoelectronic Sensing and Imaging Technology; 96742S (2015) https://doi.org/10.1117/12.2202746
Event: Applied Optics and Photonics China (AOPC2015), 2015, Beijing, China

Abstract

To further improve the characteristics of CMOS image sensors (CIS), we propose a back-side illuminated pixel integrating a vertically pinned and P-type photodiode (which collects holes) and PMOS readout circuitry. It has been designed in a 1.4μm-pitch, a two-transistor (2T) shared readout architecture and fabricated in a combined 65nm and 90nm technology. The vertically pinned photodiode takes up almost the entire volume of the pixel, allowing a full well capacity (FWC) exceeding 7000h⁺. With a conversion factor around 120μV/h⁺, the output swing approaching 1V is achieved on the column voltage. The pixel also integrates capacitive deep trench isolation (CDTI) to tackle electrical and optical crosstalk issues. The effective passivation of trench interface by CDTI bias control is demonstrated for a hole-based pixel. As expected, PMOS transistors have much lower trapping noise compared to NMOS counterparts. The PMOS source follower has an average temporal noise of 195μV, mainly dominated by thermal noise contribution.

Citation Download Citation

Bastien Mamdy, François Roy, Nayera Ahmed, and Guo-Neng Lu "Back-side-illuminated 1.4μm pixel with a vertically pinned photodiode based on hole collection, PMOS readout chain and active side-wall passivation", Proc. SPIE 9674, AOPC 2015: Optical and Optoelectronic Sensing and Imaging Technology, 96742S (15 October 2015); https://doi.org/10.1117/12.2202746

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available