Simulating enhanced photo carrier collection in the multifinger photogate active pixel sensors

Phanindra Kalyanam; Glenn H. Chapman; Ash M. Parameswaran

doi:10.1117/12.876767

16 February 2011 Simulating enhanced photo carrier collection in the multifinger photogate active pixel sensors

Phanindra Kalyanam, Glenn H. Chapman, Ash M. Parameswaran

Proceedings Volume 7875, Sensors, Cameras, and Systems for Industrial, Scientific, and Consumer Applications XII; 787508 (2011) https://doi.org/10.1117/12.876767
Event: IS&T/SPIE Electronic Imaging, 2011, San Francisco Airport, California, United States

Abstract

Classic photo gate APS uses a MOS capacitor that can capture incident illumination with a potential well created under the photogate. The major drawback of such a technology is the absorption of shorter wavelength by the polysilicon gate resulting in a higher sensitivity in the red visible spectrum than in the blue range. To reduce this we previously had experimentally shown that a multifinger photo gate APS designs with 0.72Νm fingers implemented in the 0.18 μm CMOS technology have a significant increase in sensitivity of 1.7 times the standard photo gate APS. Using advanced 2-dimensional device simulations had shown that the fringing fields form the these fingers would create a potential well shape that approached that of the standard fully covered photo gate, but with large open areas which would have less optical absorption. Reducing the gate widths resulted in higher efficiency of photo carriers generated in the larger open areas while keeping the potential well shape desired. In this work, we use optical simulation package on the 2D device simulation tools to simulate the multi finger photo gate designs with white light illumination. Sensitivity of the pixel is calculated as the count of total number of photocarriers that are collected by the potential well for a given exposure cycle. All the multifinger designs achieved a significant increase in efficiency with respect to the standard photogate APS design, with the peak sensitivity of 550% by the 7finger design with a gate width of 0.25μm.

Citation Download Citation

Phanindra Kalyanam, Glenn H. Chapman, and Ash M. Parameswaran "Simulating enhanced photo carrier collection in the multifinger photogate active pixel sensors", Proc. SPIE 7875, Sensors, Cameras, and Systems for Industrial, Scientific, and Consumer Applications XII, 787508 (16 February 2011); https://doi.org/10.1117/12.876767

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

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
12 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Device simulation

Absorption

Standards development

Sensors

Active sensors

Computer simulations

CMOS sensors

Show All Keywords

Keywords/Phrases

Search In:

Publication Years