Optical Design and Characterization of CMOS Image Sensor

Speaker: Yoo Seung Lee
Affiliation: Samsung Electronics

Abstract:

CMOS image sensor market is rapidly growing since it can be used in various devices, such as camera phones, digital still and video camera, PC and tablet camera, Security camera, automotive imaging, medical imaging, etc. As stated by the trend towards high-resolution CMOS image sensors, pixel sizes are continuously shrinking, towards and below 1.0μm. Sub-micron pixel sensors are now reaching a technological limit to meet required Signal-to-Noise Ratio (SNR) performance. Thus, in order to meet these needs, it is important to develop novel structures and to optimize the structures.

This talk explains CMOS Image Sensor optical structures, design parameters and considerations to improve the performance. In particular, SNR at low-light conditions is a key performance metric. It is determined by the sensitivity and crosstalk in pixels. In order to improve sensitivity, pixel technology has migrated from frontside illumination (FSI) to backside illumination (BSI) as pixel size shrinks down. In BSI technology, it is very difficult to further increase the sensitivity in around 1.0μm pixels. However, low-light SNR can be improved by crosstalk reduction, which makes the non-diagonal elements of the color-correction matrix (CCM) close to zero and thus reduces color noise. The best way to reduce crosstalk is to introduce a complete physical isolation between neighboring pixels. ISOCELL Technology uses deep-trench isolation (DTI) which prevents optical and electrical crosstalk in active silicon region.

Biography:

Yoo Seung Lee received his B.S. and M.S. degree in physics from Sogang University, Seoul, South Korea, in 1999 and 2001, respectively, and the M.S. degree in Electrical Engineering from Columbia University, New York, NY, in 2007. He received Ph.D. in Electrical Engineering from University of Southern California, Los Angeles, CA, in 2011. He is a senior engineer in Samsung Electronics. His research interests lie in CMOS image sensor pixel design and its characterization.

For more information, contact Prof. Aydogan Ozcan ()

Date/Time:
Date(s) - May 16, 2016
1:00 pm - 2:00 pm

Location:
E-IV Elliott Room #53-135
420 Westwood Plaza - 5th Flr., Los Angeles CA 90095