Pixel Development for Novel CMOS Image Sensors

Abstract

Modern trends in camera module designs for both mobile and DSC applications are driving ever smaller pixels. At the same time, higher demands on the quality of the output image (DSC-like quality for mobile applications) requires maintaining pixel capacity, quantum efficiency (QE), and sensitivity, which becomes extremely difficult as the pixel size shrinks. This paper discusses pixel designs and process enhancements that enable a new generation of Image sensors with 1.75um, 1.4um, and smaller pixels with superior performance. The paper presents simulation data and experimental optical-electrical characteristics of our latest generation of 1.4um and 1.75um pixels, as well as improvements in pixel performance made through new pixel architectures and process enhancements. The paper presents performance comparisons of image sensors with different pixel sizes and array formats for the popular mobile ¼ inch optical format including Aptina’s newest 5Mpix sensor with 1.4um pixel size.