Study of a BIST Technique for CMOS Active Pixel Sensors

The production test of CMOS image sensors is complicated and expensive as an electrical and an optical test must be executed for the pixel matrix. In this paper we study a built-in-self-test (BIST) technique for the pixels. The technique is based on applying a voltage stimulus at the photosensitive element of the image sensor. The aim of this work is to avoid light stimuli to realise an only electrical test to determine if a pixel is functional or not. This will then reduce test time and test cost. To quantify the quality of this test approach, test metrics such as fault rejection and fault acceptance are estimated. Catastrophic and parametric faults are taken into consideration for the estimation of the test quality