WORKSHOP PAPER
A RGBZ 1.4 µm Image Sensor for Color and Near-Infrared Indirect Time-Of-Flight Depth Sensing on Monolithic Silicon
Abstract
A 1.2 Mpix RGB+Z image sensor with 1.4 µm pixels has been designed to simultaneously capture RGB color images with accurate color reproduction and parallax-free depth maps on a single chip. This paper presents the design and structure of this monolithic silicon-based co-integration of 1.4 µm RGB pixels with 2-tap iToF pixel (2x2 binning), fully isolated by deep trench isolation, and an on-chip optical filtering. The Quantum Efficiency (QE) of RGB pixel is close to the state-of-the-art and with a high rejection at 940 nm. The Z-pixels, taking advantage of a 5.8 µm gradually doped epitaxial layer, achieve state-of-the-art QE at 940 nm (when compared to other RGBZ systems) and a 78 % demodulation contrast at 200 MHz.Keywords
RGBZ, Time-Of-Flight, Demodulation Contrast, color reproduction, monolithic sensor, parallax-free, BSI,References
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