Tap mismatch mitigation of 3µm 2tap pixels of indirect Time-of-Flight image sensor for high-speed depth mapping

Abstract

This paper presents the development of a VGA-resolution stacked back-illuminated (BI) indirect time-of-flight (iToF) image sensor with 3.0 μm 2-tap pixels. Key features of the iToF image sensor include a quantum efficiency (QE) of 38% at 940 nm, a full well capacity (FWC) of 37 ke-, demodulation contrast (Cmod) of 88% at 200 MHz, and parasitic light sensitivity (PLS) mismatch of less than -50 dB across the entire image area. Additionally, a novel 2-frame sequence without anti-frames was found to maintain comparable depth noise performance with the 4-frame sequence in both indoor and outdoor conditions. These characteristics make the sensor suitable for low-power, high depth frame rate 3D imaging in a variety of applications.

View Publication