A silicon vector light sensor for proximity sensing applications

In this paper, we introduce the 3D design of a vector light sensor for angular proximity detection applications. The sensor structure is based on creating photo sensors on side walls of micro-sized (micron scale) mesa pyramids etched in silicon. On each facet of the mesa pyramid, p-n junctions are formed and used as photodiodes. Unlike planar pixels, this 3D pixel design allows for estimation of the direction of the light incident on the sensor. We present the operating principle, fabrication details and the experimental verification of the device's performance. The sensor's unique design, simple fabrication process, and readout integrated circuit's compatibility adds merits to the current planar designs and could be utilized in angular proximity applications such as multi-focus level imaging or environment mapping for real-time dynamic virtual and augmented visualizations.