On Analog Silicon Photomultipliers in Standard 55-nm BCD Technology for LiDAR Applications

TL;DR

This paper introduces an analog silicon photomultiplier (SiPM) fabricated in 55 nm BCD technology, demonstrating its suitability for compact, high-precision LiDAR systems with integrated timing and imaging capabilities.

Contribution

The paper presents a novel SiPM design in standard 55 nm BCD technology, integrating 16×16 SPADs with high timing resolution for LiDAR applications.

Findings

Achieved a gain of 3.4×10^5 at 5 V bias

Single-photon timing resolution of 185 ps

Depth measurement accuracy of 2 cm at 25 m

Abstract

We present an analog silicon photomultiplier (SiPM) based on a standard 55 nm Bipolar-CMOS-DMOS (BCD) technology. The SiPM is composed of 16$\times$16 single-photon avalanche diodes (SPADs) and measures 0.29$\times$0.32 mm$^2$. Each SPAD cell is passively quenched by a monolithically integrated 3.3 V thick oxide transistor. The measured gain is 3.4$\times$ 10$^5$ at 5 V excess bias voltage. The single-photon timing resolution (SPTR) is 185 ps and the multiple-photon timing resolution (MPTR) is 120 ps at 3.3 V excess bias voltage. We integrate the SiPM into a co-axial light detection and ranging (LiDAR) system with a time-correlated single-photon counting (TCSPC) module in FPGA. The depth measurement up to 25 m achieves an accuracy of 2 cm and precision of 2 mm under the room ambient light condition. With co-axial scanning, the intensity and depth images of complex scenes with resolutions of 128$\times$256 and 256$\times$512 are demonstrated. The presented SiPM enables the development of cost-effective LiDAR system-on-chip (SoC) in the advanced technology.