A 50 ps resolution monolithic active pixel sensor without internal gain in SiGe BiCMOS technology

TL;DR

This paper presents a monolithic SiGe BiCMOS pixel sensor achieving 50 ps time resolution without internal gain, suitable for high-precision timing applications.

Contribution

It demonstrates a novel monolithic pixel sensor in SiGe BiCMOS technology with sub-100 ps time resolution and no internal gain, advancing high-speed detector design.

Findings

Achieved 50 ps time resolution in lab tests.

Demonstrated low noise performance with 90-160 electrons ENC.

Produced functional hexagonal pixels of 65 and 130 μm sides.

Abstract

A monolithic pixelated silicon detector designed for high time resolution has been produced in the SG13G2 130 nm SiGe BiCMOS technology of IHP Mikroelektronik. This proof-of-concept chip contains hexagonal pixels of 65 {\mu}m and 130 {\mu}m side. The SiGe front-end electronics implemented provides an equivalent noise charge of 90 and 160 electrons for a pixel capacitance of 70 and 220 fF, respectively, and a total time walk of less than 1 ns. Lab measurements with a 90Sr source show a time resolution of the order of 50 ps. This result is competitive with silicon technologies that integrate an avalanche gain mechanism.