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

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.