VLSI cryogenic front-end for HPGe detectors based on a silicon-germanium technology

Abstract

We studied the feasibility of monolithic silicon-germanium front-ends for cryogenic semiconductor detectors. In this framework we designed and simulated a low-noise Charge Sensitive Preamplifier for High Purity Germanium detectors using the Austria Micro System S35 silicon-germanium technology. The preamplifier uses two silicon-germanium Hetero-junction Bipolar Transistors, a few silicon Metal-Oxide-Silicon Field-Effect Transistors, and an external silicon Junction Field-Effect Transistor. It is designed for gamma-ray spectroscopy performance at liquid-argon temperature, and exploits the full functionality at cryogenic temperatures of silicon-germanium Bipolar Transistors. Single-channel and four-channel versions are being realized.