A low noise FET with integrated charge restoration for radiation detectors

A novel pulsed, nonoptical, reset technique for use in charge-sensitive amplifiers and radiation detectors is described. The first-stage FET and charge restoration are integrated into one five-terminal device called the Pentafet. A pulse of minority carriers is injected directly into the channel of the FET. The technique is fast, and there are no aftereffects on the operation of the FET. Very low noise performance is achieved, even at high count rates. The high energy rate product capability of the device is demonstrated by analyzing Mn X-rays in the presence of high-energy electrons from an Sr-90 beta source and in a transmission electron microscope