HEMT input charge preamplifier for nanoseconds signal processing time

The capabilities of the high electron mobility transistor (HEMT) as front end device in charge preamplifiers for radiation detectors have been experimentally tested. We present the design and performance of a fast low-noise charge preamplifier having an HEMT as input transistor. An equivalent noise charge of 139 rms electrons, i.e., 1.13 keV FWHM in silicon detectors, has been measured at room temperature with 10 ns RC-CR shaping and 1 pF input capacitance