RADIATION EFFECTS AT CRYOGENIC TEMPERATURES IN SI-JFET, GAAS-MESFET, AND MOSFET DEVICES

Front-end electronics for liquid ionization chamber calorimetry at had ron collider experiments may be exposed to substantial levels of ioniz ing radiation and neutron fluences in a cryogenic environment. Measure ments of devices built with rad-hard technologies have shown that devi ces able to operate in these conditions exist. Several families of dev ices (Si-JFET's, rad-hard MOSFET's, and GaAs MESFET's) have been irrad iated and tested at a stable cryogenic temperature up to doses of 55 M rad of ionizing radiation and up to neutron fluences of 4 x 10(14) n/c m(2), Radiation effects on de characteristics and on noise will be pre sented.