PIXEL FRONTEND ELECTRONICS IN A RADIATION-HARD TECHNOLOGY FOR HYBRID AND MONOLITHIC APPLICATIONS

Pixel detector readout cells have been designed in the radiation hard DMILL technology and their characteristics evaluated before and after irradiation to 14Mrad. The test chip consists of two blocks of six rea dout cells each. Two different charge amplifiers are implemented, one of them using a capacitive feedback loop, the other the fast signal ch arge transfer to a high impedance integrating node. The measured equiv alent noise charge is 110e(-) r.m.s, before and 150e(-) r.m.s. after i rradiation. With a discriminator threshold set to 5000e(-), which redu ces for the same bias setting to 3000e(-) after irradiation, the thres hold variation is 300e(-) r.m.s. and 250e(-)r.m.s. respectively. The t ime walk is 40ns before and after irradiation. The use of this SOI tec hnology for monolithic integration of electronics and detector in one substrate is under investigation.