Detector embedded device for continuous reset of charge amplifiers: choice between bipolar and MOS transistor

This work discusses the criteria for the choice of the reset device in a charge amplifier whose front-end is integrated on high-resolution semiconductor detectors. The performances achievable using a bipolar or a MOS transistor as reset device are compared in terms of the linearity of the response and of the added noise as a function of the detector leakage current. The additional constraints in term of available technology and layout compatibility show the advantages of MOS transistors operated in sub-threshold mode.