A bulk-JFET and CMOS/SIMOX technology for low noise, high speed charge-sensitive amplifier

A monolithic integrated charge-sensitive preamplifier for high energy physics collider experiments is presented which uses n-channel JFET and p-channel MOS devices. This circuit provide an example for the gain in process flexibility if the SIMOX implantation can be patterned. The comparison of the bulk version (JFET and PMOS build in bulk silicon) and the SIMOX version (JFET in bulk silicon and PMOS on SIMOX) demonstrates that a gain of nearly a factor of 2 in circuit speed is achieved because of the reduced parasitic capacitances on SIMOX. The excellent noise behaviour and the high radiation hardness of the SIMOX version is shown.