DEVELOPMENT OF MICROSTRIP GAS CHAMBERS WITH MULTICHIP TECHNOLOGY

We have developed the microstrip gas chamber (MSGC) by using multi-chip technology which supports high-density assembly of bare LSI chips on a silicon wafer. Our MSGC was operated steadily with approximately 10(3) gain more than one week. An energy resolution of 15% for 5.9 keV X-ray of a Fe-55 source was obtained. With a very thin polyimide substrate of 16 mum thickness, two interesting phenomena were observed; one was a strong dependence of gains on backplane potential, and the other was little time variation of gains. We also found that a guard mask of a thin polyimide layer on the cathode edge reduced incidental electrical discharges between anode and cathode strips.