GEISHA Semiconductor Reliability Studies. A Portion of CHAIR-GEISHA.
Abstract
High dose rate electron radiation studies were performed on GEISHA target diodes to total accumulated dose levels of 1.2 coulomb/sq.cm. Comparative studies were made on target diodes passivated with (1) thermal oxide (as control), (2) phosphorus glass over thermal oxide, and (3) silicon nitride over phosphorus glass/thermal oxide. All three types of diodes show initial blocking voltage (BV) degradation, followed by various degrees of BV recovery for continued radiation of all but the control diodes. The silicon nitride passivated diodes show better radiation resistance than the other two systems in that the recovery was faster and that the value of BV after the 1.2 coul/sq.cm dose level was equal to or better than the pre-radiation value. New GEISHA diodes were fabricated with a diffused guard junction around the main junction. The BV values of such structures were about 50 volts higher than the ones without the guard junction. For better radiation resistance, experiments were conducted to fabricate a metallic shield over the diode contact periphery. Development of technology for the fabrication of string diode targets was initiated using a metal 'handle' approach. Mo-Au, Ti-Au, and Ni-Au metallization systems were examined with Mo-Au giving the best results. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 08, 1971
- Accession Number
- AD0732460
Entities
People
- John R. Szedon
- Karl K. Yu