On-Chip RF Pulse Power Detector Using FIB as a Post-CMOS Fabrication Process

RF pulse power detectors on a CMOS chip may be useful in studying and mitigating the effects of unwanted RF radiation on chip performance. Focused ion beam (FIB) milling and ion-induced deposition were used as post-fabrication steps to build Schottky diodes on the CMOS chips fabricated using MOSIS. The standard CMOS layout of chips had Schottky diodes and was fabricated in the AMIS 0.5μ process. The directly fabricated diodes were in fact mostly ohmic and needed to be cut to fabricate FIB diodes, which showed normal diode characteristics. The FIB Schottky diodes detected pulses (i.e., bursts of 10 msec length) up to 15 GHz in the direct injection experiments, and the pulse response time was 192 ns.