A high-current metal—Semiconductor rectifier

Schottky-barrier diodes have been in use for some time, but, in the main, only for small-signal applications. Now a large area (17K mils²) Schottky-barrier diode has been successfully fabricated for use as a high-current rectifier. The device has a rated Io of 50 amperes. Measured values of forward voltage drop at 50 amperes (dc) are typically less than 500 mV. The inherent speed characteristics of this majority carrier device were indicated in the measurement of rectification efficiency versus frequency. The efficiency of the device remained unchanged through 500 kHz. A brief theoretical review of metal-semiconductor junctions is presented and applied to the empirical characteristics of the rectifier. Chip geometry, fabrication techniques, and complete device characteristics are discussed. Specific device applications are covered with emphasis on performance and limitations.