Characteristics of high-power and high-breakdown-voltage static induction transistor with the high maximum frequency of oscillation

The design and fabrication of high-power and high-breakdown-voltage static induction transistor (SIT) with a high maximum frequency of oscillation are described and then the experimental characteristics are presented. A field plate is used to make the breakdown voltage high, and a fine stripe structure is adopted to make the maximum frequency of oscillation high. As a result, the gate-drain breakdown voltage of 300 V, the gate-source breakdown voltage of 70 V, and the maximum frequency of oscillation of 700 MHz are obtained. The maximum output power of 216 W with 7.5-dB gain and 55- percent drain efficiency is obtained at 100 MHz without a thermal runaway from an amplifying SIT with four pellets mounted in a single package.