Competing detection mechanisms in hot carrier micro-wave diodes

Polarity reversal with d-c bias has been obtained in hot carrier microwave diodes. These diodes, characterized by a one mil diameter junction of phosphorous-doped gold alloyed into a 4 ohm-cm silicon substrate, behave like Schottky barrier diodes under forward bias, but under small reverse bias the sensitivity goes to zero. With further negative bias the polarity or sense of the detected 1KC square-wave modulation at 9.3 GHz changes sign and the sensitivity improves, until it is within 5 to 10 db of the forward bias value.