The BNR diode, a current-controlled negative-resistance device

The bonded NR (negative-resistance) diode is a current-controlled negative-resistance device, fabricated in a similar manner as conventional gold-bonded diodes. Switching times of the device are a few nanoseconds. The I-V characteristic can be strongly controlled by magnetic fields and by illumination. Under continuous operation, magnetic sensitivity up to about 2.7 mv/gauss was observed under dc conditions, decreasing exponentially in an ac magnetic field above 2-3 kc, and disappearing around 25 kc. The sensitivity of the turnover voltage to illumination at a wavelength of 1.4 µ was found to be of the order of 10 mv/µW. The electrical and optical characteristics can be explained on the basis of Gunn\´s avalanche injection model. The magnetic sensitivity and an effect of the diode length on its I-V characteristics are compatible with lifetime modulation in the bulk material. Possible applications of the device as a magnetic and optical sensor are discussed, and an analysis of the device as an active circuit element utilizing its negative resistance is presented.