Abstract
A Ga/sub 0.51/In/sub 0.49/P/GaAs DHBT with a heavily doped (1/spl times/10/sup 19/ cm/sup /spl minus/3/) narrow base (8 nm) grown by gas source molecular beam epitaxy and fabricated by simple wet chemical etching was demonstrated for the first time. A variable "N" shape negative differential resistance (NDR) controlled by base current was observed in the common-emitter current-voltage characteristics of this device at room temperature. A maximum peak-to-valley current ratio of 1/spl times/10/sup 7/ and a maximum current gain of 83 were achieved at room temperature. The largest peak-to-valley current ratio (1/spl times/10/sup 7/) achieved is, to our knowledge, the highest reported value to date. The NDR characteristics were explained by the base resistance effect.