InGaAs/InP Junction Field-Effect Transistors with High Transconductanc

The growth and fabrication of a InGaAMnP junction field- effect transistor using metal organic vapor phase epitaxy is reported for the first time. Very high extrinsic transconductance has been achieved (210 mS/mm for a gate length of 1.5 Fm), by the use of a p-InP buffer layer which allows close to maximum electron velocity in the channel, and by using a self-alignment technique to give very low values of access resistance, typically 0.5 il.mm. InGaAs, lattice-matched to InP, is an important material for optoelectronic devices. Excellent electronic properties (high mobility and high peak electron velocity), make this material suitable for high performance field-effect transistors, while the absorption edge at a wavelength of 1.67 pm means that it is an ideal candidate for photodetectors used in optical communi- cation systems operating in the low-loss windows of silica- based fibers at wavelengths of 1.3 and 1.55 pm. Monolithic integration of photodetector and amplifying electronics is an important step towards very high sensitivity, or low-cost optical receivers. The JFET described in this letter has been designed to facilitate vertical integration with a p-i-n-