Technology for low gate current AlInAs/InP heterojunction FETs

Monolithic integration of pin-FET circuits on InP is a promising technology for low-cost telecommunication photoreceivers. A very low gate leakage current is desirable in the first amplifier stage, and this motivated the present work on InP channels, as an alternative to the more popular InGaAs-based high electron mobility transistor (HEMT) and HFET structures which exhibit gate leakage related to avalanching in the low bandgap channel. Very low gate leakage current in InP channel HFETs has been achieved by careful device processing. The contribution of the gate current noise of the InP HFET is then very low and the level of the total input noise density may be lower than the one measured on InGaAs/InP monolithic photoreceivers (A. Scavennec et al., 1990). The noise measurements are reported