True planar InAs/AlSb HEMTs with ion-implantation technique for low-power cryogenic applications

In this paper, we report the room-temperature and cryogenic properties of true planar 110 nm InAs/AlSb HEMTs fabricated with Ar-ion isolation technology. Device isolation is generally improved and is in particular increased by four orders of magnitude at 6 K compared to 300 K. This results in improved drain current saturation, lower gate leakage current and 23% higher peak transconductance. The RF performance is significantly improved as well, with 47% higher fT (162 GHz) and 72% higher fmax (155 GHz) at the low drain voltage of 0.1 V, compared to room temperature. The overall performance of the fabricated devices shows the suitability of ion implantation for the device isolation at cryogenic temperature. Furthermore, the excellent stability against oxidation and truly planar structure of these devices demonstrate great potential for highly integrated cryogenic millimeter-wave circuits in InAs/AlSb technology with ultra-low power consumption.

► True planar InAs/AlSb HEMTs with ion implantation for device isolation are reported. ► The optimal implantation energy for best isolation was found to be 100 keV. ► The electrical isolation strongly increased when reducing the temperature. ► Overall improvements of the implanted device observed at cryogenic temperature. ► Planar Sb-based HEMTs with very high stability against oxidation are demonstrated.