Back-Gated Phototransistor Fabricated from Low Temperature InP Grown Directly on Amorphous Gate Oxide

One of the major challenges for realizing 3D integrated circuits is the ability to integrate single crystal semiconductor devices on the back-end of functional device layers within a thermal budget of ~400°C. While traditional III-V growth processes such as MOCVD and MBE would give polycrystalline growth on amorphous substrates, it has been demonstrated in some of the previous works [1]–[4], that we can achieve single crystal compound semiconductor growth on diverse amorphous substrates using the TLP (templated liquid phase) approach. In this work, we report for the first time (to the best of our knowledge), the device performance of a back-gated phototransistor with the InP channel grown by TLP directly on the gate oxide at 300°C, and entirely fabricated with all processing steps at or below 300°C.