Photo effects at the Schottky interface in extraordinary optoconductance

Abstract

Non-uniform optical illuminations near the Schottky interface of Ti/GaAs metal-semiconductor hybrid (MSH) structures induce local photovoltages transverse and lateral to the interface. In these VLSI-compatible, room temperature optical sensors, the optical response of the MSH resistance is directly linked to the Schottky barrier behavior. In order to correlate the interface behavior with the overall heterostructure behavior, quantities such as transverse photovoltage, lateral photovoltage, and resistance are all recorded as a function of laser spot location. The interface's photovoltaic dependence on intensity is consistent with a MSH in which quantum efficiency is independent of optical intensity.

Multifunctional semiconductor micro-Hall devices for magnetic, electric, and photo-detection

“…6,7 Meanwhile, SPVM experiments have focused primarily on the quantum Hall regime to visualise edge channel transport at the sample boundaries. 8,9 Recently, SPVM has been used to image ballistic photocurrents, 10 spin-dependent transverse photovoltages, 11 and metal-semiconductor interface effects 12,13 in GaAs-based microstructures. Meanwhile, InSb 2DEG structures are particularly well suited to sensing applications due to the high RT electron mobility 14,15 of l e < 60 000 cm 2 /V s, exceeded only by that in suspended/encapsulated graphene.…”