Active interface characteristics of heterogeneously integrated GaAsSb/Si photodiodes

Abstract

There is increased interest in the heterogeneous integration of various compound semiconductors with Si for a variety of electronic and photonic applications. This paper focuses on integrating GaAsSb (with absorption in the C-band at 1550 nm) with silicon to fabricate photodiodes, leveraging epitaxial layer transfer (ELT) methods. Two ELT techniques—nanomembrane transfer printing and macro-transfer printing—are compared for transferring GaAsSb films from InP substrates to Si, forming PIN diodes. Characterization through atomic force microscopy and transmission electron microscopy exhibits a high-quality, defect-free interface. Current–voltage (IV) measurements and capacitance–voltage analysis validate the quality and functionality of the heterostructures. Photocurrent measurements at room temperature and 200 K demonstrate the device's photo-response at 1.55 μm, highlighting the presence of an active interface.