Enhancing Electrical Properties of Selectively Grown In-Plane InAs Nanowires using InGaAs Buffer and Capping Layers

TL;DR

This study demonstrates that adding InGaAs buffer and capping layers to InAs nanowires significantly improves their electrical properties, such as electron mobility and phase coherence length, by reducing defects and disorder.

Contribution

It introduces a novel method of using InGaAs buffer and capping layers to enhance the electrical quality of selectively grown InAs nanowires.

Findings

Electron mobility nearly tripled with InGaAs layers

Phase coherence length doubled with InGaAs layers

Wider growth selectivity window achieved using atomic hydrogen

Abstract

In-plane semiconductor nanowires with complex branched geometries, prepared via selective area growth (SAG), offer a versatile platform for advanced electronics, optoelectronics, and quantum devices. However, defects and disorder at the interfaces and top surfaces of the nanowires can significantly degrade their electrical properties. One effective method to mitigate these issues is the incorporation of buffer and capping layers. In this work, we achieved a wider growth selectivity window of InGaAs in the presence of atomic hydrogen (H) and employed it as buffer and capping layers for SAG InAs nanowires to enhance their electrical properties. Hall measurements on InAs nanowires, with and without InGaAs buffer and/or capping layers, revealed that incorporating closely lattice-matched InGaAs buffer and capping layers to InAs nanowires nearly tripled the electron mobility and doubled the phase coherence length compared to nanowires without these layers. These findings demonstrate that the use of InGaAs buffer and capping layers is a crucial strategy for significantly enhancing the quality of InAs nanowires, unlocking their full potential for high performance electronics and quantum devices.