Atomic Imaging of Atomic H Cleaning of InGAs and InP for ALD

Abstract

Air exposed III-V surfaces nearly always have electronic defects which prevent full modulation of the Fermi level thereby impeding their use in practical semiconductor devices such as metal oxide field effect transistors (MOSFETs). For a high speed device, the air induced defects and contaminants need to be removed to reduce trap states while maintaining an atomically flat surface to minimize interface scattering thereby maintaining a high carrier mobility. Using in-situ atomic scaling imaging with scanning tunneling microscopy, a combination of atomic hydrogen dosing, annealing and trimethyl aluminum dosing is observed to produce an ordered passivation layer on air exposed InGaAs(001)-(4×2) surface with only monatomic steps.