STM: Seeing is believing

AbstractIn the last ten years the scanning tunnelling microscope (STM) has completely changed the way in which we look at the surfaces of semiconductor materials. However, due to the conflicting experimental geometries of the two techniques, it is only recently that it has been possible to combine high resolution STM imaging with a full scale MBE system. In this article we demonstrate the application of this technique in obtaining both morphological and atomic resolution images of MBE grown GaAs(001) surfaces and the same surfaces after deposition of Si

Heteroepitaxial Beta-Ga2O3 on 4H-SiC for an FET With Reduced Self Heating

A method to improve thermal management of β-Ga 2 O 3 FETs is demonstrated here via simulation of epitaxial growth on a 4H-SiC substrate. Using a recently published device as a model, the reduction achieved in self-heating allows the device to be driven at higher gate voltages and increases the overall performance. For the same operating parameters an 18% increase in peak drain current and 15% reduction in lattice temperature are observed. Device dimensions may be substantially reduced without detriment to performance and normally off operation may be achieved

Angle-resolved photoemission studies of adsorption on the (100) surfaces of copper and nickel

SIGLEAvailable from British Library Lending Division - LD:D56485/85 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Surface Preparation of InAs (110) Using Atomic Hydrogen

Atomic hydrogen cleaning has been used to produce structurally and electronically damage-free InAs(110) surfaces.  X-ray photoelectron spectroscopy (XPS) was used to obtain chemical composition and chemical state information about the surface, before and after the removal of the atmospheric contamination. Low energy electron diffraction (LEED) and high-resolution electron-energy-loss spectroscopy (HREELS) were also used, respectively, to determine the surface reconstruction and degree of surface ordering, and to probe the adsorbed contaminant vibrational modes and the collective excitations of the clean surface. Clean, ordered and stoichiometric  InAs(110)-(1×1) surfaces were obtained by exposure to thermally generated atomic hydrogen at a substrate temperature as low as 400ºC.  Semi-classical dielectric theory analysis of HREEL spectra of the phonon and plasmon excitations of the clean surface indicate that no electronic damage or dopant passivation were induced by the surface preparation method