Surface etching of InP(100) by chlorine

The cleaning and etching of the InP(100) surface by chlorine gas is investi gated using synchrotron-radiation photoemission spectroscopy. A clean InP s urface with a 4 x 2 confguration is obtained by ion sputtering or chlorine etching, followed by annealing to 650 K. The clean surface obtained by chlo rine etching and annealing is indium-rich with the surface indium atoms sho wing metallic characterics. The chemisorption of chlorine leads to the form ation of various InClx (x = 1-3) and PCl species on the InP surface at 110 K and their corresponding chemical shifts are assigned. The chlorination of the InP surface causes surface band bending by about 0.36 eV at the satura tion coverage. Argon-ion sputtering enhances the surface reactivity so that the sputtered surface can be chlorinated to a higher extent than the clean surface. (C) 1998 Elsevier Science B.V. All rights reserved.