STUDY OF THE EFFECT OF DEPOSITION OR ANNEALING TEMPERATURE ON THE AU/GASB(100) INTERFACE FORMATION BY LOW-ENERGY-ELECTRON DIFFRACTION AND AUGER OR ELECTRON LOSS SPECTROSCOPIES

Auger electron spectroscopy (AES), energy electron loss spectroscopy (EELS) and low energy electron diffraction (LEED) are used to precise the interaction of gold with GaSb(100) surfaces grown on GaSb substrates by molecular beam epitaxy (MBE). After the growth, the GaSb layers, produced in the laboratory, were transferred by the mean of an ultra vacuum lock chamber, into an other ultra vacuum chamber devoted to the deposit of gold and to the physical studies. Measurements were first performed on the clean surfaces and then on surfaces covered by increasing amounts of gold (6 x 10(13) - 1.8 x 10(16) atoms cm(-2)) deposited on substrates brought at room temperature or at low temperature (220 K). The samples were then studied during the annealing up to 520 K. The results show that, at the beginning of the deposition, gold was adsorbed on the MBE GaSb(100) surface. When the gold coverage increases and becomes higher than 10(15) atomes cm(-2), Au diffuses into the bulk and forms alloys.