Adsorption and thermal decomposition of diethyltellurium on GaAs(100)

Adsorption and thermal decomposition of diethyltellurium (DETe) on GaAs(100) have been studied using in situ X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD) techniques. Multilayer adsorption of DETe is achievable at 130 K but adlayer thickness saturates at about 0.80 monolayer at 310 K. DETe is primarily found to adsorb molecularly at 130 K for multilayer coverage. By 150 K the physisorbed layers of DETe desorb leaving only the chemisorbed metalalkyl on the surface. This metalalkyl dissociates before 200 K producing adsorbed tellurium (Te) atoms which in turn interact rather heavily with the surface gallium atoms. Carbons/hydrocarbons resulting from DETe dissociation desorb from the surface by 300 K. Te atoms, on the other hand, remain firmly attached to the surface well after 600 K.