Nitridation of Si (100) made by radio frequency plasma as studied by <i>i</i> <i>n</i> <i>s</i> <i>i</i> <i>t</i> <i>u</i> angular resolved x-ray photoelectron spectroscopy

Abstract

X-ray photoelectron spectroscopy with variable takeoff angles has been used to study the nitridation of Si(100). The air-oxidized layer on the silicon film has been cleaned off by an Ar radio frequency (rf) plasma, and nitridation was obtained at temperatures around 400 °C in a rf plasma of a NH3 (5%)-N2(95%) mixture. N(1s) and Si(2p) photoelectrons lines have been analyzed as function of the angle θ between the surface of the sample and the detector slit at each step of nitridation to obtain depth profile. These lines have both been decomposed into two components due, on one hand, to the Si–N and the metallic bonds and, on the other hand, to the chemisorbed nitrogen and the N–Si bond. From the integrated intensities of these lines, concentration dependencies on depth and nitridation time have been studied; a nitridation kinetics has been deduced.