Fluorine Incorporation and Annealing Properties of a-Si, Ge:H, F Alloys Studied by Elastic Proton Scattering and Ir Absorption

Abstract

ABSTRACTWe report precise measurements of the fluorine content cF in amorphous silicongermanium alloy films (a-Si, Ge:H, F). The films were prepared by r.f. or d.c. glow discharge deposition. The fluorine concentration was measured by elastic scattering (NES) of 12 MeV protons and by IR absorption spectroscopy. Films measured by NES serve as calibration standards for other measurement techniques. Using the NES measurements, we update the published calibration coefficient for IR measurements for cF ranging from 0 to 10 at.%. The annealing properties up to 700°C of a-Si, Ge:H, F were studied by the gas evolution technique and by IR spectroscopy. Above 300°C the Si-F absorption peak decreases while the peak due to SiF4 molecules increases. No significant loss of F from the alloy films seems to occur up to 700°C.