Japanese Journal of Applied Physics · 1990 · 26 citations · 12 references
Natural SciencesMaterials SciencePhysicsCondensed Matter PhysicsSemiconductor MaterialsSolid State PhysicsDefect CharacterizationDefectsDefects In Electronic MaterialsOptoelectronic MaterialsSemiconductor DefectsSemiconductor PhysicsAbsorption SpectraBand GapConduction BandDeconvolutionDefect Energy LevelsDefect StatesGaussian DistributionsPhotocurrent Generation
Gap states in a-SiGe:H alloys were examined by the deconvolution analysis of subgap absorption spectra obtained by the constant photocurrent method. A broad distribution of defect states was found in a-SiGe:H alloys by the analysis postulating a Gaussian distribution of defect states. Analysis postulating two Gaussian peaks suggested that defects in a-SiGe:H can be divided into Si- related and Ge-related types. The energy positions of two defect peaks relative to the conduction band edge were almost constant irrespective of the optical gap of alloy films, and the position of one peak agreed with the defect peak in a-Si:H. The other peak which locates around 0.75 eV below the conduction band edge appeared when Ge was introduced into a-Si:H. The ratio of these two peaks exhibited a fairly good correlation to the Ge/Si ratio of alloys.
12
Density of the gap states in undoped and doped glow discharge a-Si:H
M. Vaněček, J. Kočka, J. Stuchlı́k et al. · Solar Energy Materials · 1983 · 368 citations