Characterization Of Si1-xGex Epilayer Thickness, Ge and Doped BoronConcentration with UV-Vis-IR Spectroscopic Ellipsometer

摘要

Spectroscopic Ellipsometry (SE) is a non contact, non destructivernapproach based on the change of polarisation of light afterrnreflection on a sample. SE allows the precise determination of thernrefractive indices and thicknesses of the films.rnWith UV-Vis-IR spectroscopic ellipsometer, not only epilayerrnthickness and Ge concentration can be obtained with the UV-Visrnchannel, but also p-type dopant concentration with the IR channel.rnIn this presentation, an alloy model will be introduced first tornobtain Ge concentration. The principle to determine dopantrnconcentration and electric properties of the film will be givenrnsecondly. With the advanced SOPRA ellipsometer tool, four typesrnof samples were characterized, which are (a) single SiGe layerrn(Box), (b) SiGe layer with Si cap, ? SiGe layer with graded Gernconcentration and (d) Boron doped SiGe layer