THE EFFECT OF GERMANE VARIATION ON MICROSTRUCTURE IN POLYCRYSTALLINE SI SI1-XGEX THIN-FILMS GROWN BY RAPID THERMAL CHEMICAL-VAPOR-DEPOSITION - FRACTAL CHARACTERIZATION USING SCANNING PROBE MICROSCOPY/

Scanning probe microscopy (SPM) techniques have been employed to image and characterise polycrystalline thin films of both pure silicon and Si/Si1-xGex. The layers were grown on oxidised silicon substrates usin g a rapid thermal chemical vapour deposition (RTCVD) reactor. Microstr uctural characteristics (roughness and grain size) were measured and t heir dependence on germane content to the gas flow during deposition e lucidated using a range of analysis techniques, including fractal meth ods. By tracking the evolution of cross-over points in the fractal spe ctrum, an estimate for the grain size range can be obtained, which tal lies extremely well with actual topographical measurements.