Analysis of x-ray diffraction as a probe of interdiffusion in Si/SiGe heterostructures

Autor: D. B. Aubertine, S. Brennan, Nevran Ozguven, Paul C. McIntyre
Rok vydání: 2003
Předmět:
Zdroj: Journal of Applied Physics. 94:1557-1564
ISSN: 1089-7550
0021-8979
DOI: 10.1063/1.1589600
Popis: We investigate numerical simulations that utilize a nonlinear interdiffusion solver and dynamical x-ray diffraction calculations to predict the local composition evolution in low Ge concentration Si/SiGe superlattices and their diffraction patterns during annealing. Superlattice satellite peak decay rates are compared with experimentally measured values and simulated diffraction patterns are matched directly to data with good success. The simulations are used to test the sensitivity of x-ray diffraction to various uncertainties commonly encountered when measuring interdiffusion at Si/SiGe interfaces. It is found that the most serious errors result from variations in the Ge content across the surface of the wafer. For example, the resolution limit of most experimental techniques used to measure Ge concentration in a SiGe film is ±1 at. %, for a film with 11% mean Ge concentration annealed for 5 h at 870 °C, this level of error will cause the observed interdiffusivity values to deviate by −25% or +50%. The ...
Databáze: OpenAIRE