Study of strain in partially relaxed Ge epilayers on Si(100) substrate

(整期优先)网络出版时间:1999-01-11
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Geepilayersofdifferentthicknessesaregrownbymolecular-beamepitaxywithSbasasurfactantonSI(100)substrates,X-raydiffractionillustratesthattheseGethinfilmsarepartiallystrained.andthestrainsdecreasegraduallywithincreasingepilayerthickness,RamanspectrarevealadownwardshiftoftheGe-Gemodepeakastheepilayerthicknessincreases.Intheregionsofhighstrain,therelationshipbetweentheRamanshiftofthismodeandthestraininthepartiallyrelaxedsamplesisconsiderablydifferentfromthelinearrelationshipreportedbefore,whichismainlyattributedtothespatialconfinementeffectofphononsinananocrystal.