窒化ガリウム系III族窒化物半導体のヘテロエピタキシー(<小特集>格子不整合系のヘテロエピタキシー)

抄録

Issues of the heteroepitaxy of group III nitrides, especially heteroepitaxy of nitrides on highly lattice-mismatched substrates using a buffer layer and heteroepitaxy of nitrides on GaN is discussed. In spite of the large lattice-mismatch between nitrides and sapphire, high quality nitrides have been obtained. Growth process of the group III nitride on sapphire by using a buffer layer was understood by in-situ observation of the reflection high-energy electron diffraction from the epitaxially grown GaN on sapphire by molecular beam epitaxy. It is also found that nitride alloys grown on thick GaN was coherently grown even though the thickness exceeds the critical layer thickness.