III-V族半導体混晶のエピタキシャル成長に伴う規則化と相分離のモンテカルロシミュレーションによる検討

抄録

It is known that ordered structures appear in III-V semiconductor alloys grown by vapor phase epitaxy. The existence of these ordered phases is unexpected from the equilibrium phase diagram for the bulk III-V alloys. In order to clarify the formation mechanism of the ordered structures in epitaxially grown III-V semiconductor alloys, we have proposed a simple kinetic Ising model for the epitaxial growth and carried out Monte Carlo simulations of the microstructural evolution based on the proposed model. This article is concerned with the CuAu-I (L1₀) and CuPt (L1₁) type ordering in the epilayers grown on exact (001) substrates. The simulated microstructures and their Fourier power spectra are in excellent agreement with those revealed by electron microscopy and diffraction. This suggests that our crystal growth model is quite useful in discussing the ordering kinetics and phase state in epitaxially grown layers. We also refer to the interfacial spinodal decomposition, which often occurs in liquid phase epitaxy.