Investigation of the Novel Characteristics of Widebandgap Semiconductor Materials Grown by Multi-Phase Epitaxy

采用分子束外延的方法对多相结构进行聚焦和生长。并进行了理论分析。该结构生长在GaAs衬底上，而GaAs衬底是各种器件结构的常规材料。ZnCdS最初被认为是多相结构的候选材料，因为ZnS和CdS都具有锌闪锌矿结构和纤锌矿结构。这种材料的另一个优点是GaAs和ZnCdS之间的晶格匹配是可能的。理论计算中还考虑了与InP衬底匹配的其他材料体系晶格。MBE和MOCVD生长的ZnCdS薄膜的晶体结构可以调整，通过改变生长参数可以形成锌闪锌矿结构和纤锌矿结构。无论衬底表面排列如何，即（001）、（111）A和（111）B表面，都可以控制晶体结构。4.5. 提出了x射线phi扫描，并证明它是一种简单而有效的技术来区分这两种结构。ZnCdMgOSSe也被认为是一种可以与InP晶格匹配的多相结构材料。

Multi-phase structures were focused and the layer was grown by molecular beam epitaxy. Theoretical approach was also performed.The structure was grown on the GaAs substrate which was a conventional material for the various device structures. ZnCdS was initially focused for the candidate of the multi-phase structure since both ZnS and CdS exhibit Zincblende structures as well as Wurtzite structures. The other advantage of this material is that the lattice matching between GaAs and ZnCdS is possible.Other materials system lattice match to the InP substrate was also considered from the theoretical calculation.1. The crystal structure of ZnCdS epilayers grown by MBE or by MOCVD can be tuned, and zincblende structures as well as wurtzite structures can be formed by changing the growth parameters.2. The crystal structre can be controlled regardless of the substrate surface arrangement, namely (001), (111)A, and (111)B surfaces.3. 4.5. X-ray phi-scan was proposed and shown that it was a simple and powerful technique to distinguish the two structures.6.7. ZnCdMgOSSe was also considered as a multi-pahse structure materials which can be lattice match to InP.