Breakdown of crystallinity in low-temperature-grown GaAs layers
Breakdown of crystallinity in low-temperature-grown GaAs layers
复制标题
低温生长 GaAs 层结晶度的破坏
DOI：
10.1063/1.104990
复制
发表时间：
1991
影响因子：
4
通讯作者：
A. Calawa
中科院分区：
文献类型：
--
作者：
Z. Liliental;W. Świder;K. Yu;J. Kortright;F. Smith;A. Calawa
使用透射电子显微镜、双晶X射线摇摆曲线和粒子诱导X射线发射，对在180 ° C和210 °C之间通过分子束外延沉积的生长GaAs层的结构质量变化进行了系统研究。我们发现晶体质量与生长温度在200 °C附近有很强的相关性。晶格参数和层中掺入的As量在较低的生长温度下增加。在超过一定的生长温度依赖性层厚度之后，形成大密度的金字塔型缺陷，其在最低生长温度下导致结晶度的破坏和柱状多晶生长。晶格膨胀归因于层中过量的As。对结晶度的破坏机理进行了讨论。
A systematic study of the change in structural quality of as‐grown GaAs layers deposited at temperatures between 180 and 210 °C by molecular beam epitaxy was performed using transmission electron microscopy, double‐crystal x‐ray rocking curves, and particle‐induced x‐ray emission. We found that the crystal quality was correlated strongly with growth temperature near 200 °C. The lattice parameter and the amount of As incorporated in the layer were observed to increase at lower growth temperatures. After exceeding a certain growth‐temperature‐dependent layer thickness, large densities of pyramidal‐type defects are formed, which at lowest growth temperature result in the breakdown of crystallinity and in columnar polycrystalline growth. The lattice expansion is ascribed to the excess As in the layers. The mechanisms of breakdown of crystallinity are discussed.