利用分子束外延技术,通过RHEED图像演变实时监控薄膜生长状况,采用RHEED强度振荡测量薄膜生长速率,固定Ga源温度、改变In源温度在GaAs(001)基片上外延生长了不同In组分(39%、29%、19%)的InGaAs薄膜。比较RHEED强度振荡以及RHEED衍射图像,发现随着In组分的增加In-GaAs的生长将很快进入三维粗糙表面生长模式,并指出In0.19Ga0.81As和In0.29Ga0.71As薄膜处于(2×3)表面重构相。In0.19Ga0.81As样品进行退火处理后完成STM扫描分析,证实样品为表面原子级平整的In-GaAs薄膜。
A series of InxGa1-xAs films were grown on GaAs(001) substrates over the compositions range from InAs to GaAs(100%,39%,29%,19%,0) by MBE.During the process of growing InxGa1-xAs,the growth rate and status were measured and monitored via RHEED oscillations and patterns respectively.Compared the RHEED oscillations and patterns,the growth mode turned rapidly from 2D to 3D with increasing of In composition.We draw a reasonable assumption to determine the composition of the InxGa1-xAs,and obtained ideal results.For the sample of composition of In0.19Ga0.81As,after growth and subsequent annealing,the STM images confirmed that the surface of this sample was atomically flat and(2×3) reconstructed.