摘要
我们利用分子束外延方法生长了低温ＧａＡｓ薄膜，并应用Ｘ射线双晶衍射、ＴＥＭ等手段对其进行了初步研究．发现原生样品和树底之间存在晶格失配．随着退火温度的上升，晶格失配逐渐消失．ＴＥＭ观察到６００，７００，８５０℃退火后的样品中存在大量的砷沉淀物．沉淀物大致呈球形．砷沉淀物的直径随着退火温度的上升而线性地增大，而密度却随退火温度的上升指数地下降．
Abstract GaAs layers were grown by molecular beam epitaxy at low temper ature(LT-MBE GaAs) and studied by X-ray double crystals diffraction and TEM.We have observed that as-grown LT-MBE GaAs layer has a 0.14% increase in lattice parameters, the lattice mismatch decreases with increasing annealing temperature.TEM showed there were arsenic precipitates in annealed samples. Average diameter of arsenic precipitates in LT-MBE GaAs increases linearly with increasing annealin temperature, and density decreases exponentially with increasing annealing temperature.
关键词
分子束外延
砷化镓
薄膜
Annealing
Molecular beam epitaxy
Semiconducting films
Thin films
