Epitaxial Growth Of High Quality In_xGa_1-xAs Films On Si Substrates

With the development of technology, the infrared detectors and solar cells prepared byHgxCd1-xTe and Ge respectively in terms of performance can not meet people’s requirements.InxGa1-xAs materials which has good stability, small effective mass, high electron mobility,high peak drift velocity, high optical absorption coefficient and other advantages, is applied toshortwave infrared detectors and multi-junction solar cells. It has achieved great results untilnow. A series of studies on the epitaxial growth of InxGa1-xAs films on Si substrates has beenmade in order to prepare high-quality of InxGa1-xAs optoelectronic devices in this paper.First, In0.55Ga0.45As films without using a buffer layer, with In0.4Ga0.6As low temperaturebuffer layer and In0.4Ga0.6As high temperature buffer layer are prepared on Si substrates andare tested by XRD, SEM, AFM. It is found that In0.4Ga0.6As low temperature buffer layerand In0.4Ga0.6As high temperature buffer layer are conducive to improving the quality ofIn0.55Ga0.45As films, and In0.55Ga0.45As films prepared on the the low-temperature bufferlayer has higher and better quality. By combining In0.4Ga0.6As low temperature buffer layerand annealing, the quality of In0.55Ga0.45As films improves effectively. Then, the optimalannealing process which low-temperature is360℃, the thickness of the buffer layer isslightly higher than the critical thickness, the annealing temperature is540℃, and theannealing time is20minute single is derived. When the change of the In content in gradedbuffer layers is too large, the quality of In0.55Ga0.45As film is poor.Next, In0.2Ga0.8As films, In0.28Ga0.72As films and In0.35Ga0.65As films are grown and thequality of the films is good. However, when In0.3Ga0.7As films are grown on them, it is foundthat In0.3Ga0.7As films grown on In0.28Ga0.72As films has better quality. The reason is thatwhen y is smaller than x and close to it, high quality InxGa1-xAs films prepared on InyGa1-yAsbuffer layer is got.In summary, the optimal buffer layer technology and suitable growth temperature havebeen obtained through the epitaxial growth of In0.55Ga0.45As films and In0.3Ga0.7As films,which provides guidance to enhance the quality of InxGa1-xAs(0≤x≤1) films.