A new method used for solution epitaxial of Ga

1-

x

Al

x

As is reported here.An epitaxial layer of 3-4μ at the top of the epitaxial surface with uniform

x

composition

even in increasing tendency along growth direction

is produced by controling cooling rate. The epitaxial surface is naturally perfect only with fewer defects and no machine-damage. It is possible to reduce the production costs and to raise the finished product rate greatly because the procedure is completed in a single epitaxial layer. The devices made by this method have total flux output of 3-6 mlum under 20 mA.The efficiency of this kind of device would further be increased.