Epitaxial wafer quality versus substrate quality

The effect of various InP substrates properties on epitaxial layer quality was investigated. From the results of experiments on MOCVD, we found that the average haze of epitaxial layer surfaces measured by surfscan can be reduced by using substrates with optimum surface mis-orientation angles of 0.05-0.10 degrees. Our experiments on MBE also showed a similar tendency. Furthermore it was found that appropriate treatment of substrates prevents slips on the periphery of epitaxial wafers.