EPITAXIAL WAFER

摘要

PURPOSE:To obtain an epitaxial wafer suitable for LED manufacture of high output and with easy structure by continuously changing mixed crystal ratio of aluminum arsenide from a first area to a second area while in a p-type mixed crystal layer the first area of pn-junction to a prescribed range has a direct transition type band structure and the residual second area has a indirect transition type band structure. CONSTITUTION:Electrical conductive type of a substrate 1 generally uses p-type GaAs in which zinc is doped. A layer 2 has a p-type GaAlAs mixed crystal one and the other layer 4 has a n-type GaAlAs mixed crystal one of indirect transition type band structure. AlAs mixed crystal ratio indicates x value when GaAlAs is shown as (AlAs)x(GaAs)1-x. The layer 4 needs that AlAs mixed crystal ratio indicates approximately 0.45