| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a high-quality semiconductor crystal independent of a base substrate. <P>SOLUTION: A seed layer which consists of a GaN layer 103 (a second layer of the seed layer) and an AlN buffer layer 102 (a first layer of the seed layer) is formed on a sapphire substrate 101. The surface of the seed layer is etched into a stripe geometry having a stripe width (the seed layer width S) nearly equal to 5 μm, a wing width W nearly equal to 15 μm, and a depth of about 0.5 μm. After the etching, mesas having a nearly rectangular cross-sectional shape are formed, and the remainder of erosion having the multilayer seed layer in their flat top parts are disposed at a cycle L nearly equal to 20 μm, exposing part of the sapphire substrate 101 in a valley of each wing. The ratio S/W of the seed width to the wing is preferably about 1/3 to 1/5. Then, a semiconductor crystal A is grown to 50 μm or larger, and then separated from the base substrate to obtain a high-quality monocrystal independent of the base substrate. <P>COPYRIGHT: (C)2003,JPO |
