| 摘要 |
A nitride semiconductor multilayer structure includes a sapphire substrate having an m-plane principal surface with an off-angle &phgr;, and a mask layer including first and second side surface portions that sandwich each exposed region. In a cross section parallel to the m- and c-axes, points at which the first and second side surface portions meet the principal surface are respectively points A and B, a point at which the first side surface portion intersects a line passing through point B and forming an angle of 58°−&phgr; with the principal surface is C, a distance between a line passing through point C and perpendicular to the principal surface and a line passing through point B and perpendicular to the principal surface is W, and a height of the first side surface portion is H. Then H≧W·tan(58°−&phgr;)). |
