| 摘要 |
<p>The invention relates to a substrate for epitaxy, especially for preparation of nitride semiconductor layers. Invention covers a bulk nitride mono-crystal characterized in that it is a mono-crystal of gallium nitride and its cross-section in a plane perpendicular to c-axis of hexagonal lattice of gallium nitride has a surface area greater than 100 mm<SUP>2</SUP>, it is more than 1.0 mum thick and its C-plane surface dislocation density is less than 10<SUP>6</SUP>/cm<SUP>2</SUP>, while its volume is sufficient to produce at least one further-processable non-polar A-plane or M-plane plate having a surface area at least 100 mm<SUP>2</SUP>. More generally, the present invention covers a bulk nitride mono-crystal which is characterized in that it is a mono-crystal of gallium-containing nitride and its cross-section in a plane perpendicular to c-axis of hexagonal lattice of gallium-containing nitride has a surface area greater than 100 mm<SUP>2</SUP>, it is more 1.0 mum thick and its surface dislocation density is less than 10<SUP>6</SUP>/cm<SUP>2</SUP>. Mono-crystals according to the present invention are suitable for epitaxial growth of nitride semiconductor layers. Due to their good crystalline quality they are suitable for use in opto-electronics for manufacturing opto-electronic semiconductor devices based on nitrides, in particular for manufacturing semiconductor laser diodes and laser devices. The a.m bulk mono-crystals of gallium-containing nitride are crystallized on seed crystals. Various seed crystals may be used. The bulk mono-crystals of gallium-containing nitride are crystallized by a method involving dissolution of a gallium-containing feedstock in a supercritical solvent and crystallization of a gallium nitride on a surface of seed crystal, at temperature higher and/or pressure lower than in the dissolution process.</p> |
