METHOD FOR PREPARING SINGLE CRYSTAL OF III GROUP ELEMENT NITRIDE AND TRANSPARENT SINGLE CRYSTAL OF III GROUP ELEMENT NITRIDE PREPARED THEREBY

摘要

In an embodiment, gallium, lithium and sodium are placed in a BN crucible and are molten in a nitrogen atmosphere at a temperature of 800°C, under a low pressure as well as 30 atm (ca. 0.3 MPa), and then a single crystal is grown for 96 hours. The resultant gallium nitride single crystal is colorless and transparent with no blackening, exhibits almost no dislocation and has high quality, as shown in a photomicrograph of Fig. 2, and has a maximum diameter of 2 cm or more. An alkali metal other than sodium (except Li and Na) or an alkaline earth metal can be added in place of sodium or in addition to sodium.