III GROUP NITRIDE CRYSTAL AND METHOD FOR PREPARATION THEREOF, AND III GROUP NITRIDE CRYSTAL SUBSTRATE AND SEMICONDUCTOR DEVICE

摘要

A method of manufacturing a group III-nitride crystal includes the steps of: preparing a seed crystal (10), and growing a first group III-nitride crystal (21) on the seed crystal (10) by liquid phase method; wherein in the step of growing a first group III-nitride crystal (21) on the seed crystal (10), rate of crystal growth V H in a direction parallel to a main surface (10h) of the seed crystal (10) is higher than rate of crystal growth V V in a direction vertical to the main surface (10h) of the seed crystal (10). By the manufacturing method, a group III-nitride crystal is obtained, of which dislocation density of a surface parallel to the main surface (10h) of the seed crystal (10) is as low as at most 5 × 10 6 /cm 2 .