FREE-STANDING GaN SUBSTRATE, GaN CRYSTAL, METHOD FOR MANUFACTURING GaN SINGLE CRYSTAL AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a non-polar or semi-polar GaN substrate having an improved size and crystal quality.SOLUTION: The free-standing GaN substrate has 0 to 20 degrees of an angle between the normal of a main surface and a m axis. The size of a projection image in the c axis direction is 10 mm or more when the main surface is vertically projected to a M plane. When using a region including a stacking fault and except a portion of the main surface where a distance from a substrate end surface is within 2 mm, as an effective region, a stacking fault density acquired by dividing the total length of the stacking fault existing in the effective region by the area of the effective region is less than 15 cm. The method for manufacturing a GaN single crystal comprises: growing a first GaN crystal using the free-standing GaN substrate as a seed; and growing a second GaN crystal using a part or all of the first GaN crystal as a seed. The method for manufacturing a semiconductor device comprises: preparing the free-standing GaN substrate; and epitaxially growing one or more kinds of nitride semiconductors thereon to form a device structure.SELECTED DRAWING: Figure 1