BS ISO 5618-1:2023

Fine ceramics (advanced ceramics, advanced technical ceramics). Test method for GaN crystal surface defects. Classification of defects | Status: Current

1 Scope This document gives a classification of the dislocations and process-induced defects, from among the various surface defects, that occur on single-crystal gallium nitride (GaN) substrates or single-crystal GaN films. It is applicable to the dislocations and process-induced defects exposed on the surface of the following types of GaNsubstrates or films:

• — single-crystal GaNsubstrate;
• — single-crystal GaN film formed by homoepitaxial growth on a single-crystal GaNsubstrate;
• — single-crystal GaN film formed by heteroepitaxial growth on a single-crystal aluminium oxide (Al2O3), silicon carbide (SiC) or silicon (Si) substrate.

It is not applicable to defects exposed on the surface if the absolute value of the acute angle between the surface normal and the c-axis of GaN is ≥ 8°.