GaN Epitaxial Layer Dislocation Characterization Using ECCI and TEM

Gallium nitride (GaN) is a representative material of the third-generation semiconductor. The growth of GaN heteroepitaxial layers on substrates often leads to dislocations due to lattice mismatch. This paper presents a comprehensive characterization method of these defects using two kinds of electron microscopes, which are commonly available in analytical laboratories. Specifically, we used the electron channeling contrast imaging (ECCI) method based on a dual beam electron microscope system to observe dislocations from the sample surface. We discussed key parameters for acquiring optimal ECCI images and subsequently prepared planar and cross-section lamella samples for analysis at the nano-scale level using transmission electron microscopy (TEM). Our study provides valuable insights into GaN dislocation characterization utilizing two types of electron microscopes, while also discussing image conditions that can serve as a useful reference for semiconductor researchers and engineers conducting similar investigations.