DLTS Study of Emission and Capture Processes in InAlGaN/GaN HEMT Structures for 5G

This contribution deals with a Deep Level Transient Spectroscopy study of emission and capture processes in innovative HEMT structures based on InAlGaN/GaN, grown on N ⁺ doped SiC substrates with a SI epitaxial SiC layer and AlGaN back-barrier. Three different gate types (Schottky, FAT FET and GTLM) were examined. The attention was focused on identified deep energy levels and possible origins compared to various measurement conditions and the gate types. Arrhenius evaluations confirmed traces of Ga-vacancies, dislocations, self-donors associated with the Ga interstitial impurities. Measured DLTS spectra validated an excellent quality of the growth process.