Scaling AlGaN/GaN High Electron Mobility Transistor Structures onto 200-mm Silicon (111) Substrates through Novel Buffer Layer Configurations

摘要

Crack-free and low-bow (< 50 μm) AlGaN/GaN high electron mobility transistor (HEMT) structures are grown on 200-mm diameter Si(111) substrates by using three different buffer layer configurations: (a) Thick-GaN/3 × {Al_xGa_(1-x)N}/AlN, (b) Thin-GaN/3 × {Al_xGa_(1-x)N}/AlN, and (c) Thin-GaN/AlN. Optical, structural, and electrical properties of these AlGaN/GaN HEMT structures are reported. The effects of buffer layer stacks (i.e. thickness and content) on defectivity, stress, and two-dimensional electron gas (2DEG) mobility and concentration are studied. We show that the in-plane stress type and magnitude significantly affect the 2DEG characteristic, suggesting the importance of optimal buffer layer configurations for AlGaN/GaN HEMTs on Si(111) substrates.