Beyond Thermal Management: Incorporating p-Diamond Back-barriers and Cap-layers into AlGaN/GaN HEMTs

This work explores the use of p-diamond back-barriers and cap-layers to enhance the performance of GaN-based high electron mobility transistors (HEMTs). Diamond can offer a heavily-doped p-type layer, which are complementary to GaN electronics. Self-consistent electro-thermal simulations reveal that the use of p-diamond back-barriers and cap-layers can increase the breakdown voltage of GaN-based HEMTs by four-fold, at the same time that they enhance the 2DEG confinement and reduce short channel effects. These results highlight that p-diamond layers can improve the performance of GaN HEMTs for high-power and high-frequency applications beyond the thermal improvements pursued until now.