Studies of AlGaN/GaN high-electron-mobility transistors on 4-in. diameter Si and sapphire substrates

AlN buffer layer growth for GaN epitaxy on (111) Si: Al or N first?

“…This is well highlighted by recent progress in terms of material quality figures of merit as well as device operation demonstration [10][11][12]. In particular, the improvement of the growth of (Al,Ga)N/GaN heterostructures on Si(111) substrates has recently given rise to the fabrication of high electron mobility transistor (HEMT) with characteristics comparable to those reported for similar devices obtained from growth on silicon carbide or sapphire [13][14][15][16][17][18]. However, the use of Si as substrate for the epitaxial growth of GaN and related alloys presents specific difficulties related to the very high reactivity of the Si surface especially with nitrogen and group-III species, the large lattice mismatch and the large difference in thermal expansion coefficient with GaN.…”

Electrical characterization of Ni/Al0.09Ga0.91N Schottky barrier diodes as a function of temperature

“…Especially, an improvement in the quality of epitaxial layers grown by metalorganic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE) technologies have made possible the realization of a number of GaN-based devices. Several research groups [6][7][8] demonstrated encouraging operations of high electron mobility transistors (HEMTs) and metal-semiconductors field effect transistors (MESFETs) with outstanding high dc transconductance and high cut-off frequency. Experimental studies of the gate current leakage in AlGaN HEMTs show that the excess gate leakage strongly influences the gate control and power consumption [8].…”

“…Several research groups [6][7][8] demonstrated encouraging operations of high electron mobility transistors (HEMTs) and metal-semiconductors field effect transistors (MESFETs) with outstanding high dc transconductance and high cut-off frequency. Experimental studies of the gate current leakage in AlGaN HEMTs show that the excess gate leakage strongly influences the gate control and power consumption [8]. The noise performance of Al x Ga 1 À x N/GaN HEMTs is also dependent on gate leakage current.…”

Optimization of Ohmic Contact Metallization Process for AlGaN/GaN High Electron Mobility Transistor

“…Most HEMTs are grown on sapphire [4][5][6], silicon [7][8][9], or SiC [10][11][12] substrates. SiC substrates are presently the best choice for epitaxial growth because of their excellent crystal quality and have been used in devices with the highest output power densities.…”