Growth of 100-mm-diameter AlGaN/GaN heterostructures on sapphire substrates by MOVPE

For the purpose of the practical use of GaN-based electronic devices, we demonstrated the growth of 100-mm-diameter AlGaN/GaN heterostructures on c-face sapphire substrates by metalorganic vapor phase epitaxy (MOVPE). The obtained films have specular surface, good crystal quality and good uniformity of the Al composition across the entire epitaxial wafer. These epitaxial wafers showed a relatively high electron mobility, 1320 ± 80 cm²/Vs with the sheet carrier concentration of 8.4 ± 0.5 × 10¹²/cm ³ at room temperature, across the entire epitaxial wafer. High-electron-mobility transistors (HEMTs) fabricated on the 100-mm-diameter epitaxial wafer also exhibited good dc characteristics. Typical values of the peak extrinsic transconductance and the maximum drain current density were 200 mS/mm and 534 mA/mm, respectively, for the device with the gate length of 2.0 μm and the gate width of 15.0 μm.