Engineering Commons^™

Digital Oxide Deposition Of Sio2 Layers For Iii-Nitride Metal-Oxide-Semiconductor Heterostructure Field-Effect Transistors, V. Adivarahan, S. Rai, N. Tipirneni, A. Koudymov, J. Yang, Grigory Simin, M. Asif Khan

Faculty Publications

We present a digital-oxide-deposition (DOD) technique to deposit high quality SiO₂dielectric layers by plasma-enhanced chemical vapor deposition using alternate pulses of silicon and oxygen precursors. The DOD procedure allows for a precise thickness control and results in extremely smooth insulating SiO₂ layers. An insulating gate AlGaN∕GaNheterostructurefield-effect transistor(HFET) with 8nm thick DOD SiO₂dielectric layer had a threshold voltage of −6V (only 1V higher than that of regular HFET), very low threshold voltage dispersion, and output continuous wave rf power of 15W∕mm at 55V drain bias.