Ga₂O₃MOSFETs Using Spin-On-Glass Source/Drain Doping Technology

We report the first demonstration of source/drain (S/D) doping using tin (Sn) doped spin-on-glass (SOG) on Ga2O3power MOSFET. The effectiveness of SOG doping is verified by a comparative experiment on semi-insulating Ga2O3substrates. A specific contact resistance of ρc= 2.1±1.4×10-5Ω·cm2is obtained to the SOG doped layer. The thermal diffusion behavior of Sn in Ga2O3is investigated as well. MOSFETs with SOG S/D doping is fabricated on 200-nm epitaxial Ga2O3layer with an average effective doping of 2×1017/cm3. An increased peak output drain current density of 40 mA/mm is achieved due to reduced S/D resistance. The maximum transconductance (gm) is extracted to be 1.23 mS/mm for a device with Lg= 2μm. The device also shows a large ON/OFF ratio of 108and breakdown voltage of 382 V.