UMOSFETs in 4H-SiC having both trench oxide protection and junction termination extension are reported for the first time. Devices are fabricated with and without counter-doped channels. Blocking voltages and specific on-resistances are 3,360 V and 199 mOmega-cm(2) for doped-channel FETs and 3,055 V and 121 mOmega-cm(2) for FETs without doped channels. These blocking voltages are believed to be the highest reported to date for UMOSFETs in SiC.