A method of producing a silicon carbide insulated gate device that is particularly suited for high power, high field or high temperature operation is disclosed. The method comprises providing a layer of silicon dioxide (12) on a portion of silicon carbide (11) and providing on the layer of silicon dioxide a layer of an insulating material (13), other than silicon dioxide, with a thickness that is greater than the thickness of the silicon dioxide layer and with the insulating material having a dielectric constant higher than the dielectric constant of silicon dioxide. A gate contact (14) is deposited on the layer of the insulating material. A thickness of the silicon dioxide layer represents between 0.5 and 33% of an insulation structure comprising the silicon dioxide layer and the layer of insulating material.