Abstract: Ceramic radomes are fabricated using a method which reduces the dielectric losses of the ceramic material. A Si.sub.3 N.sub.4 ceramic powder is mixed with a suitable densification aid and then sintered to form a dense ceramic having a glassy phase. Silicon dioxide is then provided on the surface of the ceramic by packing it in silicon dioxide powder or by heating it in air to oxidize its surface. The ceramic and silicon dioxide are heated at a temperature sufficient to cause diffusion of impurities and additive cations from the glassy phase into the silicon dioxide. The surface of the ceramic is then ground to remove pits and to shape the ceramic into a radome.

Abstract: A metal-semiconductor field-effect transistor (MESFET) is provided with a p-type region adjacent the n-type region under the drain contact. Holes injected from this p-type region compensate the negative space charge region at the channel to substrate interface, thus minimizing considerable substrate effects.