Abstract: The method relates to the production of a very thin insulating or weakly-doped layer in the immediate neighborhood of a highly-doped layer within the body of a semiconductor structure designed to operate in the microwave range. For instance a P.sup.+ I N.sup.+ structure is obtained in an N.sup.+ -doped gallium arsenide substrate, by implanting a P.sup.+ - layer using beryllium ions. An insulating layer is spontaneously formed between the highly-doped layers. Using beryllium, the thickness is effectively of the order of one-tenth of a micron. In another example, an avalanche diode of high efficiency, made of gallium arsenide for microwave operation, having a P.sup.+ N.sup.- N.sup.+ N N.sup.+ structure is obtained wherein the layer N.sup.- is the thin weakly-doped layer in the immediate neighborhood of a highly-doped layer (N.sup.+), which is substantially as thin as the N.sup.- layer in this particular case.

Abstract: A method of making a semiconductor device which has regions of differing type and/or degree of conductivity includes the use of a multi-layer masking coating on selected regions of a body of semiconductor, and a mono-layer masking coating on other selected regions. Ion implantation together with chemical diffusion is used with a single photoresist mask to create regions of both relatively high and relatively low conductivity of one type. A second photoresist mask may be used with ion implantation and chemical diffusion to produce regions of opposite type conductivity with differing degrees of conductivity.

Abstract: A homogeneously doped p-conductive semiconductor material is produced by irradiating a desired semiconductor material with .gamma.-photons which trigger nuclear reactions within such irradiated material to form dopant atoms therein.