12 where a central portion of insulating layer 14 is then etched away exposing n substrate region 12 a metallic layer 16 which forms the anode of the prior art schottky barrier device is deposited into the opening created by the etchant and possibly overlaps a portion of insulating layer 14 as illustrated in fig1 many different metals and alloys may be used as layer 16 where nickel silicide is considered to be one alternative it is to be understood that a schottky barrier diode may also be formed with a p type substrate region and the use of an n type region throughout the present discussion is considered to be exemplary only as is well known a schottky barrier diode differs from a conventional diffused p n junction diode in that schottky barrier diodes are metal semiconductor junction devices where schottky barrier 18 is illustrated in fig1 as previously discussed prior art schottky barrier diodes attempted to improve the reverse operating characteristics by increasing the reverse breakdown voltage which is related to edge breakdown effects this was accomplished by the inclusion of an annular guard ring illustrated in fig1 in a cross sectional view as p type diffusion 20 where the edges which.