Field controlled semiconductor devices and methods of making them

Claim 1

A METHOD OF MAKING A FIELD CONTROLLED SEMICONDUCTOR DEVICE COMPRISING SURFACE ALLOYING TWO BARRIER-FORMING ELECTRODES UPON COAXIALLY ALIGNED, OPPOSITE SURFACE PORTIONS OF A CRYSTALLINE SEMICONDUCTIVE BODY, SAID ELECTRODES COMPRISING A MATERIAL CAPABLE OF IMPARTING ONE TYPE OF CONDUCTIVITY TO SAID BODY WHEN DISPERSED THEREIN, PLACING A SECOND MATERIAL UPON EXPOSED SURFACE PORTIONS OF SAID BODY, SAID SECOND MATERIAL BEING CAPABLE OF IMPARTING CONDUCTIVITY OF A TYPE OPPOSITE TO SAID ONE TYPE WHEN DISPERSED IN SAID BODY, SAID SECOND MATERIAL HAVING A DIFFUSION COEFFICIENT IN SAID BODY GREATER THAN THE DIFFUSION COEFFICIENT OF SAID ELECTRODE MATERIAL IN SAID BODY, AND HEATING SAID BODY AT A SELECTED TEMPERATURE AND FOR A PERIOD OF TIME SUFFICIENT TO CAUSE SAID SECOND MATERIAL TO DIFFUSE THROUGHOUT A SELECTED REGION THEREOF TO CHANGE THE CONDUCTIVITY CHARACTERISTIC OF SAID REGION THEREBY TO DEFINE A CURRENT PATH REGION IN SAID BODY, SAID CURRENT PATH REGION BEING OF THE INITIAL CONDUCTIVITY CHARACTERISTIC OF SAID BODY AND BEING DISPOSED ENTIRELY DIRECTLY BETWEEN SAID ALLOYED ELECTRODES.