Semiconductor device and method of producing it

Claim 1

A SEMICONDUCTOR DEVICE COMPRISING A HIGHLY DOPED SEMICONDUCTOR BODY, AN EXTENDED AREA ELECTRODE FOR SAID BODY, A THIN COATING ON SAID ELECTRODE OF A METAL CONTAINING AN IMPURITY THAT WILL PRODUCE A CONDUCTIVITY OPPOSITE TO THAT OF SAID BODY, SAID BODY HAVING A CROSSSECTION AT ONE END SMALLER THAN THAT OF THE BODY AWAY FROM SAID END AND A VERY SMALL SURFACE AREA AT SAID END IN CONTACT WITH THE COATING ON SAID ELECTRODE, THE AREA OF SAID COATING AND ELECTRODE EXTENDING BEYOND SAID CONTACT AREA, AN ALLOYED PORTION JOINING SAID ELECTRODE WITH SAID BODY AT SAID SMALL SURFACE AREA, A P-N JUNCTION IN SAID ALLOYED PORTION IN CLOSE PROXIMITY TO THE AREA OF CONTACT, A SECOND EXTENDED AREA ELECTRODE, A THIN COATING ON AN EXTENDED AREA OF SAID SECOND ELECTRODE OF A METAL CONTAINING AN IMPURITY THAT WILL PRODUCE THE SAME CONDUCTIVITY AS THE SEMICONDUCTOR BODY, SAID BODY HAVING ANOTHER SURFACE AREA IN CONTACT WITH THE COATING ON SAID SECOND ELECTRODE, A SECOND ALLOYED PORTION JOINING SAID LAST-MENTIONED ELECTRODE WITH SAID BODY TO FORM AN OHMIC CONTACT BETWEEN SAID BODY AND SAID SECOND ELECRODE, SAID ELECTRODES BEING WAFERSHAPED AND SAID SEMICONDUCTOR BODY BEING OF HIGHLY DOPED P-TYPE GERMANIUM, THE METAL COATING ON THE ELECTRODE ADJACENT THE P-N JUNCTION BEING AN ALLOY OF APPROXIMATELY 95 PERCENT TIN AND 5 PERCENT ARSENIC AND THE N LAYER OF SAID JUNCTION BEING A RECRYSTALLIZED REGION OF SAID ALLOY ON SAID BODY.