Abstract A semiconductor device and a method for making the same. The device includes a semiconductor body having at least one PN junction created by the diffusion of impurities into the body. The device further includes an intermediate layer arranged on the surface of the semiconductor body and made of a material having a higher diffusion constant for the diffused impurities than the semiconductor body. The method includes the steps of applying the intermediate layer to the semiconductor body, applying a masking layer, having a diffusion window opening, to the intermediate layer and diffusing the impurities into the semiconductor body, through the diffusion window and the intermediate layer.
The method defined in claim 1, wherein said impurities are selected from group IIIa of the periodic table.
Claim 2
Dependent Claim
20 words
The method defined in claim 2, wherein said intermediate layer is silicon dioxide and said masking layer is silicon nitride.
Claim 3
Dependent Claim
32 words
The method as defined in claim 1 wherein said intermediate layer covers the portion of said surface of said semiconductor body underlying said opening in said masking layer during said diffusion step.
Claim 4
Dependent Claim
38 words
The method as defined in claim 1 wherein when said method is used in the production of a transistor, said defined portion of one surface of said semiconductor body corresponds to the cross-sectional area of the base zone.
Claim 5
Dependent Claim
51 words
The method as defined in claim 1 wherein when said method is used in the production of a transistor whose collector zone is electrically insulated from the remainder of said semiconductor body, said defined portion of one surface of said semiconductor body corresponds to the cross-sectional area of the collector zone.