Method of reducing emitter dip in transistors utilizing specifically paired dopants

Claim 1

A method of manufacturing a semiconductor device comprising: providing an N type collector layer in an N type silicon semiconductor wafer having a substantially flat surface; diffusing an N type impurity having a high energy of combination with vacancies and boron which is a P type impurity material through a first opening in a first insulating layer covering said N type collector layer such that a P type base layer in contact with said N type collector layer having a PN junction extending to said surface is formed, said P type base layer having a substantially uniform P type impurity concentration distribution in the direction of depth of said layer; covering said N type collector layer and said P type base layer with a second insulating layer; forming a second opening in said second insulating layer, said second opening being smaller than said first opening in said first insulating layer; and diffusing phosphorus and arsenic which are N type impurity materials through said second opening in said second insulating layer into said P type base layer so that an N type emitter layer is formed which is in contact with said P type base layer having a PN junction extending to said surface and which constitutes a transistor together with said N type collector layer and said P type base layer.

Claim 2

A method of manufacturing a semiconductor device comprising: providing an N type collector layer in an N type silicon semiconductor wafer having a substantially flat surface; diffusing an N type impurity having a high energy of combination with vacancies and boron which is a P type impurity material through a first opening in a first insulating layer covering said N type collector layer such that a P type base layer in contact with said N type collector layer having a PN junction extending to said surface is formed, said P type base layer having a substantially uniform P type impurity concentration distribution in the direction of depth of said layer; covering said N type collector layer and said P type base layer with a second insulating layer; forming a second opening in said second insulating layer, said second opening being smaller than said first opening in said first insulating layer; and diffusing phosphorus and arsenic which are N type impurity materials through said second opening in said second insulating layer into said P type base layer so that an N type emitter layer is formed which is in contact with said P type base layer having a PN junction extending to said surface and which constitutes a transistor together with said N type collector layer and said P type base layer.

Claim 3

A method of manufacturing a semiconductor device which comprises the steps of: providing an N type collector layer in an N type silicon semiconductor wafer having a substantially flat surface; coating said N type collector layer with a first oxide film layer; forming a first opening in said first oxide film layer such that a portion of the surface of said N type collector layer is exposed; depositing a layer doped with an N type impurity having a high energy of combination with vacancies on said N type collector layer exposed by said first opening; diffusing said N type impurity from said N type impurity doped layer into said N type collector layer; removing said N type impurity doped layer from said N type collector layer; depositing a boron doped layer on said N type collector layer exposed by said first opening; diffusing boron from said boron doped layer into said N type collector layer such that a P type base layer in contact with said N type collector layer having a PN junction extending to said surface is formed; removing said boron doped layer from said N type collector; covering said N type collector layer and said P type base layer with a second oxide film layer; forming a second opening in said second oxide film layer, said second opening being smaller than said first opening in said first oxide film layer; and diffusing phosphorus and arsenic which are N type impurities through said second opening in said second oxide layer into said P type base layer such that an N type emitter layer is formed which is in contact with said P type base layer having a PN junction extending to said surface and which constitutes a transistor together with said N type collector layer and said P type base layer.

Claim 4

A method of manufacturing a semiconductor device which comprises the steps of: providing an N type collector layer in an N type silicon semiconductor wafer having a substantially flat surface; coating said N type collector layer with a first oxide film layer; forming a first opening in said first oxide film layer such that a portion of the surface of said N type collector layer is exposed; depositing a layer doped with an N type impurity having a high energy of combination with vacancies on said N type collector layer exposed by said first opening; diffusing said N type impurity from said N type impurity doped layer into said N type collector layer; removing said N type impurity doped layer from said N type collector layer; depositing a boron doped layer on said N type collector layer exposed by said first opening; diffusing boron from said boron doped layer into said N type collector layer such that a P type base layer in contact with said N type collector layer having a PN junction extending to said surface is formed; removing said boron doped layer from said N type collector; covering said N type collector layer and said P type base layer with a second oxide film layer; forming a second opening in said second oxide film layer, said second opening being smaller than said first opening in said first oxide film layer; and diffusing phosphorus and arsenic which are N type impurities through said second opening in said second oxide layer into said P type base layer such that an N type emitter layer is formed which is in contact with said P type base layer having a PN junction extending to said surface and which constitutes a transistor together with said N type collector layer and said P type base layer.