Method of controlling base contact regions by forming a blocking layer contiguous to a doped poly-si emitter source

Claim 1

A method of manufacturing a semiconductor device comprising the steps in the following order of: (a) forming a film doped with an emitter impurity on a predetermined surface area of a semiconductor layer which surface area constitutes an island region isolated by an insulating layer; (b) forming an ion implantation blocking layer covering said doped film and the exposed surface of said semiconductor layer; (c) anisotropically etching said blocking layer until the surface of said doped film is substantially exposed, by irradiating said blocking layer with a dry etchant in a direction substantially normal to said semiconductor layer, thereby allowing a portion of said blocking layer to remain surrounding said doped film and substantially forming a base contact hole defined between the exposed side surfaces of said remaining blocking layer and said insulating layer; (d) conducting ion implantation with respect to said semiconductor layer, with said remaining blocking layer and said doped film used as a mask, to form at least a base contact region of a high impurity concentration in a portion of said semiconductor layer corresponding to said base contact hole; and (e) forming an emitter region in said semiconductor layer by diffusing the impurity from said doped film into said semiconductor layer by a thermal treatment.

Claim 2

A method of manufacturing a semiconductor device comprising the steps in the following order of: (a) forming a film doped with an emitter impurity on a predetermined surface area of a semiconductor layer which surface area constitutes an island region isolated by an insulating layer; (b) forming an ion implantation blocking layer covering said doped film and the exposed surface of said semiconductor layer; (c) anisotropically etching said blocking layer until the surface of said doped film is substantially exposed, by irradiating said blocking layer with a dry etchant in a direction substantially normal to said semiconductor layer, thereby allowing a portion of said blocking layer to remain surrounding said doped film and substantially forming a base contact hole defined between the exposed side surfaces of said remaining blocking layer and said insulating layer; (d) conducting ion implantation with respect to said semiconductor layer, with said remaining blocking layer and said doped film used as a mask, to form at least a base contact region of a high impurity concentration in a portion of said semiconductor layer corresponding to said base contact hole; and (e) forming an emitter region in said semiconductor layer by diffusing the impurity from said doped film into said semiconductor layer by a thermal treatment.

Claim 15

A method of manufacturing a semiconductor device comprising the steps of the following order of: (a) forming a film doped with an emitter impurity on a predetermined surface area of a semiconductor layer which surface area constitutes an island region isolated by an insulating layer; (b) forming an ion implantation blocking layer covering said dope film and the exposed surface of said semiconductor layer; (c) anisotropically etching said portion of said blocking layer by irradiating said blocking layer with a dry etchant in a direction substantially normal to said semiconductor layer, thereby allowing a portion of said blocking layer to remain surrounding said doped film and substantially forming a base contact hole defined between the exposed side surfaces of said remaining blocking layer and said insulating layer; (d) conducing ion implantation with respect to said semiconductor layer, with said remaining blocking layer and said doped film used as a mask, to form at least a base contact region of a high impurity concentration in a portion of said semiconductor layer corresponding to said base contact hole; (e) anisotropically etching the remainder of said blocking layer in the manner of step (c) until the surface of said doped film is substantially exposed; and (f) forming an emitter region in said semiconductor layer by diffusing the impurity from said doped film into said semiconductor layer by a thermal treatment.

Claim 16

A method of manufacturing a semiconductor device comprising the steps of the following order of: (a) forming a film doped with an emitter impurity on a predetermined surface area of a semiconductor layer which surface area constitutes an island region isolated by an insulating layer; (b) forming an ion implantation blocking layer covering said dope film and the exposed surface of said semiconductor layer; (c) anisotropically etching said portion of said blocking layer by irradiating said blocking layer with a dry etchant in a direction substantially normal to said semiconductor layer, thereby allowing a portion of said blocking layer to remain surrounding said doped film and substantially forming a base contact hole defined between the exposed side surfaces of said remaining blocking layer and said insulating layer; (d) conducing ion implantation with respect to said semiconductor layer, with said remaining blocking layer and said doped film used as a mask, to form at least a base contact region of a high impurity concentration in a portion of said semiconductor layer corresponding to said base contact hole; (e) anisotropically etching the remainder of said blocking layer in the manner of step (c) until the surface of said doped film is substantially exposed; and (f) forming an emitter region in said semiconductor layer by diffusing the impurity from said doped film into said semiconductor layer by a thermal treatment.