Abstract A semiconductor device in which a bipolar transistor is provided, such as a BiCMOS, and a production process thereof. The device has collector region of a first conductivity type; an intrinsic base region of a second conductivity type provided on the collector region; a graft base provided on the periphery of this intrinsic base region; and an emitter region of the first conductivity type provided by self-alignment with respect to the intrinsic base. A base electrode is provided in the upper portion where the graft base is scheduled to be formed. A trench is provided by self-alignment along the end portion on the outer circumference side of this base electrode. The graft base is provided in contact with the inner circumference of this trench.
A production process of a bipolar type semiconductor device comprising: a step of forming a collector region of a first conductivity type on the surface of a semiconductor substrate; a step of forming on the surface of said semiconductor substrate on which the collector region is formed a stopper layer covering a part corresponding to an intrinsic base region and having a first opening portion exposing a region including a graft base formed on the outer circumference of the intrinsic base region; a step of forming a conductive layer having an impurity substance of a second conductive type on the surface of said stopper layer in which the first opening portion is formed; a step of forming a base electrode by etching said conductive layer with a pattern that partially overlaps said first opening portion and forming a second opening portion exposing the surface of the stopper layer corresponding to the intrinsic base region at the end portion on the inner circumference side of the base electrode; a step of forming a trench on the surface of the semiconductor substrate partially exposed by said first opening portion along the end portion on the outer circumference side of said base electrode; a step of forming the intrinsic base region of a second conductivity type by self-alignment on the surface of the semiconductor substrate through the second opening portion provided along the end portion on the inner circumference side of said base electrode; a step of forming an insulation side wall with respect to said second opening portion and forming an emitter region of the first conductivity type by self-alignment on the surface of said intrinsic base region; and a step of diffusing said impurity substance of the second conductivity type from said base electrode into a region defined by said trench to form a graft base on the substrate.
Claim 2
Dependent Claim
308 words
A production process of a bipolar type semiconductor device comprising: a step of forming a collector region of a first conductivity type on the surface of a semiconductor substrate; a step of forming on the surface of said semiconductor substrate on which the collector region is formed a stopper layer covering a part corresponding to an intrinsic base region and having a first opening portion exposing a region including a graft base formed on the outer circumference of the intrinsic base region; a step of forming a conductive layer having an impurity substance of a second conductive type on the surface of said stopper layer in which the first opening portion is formed; a step of forming a base electrode by etching said conductive layer with a pattern that partially overlaps said first opening portion and forming a second opening portion exposing the surface of the stopper layer corresponding to the intrinsic base region at the end portion on the inner circumference side of the base electrode; a step of forming a trench on the surface of the semiconductor substrate partially exposed by said first opening portion along the end portion on the outer circumference side of said base electrode; a step of forming the intrinsic base region of a second conductivity type by self-alignment on the surface of the semiconductor substrate through the second opening portion provided along the end portion on the inner circumference side of said base electrode; a step of forming an insulation side wall with respect to said second opening portion and forming an emitter region of the first conductivity type by self-alignment on the surface of said intrinsic base region; and a step of diffusing said impurity substance of the second conductivity type from said base electrode into a region defined by said trench to form a graft base on the substrate.
Claim 3
Dependent Claim
37 words
The production process according to claim 1, wherein a step of forming said second opening portion and a step of forming said trench are simultaneously carried out by the etching at the patterning of the base electrode.
Claim 4
Dependent Claim
33 words
The production process according to claim 1, wherein the conductive layer acting as said base electrode is simultaneously formed by a polycide layer for forming a gate electrode of a MOS transistor portion.
Claim 5
Dependent Claim
32 words
The production process according to claim 1, wherein said trench is simultaneously formed at the time of etching when a gate electrode of a MOS transistor portion is subjected to the patterning.
Claim 6
Dependent Claim
238 words
A production process of a bipolar type semiconductor device comprising: a step of forming a collector region of a first conductivity type on the surface of a semiconductor substrate; a step of forming a conductive layer having an impurity substance of a second conductive type on a surface of said semiconductor substrate on which said collector region is provided; a step of forming an opening portion in said conductive layer with a pattern corresponding to an intrinsic base region; a step of forming a base electrode by etching said conductive layer by a resist film masked with a pattern filling said opening portion and covering a graft base and forming a trench on the surface of said semiconductor substrate along the end portion on the outer circumference side of said resist film; a step of forming the intrinsic base region of a second conductivity type in the self-alignment manner on the surface of the semiconductor substrate through said opening portion provided along the end portion on the inner circumference side of said base electrode; a step of forming an insulation side wall with respect to said second opening portion and forming an emitter region of the first conductivity type by self-alignment on the surface of said intrinsic base region; and a step of diffusing said impurity substance of a second conductivity type from said base electrode into a region defined by said trench to form the graft base.
Claim 7
Dependent Claim
238 words
A production process of a bipolar type semiconductor device comprising: a step of forming a collector region of a first conductivity type on the surface of a semiconductor substrate; a step of forming a conductive layer having an impurity substance of a second conductive type on a surface of said semiconductor substrate on which said collector region is provided; a step of forming an opening portion in said conductive layer with a pattern corresponding to an intrinsic base region; a step of forming a base electrode by etching said conductive layer by a resist film masked with a pattern filling said opening portion and covering a graft base and forming a trench on the surface of said semiconductor substrate along the end portion on the outer circumference side of said resist film; a step of forming the intrinsic base region of a second conductivity type in the self-alignment manner on the surface of the semiconductor substrate through said opening portion provided along the end portion on the inner circumference side of said base electrode; a step of forming an insulation side wall with respect to said second opening portion and forming an emitter region of the first conductivity type by self-alignment on the surface of said intrinsic base region; and a step of diffusing said impurity substance of a second conductivity type from said base electrode into a region defined by said trench to form the graft base.