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US5075242A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of manufacturing CMOS semiconductor device having decreased diffusion layer capacitance

Assignee: Toshiba Corp
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Filing: 1989-12-14
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Granted: 1991-12-24
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Expires: 2009-12-14
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Abstract

Abstract A method of manufacturing a CMOS semiconductor device includes the step of preparing a substrate having a first region of a second conductivity type serving as prospective source and drain formation regions of a transistor of a first conductivity type, and a second region of the first conductivity type serving as a prospective channel formation region of a transistor of the second conductivity type. The method of manufacturing the device further includes the steps of simultaneously doping an impurity of the first conductivity type having a first concentration in a first depth of each of the first and second regions, and doping an impurity of the first conductivity type having a concentration higher than the first concentration in a second depth smaller than the first depth of the first region.

Inventors

  • 👤 Moriya Nakahara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 02:02
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/0167; H10P; H10P30/00; H10P30/20; H10P30/21; H10D84/017; H10D84/02; H10D84/03; H10D84/038; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10P30/202; H10P30/204

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 119 words
A method of manufacturing a CMOS semiconductor device, comprising the steps of: preparing a substrate having a first region of a second conductivity type serving as prospective source and drain formation regions of a transistor of a first conductivity type, and a second region of the first conductivity type serving as a prospective channel formation region of a transistor of the second conductivity type; simultaneously doping an impurity of the first conductivity type having a first concentration in a first depth of each of said first and second regions; and doping an impurity of the first conductivity type having a concentration higher than the first concentration in a second depth smaller than the first depth of said first region.
Claim 2
Independent Claim 119 words
A method of manufacturing a CMOS semiconductor device, comprising the steps of: preparing a substrate having a first region of a second conductivity type serving as prospective source and drain formation regions of a transistor of a first conductivity type, and a second region of the first conductivity type serving as a prospective channel formation region of a transistor of the second conductivity type; simultaneously doping an impurity of the first conductivity type having a first concentration in a first depth of each of said first and second regions; and doping an impurity of the first conductivity type having a concentration higher than the first concentration in a second depth smaller than the first depth of said first region.
Claim 3
Dependent Claim 20 words
A method according to claim 1, wherein the first depth is about 0.25 μm from a portion near a surface.
Claim 4
Dependent Claim 20 words
A method according to claim 1, wherein the second depth is about 0.1 μm from a portion near the surface.
Claim 5
Dependent Claim 48 words
A method according to claim 1, wherein the step of doping the impurity of the first conductivity type having the first concentration includes the step of ion-implanting boron in the second depth at a accelerated energy of 40 keV and a dose of 3×10 12 ions/cm 2 .
Claim 6
Dependent Claim 48 words
A method according to claim 1, wherein the step of doping the impurity of the first conductivity type having the higher concentration includes the step of ion-implanting boron in the first depth at an accelerated energy of 80 keV and a dose of 2×10 12 ions/cm 2 .
Claim 7
Dependent Claim 48 words
A method according to claim 1, wherein the step of doping the impurity of the first conductivity type having the higher concentration includes the step of ion-implanting phosphorus in the first depth at an accelerated energy of 240 keV and a dose of 6×10 12 ions/cm 2 .
Claim 8
Independent Claim 220 words
A method of manufacturing a CMOS semiconductor device, comprising the steps of: preparing a substrate having a first region of a second conductivity type serving as prospective source and drain formation regions of a transistor of a first conductivity type, a second region of the second conductivity type serving as a prospective channel formation region of the transistor of the first conductivity type, a third region of the first conductivity type serving as prospective source and drain formation regions of a transistor of the second conductivity type, and a fourth region of the first conductivity type serving as a prospective channel formation region of the transistor of the second conductivity type; simultaneously doping an impurity of the first conductivity type having a first concentration in a first depth of each of said first and fourth regions; doping an impurity of the first conductivity type having a concentration higher than the first concentration in a second depth smaller than the first depth of said first region; simultaneously doping an impurity of the second conductivity type having a second concentration in a third depth of each of said second and third regions; and doping an impurity of the second conductivity type having a concentration higher than the second concentration in a fourth depth smaller than the third depth of said third region.
Claim 9
Independent Claim 220 words
A method of manufacturing a CMOS semiconductor device, comprising the steps of: preparing a substrate having a first region of a second conductivity type serving as prospective source and drain formation regions of a transistor of a first conductivity type, a second region of the second conductivity type serving as a prospective channel formation region of the transistor of the first conductivity type, a third region of the first conductivity type serving as prospective source and drain formation regions of a transistor of the second conductivity type, and a fourth region of the first conductivity type serving as a prospective channel formation region of the transistor of the second conductivity type; simultaneously doping an impurity of the first conductivity type having a first concentration in a first depth of each of said first and fourth regions; doping an impurity of the first conductivity type having a concentration higher than the first concentration in a second depth smaller than the first depth of said first region; simultaneously doping an impurity of the second conductivity type having a second concentration in a third depth of each of said second and third regions; and doping an impurity of the second conductivity type having a concentration higher than the second concentration in a fourth depth smaller than the third depth of said third region.
Claim 10
Dependent Claim 20 words
A method according to claim 7, wherein the first depth is about 0.25 μm from a portion near a surface.
Claim 11
Dependent Claim 20 words
A method according to claim 7, wherein the second depth is about 0.1 μm from a portion near the surface.
Claim 12
Dependent Claim 44 words
A method according to claim 7, wherein the step of doping the impurity of the first conductivity type having the first concentration includes the step of ion-implanting boron at an accelerated energy of 40 keV and a dose of 3×10 12 ions/cm 2 .
Claim 13
Dependent Claim 44 words
A method according to claim 7, wherein the step of doping the impurity of the first conductivity type having the higher concentration includes the step of ion-implanting boron at an accelerated energy of 80 keV and a dose of 2×10 12 ions/cm 2 .
Claim 14
Dependent Claim 43 words
A method according to claim 7, wherein the step of doping the impurity of the first conductivity type having the higher concentration includes the step of ion-implanting phosphorus at an accelerated voltage of 240 keV a dose of 6×10 12 ions/cm 2 .
Claim 15
Independent Claim 154 words
A method of manufacturing a CMOS semiconductor device, comprising the steps of: preparing a substrate having a first region of a second conductivity type serving as prospective source and drain formation regions of a transistor of a first conductivity type, a second region of the second conductivity type serving as a prospective channel formation region of the transistor of the first conductivity type, and a third region of the first conductivity type serving as a prospective channel formation region of the transistor of the second conductivity type; simultaneously doping an impurity of the first conductivity type having a first concentration in a first depth of each of said first region spaced apart from said second region by a predetermined distance and said third region; and doping an impurity of the first conductivity type having a concentration higher than the first concentration in a second depth smaller than the first depth of said first region.
Claim 16
Independent Claim 154 words
A method of manufacturing a CMOS semiconductor device, comprising the steps of: preparing a substrate having a first region of a second conductivity type serving as prospective source and drain formation regions of a transistor of a first conductivity type, a second region of the second conductivity type serving as a prospective channel formation region of the transistor of the first conductivity type, and a third region of the first conductivity type serving as a prospective channel formation region of the transistor of the second conductivity type; simultaneously doping an impurity of the first conductivity type having a first concentration in a first depth of each of said first region spaced apart from said second region by a predetermined distance and said third region; and doping an impurity of the first conductivity type having a concentration higher than the first concentration in a second depth smaller than the first depth of said first region.
Claim 17
Dependent Claim 20 words
A method according to claim 13, wherein the predetermined distance falls within the range of about 0.5 to 1.5 μm.
Claim 18
Dependent Claim 24 words
A method according to claim 13, wherein the predetermined distance is substantially equal to the depths of said prospective source and drain formation regions.

References Cited (Backward Citations)

US4530150A Cited
US4553315A Cited
US4697148A Cited
US5021356A Cited

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