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US5981327A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for forming wells of semiconductor device

Assignee: SK Hynix Inc
•
Filing: 1998-03-17
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Granted: 1999-11-09
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Expires: 2018-03-17
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Abstract

Abstract A method for forming wells of a semiconductor device, comprising the steps of forming a plurality of field insulating layers on a field region of a semiconductor substrate; forming first impurity regions of a first conductive type at a first depth beneath a surface of the semiconductor substrate; forming first impurity regions of a second conductive type beneath the surface of the semiconductor substrate at a second depth between the field insulating layers; selectively forming second impurity regions of the second conductive type in the first impurity regions of the first conductive type between adjacent field insulating layers; forming second impurity regions of the first conductive type in the first impurity regions of the second conductive type at both sides of the second impurity regions of the second conductive type; and diffusing the first and second impurity regions of the first conductive type and the first and second impurity regions of the second conductive type by a drive-in process to form a first conductive type shield region, a first conductive type well, and first and second wells of a second conductive type.

Inventors

  • 👤 Jin-Ho Kim

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 16:12
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/031; H10W15/00; H10P; H10P30/00; H10P30/20; H10P30/22; H10W10/30; H10W15/01

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 182 words
A method for forming wells of a semiconductor device, comprising the steps of: forming a plurality of field insulating layers on a field region of a semiconductor substrate; forming first impurity regions of a first conductive type at a first depth beneath a surface of the semiconductor substrate; forming first impurity regions of a second conductive type beneath the surface of the semiconductor substrate at a second depth between the field insulating layers; selectively forming second impurity regions of the second conductive type in the first impurity regions of the first conductive type between adjacent field insulating layers; forming second impurity regions of the first conductive type in the first impurity regions of the second conductive type at both sides of the second impurity regions of the second conductive type; and diffusing the first and second impurity regions of the first conductive type and the first and second impurity regions of the second conductive type by a drive-in process to form a first conductive type shield region, a first conductive type well, and first and second wells of a second conductive type.
Claim 2
Independent Claim 182 words
A method for forming wells of a semiconductor device, comprising the steps of: forming a plurality of field insulating layers on a field region of a semiconductor substrate; forming first impurity regions of a first conductive type at a first depth beneath a surface of the semiconductor substrate; forming first impurity regions of a second conductive type beneath the surface of the semiconductor substrate at a second depth between the field insulating layers; selectively forming second impurity regions of the second conductive type in the first impurity regions of the first conductive type between adjacent field insulating layers; forming second impurity regions of the first conductive type in the first impurity regions of the second conductive type at both sides of the second impurity regions of the second conductive type; and diffusing the first and second impurity regions of the first conductive type and the first and second impurity regions of the second conductive type by a drive-in process to form a first conductive type shield region, a first conductive type well, and first and second wells of a second conductive type.
Claim 3
Dependent Claim 37 words
The method as claimed in claim 1, wherein the step of forming first impurity regions of the first conductive type includes implanting phosphorus ions having a first concentration with a first high energy without using a mask.
Claim 4
Dependent Claim 16 words
The method as claimed in claim 2, wherein the first high energy is approximately 500 KeV.
Claim 5
Dependent Claim 41 words
The method as claimed in claim 2, wherein the step of forming second impurity regions of the second conductive type includes implanting ions having a second concentration with a second high energy, the second concentration being higher than the first concentration.
Claim 6
Dependent Claim 31 words
The method as claimed in claim 4, wherein the ions implanted in forming the second impurity regions of the second conductive type include one of B ions and BF 2 ions.
Claim 7
Dependent Claim 20 words
The method as claimed in claim 4, wherein a photoresist pattern is used as a mask when implanting the ions.
Claim 8
Dependent Claim 40 words
The method as claimed in claim 1, wherein the step of forming first impurity regions of the second conductive type includes implanting B ions or BF 2 ions having a third concentration with a low energy without using a mask.
Claim 9
Dependent Claim 41 words
The method as claimed in claim 7, wherein the step of forming second impurity regions of the first conductive type includes implanting phosphorus ions having a fourth concentration with a low energy, the fourth concentration being higher than the third concentration.
Claim 10
Dependent Claim 25 words
The method as claimed in claim 8, wherein a photoresist pattern is used as a mask when implanting the phosphorous ions having the fourth concentration.
Claim 11
Dependent Claim 17 words
The method as claimed in claim 1, wherein the first depth is deeper than the second depth.
Claim 12
Dependent Claim 34 words
The method as claimed in claim 1, further comprising the step of forming a buffer oxide layer on the semiconductor substrate before the step of forming first impurity regions of a first conductive type.
Claim 13
Dependent Claim 22 words
The method as claimed in claim 1, wherein the second depth is level with bottoms of the plurality of field insulating layers.

References Cited (Backward Citations)

US5286666A Cited
US5536665A Cited
US5293060A Cited
US5693505A Cited
US5880014A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-11-08 2003-05-10 2003-11-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-11-08 2007-05-10 2007-11-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-11-08 2011-05-10 2011-11-09 $7700.00 Window Closed / Lapsed

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