Patent US5378648A successfully refreshed from Google Patents.
US5378648A
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Situ stringer removal during polysilicon capacitor cell plate delineation
Assignee: Micron Technology Inc
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Filing: 1993-12-02
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Granted: 1995-01-03
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Expires: 2013-12-02
Abstract
Abstract Capacitors such as storage cells for Dynamic Random Access Memories are formed in a process for etching a polycrystalline silicon layer to form a storage cell during the manufacture of a semiconductor device. The etch results in a cell having reduced undercutting of the poly cell, and eliminates the formation of poly stringers. The inventive etch comprises the use of NF 3 and/or SF 6 during a magnetically enhanced low pressure reactive ion etch using a carbon-free etch gas of Cl 2 .
Inventors
- 👤 Audrey P. Lin
- 👤 Guy T. Blalock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:48
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268; Y; Y10; Y10S; Y10S438/00; Y10S438/963
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
93 words
A process for removing polycrystalline silicon from the surface of a substrate during the formation of a semiconductor device with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas comprising chlorine; b) adding a compound selected from the group consisting of SF 6 and NF 3 to said etch gas; c) applying a pressure within said chamber of less than 50 millitorr; d) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
Claim 2
Dependent Claim
93 words
A process for removing polycrystalline silicon from the surface of a substrate during the formation of a semiconductor device with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas comprising chlorine; b) adding a compound selected from the group consisting of SF 6 and NF 3 to said etch gas; c) applying a pressure within said chamber of less than 50 millitorr; d) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
Claim 3
Dependent Claim
17 words
The process of claim 1 wherein said pressure applied within said chamber is greater than 10 millitorr.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein said pressure applied within said chamber is about 20 millitorr.
Claim 5
Dependent Claim
28 words
The process of claim 1 wherein said compound is added to said etch gas to a concentration of between 2 standard cubic centimeters and 20 standard cubic centimeters.
Claim 6
Dependent Claim
25 words
The process of claim 1 wherein said etch gas comprises chlorine in a concentration of between 20 standard cubic centimeters and 70 standard cubic centimeters.
Claim 7
Dependent Claim
22 words
The process of claim 1 wherein said magnetic force applied to said etch gas is between about 120 gauss and 130 gauss.
Claim 8
Dependent Claim
21 words
The process of claim 1 wherein said compound added to said etch gas comprises both SF 6 and NF 3 .
Claim 9
Dependent Claim
18 words
The process of claim 1 wherein said polycrystalline silicon layer is formed over a layer of tetraethyl orthosilicate.
Claim 10
Dependent Claim
102 words
A process for forming a memory storage device having a stacked capacitor design comprising the removal of polycrystalline silicon from the surface of a substrate with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas comprising chlorine within said chamber; b) adding a compound selected from the group consisting of SF 6 and NF 3 to said etch gas; c) applying a pressure within said chamber of less than 50 millitorr; d) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
Claim 11
Dependent Claim
102 words
A process for forming a memory storage device having a stacked capacitor design comprising the removal of polycrystalline silicon from the surface of a substrate with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas comprising chlorine within said chamber; b) adding a compound selected from the group consisting of SF 6 and NF 3 to said etch gas; c) applying a pressure within said chamber of less than 50 millitorr; d) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
Claim 12
Dependent Claim
16 words
The process of claim wherein said pressure applied within said chamber is greater than 10 millitorr.
Claim 13
Dependent Claim
16 words
The process of claim 9 wherein said pressure applied within said chamber is about 20 millitorr.
Claim 14
Dependent Claim
28 words
The process of claim 9 wherein said compound is added to said etch gas to a concentration of between 2 standard cubic centimeters and 20 standard cubic centimeters.
Claim 15
Dependent Claim
25 words
The process of claim 9 wherein said etch gas comprises chlorine in a concentration of between 20 standard cubic centimeters and 70 standard cubic centimeters.
Claim 16
Dependent Claim
22 words
The process of claim 9 wherein said magnetic force applied to said etch gas is between about 120 gauss and 130 gauss.
Claim 17
Dependent Claim
21 words
The process of claim 9 wherein said compound added to said etch gas comprises both SF 6 and NF 3 .
Claim 18
Dependent Claim
18 words
The process of claim 9 wherein said polycrystalline silicon layer is formed over a layer of tetraethyl orthosilicate.
Claim 19
Dependent Claim
110 words
A process for etching polycrystalline silicon with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas comprising chlorine in a concentration of between 20 standard cubic centimeters and 70 standard cubic centimeters; b) adding a compound selected from the group consisting of SF 6 and NF 3 to said etch gas in a concentration of between 2 standard cubic centimeters and 20 standard cubic centimeters; c) applying a pressure within said chamber of between 10 millitorr and 50 millitorr; d) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
Claim 20
Dependent Claim
110 words
A process for etching polycrystalline silicon with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas comprising chlorine in a concentration of between 20 standard cubic centimeters and 70 standard cubic centimeters; b) adding a compound selected from the group consisting of SF 6 and NF 3 to said etch gas in a concentration of between 2 standard cubic centimeters and 20 standard cubic centimeters; c) applying a pressure within said chamber of between 10 millitorr and 50 millitorr; d) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
Claim 21
Dependent Claim
16 words
The process of claim 17 wherein said pressure applied within said chamber is about 20 millitorr.
Claim 22
Dependent Claim
22 words
The process of claim 17 wherein said magnetic force applied to said etch gas is between about 120 gauss and 130 gauss.
Claim 23
Dependent Claim
18 words
The process of claim 17 wherein said polycrystalline silicon layer is formed over a layer of tetraethyl orthosilicate.
Claim 24
Dependent Claim
91 words
A process for removing polycrystalline silicon from the surface of a substrate during the formation of a semiconductor device with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas consisting essentially of chlorine and a compound selected from the group consisting of SF 6 and NF 3 ; b) applying a pressure within said chamber of less than 50 millitorr; c) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
Claim 25
Dependent Claim
91 words
A process for removing polycrystalline silicon from the surface of a substrate during the formation of a semiconductor device with an etch in a chamber, said etch comprising the following steps: a) providing a carbon-free etch gas consisting essentially of chlorine and a compound selected from the group consisting of SF 6 and NF 3 ; b) applying a pressure within said chamber of less than 50 millitorr; c) applying a magnetic force of between 75 gauss and 150 gauss to said etch gas in a direction parallel with said surface.
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