Patent US4698128A successfully refreshed from Google Patents.
US4698128A
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Sloped contact etch process
Assignee: NXP USA Inc
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Filing: 1986-11-17
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Granted: 1987-10-06
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Expires: 2006-11-17
Abstract
Abstract A process described provides a sloped contact etch. The process has the steps of: etching a substrate then removing the polymer that is produced during the substrate etch. These two steps are alternated until a desired depth is reached. Next, the resist is etched followed by an etch of the substrate. This is then repeated until the required depth is reached. By varying the duration and repetition of the etches, the slope of the etch can be regulated.
Inventors
- 👤 Robert K. Berglund
- 👤 Karl E. Mautz
- 👤 Roger Tyldesley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:16
CPC Classifications
H; H10; H10P; H10P50/00; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081; H10W20/082; H10P50/20; H10P50/24; H10P50/242; H10P50/28; H10P50/282; H10P50/283; H10P50/69; H10P50/691; H10P50/693; H10P50/694; Y; Y10; Y10S; Y10S438/00; Y10S438/963; Y10S438/978
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
77 words
A process is claimed for providing a sloped contact etch comprising the steps of: (a) etching a substrate a first time in an area defined by a resist layer; (b) removing a polymer produced on said substrate during said step of etching said substrate a first time; (c) etching said resist layer thereby increasing the area of said substrate defined by said resist layer; and (d) etching said substrate in the area defined by said resist layer.
Claim 2
Dependent Claim
45 words
The process of claim 1 further comprising, following step (b), the steps of: etching said substrate a second time in said area defined by said resist layer; and removing a polymer produced on said substrate during said step of etching said substrate a second time.
Claim 3
Dependent Claim
27 words
The process of claim 1 further comprising, following step (d), the step of repeating steps (c) and (d) until a desired depth in said substrate is reached.
Claim 4
Dependent Claim
23 words
The process of claim 1 wherein said etching in steps (a) and (d) utilizes an etchant comprising CHF 3 and O 2 .
Claim 5
Dependent Claim
18 words
The process of claim 1 wherein said etching in step (b) utilizes an etchant comprising Argon and Oxygen.
Claim 6
Dependent Claim
16 words
The process of claim 1 wherein said etching is performed in a reactive ion etch reactor.
Claim 7
Dependent Claim
34 words
The process of claim 1 wherein a power level is ramped from a first level during step (a) down to a second level and ramped back up to a third level during step (c).
Claim 8
Dependent Claim
125 words
A process is claimed for providing a sloped contact etch comprising the steps of: (a) etching a substrate a first time in an area defined by a resist layer; (b) removing a polymer produced on said substrate during said step of etching said substrate a first time; (c) etching said substrate a second time in said area defined by said resist layer; (d) removing a polymer produced on said substrate during said step of etching said substrate a second time; (e) etching said substrate a third time in said area defined by said resist layer; (f) etching said resist layer thereby increasing the area of said substrate defined by said resist layer; and (g) etching said substrate in the area defined by said resist layer.
Claim 9
Dependent Claim
21 words
The process of claim 8 wherein the etching of steps (a), (c) and (e) has a duration of approximately 6.7 minutes.
Claim 10
Dependent Claim
20 words
The process of claim 8 wherein the etching of steps (b) and (d) has a duration of approximately 0.8 minutes.
Claim 11
Dependent Claim
18 words
The process of claim 8 wherein the etching of step (f) has a duration of approximately 2.1 minutes.
Claim 12
Dependent Claim
18 words
The process of claim 8 wherein the etching of step (g) has a duration of approximately 2.5 minutes.
Claim 13
Dependent Claim
24 words
The process of claim 8 further comprising, following step (g), the step of repeating steps (f) and (g) until a desired depth is reached.
Claim 14
Dependent Claim
25 words
The process of claim 8 wherein said etching in steps (a), (c), (e) and (g) utilizes an etchant comprising CHF 3 and O 2 .
Claim 15
Dependent Claim
21 words
The process of claim 8 wherein said etching in steps (b), (d) and (f) utilizes an etchant comprising Argon and Oxygen.
Claim 16
Dependent Claim
16 words
The process of claim 8 wherein said etching is performed in a reactive ion etch reactor.
Claim 17
Dependent Claim
44 words
The process of claim 8 wherein a power level is ramped from a first power level, utilized in steps (a), (c) (e) and (g), down to a second level and ramped back up to a third level, utilized in steps (b), (d) and (f).
Claim 18
Dependent Claim
140 words
A process is claimed for providing a sloped contact etch comprising the steps of: (a) etching a substrate a first time in an area defined by a resist layer; (b) removing a polymer produced on said substrate during said step of etching said substrate a first time; (c) etching said substrate a second time in said area defined by said resist layer; (d) removing a polymer produced on said substrate during said step of etching said substrate a second time; (e) etching said substrate a third time in said area defined by said resist layer; (f) etching said resist layer thereby increasing the area of said substrate defined by said resist layer; (g) etching said substrate in the area defined by said resist layer; and (h) repeating steps (f) and (g) until a via of a predetermined depth is reached.
Claim 19
Dependent Claim
33 words
The process of claim 18 wherein the etching of steps (a), (c) and (e) has a duration of approximately 6.7 minutes and utilizes an etchant comprised of CHF 3 and O 2 .
Claim 20
Dependent Claim
29 words
The process of claim 18 wherein the etching of steps (b) and (d) has a duration of approximately 0.8 minutes and utilizes an etchant comprised of Argon and Oxygen.
Claim 21
Dependent Claim
30 words
The process of claim 18 wherein the etching of step (f) has a duration of approximately 2.1 minutes and utilizes an etchant comprised of CHF 3 and O 2 .
Claim 22
Dependent Claim
27 words
The process of claim 18 wherein the etching of step (g) has a duration of approximately 2.5 minutes and utilizes an etchant comprised of Argon and Oxygen.
References Cited (Backward Citations)
US4361599A
Cited
US4522681A
Cited
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