EP0649169A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Etching MoSi2 using SF6, HBr and 02
Assignee: Applied Materials Inc
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Filing: 1994-10-13
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Granted: —
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Expires: 2014-10-13
Abstract
Abstract A process for selectively etching a substrate (20) having a molybdenum disilicide layer (25) with a resist material (26) on portions of the molybdenum silicide layer (25) is described. The substrate (20) is placed into an etch zone and a process gas comprising SF 6 and HBr is introduced into the etch zone. Preferably, the volumetric flow ratio of SF 6 :HBr is from about 1:10 to about 1:1, and more preferably, an oxygen containing gas such as 0 2 is added to the process gas. A plasma is generated in the etch zone to form an etch gas from the process gas that anisotropically etches the MoSi X layer (25) with good selectivity and reduced profile microloading.
Inventors
- 👤 Ernest L. Cheung
- 👤 Patty Hui-Ing Tsai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 11:09
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
108 words
A method for selectively etching a substrate (20) having a molybdenum silicide layer (25) with a resist material (26) on the portions of the molybdenum silicide layer (25), the method comprising the steps of: (a) placing a substrate (20) into an etch zone (54); (b) introducing a process gas comprising SF 6 and HBr into the etch zone (54), the volumetric flow ratio of SF 6 :HBr being from about 1:10 to about 1:1; and (c) generating a plasma in the etch zone (54) to form an etch gas from the process gas, wherein the etch gas selectively etches the molybdenum silicide layer (25) on the substrate (20).
Claim 2
Independent Claim
108 words
A method for selectively etching a substrate (20) having a molybdenum silicide layer (25) with a resist material (26) on the portions of the molybdenum silicide layer (25), the method comprising the steps of: (a) placing a substrate (20) into an etch zone (54); (b) introducing a process gas comprising SF 6 and HBr into the etch zone (54), the volumetric flow ratio of SF 6 :HBr being from about 1:10 to about 1:1; and (c) generating a plasma in the etch zone (54) to form an etch gas from the process gas, wherein the etch gas selectively etches the molybdenum silicide layer (25) on the substrate (20).
Claim 3
Dependent Claim
15 words
The method of claim 1, wherein the process gas further comprises an oxygen containing gas.
Claim 4
Dependent Claim
54 words
The method of claim 2, wherein the molybdenum silicide layer (25) is etched to form features that have sidewalls (30), and wherein the volumetric flow ratio of SF 6 :HBr:oxygen containing gas is selected so that the sidewalls (30) are smooth and form angles of at least about 85 ° with the substrate (20).
Claim 5
Dependent Claim
37 words
The method of claim 3, wherein the volumetric flow ratio of SF 6 :HBr:oxygen containing gas is selected so that the sidewalls (30) form angles from about 85 ° to about 90 ° with the substrate (20).
Claim 6
Dependent Claim
33 words
The method of claim 2, wherein the volumetric flow ratio of SF 6 :HBr:oxygen containing gas is selected so that the molybdenum silicide to resist etching selectivity ratio is greater than about 0.6.
Claim 7
Dependent Claim
32 words
The method of claim 2, wherein the volumetric flow ratio of SF 6 :HBr:oxygen containing gas is selected so that molybdenum silicide etch rate is greater than about 0.83 nm/s (500 A/minute).
Claim 8
Dependent Claim
21 words
The method of claim 1, wherein the volumetric flow ratio of SF 6 :HBr is from about 3:17 to about 7:13.
Claim 9
Dependent Claim
17 words
The method of claim 7, wherein the volumetric flow ratio of SF 6 :HBr is about 1:3.
Claim 10
Dependent Claim
33 words
The method of claim 2, wherein the oxygen containing gas is selected from the group consisting of 0 2 , 0 3 , CO, C0 2 , H 2 0 and mixtures thereof.
Claim 11
Dependent Claim
24 words
The method of claim 2, wherein the volumetric flow ratio of SF 6 to oxygen containing gas is from about 0.1:1 to about 100:1.
Claim 12
Dependent Claim
24 words
The method of claim 10, wherein the volumetric flow ratio of SF 6 to oxygen containing gas is from about 1:1 to about 10:1.
Claim 13
Dependent Claim
24 words
The method of claim 11, wherein the volumetric flow ratio of SF 6 to oxygen containing gas is from about 1:1 to about 3:1.
Claim 14
Dependent Claim
25 words
The method of claim 1, wherein the pressure in the etch zone is from about 6.65 to about 33.25 Pa (50 to about 250 mTorr).
Claim 15
Dependent Claim
25 words
The method of claim 13, wherein the pressure in the etch zone is from about 13.3 to about 21.28 Pa (100 to about 160 mTorr).
Claim 16
Independent Claim
41 words
The method of any of claims 1 to 14, wherein the step of introducing a process gas comprises introducing sufficient process gas so that the rate of etching the substrate (20) is greater than about 0.83 nm/s (500 A per minute).
Claim 17
Independent Claim
56 words
The method of any of claims 1 to 15, wherein the substrate (20) comprises a semiconductor wafer (22) selected from the group consisting of silicon and gallium arsenide wafers, the wafer having a plurality of layers (24a, 24b) thereon, the layers being selected from the group consisting of metal, oxide, nitride, silicide, and the mixtures thereof.
Claim 18
Independent Claim
170 words
A method for selectively etching a substrate, comprising the steps of: (a) placing a substrate (20) selected from the group consisting of silicon and gallium arsenide wafers into an etch zone (54), the substrate (20) having thereon (i) a plurality of layers (24a, 24b) selected from the group consisting of metal, oxide, nitride, silicide, and mixtures thereof, (ii) a molybdenum silicide layer (25), and (iii) a resist material (26) on portions of the molybdenum silicide layer (25); (b) introducing a process gas into the etch zone (54), the process gas comprising SF 6 , HBr, and 0 2 , wherein the volumetric flow ratio of SF6 :HBr is from about 1:10 to about 1:1, and the volumetric flow ratio of SFe:0 2 is from about 0.1:1 to 100:1; (c) generating a plasma in the etch zone (54) to generate from the process gas an etch gas that etches the substrate layers to create volatile etch byproduct compounds; and (d) removing the volatile etch byproduct compounds from the etch zone (54).
Claim 19
Independent Claim
170 words
A method for selectively etching a substrate, comprising the steps of: (a) placing a substrate (20) selected from the group consisting of silicon and gallium arsenide wafers into an etch zone (54), the substrate (20) having thereon (i) a plurality of layers (24a, 24b) selected from the group consisting of metal, oxide, nitride, silicide, and mixtures thereof, (ii) a molybdenum silicide layer (25), and (iii) a resist material (26) on portions of the molybdenum silicide layer (25); (b) introducing a process gas into the etch zone (54), the process gas comprising SF 6 , HBr, and 0 2 , wherein the volumetric flow ratio of SF6 :HBr is from about 1:10 to about 1:1, and the volumetric flow ratio of SFe:0 2 is from about 0.1:1 to 100:1; (c) generating a plasma in the etch zone (54) to generate from the process gas an etch gas that etches the substrate layers to create volatile etch byproduct compounds; and (d) removing the volatile etch byproduct compounds from the etch zone (54).
References Cited (Backward Citations)
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