Patent US5674784A successfully refreshed from Google Patents.
US5674784A
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Method for forming polish stop layer for CMP process
Assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
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Filing: 1996-10-02
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Granted: 1997-10-07
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Expires: 2016-10-02
Abstract
Abstract A method is disclosed for planarizing interlevel dielectric layers in semiconductor wafers extremely smoothly. The key aspect of the disclosure is a buried stop layer that is ion implanted into the interlevel layer. It is shown that the stop layer can be formed at precise depths from the surface of the oxide layer and in a mostly planar surface. When the oxide layer with the buried stop layer is chemical/mechanically polished in the conventional manner, polishing stops at the stop layer yielding also a planar surface. The planarity of the polished surface can be extremely refined by first forming an extremely refined stop layer. The latter is accomplished by first planarizing the surface of the oxide layer in a number of ways before implanting the stop layer. It is further shown that when nitrogen atoms are used as the species for implanting, the resulting stop layer acquires a hardness very favorable for being differentiated from the softer oxide layer. Such abrupt difference in hardness provides a very precise polishing endpoint. At the same time, overpolishing of the interlevel layer is avoided.
Inventors
- 👤 Syun-Ming Jang
- 👤 Chen-Hua Yu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:58
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/092; H10P; H10P14/00; H10P14/60; H10P95/00; H10P95/06; H10P95/062; Y; Y10; Y10S; Y10S438/00; Y10S438/97
Claims Analysis
Total Claims: 43
Claim 1
Independent Claim
56 words
A method of forming a polish stop layer for chemical/mechanical polishing (CMP) of semiconductor wafers comprising the steps of: providing a wiring layer comprising aluminum on said wafer; providing an oxide layer on said wiring layer; ion implanting atoms in said oxide layer to form a polish stop layer; and chemical/mechanical polishing (CMP) said oxide layer.
Claim 2
Independent Claim
56 words
A method of forming a polish stop layer for chemical/mechanical polishing (CMP) of semiconductor wafers comprising the steps of: providing a wiring layer comprising aluminum on said wafer; providing an oxide layer on said wiring layer; ion implanting atoms in said oxide layer to form a polish stop layer; and chemical/mechanical polishing (CMP) said oxide layer.
Claim 3
Dependent Claim
11 words
The method of claim 1, wherein said wiring layer is aluminum-copper.
Claim 4
Dependent Claim
12 words
The method of claim 1, wherein said oxide layer is silicon oxide.
Claim 5
Dependent Claim
16 words
The method of claim 1, wherein said ion implanting is accomplished by means of high-energy implanter.
Claim 6
Dependent Claim
10 words
The method of claim 1, wherein said atoms are nitrogen.
Claim 7
Dependent Claim
18 words
The method of claim 5, wherein energy of said nitrogen atoms is between about 350 to 450 keV.
Claim 8
Dependent Claim
23 words
The method of claim 5, wherein the dose of said nitrogen atoms is between about 2×10 14 to 5×10 4 ions/cm 2 .
Claim 9
Dependent Claim
19 words
The method of claim 5, wherein duration for implanting said nitrogen atoms is between about 50 to 70 seconds.
Claim 10
Dependent Claim
20 words
The method of claim 5, wherein implanting depth of said nitrogen atoms is between about 9000 to 11000 angstroms (Å).
Claim 11
Dependent Claim
21 words
The method of claim 1, wherein said polish stop layer has a hardness between about 8 to 9 in Mohs scale.
Claim 12
Dependent Claim
13 words
The method of claim 1, wherein said CMP is accomplished with a slurry.
Claim 13
Dependent Claim
13 words
The method of claim 11, wherein said slurry consists of SiO 2 particles.
Claim 14
Independent Claim
65 words
A method of forming a polish stop layer for chemical/mechanical polishing (CMP) of semiconductor wafers comprising the steps of: providing a wiring layer comprising aluminum on said wafer; providing an oxide layer on said wiring layer; depositing a planarizing glass layer on said wiring layer; ion implanting atoms in said oxide layer to form a polish stop layer; and chemical/mechanical polishing (CMP) said oxide layer.
Claim 15
Independent Claim
65 words
A method of forming a polish stop layer for chemical/mechanical polishing (CMP) of semiconductor wafers comprising the steps of: providing a wiring layer comprising aluminum on said wafer; providing an oxide layer on said wiring layer; depositing a planarizing glass layer on said wiring layer; ion implanting atoms in said oxide layer to form a polish stop layer; and chemical/mechanical polishing (CMP) said oxide layer.
Claim 16
Dependent Claim
11 words
The method of claim 13, wherein said wiring layer is aluminum-copper.
Claim 17
Dependent Claim
12 words
The method of claim 13, wherein said oxide layer is silicon oxide.
Claim 18
Dependent Claim
11 words
The method of claim 13, wherein said glass is spin-on-glass (SOG).
Claim 19
Dependent Claim
19 words
The method of claim 16 wherein said SOG is cured at a temperature between about 390° to 430° C.
Claim 20
Dependent Claim
16 words
The method of claim 13, wherein said ion implanting is accomplished by means of high-energy implanter.
Claim 21
Dependent Claim
10 words
The method of claim 13, wherein said atoms are nitrogen.
Claim 22
Dependent Claim
18 words
The method of claim 19, wherein energy of said nitrogen atoms is between about 350 to 450 keV.
Claim 23
Dependent Claim
23 words
The method of claim 19, wherein the dose of said nitrogen atoms is between about 2×10 4 to 5×10 4 ions/cm 2 .
Claim 24
Dependent Claim
19 words
The method of claim 19, wherein duration for implanting said nitrogen atoms is between about 50 to 70 seconds.
Claim 25
Dependent Claim
20 words
The method of claim 19, wherein implanting depth of said nitrogen atoms is between about 9,000 to 11,000 angstroms (Å).
Claim 26
Dependent Claim
21 words
The method of claim 13, wherein said polish stop layer has a hardness between about 8 to 9 in Mohs scale.
Claim 27
Dependent Claim
13 words
The method of claim 13, wherein said CMP is accomplished with a slurry.
Claim 28
Dependent Claim
13 words
The method of claim 25 wherein said slurry consists of SiO 2 particles.
Claim 29
Independent Claim
70 words
A method of forming a polish stop layer for chemical/mechanical polishing (CMP) of semiconductor wafers comprising the steps of: providing a wiring layer on said wafer; providing an oxide layer on said wiring layer; depositing a planarizing glass layer on said wiring layer; chemical/mechanical polishing (CMP) of said glass layer; ion implanting atoms in said oxide layer to form a polish stop layer; and chemical/mechanical polishing (CMP) said oxide layer.
Claim 30
Independent Claim
70 words
A method of forming a polish stop layer for chemical/mechanical polishing (CMP) of semiconductor wafers comprising the steps of: providing a wiring layer on said wafer; providing an oxide layer on said wiring layer; depositing a planarizing glass layer on said wiring layer; chemical/mechanical polishing (CMP) of said glass layer; ion implanting atoms in said oxide layer to form a polish stop layer; and chemical/mechanical polishing (CMP) said oxide layer.
Claim 31
Dependent Claim
11 words
The method of claim 27, wherein said wiring layer is aluminum-copper.
Claim 32
Dependent Claim
12 words
The method of claim 27, wherein said oxide layer is silicon oxide.
Claim 33
Dependent Claim
11 words
The method of claim 27, wherein said glass is spin-on-glass (SOG).
Claim 34
Dependent Claim
19 words
The method of claim 30 wherein said SOG is cured at a temperature between about 390° to 430° C.
Claim 35
Dependent Claim
13 words
The method of claim 27, wherein said CMP is accomplished with a slurry.
Claim 36
Dependent Claim
13 words
The method of claim 32, wherein said slurry consists of SiO 2 particles.
Claim 37
Dependent Claim
16 words
The method of claim 27, wherein said ion implanting is accomplished by means of high-energy implanter.
Claim 38
Dependent Claim
10 words
The method of claim 27, wherein said atoms are nitrogen.
Claim 39
Dependent Claim
18 words
The method of claim 35, wherein energy of said nitrogen atoms is between about 350 to 450 keV.
Claim 40
Dependent Claim
23 words
The method of claim 35, wherein the dose of said nitrogen atoms is between about 2×10 4 to 5×10 4 ions/cm 2 .
Claim 41
Dependent Claim
19 words
The method of claim 35, wherein duration for implanting said nitrogen atoms is between about 50 to 70 seconds.
Claim 42
Dependent Claim
20 words
The method of claim 35, wherein implanting depth of said nitrogen atoms is between about 9,000 to 11,000 angstroms (Å).
Claim 43
Dependent Claim
21 words
The method of claim 27, wherein said polish stop layer has a hardness between about 8 to 9 in Mohs scale.
References Cited (Backward Citations)
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