Ex Parte Hsu

Board of Patent Appeals and Interferences

Apr 28, 2009

10482876 (B.P.A.I. Apr. 28, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte CHIEN-PIN SHERMAN HSU
____________________

Appeal 2009-2630
Application 10/482,876
U.S. Patent Publication 2004/0220065
Technology Center 1700
____________________

Decided:1 April 28, 2009
____________________

Before: FRED E. McKELVEY, Senior Administrative Patent Judge,
and RICHARD E. SCHAFER and SALLY GARDNER LANE,
Administrative Patent Judges.

McKELVEY, Senior Administrative Patent Judge.

DECISION ON APPEAL
1
A. Statement of the case 2
(1) Covidien Ltd., (2) Covidien International Finance S.A., 3
(3) Tyco Group Sarl, (4) Tyco holding VII (Denmark), (5) United States 4
Surgical Corporation, (6) Mallinckrodt LLC, (7) MSCH Company and 5

1 The two-month time period (37 C.F.R. § 1.304) for filing an appeal
(35 U.S.C. § 141) or commencing a civil action (35 U.S.C. § 145) begins to
run from the decided date shown on this page of the decision. The time
period does not run from the Mail Date (paper delivery) or Notification Date
(electronic delivery).

Appeal 2009-2630
Application 10/482,876

2
(8) Mallinckrodt, Inc. ("Covidien"), the real parties in interest, seek review 1
under 35 U.S.C. § 134(a) of a final rejection (mailed 29 May 2007). 2
Claims 1, 4-5, 12, 21, 23, 25, 28-29, 36, 45 and 47 are in the 3
application. 4
Claims 25, 28-29, 36, 45 and 45 are rejected. 5
The remaining claims (1, 4-5, 12, 21 and 23) have been withdrawn 6
from consideration. 7
The Examiner relies on the following prior art: 8
Tanabe 6,225,030 01 May 2001
Skee '825 6,585,825 01 Jul 2003
Skee '370 6,599,370 29 Jul 2003
Lee 6,110,881 29 Aug 2000
Skee '448 WO 99/60448 25 Nov 1999
9
The reader should know that "et al" is not used in this opinion. 10
Covidien does not contest the prior art status of any of the five prior 11
art references cited by the Examiner. 12
We have jurisdiction under 35 U.S.C. § 134(a). 13
14
B. Findings of fact 15
The following findings of fact are supported by a preponderance of 16
the evidence. 17
References to the specification are to U.S. Patent Publication 18
2004/0220065 A1. 19

Appeal 2009-2630
Application 10/482,876

3
To the extent that a finding of fact is a conclusion of law, it may be 1
treated as such. 2
Additional findings as necessary may appear in the Discussion portion 3
of the opinion. 4
The invention 5
Covidien's invention relates to the use of compositions for cleaning 6
microelectronic substrates made using sensitive low-κ dielectrics, high-κ 7
dielectrics and copper metallization. Specification, ¶ 0001. 8
By way of background and according to Covidien, many photoresist 9
strippers and residue removers have been proposed for use in the 10
microelectronics field cleaners at the "back end" of manufacturing. 11
Specification, ¶ 0002. 12
In the manufacturing process a thin film of photoresist is deposited on 13
a wafer substrate, and then circuit design is imaged on the thin film. 14
Specification, ¶ 0002 15
Following baking, any unpolymerized resist is removed with a 16
photoresist developer. Specification, ¶ 0002 17
A resulting image is then transferred to the underlying material, which 18
is generally a dielectric or metal using an etch gas or chemical etchant 19
solution. Specification, ¶ 0002. 20
The etchant gas or chemical etchant solution selectively attacks the 21
photoresist-unprotected area of the substrate. Specification, ¶ 0002 22
As a result of the etching process, by-product materials are deposited 23
as residues around or on the sidewall of the etched openings on the substrate. 24
Specification, ¶ 0002. 25

Appeal 2009-2630
Application 10/482,876

4
After completion of the etching step, a resist mask must be removed 1
from the protected area of the wafer so that the final finishing operation can 2
take place. Specification, ¶ 0003 3
Removal can be accomplished in a plasma ashing step using, inter 4
alia, suitable wet chemical strippers. Specification, ¶ 0003. 5
According to Covidien, finding a suitable cleaning composition for 6
removal of this resist mask material without adversely affecting (e.g., 7
corroding, dissolving or dulling, the metal circuitry) has proven 8
"problematic." Specification, ¶ 0003. 9
We are not told why finding a suitable cleaning composition has been 10
"problematic," what "problematic" means, or what precise problems have 11
been encountered. 12
As microelectronic fabrication integration levels have increased and 13
patterned microelectonic device dimensions have decreased, it is said that it 14
has become increasingly common in the art to employ copper metallizations, 15
low-κ dielectrics and high-κ dielectrics. Specification, ¶ 0004. 16
Copper metallizations, low-κ dielectrics and high-κ dielectrics are said 17
to have presented additional challenges to find acceptable cleaner 18
compositions. Specification, ¶ 0004. 19
We are not told the exact nature of the "additional challenges." 20
According to Covidien, many process technology compositions that 21
have been previously developed for "traditional" or "conventional" 22
semiconductor devices containing Al/SiO2 or Al(Cu)/SiO2 structures cannot 23
be employed with copper metallized low-κ or high-κ dielectric structures. 24
Specification, ¶ 0004. 25

Appeal 2009-2630
Application 10/482,876

5
The precise nature of the "[m]any process technology compositions" 1
and how they differ from the claimed process is not clear. 2
However, Covidien tells us by way of example that hydroxylamine-3
based stripper or residue remover compositions are said to have been 4
successfully used for cleaning devices with Al metallizations, but are 5
practically unsuitable for those with copper metallizations. Specification, 6
¶ 0004. 7
Similarly, at least according to Covidien, many copper 8
metallized/low-κ strippers are not suitable for Al metallized 9
devices unless significant adjustments in the compositions are made. 10
We are not told which strippers are "unsuitable" and what adjustments 11
had to be made to make the strippers suitable. 12
According to Covidien, removal of etch or ash residues following an 13
etch or ashing process has proved "problematic." Specification, ¶ 0005. 14
We are not told why removal is "problematic." 15
Failure to completely remove or neutralize these residues is said to 16
result in (1) absorption of moisture and (2) formation of undesirable 17
materials that can cause corrosion to the metal structures. Specification, 18
¶ 0005. 19
Corrosion produces discontinuances in the circuitry wiring and 20
undesirable increases in electrical resistance. Specification, ¶ 0006. 21
Based on what we have been told up to this point, we suspect that one 22
fly in the ointment in this art is corrosion—something to be avoided. 23

Appeal 2009-2630
Application 10/482,876

6
Current "back end" cleaners are said to show a wide range of 1
compatibility with certain, sensitive dielectrics and metallizations, ranging 2
from totally unacceptable to marginally satisfactory. Specification, ¶ 0006. 3
We are not told which current back end cleaners are "unacceptable" or 4
"marginally satisfactory" and which are deemed acceptable or satisfactory. 5
For example, the specification does not reveal the nature of current 6
back end cleaners actually used in the manufacturing process using copper 7
metallization. 8
According to Covidien, many of the current strippers or residue 9
cleaners are not acceptable for advanced interconnect materials such as 10
porous and low-κ dielectrics and copper metallizations. Specification, 11
¶ 0006. 12
We are not told which of the "[m]any" strippers or residue cleaner are 13
not acceptable. Rather Covidien simply makes its "not acceptable" assertion 14
sans evidence to backup its assertion. 15
We are told, however, that the typical alkaline cleaning solutions 16
employed are overly aggressive towards porous and low-κ and high-κ 17
dielectrics and/or copper metallizations. Specification, ¶ 0006. 18
What Covidien means by "overly aggressive" is not entirely clear. 19
Moreover, many alkaline cleaning compositions are said to contain 20
organic solvents that are said to show poor product stability, especially at 21
higher pH ranges and at higher process temperatures. Specification, ¶ 0006. 22
We are not told what solvents are "poor." 23
There is, says Covidien, a need for microelectronic cleaning 24
compositions suitable for back end cleaning operations that are effective 25

Appeal 2009-2630
Application 10/482,876

7
cleaners and are applicable for stripping photoresists, cleaning residues from 1
plasma process generated organic, organometallic and inorganic materials, 2
and cleaning residues from planarization process steps, such as chemical 3
mechanical polishing and the like. Specification, ¶ 0007. 4
Covidien's invention relates to compositions that Covidien represents 5
are effective in a process for stripping photoresists, preparing/cleaning 6
semiconductor surfaces and structures. Specification, ¶ 0007. 7
The compositions are said to have good compatibility with advanced 8
interconnect materials such as low-κ dielectrics, high-κ dielectrics and 9
copper metallizations. Specification, ¶ 0007. 10
The compositions contain various ingredients, all of which are 11
apparent from the aqueous cleaning composition set out in method claim 25. 12
We reproduce claim 25 below from the Claims Appendix of the 13
Appeal Brief (received 30 October 2007) [matter in braces added; some 14
bracketed matter and indentation added]. 15
Claim 25 16
A process for cleaning a microelectronic substrate having 17
cooper metallization and at least one of 18
[1] a porous dielectric, 19
[2] a low-κ [dielectric] or 20
[3] [a] high-κ dielectric, 21
the process comprising contacting the substrate with an 22
aqueous cleaning composition for a time sufficient to clean the 23
substrate, 24

Appeal 2009-2630
Application 10/482,876

8
wherein the aqueous cleaning composition consisting 1
[sic—consists ?] of: 2
[A] from about 0.05% to 30% by weight of one or more 3
non-ammonia producing strong base 4
[1] containing non-nucleophilic, positively charged 5
counter ions and 6
[2] being a tetraalkylammonium hydroxide or salt 7
thereof of the formula 8
(R)4N+]p[X-q] { sic―[(R) 4N+]p[X-q] } 9
wherein 10
each R is independently a substituted or 11
unsubstituted alkyl group; 12
X is OH or a salt anion; and 13
p and q are equal and are integers from 1 to 3; 14
[B] from about 0.5 to about 99.95% by weight of one or 15
more corrosion inhibiting solvent compounds, said corrosion 16
inhibiting solvent compound 17
[1] having at least two sites capable of complexing 18
with metals and 19
[2] selected from the group consisting of 20
[a] ethylene glycol, 21
[b] diethylene glycol, 22
[c] glycerol, 23
[d] diethylene glycol dimethyl ether, 24
[e] triethanolamine, 25

Appeal 2009-2630
Application 10/482,876

9
[f] N-dimethylethanolamine, 1
[g] 1-(2-hydroxyethyl)-2-pyrrolidinone, 2
[h] 4-(2-hydroxyethyl) morpholine, 3
[i] N-(2-hydroxyethyl acetamide, 4
[j] N-(2-hydroxyethyl succinimide and 5
[k] 3-(diethylamino)-1,2-propanediol; 6
[C] at least one other organic co-solvent selected from 7
the group consisting of 8
[1] dimethylsulfoxide, 9
[2] sulfolane and 10
[3] dimethyl piperidone 11
in an amount of from greater than zero up to about 99.45% by 12
weight; 13
[D] from about 0 to 5% by weight of a metal chelating 14
agent selected from the group consisting of 15
[1] (ethylenedinitrilo)tetraacetic acid (EDTA), 16
[2] butylenediaminetetraacetic acid, 17
[3] (1,2-cyclohexylenedinitrilo)tetraacetic acid 18
(CyDTA) and 19
[4] aminophosphonic acids; and 20
[E] water. 21
Other claims are before the Board and, as necessary, are reproduced 22
and analyzed in the Discussion portion of our opinion. 23

Appeal 2009-2630
Application 10/482,876

10
The Examiner's rejections 1
The Examiner rejected all the claims as being unpatentable under 2
35 U.S.C. § 103 over the prior art. 3
The Examiner also rejected claims 45 and 47 as being indefinite under 4
the second paragraph of 35 U.S.C. § 112. 5
More about the nature of the rejections appears in the Discussion 6
portion of the opinion. 7
Prior art 8
(1) Tanabe—U.S. Patent 6,225,030 B1 9
The Tanabe invention relates to a post-ashing treating method for 10
substrates which is said to (1) exhibit excellent performance in treating 11
substrates having been dry-etched under strict conditions followed by ashing 12
and (2) favorable corrosion-inhibiting effects on various metallic wires and 13
metallic layers. Col. 1:7-8; col. 1:8-12. 14
According to Tanabe, semiconductor devices are fabricated by a 15
multi-step process with one step being stripping away the unwanted 16
photoresist layer. Col. 1:17-29. 17
A prior art metallic layer, for example, may be (1) aluminum (Al), 18
(2) an aluminum alloy (Al alloy), such as aluminum-silicon (Al—Si), 19
(3) aluminum-copper (Al—Cu), (4) aluminum-silicon-copper (Al―Si―Cu), 20
(5) pure titanium (Ti), (6) titanium alloy (Ti alloy), such as titanium nitride 21
(TiN) or (7) a titanium-tungsten system (TiW). Col. 1:30-35. 22
At the end of processing, resist residues, such as modified photoresist 23
films, adhere and remain in the side or bottom of patterns. Col. 1:42-44. 24

Appeal 2009-2630
Application 10/482,876

11
According to Tanabe, it is necessary to completely remove these 1
residues to avoid problems. Col. 1:46-49. 2
Tanabe reveals to one skilled in the art that the residues differ in 3
composition from one another depending, inter alia, on (1) the type of the 4
etching gas employed, (2) the ashing conditions, (3) the type of the metallic 5
layer or layers formed on the substrate and (4) the type of the photoresist 6
employed. Col. 1:50-54. 7
The residues and deposition compositions are said to have become 8
complicated, making it difficult to identify the compositions. Col. 1:56-58. 9
Due to the circumstances discussed above, and according to Tanabe, 10
no satisfactory treating liquid for residue removal has been known so far. 11
Col. 1:58-59. 12
Apparently, Tanabe would have one skilled in the art believe 13
that it was very difficult in 1998/1999 to completely remove residues. 14
Col. 1:59-62. 15
An object of the Tanabe invention is to provide a post-ashing treating 16
method for substrates that exhibits excellent effects of removing resist 17
residues such as modified photoresist films and metal depositions and also 18
exerts favorable corrosion-inhibiting effects on the substrates. Col. 2:12-14. 19
Consistent with the Tanabe description of the prior art, the Tanabe 20
process comprises the following six steps: 21
(1) forming a photoresist layer on a substrate having metallic 22
layer or layers; 23
(2) selectively exposing the photoresist layer to light; 24

Appeal 2009-2630
Application 10/482,876

12
(3) developing the light-exposed photoresist layer to provide a 1
photoresist pattern; 2
(4) etching the substrate through the photoresist pattern as a 3
mask pattern to form a metallic wired pattern; 4
(5) ashing the photoresist pattern; and 5
(6) after the completion of the ashing, bringing the substrate 6
into contact with a treating liquid composition to thereby treat 7
the substrate (apparently to remove residue). 8
Col. 2:19-34. 9
Insofar as the appeal is concerned, it is Step (6) which is significant. 10
The Tanabe treating liquid composition used in Step (6) is described 11
as being a composition having the following ingredients: 12
(a) 0.5-10 wt % of a lower alkyl quaternary ammonium salt; 13
(b) 1-50 wt % of a polyhydric alcohol; and 14
(c) water as the balance. 15
Col. 2:36-38; Col. 2:46-49. 16
"[P]referably" Tanabe component (a) is tetramethylammonium 17
hydroxide (TMAH) [the salt mentioned in Covidien's claims 45 and 47] or 18
choline. Col. 2:57-58. 19
As Tanabe polyhydric alcohol component (b), it is preferable to use 20
one or more members selected from the group consisting of (1) glycerol 21
[mentioned in Covidien claim 25], (2) ethylene glycol [mentioned in 22
Covidien claim 25], (3) propylene glycol, (4) 1,2-butylene glycol, 23
(5) 1,3-butylene glycol and (6) 2,3-butylene glycol. Col. 2:61-64. 24
Glycerol is said to be particularly preferred. Col. 64-65. 25

Appeal 2009-2630
Application 10/482,876

13
Water is used as Tanabe component (c). 1
In addition to components (a), (b) and (c), Tanabe also teaches that the 2
treating liquid compositions may further contain, inter alia, water-soluble 3
organic solvents, surfactants, etc., as long as adverse effects do not result. 4
Col. 3:22-25. 5
Examples of the water-soluble organic solvents include: 6
(1) sulfoxides, such as dimethylsulfoxide [mentioned in Covidien claims 25 7
and 47]; (2) sulfones, (3) amides, (4) lactams and (5) imidazolidinones. 8
Col. 3:26-37. 9
Various metallic layers may be used, "for example" (1) aluminum 10
(Al), (2) an aluminum alloy (Al alloy), such as aluminum-silicon (Al―Si), 11
(3) aluminum-copper (Al―Cu) or (4) aluminum-silicon-copper 12
(Al―Si―Cu), (4) pure titanium (Ti), (5) a titanium alloy (Ti alloy), such 13
as titanium nitride (TiN) or (6) a titanium-tungsten system (TiW). 14
Col. 3:58-63. 15
The Tanabe treating liquid compositions are said to be particularly 16
effective in (1) removing residues and (2) minimizing corrosion in metallic 17
layers. Col. 4:1-4. 18
Tanabe Table 1 is reproduced below. 19

Appeal 2009-2630
Application 10/482,876

14
1
In Table 1: 2
(1) TMAH stands for tetramethylammonium hydroxide; 3
(2) GLY stands for glycerol; 4
(3) CHOL stands for (2-hydroxyethyl)trimethylammonium 5
hydroxide; and 6
(4) EG represents ethylene glycol. 7
Examples 1-6 in Table 1 (col. 6) describe mixtures of TMAH, 8
glycerol and water. According to Tanabe, each of the mixtures of Examples 9
1-4 and 6 exhibited "no corrosion" (as represented by the â—‹). The mixture of 10
Example 5 showed "slight corrosion" (as represented by the Ù¨) for 11
AL―Si―Cu. Use of or glycerol or TMAH alone did not fare well (as 12
represented by the X) in some instances. 13

Appeal 2009-2630
Application 10/482,876

15
Tanabe differs from claim 25 in that Tanabe does not (1) explicitly 1
describe the use of its treating liquid compositions for removing residue 2
from a microelectronic substrate having cooper metallization and (2) does 3
not describe the amount of water-soluble organic solvent to be used when a 4
solvent is used. 5
(2) The Skee references 6
The Examiner relies on three Skee references. Two are U.S. Patents 7
(6,585,825 B1 and 6,599,370 B2) and one is a published International 8
Application (WO 99/60448). 9
The Examiner relies on each reference alternatively in combination 10
with Tanabe. 11
Skee 6,599,370 was relied upon, inter alia, to show that it was known 12
in the art to use treating liquid compositions (which admittedly are different 13
from the treating liquid composition of Tanabe) on semiconductor wafers 14
which contain copper or titanium (Examiner's Answer, page 6) (italics 15
added): 16
The method of the present invention is very effective for 17
cleaning semiconductor wafer substrates that have been 18
previously oxygen plasma ashed to remove bulk photoresist, 19
particularly wafer substrates containing a silicon, silicon oxide, 20
silicon nitride, tungsten, tungsten alloy, titanium, titanium 21
alloy, tantalum, tantalum alloy, copper, copper alloy, aluminum 22
or aluminum alloy film. The method removes unwanted 23
metallic and organic contaminants but does not cause 24
unacceptable corrosion to the silicon, silicon oxide, silicon 25

Appeal 2009-2630
Application 10/482,876

16
nitride, tungsten, tungsten alloy, titanium, titanium alloy, 1
tantalum, tantalum alloy, copper, copper alloy, aluminum or 2
aluminum alloy film. 3
Col. 13:27-38. See also Skee (6,585,825 B1), col. 9:56-67. 4
Skee reveals that water-soluble organic solvents may be present in the 5
residue removing compositions: 6
The compositions … may also contain one or more 7
suitable water-soluble organic solvents. Among the various 8
organic solvents suitable are alcohols, polyhydroxy alcohols, 9
glycols, glycol ethers, alkyl-pyrrolidinones such as 10
N-methylpyrrolidinone (NMP), 1-hydroxyalkyl-2-11
pyrrolidinones such as 1-(2-hydroxyethyl)-2-pyrrolidinone 12
(HEP), dimethylformamide (DMF), dimethylacetamide 13
(DMAc), sulfolane, dimethyl-2-piperidone (DMPD) or 14
dimethylsulfoxide (DMSO). These solvents may be added to 15
reduce aluminum and/or aluminum-copper alloy and/or copper 16
corrosion rates if further aluminum and/or aluminum-copper 17
alloy and/or copper corrosion inhibition is desired. Preferred 18
water-soluble organic solvents are polyhydroxy alcohols such 19
as glycerol and/or 1-hydroxyalkyl-2-pyrrolidinones such as 20
1-(2-hydroxyethyl)-2-pyrrolidinone (HEP). 21
22
Col. 9:1-16. See also Skee (6,585,825 B1), col. 7:1-14. 23
Skee further reveals that the residue removing compositions may 24
include a suitable metal chelating or complexing agent to increase the 25
capacity of the formulation to retain metals in solution and to enhance the 26
dissolution of metallic residues on a wafer surface. Col. 8:20-24. See also 27
Skee (6,585,825 B1), col. 6:38-42. 28
Included among the suitable metal chelating or complexing agents 29
are: 30

Appeal 2009-2630
Application 10/482,876

17
(1) (ethylenedinitrilo)tetraacetic acid (EDTA), 1
(2) butylenediaminetetraacetic acid, 2
(3) (1,2-cyclohexylenedinitrilo)tetraacetic acid (CyDTA), and 3
(4) various aminophosphonic acids, e.g., (a) (N,N,N',N'-4
ethylenediaminetetra(methylenephosphonic)acid (EDTMP), 5
(b) 1,5,9-triazacyclododecane-N,N',N"-tris(methylene-6
phosphonic acid) (DOTRP), (c) 1,4,7,10-tetraaza-7
cyclododecane-N,N',N",N'"-tetrakis(methylenephosphonic 8
acid) (DOTP), (d) nitrilotris(methylene)triphosphonic acid, and 9
(e) diethylenetriaminepenta(methylenephosphonic acid) 10
(DETAP). 11
Col. 8:20-59. See also Skee (6,585,825 B1), col. 6:38-60. 12
Skee (WO 99/60448) also describes a need for a residue removing 13
composition in the wafer making process. 14
Skee (WO 99/60448), like the other prior art before us, states that 15
none of the compositions disclosed in the prior art effectively remove all 16
organic contamination and metal-containing residues after a typical etching 17
process. Page 6:16-17. 18
Accordingly, it is alleged that there is a need for stripping 19
compositions that clean semiconductor wafer substrates by removing 20
metallic and organic contamination from the substrates without damaging 21
integrated circuits forming part of the wafer. Page 6:17-30. 22
The composition must not corrode the metal features that partially 23
comprise the integrated circuit. Page 6:20-22. 24

Appeal 2009-2630
Application 10/482,876

18
An object of the Skee (WO 99/60448) invention is to come up with a 1
composition useful in the microelectronics industry for cleaning 2
semiconductor wafer substrates without damaging the substrates. 3
Page 6:24-28. 4
The compositions may include metal chelating agents. Page 10:3-15. 5
The compositions may also include one or more water soluble 6
solvents, including glycerol, sulfolane and dimethyl sulfoxide. 7
Page 10:21-30. 8
The solvents are added to reduce aluminum or aluminum-copper alloy 9
or copper corrosion rates where further corrosion inhibition is desired. 10
Page 10:26-28. 11
The composition is said to be useful on a wide variety of wafer, 12
including those made using aluminum, aluminum alloy, copper and copper 13
alloy. Page 15:8-15. 14
(3) Lee—U.S. Patent 6,110,881 15
Lee also describes residue removal solutions. 16
Lee, like the other prior art, reveals that during etching processing, an 17
organometallic by-product compound can be formed on the sidewall of the 18
substrate material. Col. 1:55-57. 19
According to Lee: 20
During the fabrication of microcircuits, the precise positioning 21
of a number of appropriately doped regions on a slice of 22
semiconductor is required followed by the positioning of one or 23
more interconnection patterns on the semiconductor. Positive-24
type resists have been extensively used as masking materials to 25
delineate patterns onto a substrate so that the patterns can be 26
subsequently etched or otherwise defined into the substrate. 27

Appeal 2009-2630
Application 10/482,876

19
The final steps in preparing the substrate then involve removing 1
the unexposed resist material and any etching residue from the 2
substrate. Increasingly, however, plasma etching, reactive ion 3
etching or ion milling is used to define the pattern in a substrate 4
which renders the resist mask substantially impossible to 5
remove by stripping agents heretofore commonly used for such 6
or similar purposes containing one or more of the following 7
solvents: halogenated hydrocarbons such as, for example, 8
methylene chloride or tetrachloroethylene; amines and their 9
derivatives such as, for example, dimethylformamide, 10
dimethylacetamide, pyrrolidone, diethanolamine, and 11
triethanolamine; glycol ethers, such as, for example, ethylene 12
glycol monoethyl ether, 2-butoxyethanol, and 2-(butoxy-13
ethoxy)ethanol; and an alkylsulfone, such as, for example, 14
dimethylsulfone. 15
16
Col. 1:32-54. 17
Prior art solvents are said to be ineffective in removing organometallic 18
polymer formed on the sidewall of the substrate during the etching process. 19
Col. 1:57-59. 20
Lee reveals that: 21
a composition suitable for stripping a resist so as to remove the 22
resist rapidly and completely would provide substantial 23
advantages over conventional strippers. Further, a composition 24
capable of removing both the resist and organometallic 25
by-products would provide even a greater advantage. As 26
apparent, if an etching residue is not completely removed from 27
the substrate, the residue can interfere with subsequent 28
processes involving the substrate. 29
30
Col. 2:11-18. 31

Appeal 2009-2630
Application 10/482,876

20
According to Lee (italics added): 1
In addition to removing completely the resist material, 2
particularly with the introduction of submicron process 3
techniques to form wafers, there is a demand for cleaning 4
technology for removing etching residue remaining following 5
resist removal. The requirement for a cleaning solution to 6
remove all types of residue generated as a result of plasma 7
etching of various types of metals, such as aluminum, 8
aluminum/silicon/copper, titanium, titanium nitride, 9
titanium/tungsten, tungsten, silicon oxide, polysilicon crystal, 10
etc., presents a need for more effective cleaning chemistry in 11
the processing area. 12
13
Col. 2:19-29. 14
Lee describes an invention that is directed to resist and etching residue 15
removing compositions comprising (1) at least one nucleophilic amine 16
compound which possesses reduction and oxidation potentials, (2) at least 17
one organic solvent which is miscible with the nucleophilic amine, (3) water 18
and, (4) optionally, one or more chelating agents. The solutions are said to 19
be useful in removing resists and etching residue from microcircuitry during 20
fabrication processes. Col. 1:21-28; col. 4:9-17. 21
Lee describes the use of a variety of suitable organic solvents (italics 22
added). 23
Organic solvents suitable for use in the present invention 24
are miscible with the nucleophilic amine compound and are 25
preferably water-soluble. Additionally, the organic solvent 26
useful in the present invention preferably has a relatively high 27
boiling point, such as for example 100 ºC. or above, and a high 28
flash point, such as for example 45 ºC. or above. 29
30

Appeal 2009-2630
Application 10/482,876

21
Suitable organic solvents include alkanolamines and their 1
derivatives. Additionally, non-amine solvents, such as 2
dimethyl sulfoxide (DMSO), are suitable for use. Preferably an 3
amine solvent is present alone or in combination with another 4
solvent. Previously, it had been believed that an alkanolamine 5
solvent had to be utilized. While an alkanolamine solvent is 6
still a preferred solvent, it has now been found that other 7
solvents are suitable for use when utilized with at least one 8
nucleophilic amine compound having reduction and oxidation 9
potentials. 10
11
Suitable alkanolamines are primary, secondary or tertiary 12
amines and are preferably monoamines, diamines or triamines, 13
aminoalkoxyalkanols and, most preferably, monoamines. The 14
alkanol group of the amines preferably has from 1 to 5 carbon 15
atoms. 16
17
Col. 8:37-56. 18
An example of a suitable alkanolamine is triethanolamine. Col. 8:63. 19
Examples of alternative organic solvents suitable for use in the 20
composition of the Lee invention include ethylene glycol. Additional polar 21
solvents as known in the art can also be used in the composition of the 22
present invention. Col. 9:1-10. 23
According to Lee, examples of substrates from which the stripping 24
and cleaning compositions of the Lee invention remove photoresists without 25
attacking the substrates themselves include metal substrates such as 26
aluminum, titanium/tungsten, aluminum/silicon, aluminum/silicon/copper; 27
and substrates such as silicon oxide, silicon nitride, and gallium/arsenide; 28
and plastic substrates such as polycarbonate. Col. 10:6-11. 29

Appeal 2009-2630
Application 10/482,876

22
(4) Van Zant—Microchip Fabrication 1
Covidien cites and relies on Van Zant, Microchip Fabrication, 2
Chapter 13, pages 389-399, McGraw-Hill (1998). 3
In the appeal brief, Covidien did not favor the Board with the 4
publication date of Van Zant. We went surfing on the internet and found 5
that it was published in 1998. Van Zant is prior art under 35 U.S.C. § 102(b) 6
assuming—without deciding—that Covidien is entitled to its PCT 7
application and provisional application filing dates. We are at a loss to 8
figure out why a Van Zant publication date was not cited in the Appeal 9
Brief. 10
Van Zant reveals that aluminum had emerged as the preferred metal 11
for making microchips because it was said to avoid certain problems. Van 12
Zant, page 391. 13
However, it turns out that there were problems with aluminum and the 14
art then developed aluminum-silicon (Al―Si) interfaces. Id. 15
The problems apparently did not end with aluminum-silicon 16
interfaces. There came a time when aluminum-copper was discovered and 17
was said "to resolve both alloying and electromigration problems." Id at 18
393, first incomplete paragraph. 19
This brings us to copper. Copper is a better conductor than aluminum. 20
Id. at 397, second full paragraph. 21
However, even copper is said to have "etching problems, vulnerability 22
to scratching and corrosion and a need for barrier metals to keep the copper 23
out of any silicon. Id. 24

Appeal 2009-2630
Application 10/482,876

23
According to Van Zant (italics added): 1
Research is underway [as of 1998] on copper metallization with 2
new low-capacitance (lower dielectric strength or low κ) 3
dielectrics, such as cobalt silicide (CoSi2). Switching to a 4
copper metal system and a low κ dielectric could lower the RC 5
constant by 400 percent. 6
7
C. Discussion 8
Examiner’s § 112 rejection 9
Since 1948, "consisting of" and "comprising" have had well 10
established meanings in patent law when used in claims. Ex parte Davis, 11
80 USPQ 448, 450 (Bd. App. 1948). 12
Claim 25 is reproduced above. 13
Claim 45 reads (italics added): 14
A process of claim 25 wherein the cleaning composition 15
comprises tetramethylammonium hydroxide, triethanolamine, 16
trans-1,2-cyclohexanediamine tetraacetic acid, sulfolane and 17
water. 18
The Examiner understandably says "comprising" causes confusion.19
Covidien responding, in effect, says that the "applicant" gets to choose 20
how to write its claims. As long as the claim is definite, Covidien has a 21
point. 22
The claims under consideration (45 and 47) are undergoing 23
examination—not an infringement case analysis. The standard for 24
compliance with the "particularly pointing out and distinctly claiming" 25
provision of 35 U.S.C. § 112, second paragraph, while an application is 26

Appeal 2009-2630
Application 10/482,876

24
pending is justifiably stricter than in infringement cases. A claim 1
undergoing examination can, and should, be amended to clear up even minor 2
ambiguities. 3
The Federal Circuit has observed that an essential purpose of patent 4
examination is to fashion claims that are precise, clear, correct, and 5
unambiguous. The Federal Circuit goes on to state that only in this way can 6
uncertainties of claim scope be removed, as much as possible, during the 7
administrative process. In re Zletz, 893 F.2d 319, 322 (Fed. Cir. 1989). 8
Consistent with Zletz, the Federal Circuit subsequently noted that a 9
different standard for indefiniteness may be appropriate during prosecution 10
of patent claims. See Exxon Research and Engineering Co. v. United States, 11
265 F.3d 1371, 1384 (Fed. Cir. 2001) (If the claims under consideration in 12
the infringement appeal were before an examiner, the examiner might well 13
be justified in demanding that the applicant more clearly define UL, and 14
thereby remove any degree of ambiguity. However, the court was faced 15
with an issued patent that enjoys a presumption of validity. Accordingly, the 16
court adopted a lower threshold standard of ambiguity for indefiniteness for 17
claims during prosecution in keeping with the USPTO's broadest reasonable 18
interpretation standard for claim construction).2 19

2 While not precedent, we note the following observation by Federal
Circuit Judge Richard Linn made in his keynote address to the USPTO
Society Annual Meeting on 18 Feb. 2009: "[t]he public's interest is well-
served when the meaning of all of the terms used in the claims does not have
to be inferred but is unambiguous and capable of discerning explicitly from
the written description and prosecution history."

Appeal 2009-2630
Application 10/482,876

25
As the Examiner pointed out, dependent claims 45 and 47 expand the 1
scope of independent claim 25, which is not "ok" with the fourth paragraph 2
of 35 U.S.C. § 112. Pfizer, Inc. v. Ranbaxy Laboratories Limited, 457 F.3d 3
1284, 1292, 79 USPQ2d 1583, 1590 (Fed. Cir. 2006) ("Although the district 4
court was reluctant to find the fourth paragraph of § 112 to be an 5
invalidating provision, doing so does not exalt form over substance. Rather, 6
it is consistent with the overall statutory scheme that requires applicants to 7
satisfy certain requirements before obtaining a patent, some of which are 8
more procedural or technical than others.") 9
Claim 25 says the aqueous cleaning composition "consisting of" and 10
proceeds to thereafter list five ingredients, which we have set out as 11
elements [A] through [E] in claim 25 as reproduced above. The language 12
"consisting of" is not proper English. What we think Covidien means is 13
"consists of." We overlook the language problem because in patent law 14
"consists of" and "consisting of" mean exactly the same thing. 15
The aqueous cleaning composition used in the process of claim 25 is 16
made up of elements [A] through [E] and impurities ordinarily associated 17
with those element. Ex parte Davis, 80 USPQ at 450. 18
Claims 45 and 47, which are supposed to narrow the scope of 19
claim25, say the aqueous cleaning composition "comprises" one species of 20
each of elements [A] through [E]. However, use of "comprises" opens a 21
claim to inclusion of unspecified ingredients. Id. 22
Covidien asserts that there is no problem because claim 45 has to be 23
interpreted in view of claim 25. Not so where there is ambiguity. 24

Appeal 2009-2630
Application 10/482,876

26
There is a clear tension between the "consisting of" of claim 25 and 1
the "comprising" of claims 45 and 47. A "comprising" dependent claim 2
cannot open up the scope of a "consisting of" independent claim without 3
causing potential confusion. 4
We see no reason to issue a patent with the language of claims 45 and 5
47 and thereby transfer to potential competitors and Federal Courts the chore 6
of having to figure out the claims. 7
In the event of an RCE or a continuation, Covidien can take steps 8
necessary to eliminate any confusion. 9
The decision of the Examiner making a rejection under the second 10
paragraph of 35 U.S.C. § 112 is affirmed. 11
Examiner's § 103 rejection 12
(1) What is the precise state of the art in the microchip industry? 13
We would be less than forthright if we did not say we are somewhat 14
confused by the mixed messages about state of the prior art which surface in 15
the prior art which has been presented in the appeal. 16
An objective evaluation by a disinterested third-party (that would be 17
the Board) can lead to a belief that nothing in the prior art "works." 18
In date chronological order we start with Lee. Lee says that prior art 19
solvents are ineffective in removing organometallic polymer formed on the 20
sidewall of the substrate during the etching process. Col. 1:57-59. Lee, of 21
course, asserts that it has a solution to the "ineffective" removal. 22
Next comes Tanabe. Tanabe could be read as implying that nothing 23
"works"—at least nothing works satisfactorily: "no satisfactory treating 24

Appeal 2009-2630
Application 10/482,876

27
liquid for residue removal has been known so far." Col. 1:58-59. Like Lee, 1
Tanabe claims to have solved the problem. 2
Next come the Skee U.S. Patents and the Skee published International 3
application (WO 99/60448). Some of the Skee documents treat the prior art 4
with little, if any, respect. For example, none of the compositions disclosed 5
in the prior art are said to effectively remove organic contamination and 6
metal-containing residues remaining after a typical etching process. Skee 7
(WO 99/60448), page 6:16-17. 8
Skee 6,599,370 says that Skee (WO 99/60448), while said to have 9
solved some problems fails to overcome other problems. Col. 3:58-63: 10
"Although the compositions disclosed in WO 9960448 effectively remove 11
all organic contamination and metal-containing residues remaining after a 12
typical etching process, these compositions have a relatively short bath life. 13
There is, therefore, a need for similar compositions with very long bath lives 14
exceeding twenty hours." 15
If one is to believe the "objects" of the Skee 6,585,825 invention 16
(col. 3:49 through col. 4:4), Skee 6,585,825 solves numerous problems 17
which are said to have existed as late as 2000: 18

Appeal 2009-2630
Application 10/482,876

28
It is another object of the present invention to provide 1
compositions that remove metallic and organic contamination 2
from semiconductor wafer substrates without damaging the 3
integrated circuits. 4
5
It is another object of the present invention to provide 6
compositions that have very long effective bath lives. 7
8
It is a further object of the present invention to provide a 9
method for cleaning semiconductor wafer substrates that 10
removes metallic and organic contamination from such 11
substrates without damaging the integrated circuits and 12
avoiding the expense and adverse consequences caused by 13
intermediate rinses. 14
15
These and other objects are achieved using new aqueous 16
compositions for stripping or cleaning semiconductor wafer 17
substrates that contain one or more metal ion-free bases and a 18
bath stabilizing agent. The compositions are placed in contact 19
with a semiconductor wafer substrate for a time and at a 20
temperature sufficient to clean unwanted contaminants and/or 21
residues from the substrate surface. 22
Col. 3:52 through col. 4:4. 23
Not only do the prior art patents seem to suggest that little, if 24
anything, in the "earlier" prior art is worthwhile (presumably from a 25
commercial point of view), but each proposes a solution and proceeds to 26
claim solutions in fairly broad terms. 27
The current application likewise does not treat the prior art with much 28
respect. It describes prior art solutions as "problematic" without saying why. 29
See, e.g., Specification, ¶ 0003. Covidien then gives the impression that it—30
like Lee, Tanabe and Skee—has solved prior art problems. 31

Appeal 2009-2630
Application 10/482,876

29
Covidien does not deny that copper metallization microelectronic 1
substrates have been made and sold. Specification, ¶ 0004. What we are not 2
told is how residue was removed in the manufacturing process actually used 3
to make the products on the market at the time Covidien made the invention. 4
Because microchips have been sold, we have to assume that someone 5
did something right. Microchip manufacturers are not in the business of 6
loosing money or selling "problematic" products. 7
"Stories" in documents filed as patent applications in which a patent 8
applicant attempts to paint its current invention in a light most favorable to 9
the applicant, while at the same time degrading or minimizing the prior art, 10
causes us to wonder what, if anything, actually "worked" satisfactorily in the 11
past. We are not entirely comfortable with our understanding of what 12
actually occurred in industry prior to Covidien's invention. Worthwhile 13
advances in microchip technology surely must occur on a regular basis. 14
However, we find it hard to believe that everything that went on before is 15
"bad" simply because something better is said to come a long later in time. 16
We find it difficult, if not impossible, to credit the prior art "stories" in 17
the specification and the prior art before us and we decline to do so. 18
(2) Analysis on the "merits" 19
Claims 25 and 28-29 stand or fall together on the obviousness 20
issue. Appeal Brief, page 15. We will consider claim 25. 37 C.F.R. 21
§ 41.37(c)(1)(vii). 22
Like the Examiner, we will start with Tanabe. 23
Tanabe found a residue cleaning solution which Tanabe seems to 24
think is pretty good. 25

Appeal 2009-2630
Application 10/482,876

30
Tanabe's prior art date is 1999, but as the Tanabe patent reveals, 1
Tanabe filed a patent application in Japan in 1998—more or less around the 2
time Van Zant tells us that copper metallization "could" lead to significant 3
improvements. 4
Tanabe describes an aqueous residue cleaning solution which can 5
have the same ingredients in the same amounts as that used in Covidien's 6
claim 25 process. Tanabe describes a residue cleaning composition having 7
elements [A], [B] and [E] of claim 25. Element [D] of claim 25 is optional, 8
although the prior art of record reveals use of Element [D] materials is 9
known and are common used in the art. Element [C] is a co-solvent. 10
Tanabe reveals optional use of a co-solvent. Col. 3:23-39. To be 11
sure, Tanabe does not say why it recommends optional use of a solvent. 12
But, Skee provides a reason for using a solvent. Skee, WO 99/60448, 13
page 10, lines 26-28: reduced corrosion—one of the objects of Covidien's 14
invention. The prior art reveals that those skilled in the art know that a 15
co-solvent can be included in residue cleaning compositions. With respect 16
to the amount of solvent called for the Covidien's residue cleaning solution, 17
it would be hard to imagine that one skilled in the art would not be able to 18
determine an appropriate amount gives its ubiquitous use in the art. 19
Another difference between Tanabe and the subject matter of claim 25 20
is that Tanabe does not explicitly describe the use of its residue cleaning 21
compositions in the copper metallizing environment. Covidien views this 22
difference as significant and the point on which the appeal should be 23
resolved. More particularly, Covidien is content to argue the difference and 24
to point out (via Van Zant) that the microchips of Tanabe differ in some 25

Appeal 2009-2630
Application 10/482,876

31
significant manner from those of Tanabe. Relying on its background of the 1
invention, which in large measure we decline to credit, Covidien attempts to 2
paint a picture that one skilled in the art would not have even thought about 3
using the Tanabe residue cleaning compositions for copper metallizing 4
embodiments. 5
Overlooked by Covidien is the fact that Tanabe does not restrict the 6
use of the described residue cleaning compositions to particular microchip 7
environments. Rather, Tanabe while setting out specific embodiments 8
where the compositions might be used, Tanabe states that those 9
embodiments are "for example." Col. 1:30-36. We cannot help but note that 10
some of those "examples" include copper based microchips. Nothing in 11
Tanabe says one skilled in the art should not use the Tanabe residue cleaning 12
composition in a copper metallization environment. 13
The Skee documents also reveal that residue cleaning compositions 14
can be used to clean up a wide range of microchips. 15
What surfaces from the prior art as a whole, is that Covidien is using a 16
known or obvious composition for a known purpose to obtain a predictable 17
result. Under the circumstances, KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 18
417-18, 127 S. Ct. 1727, 1740 (2007), counsels against non-obviousness. 19
Where a technique (use of Tanabe's residue cleaning composition) to 20
improve one device (the microchips of Tanabe) and one skilled in the art 21
would recognize that it would improve similar devices, KSR again counsel's 22
against non-obviousness. 550 U.S. at 417; 127 S. Ct. at 1740. See also In re 23
Sullivan, 498 F.3d 1345, 1351 (Fed. Cir. 2007) (compound known to 24
neutralize venom of one snake found to be obvious to neutralize venom of 25

Appeal 2009-2630
Application 10/482,876

32
different snake). We have not been able to find a convincing reason why 1
one skilled in the art, aware of pre-copper metallizing chips in need of 2
cleaning, would not have seriously considered the Tanabe residue cleaning 3
compositions for preparing copper metallizing microchips. 4
Claims 36, 45 and 47 stand or fall together on the obviousness issue. 5
Appeal Brief, page 20. 6
Claims 45 and 47 have been held to be indefinite. Ordinarily, we do 7
not reach the obviousness of an indefinite claim. In re Steele, 49 CCPA 8
1295, 1300, 305 F.2d 859, 862-63 (CCPA 1962). In order to resolve 9
patentability over the prior art, the Examiner treated the "comprising" of 10
claims 45 and 47 as being "consisting of." Examiner's Answer, page 3. We 11
will do likewise and reach the merits of the § 103 issue before us. 12
We will consider claim 36 to resolve the patentability over the prior 13
art of claims 36, 45 and 47. 37 C.F.R. § 41.37(c)(1)(vii). 14
Claim 36 limits corrosion inhibiting solvent (element [B] of claim 25) 15
to triethanolamine. 16
Tanabe does not describe the use of triethanolamine. Rather, Tanabe 17
describes broadly the use of "polyhydric alcohols" (col. 2:47) and provides 18
various examples of suitable alcohols, including ethylene glycol (col. 2:63). 19
Triethanolamine, of course, is a known polyhydric alcohol. However, based 20
on that fact alone, we would find it difficult to find obviousness. See, e.g., 21
In re Jones, 958 F.2d 347, 350 (Fed. Cir. 1992). But, the Examiner has also 22
cited Lee. 23
Lee describes residue cleaning compositions for use in the 24
manufacture of microchips. The microchips are different from those of 25

Appeal 2009-2630
Application 10/482,876

33
Tanabe. However, Lee describes the use of an organic solvent in the residue 1
cleaning compositions. Among the solvents which can be used are 2
polyhydric alcohols—both amino polyhydric alcohols (col. 8:62-67) and 3
non-amino polyhydric alcohols (col. 9:1-10). The amino polyhydric 4
alcohols include triethanolamine (col. 8 63). The non-amino polyhydric 5
alcohols include ethylene glycol (col. 9:4). What is common about the 6
Tanabe and the Skee documents, on the one hand, and Lee, on the other 7
hand, is the need for a solvent. 8
According to Lee, the organic solvent is not required to be an amine, 9
but the presence of an amine solvent is said to be preferred for Lee's 10
purpose. Col. 4:38-39. What is significant is that useful organic solvents 11
preferably have a relatively high boiling point, such as for example 100 ºC. 12
or above, and a high flash point, such as for example 45ºC. or above. 13
Col. 8:39-42. One complaint Covidien has with the prior art is that certain 14
solvents did not work well at "higher process temperatures." Specification, 15
¶ 0006. One skilled in the art would appreciate that use of relatively high 16
boiling and flash points would overcome the "complaint." 17
Preferences of Lee aside, the residue cleaning art is aware of 18
(1) the use of triethanolamine as a solvent in residue cleaning 19
compositions, 20
(2) triethanolamine is a polyhydric alcohol, 21
(3) Tanabe describes the use of polyhydric alcohol solvents, 22
including ethylene glycol, for residue cleaning compositions, 23
(4) ethylene glycol is a polyhydric alcohol, 24

Appeal 2009-2630
Application 10/482,876

34
(5) Lee describes the use of both triethanolamine and ethylene 1
glycol as alternative and useful solvents in residue cleaning 2
compositions and 3
(6) there is no reason to expect that triethanolamine would not 4
function in Tanabe in essentially the same manner, and for the 5
same purpose, in the Tanabe residue cleaning compositions. 6
It is true as Covidien argues that the Lee composition is different from 7
the Tanabe and Skee compositions. But, what the Examiner relies on is the 8
prior art teaching of the use of both ethylene glycol and triethanolamine as 9
known solvents in residue cleaning compositions. Covidien tries to isolate 10
(1) one relied upon prior art reference (Lee) from (2) the other relied upon 11
references (Tanabe and the Skee documents) thereby seeking to avoid the 12
effect of the prior art as a whole. Covidien, however, is using a known 13
solvent (triethanolamine described by Lee) in a known manner consistent 14
with the "polyhydric alcohol" teaching of Tanabe. Covidien does reveal in 15
the Appeal Brief why triethanolamine is "critical" or that it somehow results 16
in something unpredictable. Under the circumstances, Covidien has not 17
shown that the Examiner erred. 18
We have considered Covidien’s remaining arguments and find none 19
that warrant reversal of the Examiner’s rejections. Cf. Hartman v. 20
Nicholson, 483 F.3d 1311, 1315 (Fed. Cir. 2007). 21

Appeal 2009-2630
Application 10/482,876

35
D. Decision 1
Covidien has not sustained its burden on appeal of showing that the 2
Examiner erred in rejecting the claims on appeal as being unpatentable under 3
§ 112 or over the prior art. 4
On the record before us, Covidien is not entitled to a patent containing 5
claims 25, 28-29, 36, 45 or 47. 6
Upon consideration of the appeal, and for the reasons given herein, 7
it is 8
ORDERED that the decision of the Examiner rejecting 9
claims 45 and 47 as being indefinite is affirmed. 10
FURTHER ORDERED that the decision of the Examiner 11
rejecting claims 25, 28-29, 36, 45 and 47 as being unpatentable over the 12
prior art is affirmed. 13
FURTHER ORDERED that no time period for taking any 14
subsequent action in connection with this appeal may be extended under 15
37 C.F.R. § 1.136(a)(1)(iv) (2008). 16

AFFIRMED

ack

cc:

Mallinckrodt Inc.
675 McDonnell Boulevard
HAZELWOOD MO 63042