Ex Parte Yu et al

Patent Trial and Appeal Board

Jun 9, 2016

12701104 (P.T.A.B. Jun. 9, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
121701, 104 02/05/2010
7590
David M, O'Dell
Attorney for Applicants
Haynes and Boone, LLP
06/09/2016
2323 Victory A venue, Suite 700
Dallas, TX 75219
FIRST NAMED INVENTOR
Vincent Yu
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
2009-0607/ 24061.1387 9308
EXAMINER
LEE, JAE
ART UNIT PAPER NUMBER
2899
MAILDATE DELIVERY MODE
06/09/2016 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte VINCENT YU, SHIH-CHE WANG, and
CHUN-KUANG CHEN
Appeal2014-008755
Application 12/701, 104
Technology Center 2800
Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and
JAMES C. HOUSEL, Administrative Patent Judges.
PERCURIAM.
DECISION ON APPEAL 1
STATEMENT OF THE CASE
Appellants2 filed an appeal under 35 U.S.C. § 134 from the
Examiner's decision finally rejecting claims 1-19 and 21. We have
jurisdiction under 35 U.S.C. §§ 6(b) and 134(a).
We AFFIRM.
1 Our decision refers to the Final Office Action mailed Mar. 19, 2013 (Final
Act.), Appellants' Appeal Brief filed February 7, 2014 (Appeal Br.), the
Examiner's Answer mailed June 11, 2014 (Ans.), and Appellants' Reply
Brief filed Aug. 7, 2014 (Reply Br.).
2 Appellants identify the real party in interest as Taiwan Semiconductor
Manufacturing Company, Ltd. Appeal Br. 3.
Appeal2014-008755
Application 12/701, 104
The claims on appeal are directed to methods in which a positive
photoresist layer is formed on a semiconductor substrate, the positive
photoresist layer is exposed to radiation, and the positive photoresist layer is
developed via a negative tone developer to remove unexposed portions of
the positive photoresist layer to form a hole pattern (see, e.g., claims 1, 13,
and 21).
Independent claim 1 is illustrative of the subject matter on appeal.
Claim 1 is reproduced from the Claims Appendix of the Appeal Brief with
limitations at issue in the appeal italicized:
1. A method of fabricating a device using an exposure source
compnsmg:
forming a positive photoresist layer on a semiconductor
substrate, the semiconductor substrate having no patterned
photoresist layer thereon prior to forming the positive photoresist
layer;
exposing the positive photoresist layer to the exposure
source through a photolithography mask wherein the
photolithography mask has thereon an island pattern of a
transmitting material of a percentage transmission;
developing the positive photoresist layer using a negative
tone developer to remove unexposed portions of the positive
photoresist layer and form a hole pattern in the positive
photoresist layer;
etching the semiconductor substrate through the hole
pattern in the positive photoresist layer to form a hole pattern in
the semiconductor substrate; and
removing the positive photoresist layer having the hole
pattern.
Appeal Br. 17 (emphasis added).
The claims on appeal stand rejected as follows:
(1) Claims 1-19 and 21under35 U.S.C. § 112, first paragraph, as
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Application 12/701, 104
failing to comply with the written description requirement;
(2) claims 1-19 and 21under35 U.S.C. § 112, second paragraph,
as indefinite;
(3) claims 1, 4--7, 13, 15-18, and 21under35 U.S.C. § 102(b) as
anticipated by Nyhus;3
(4) claims 2, 8-10, 14, and 19 under 35 U.S.C. § 103(a) as being
unpatentable over Nyhus;
(5) claim 3 under 35 U.S.C. § 103(a) as being unpatentable over
the combination of Nyhus in view of Levinson;4 and
(6) claim 11 under 35 U.S.C. § 103(a) as being unpatentable over
the combination of Nyhus in view of Sheedy. 5
OPINION
As an initial matter, we address the rejection of claims 1-19 and 21
under 35 U.S.C. § 112, second paragraph, as indefinite. The dispositive
issue on appeal is whether Appellants have shown reversible error in the
Examiner's conclusion that claim 1 is indefinite because the limitations
"positive photoresist" and "remove unexposed portions of the positive
photoresist layer" contradict one another. Final Act. 4.
Appellants argue one of ordinary skill in the art would understand that
developing a positive photoresist with a negative tone developer would
remove unexposed portions of the positive photoresist. Appeal Br. 11 and
3 Nyhus et al., US 2004/0101764 Al, published May 27, 2004 ("Nyhus").
4 Levinson et al., US 2009/0239155 Al, published Sept. 24, 2009
("Levinson").
5 Sheedy et al., US 2009/0315644 Al, published Dec. 24, 2009 ("Sheedy").
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Reply Br. 9. To support this argument, Appellants cite Shaw. 6 Appeal Br.
11 and Reply Br. 10. Shaw discloses:
the term "positive photoresist" refers to a photoresist material
that that [sic] when exposed to light (typically UV light) becomes
insoluble to a negative tone developer, while the portion of the
photoresist that is nonexposed (or exposed less) becomes soluble
to the negative tone developer.
Shaw i-f 11.
Shaw may provide a special definition for forming a positive
photoresist layer and using a negative tone developer to remove unexposed
portions of the positive photoresist layer. However, Shaw is not part of, or
otherwise incorporated into, Appellants' Specification. Therefore, we tum
to Appellants' Specification to determine whether Appellants have defined
the use of a positive photoresist layer and a negative tone developer.
During prosecution before the Examiner, the claim language should
be given its broadest reasonable meaning of the words in their ordinary
usage as they \vould be understood by one of ordinary skill in the art, taking
into account any definitions or enlightenment contained in the written
description of Appellants' Specification. See In re Morris, 127 F.3d 1048,
1054 (Fed. Cir. 1997). An inventor may choose to be his own lexicographer
if he defines the specific terms used to describe the invention "with
reasonable clarity, deliberateness, and precision." In re Paulsen, 30 F.3d
1475, 1480 (Fed. Cir. 1994). See Phillips v. AWH Corp., 415 F.3d 1303,
1316 (Fed. Cir. 2005) ("the specification may reveal a special definition
given to a claim term by the patentee that differs from the meaning it would
otherwise possess. In such cases, the inventor's lexicography governs.").
6 Shaw et al. US 2013/0045591 Al, published Feb. 21, 2013 ("Shaw").
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Application 12/701, 104
Appellants contend paragraphs 23, 24, 25, 28, and 29 of the
Specification describe a method in which a positive photoresist layer is
developed by a negative tone developer to remove unexposed portions of the
positive photoresist layer. Appeal Br. 11-13 and Reply Br. 10.
Paragraph 23 of the Specification begins a discussion of the
embodiment depicted in Figure 2. This embodiment involves fabricating
sub-wavelength device features via a single photo exposure, single etch
(lPlE) photolithography process.
Paragraph 24 of the Specification describes an exposure step of the
process, including the patterning of sub-wavelength features via optical
diffraction of light from the exposure source through a phase shift mask.
Paragraph 25 of the Specification describes common types of phase
shift masks, which include alternating phase shift masks and attenuated
phase shift masks (PSMs). Paragraph 25 states (emphasis added):
In alternating PSMs, areas of 0° phase shift and 180° phase
shift may be formed on either sides of a line to be printed on a
wafer coated with a positive photoresist layer . ... By contrast,
in attenuated PSMs, an energy-absorbing, partially-transmitting
film layer may be patterned on a quartz substrate ....
Attenuated PSMs may further be classified based on the pattern
exposed through the energy absorbing layer. For example, on a
dark field attenuated PSM, the background is exposed through
the energy absorbing layer, while on a light field attenuated
PSM, the device features are exposed through the energy
absorbing layer.
Spec. i-f 25 (emphasis added).
Based upon the disclosure of paragraph 25 of the Specification, one of
ordinary skill in the art would have understood that a positive photoresist
layer may be used with at least an alternating phase shift mask. However,
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Application 12/701, 104
paragraphs 26 and 27 of the Specification further define what type of phase
shift mask is used in the embodiment described in paragraphs 23, 24, 25, 28,
and 29. Paragraph 26 refers to the exposure step described in paragraph 24
and states "[t]he high transmission mask of step 201 uses attenuated PSMs
with greater than 6% transmission." The Specification further discloses
attenuated PSMs as providing an improved mask error enhancement factor
and normalized image log slope (NILS), with a light field attenuated phase
shift mask providing greater improvement than a dark field attenuated phase
shift mask. Spec. i-f 26.
Paragraph 27 of the Specification states "[a]n island pattern on a light
field mask is selected because it has been shown that an island pattern on a
light field mask expose[s] device features with enhanced contrast and
improved NILS compared to features exposed through a hole pattern on a
dark field mask." Referring to Figure 3A, paragraph 27 further describes
how areas of a photoresist layer exposed through clear areas of a light field
mask correspond to a background area of a hole pattern while areas of the
photoresist layer that are unexposed, due to the phase shift induced by the
light field mask, correspond to holes of the hole pattern. Therefore,
paragraphs 26 and 27 define the process embodiment of Figure 2 as using an
attenuating phase shift mask, particularly a light field attenuating phase shift
mask. However, paragraphs 23-27 do not define what type of photoresist
(i.e., positive or negative photoresist) can be used in Appellants' process
when an attenuating phase shift mask is used.
Paragraph 28 of the Specification describes a development step in the
process of Figure 2 in which a negative tone developer is used to dissolve
unexposed areas of a photoresist layer. Paragraphs 28 and 29 further
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Application 12/701, 104
describe using a light field mask to expose the photoresist layer. However,
like paragraphs 23-27, paragraphs 28 and 29 do not define whether the
photoresist layer being developed by the negative tone developer is a
positive or negative photoresist layer. As a result, paragraphs 23-29 of the
Specification do not set forth a special definition for forming a positive
photoresist layer and using a negative tone developer to remove unexposed
portions of the positive photoresist layer, as recited in claim 1, with
reasonable clarity, deliberateness, and precision.
"Without evidence in the patent specification of an express intent to
impart a novel meaning to a claim term, the term takes on its ordinary
meaning." Optical Disc Corp. v. Del Mar Avionics, 208 F.3d 1324, 1334
(Fed. Cir. 2000). The Examiner determines the ordinary meaning of a
positive photoresist is a photoresist in which exposed portions of the
photoresist are removed and cites four patent publications as support. Ans.
3--4. One patent publication, for example, discloses:
The photoresist can be in the form of a positive photoresist or a
negative photoresist. The positive photoresist is a photoresist in
which exposed regions are soluble in a developer. In a
corresponding fashion the negative photoresist is a photoresist
in which unexposed regions are soluble in the developer.
Staub et al., US 2008/0310025 Al, published Dec. 18, 2008, i-f 57 (emphasis
added).
Appellants contend the patent publications cited by the Examiner are
not part of a rejection and not relevant as to whether Appellants' application
provides support for claim 1. Reply Br. 9. However, the cited references
are relevant for demonstrating the ordinary meaning of "positive
photoresist" as a photoresist in which exposed regions are removed by a
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Application 12/701, 104
developer and demonstrating the ordinary meaning of "negative photoresist"
as a photoresist in which unexposed regions are removed by a developer.
Claim 1 recites a "positive photoresist layer" but further recites that
"unexposed portions of the positive photoresist layer" are removed via a
negative tone developer. In view of the ordinary meaning of "positive
photoresist" discussed above, the terms "positive photoresist layer" and
"using a negative tone developer to remove unexposed portions of the
positive photoresist layer" contradict one another. As stated by the
Examiner, it is unclear whether claim 1 recites a positive photoresist or a
negative photoresist upon consideration of the ordinary meaning of "positive
photoresist" and "negative photoresist." Ans. 4. Therefore, Appellants'
arguments do not persuade us the Examiner reversibly erred by concluding
claim 1 is indefinite.
The dependent claims do not remedy the indefiniteness issues
discussed above. Moreover, Appellants do not argue independent claims 2-
19 and 21 separately from claim 1. Appeal Br. 9. As a result, for the
reasons discussed above and those set forth in the Examiner's Answer, we
sustain the Examiner's§ 112, second paragraph, rejection of claims 1-19
and 21 as indefinite.
Speculative assumptions would be required to determine the scope of
the claims. In such a situation, it is not appropriate to address the § 112, first
paragraph, rejection for lack of written description because we cannot
determine the meaning of the rejected claim recitations. Further, it is not
appropriate to decide the§§ 102 and 103 rejections. See In re Steele, 305
F.2d 859, 862 (CCPA 1962) (reversed because§ 103 rejection was based on
considerable speculation as to meaning of terms of claims and assumptions
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Application 12/701, 104
as to their scope). Thus, we procedurally reverse the Examiner's rejection
under§ 112, first paragraph, and rejections under§§ 102 and 103. We note
that by procedurally reversing the Examiner's § 112, first paragraph,
rejection and§§ 102 and 103 rejections, we do not reach the merits of these
rejections.
DECISION
The decision of the Examiner is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l).
AFFIRMED
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