Ex Parte Jung

Board of Patent Appeals and Interferences

Sep 19, 2002

09143505 (B.P.A.I. Sep. 19, 2002)

1 Application for patent filed August 28, 1998. Appellant claims the
benefit of priority under 35 U.S.C. § 119 based on Korean Application P97-44218,
filed August 30, 1997. According to Appellant, the real party in interest is LG
Philips LCD Inc. Ltd. (Brief at 1.)
2 Appellant requested a hearing (Paper No. 18, filed July 14, 2000), but
subsequently waived the hearing (Paper No. 21, filed May 16, 2002).
The opinion in support of the decision being entered today:
(1) was not written for publication in a law journal;
and (2) is not binding precedent of the Board.
Paper 22
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte YUN-HO JUNG
____________
Appeal 2001-0107
Application 09/143,5051
____________
ON BRIEF2
____________
Before: GARRIS, PAWLIKOWSKI, and NAGUMO, Administrative Patent
Judges.
NAGUMO, Administrative Patent Judge.
Decision on appeal under 35 U.S.C. § 134
The appeal is from a decision of a primary examiner
rejecting claims 1 through 4, 6 through 14, and 16 through 36,
all the claims remaining in the application. We reverse.
Appeal No. 2001-0107
Application No. 09/143,505
3 To the extent these findings of fact discuss legal issues, they may be
treated as conclusions of law.
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1. Findings of fact
The record supports the following findings by at least a
preponderance of the evidence.3
The invention
The invention relates to a laser annealing system useful for
forming a polycrystalline silicon film from an amorphous silicon
film. (Specification at 1, ll. 5–13.)
According to Appellant, in the prior art, such a system
comprised a vacuum chamber fitted with a quartz chamber window
and a substrate mount. (Id. at 1, l. 23 to 2, l. 8.) The
substrate would be irradiated by a laser beam passing through the
chamber window, which would heat the substrate sufficiently to
cause annealing. (Id. at 3, ll. 2–8.) Appellant discloses that
it is known to pattern the substrate with variously shaped
annealed regions. (Id. at 2, l. 9, to 3, l. 1.) When the
energy density of the laser beam is “excessivly larger than is
necessary for the thickness of the film,” some of the amorphous
film may be vaporized, along with vaporizable contaminants on the
surface of the film. (Id. at ll. 8–12.) Appellant states that
such vaporized contaminants are deposited on the inside of the
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chamber window, which interferes with the laser beam. (Id. at
ll. 13–19.) The laser beam must be repositioned and re-sized,
and the contaminated windows must be cleaned, causing delays and
lowering the process yield. (Id. at ll. 20–29.)
Appellant teaches that the window contamination and
associated problems are overcome in a system in which a “buffer
window” is interposed between the window and the substrate
overcomes. (Id. at 4, ll. 1–9.) Appellant explains that
“[e]ventually, the evaporated contaminants and the partial
components of the film are deposited in the under surface of the
buffer window 34 instead of the chamber window 33. Thus, it is
impossible for the contaminants to reach the chamber window 33
because the buffer window 34 is in the way of the contaminants.”
(Id. at 9, ll. 5–11, referring to Figure 3.) Because the buffer
window and support are entirely within the chamber, there is no
pressure difference across the buffer window, and it may be made
much thinner than the chamber window. (Id. at ll.28–30.) The
buffer window is easily replaced, and is much cheaper than a new
chamber window because it is much thinner. Moreover, the buffer
window may be patterned with a cutoff layer, permitting annealed
patterns to be formed on the substrate upon exposure to the laser
Appeal No. 2001-0107
Application No. 09/143,505
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beam. (Id. at 8, ll.9–18.) Other relevant features of the
invention are readily discerned from the claims.
The claims
The following claims are representative:
1. An annealing system for annealing a target
material with a radiation source, the annealing system
comprising:
a window for passing the radiation source
therethrough;
a process region aligned with the window and
disposed in a path of the radiation source to receive
the radiation source, the process region containing the
target material being annealed; and
a buffer layer aligned with the window and the
process chamber and formed in the path of the radiation
source, wherein the annealing produces a byproduct
containing contaminants, and the buffer layer formed
between the window and the process region substantially
blocks the byproduct from reaching the window.
7. An annealing system of claim 1, wherein the buffer
layer is made of quartz.
8. An annealing system of claim 1, wherein the buffer
layer is mounted on a support frame placed between the
window and the target material to block the byproduct
from reaching the window.
9. An annealing system of claim 1, wherein the buffer
layer has an anti-reflective layer.
34. The annealing system of claim 1, wherein the
byproduct includes vaporized contaminants and wherein
the buffer means substantially prevents the vaporized
contaminants from being deposited on the window.
Appeal No. 2001-0107
Application No. 09/143,505
4 U.S. Patent No. 5,869,803, issued to Takashi Noguchi et al. on
February 9, 1999, which is a continuation of an application filed November 1,
1994.
5 U.S. Patent 5,322,538, issued to Nobuhiro Kondo and Hirokazu Ono on
June 21, 1994.
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The examiner’s rejections
Claims 1–4, 6–14, and 16–36 are rejected as obvious under 35
U.S.C. § 103(a) over the combined teachings of Noguchi4 and
Kondo5.
Noguchi
Noguchi teaches an surface-treatment apparatus that provides
for, inter alia, laser annealing of silicon substrates using a
single shot of laser light. (Noguchi at col. 2, l. 66 to col. 3,
l. 4.) Noguchi describes a system similar to that claimed by
Appellant, except that Noguchi’s system lacks an element that
corresponds to Appellant’s “buffer layer.” More specifically,
with reference to Figure 3, Noguchi describes a chamber 15 having
a window 41 through which the laser light 21 passes on its way to
striking a workpiece 91. (Id. at col. 9, ll. 17–34.) The window
41 may be made of quartz. (Id. at ll. 34–35.) The chamber is
provided with means to provide various atmospheres for the
workpiece, including a vacuum. (Id. at ll. 54–58.) Moreover,
Noguchi teaches that the workpiece may be patterned by placing a
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reticle in the optical path external to the workpiece chamber.
(Id. at col. 10, ll. 12–26.) As for lasers, Noguchi teaches that
excimer lasers, including xenon chloride lasers, are suitable.
(Id. at col. 8, ll. 4–7.) According to Noguchi, a principal
object of the invention is to treat a large area, greater than
about 10 cm2 by a single shot. (Id. at col. 3, ll. 2–4, and
14–17.) Single-shot annealing of 6×6 cm2 areas are reported,
e.g., in Example 1. (Id. at col. 19, ll. 30–40.)
Kondo
Kondo relates to a process of patterning photosensitive
glass by patterned exposure to light followed by etching. More
particularly, Kondo teaches a method that facilitates control
over the etch depth, minimization of surface roughness, and,
particularly for single-sided etching, a way to eliminate the
need to attach protective tape to one side of the photosensitive
glass. (Kondo at col. 2, ll. 5–22.) With reference to Figure 1,
Kondo teaches that a photosensitive glass 10 is exposed to laser
light through an exposure mask 2, which is patterned with shaded
areas 2b that block the laser light from the glass surface.
(Kondo at col. 4, ll. 34–45.) After further laser exposure to
define layer depths (id. at l. 61 to col. 5, l. 6), the glass is
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heated to form crystallized regions in the exposed areas (id. at
col. 5, ll. 19–24), which are subsequently etched away in
hydrofluoric acid (id. at ll. 25–32). A single sided etching
process is illustrated in Figures 12–14, and described in
Embodiment 4, at columns 7–9.
The examiner’s rationale
The examiner maintains, in essence, that Noguchi teaches
every limitation of claim 1 but for the placement of a buffer
layer between the amorphous silica target and the quartz window.
(Examiner’s Answer at 3–4.) To remedy this deficiency, the
examiner relies on Kondo, which, the examiner urges, teaches the
use of an exposure mask in “similar arrangements and methods of
annealing photosensitive glass (which crystallizes in response to
laser radiation)”. (Id. at 4, ll. 1–4, citing Kondo, col. 4,
ll. 30–60, and Figure 1.) The examiner explains that it would
have been obvious to place the exposure mask taught by Kondo
directly above the target in Noguchi because Kondo teaches that
“it would have facilitated differential exposure of a
photosensitive glass to laser radiation.” (Examiner’s Answer
at 4, ll. 4–8.) The examiner argues that positioning the
exposure mask and the necessary mounting means directly above the
target would necessarily shield the chamber window from any
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material ejected from the target. (Id. at ll. 9–13.) Thus, the
subject matter of claims 1, 8, and 34 would have been obvious.
Although the examiner concedes that neither Noguchi nor
Kondo teaches that the exposure mask could be made from quartz,
the examiner notes that the Noguchi apparatus already contains a
quartz chamber window. The examiner concludes that the known
properties (durability, transparency, stability) would have
rendered the use of quartz (as required by claim 7) obvious.
(Id. at ll. 14–19.)
As for the antireflective layer required by claim 9, which
the examiner concedes is not taught by Noguchi or Kondo, the
examiner maintains that it would have been obvious to provide
such a coating on the window to minimize “reflected laser
radiation trapped between the exposure mask and the treated glass
or reflecting from the inside chamber surfaces.” Such reflected
radiation, the examiner asserts, would have “compromised the
precision of the exposure pattern on the glass.” (Examiner’s
Answer at 5, ll. 2–5.)
Appellant’s argument
Appellant does not dispute that Noguchi discloses every
limitation of the claimed invention but for the presence of a
buffer layer (and the associated properties). (Brief at 7.) Nor
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does Appellant dispute that Kondo teaches the use of an exposure
mask in the exposure of a photosensitive glass. (Id. at 7–8.)
Appellant maintains, however, that Kondo does not disclose any of
the limitations required by the claims. (Id. at 8.) Appellant
urges that the examiner has failed to show any teaching or
motivation in these references as to where or how to position
Kondo’s mask in relation to Noguchi’s substrate, or how such a
combination would operate. (Id. at 9.) Moreover, Appellant
urges that Noguchi teaches a scanning system, and that therefore
the mask need not cover the entire substrate, but could be
relatively small, demonstrating the failure of the examiner’s
reliance on inherency. (Brief at 11.)
Appellant also argues that the examiner’s theory of
inherency is flawed because there is no showing that the claimed
system would necessarily substantially block annealing byproducts
from reaching the chamber window. (Id. at 9–10.) Specifically,
Appellant urges that the examiner has assumed incorrectly that
the byproducts travel in a straight line, whereas vaporized
byproducts need not do so. (Id. at 10.) Therefore, argues
Appellant, “merely placing a mask somewhere ‘directly above’ a
[sic] amorphous silicon surface would not inherently - block such
contaminants from reaching the window.” (Id., emphasis original)
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Indeed, Appellant argues that “it is clear that vaporized gaseous
byproducts could — and indeed would — travel by random motion
from the surface of the work product around the exposure mask and
condense on the chamber window.” (Reply Brief at 5.)
In view of our disposition of this appeal, we need not dwell
on Appellant’s arguments with respect to the dependent claims,
save to observe that the Appellant urges that the examiner has
failed to support the rejections with teachings or suggestions in
the prior art.
2. Discussion
In any rejection for obviousness over prior art references,
the burden is on the examiner to demonstrate that the prior art
references teach, expressly or inherently, every limitation of
the claimed subject matter; and, when references must be
combined, that there is a reason, suggestion, teaching, or
motivation arising out of the references, such that one of
ordinary skill in the art would have combined them in such a way
as to arrive at the claimed invention. In re Vaeck, 947 F.2d
488, 493, 20 USPQ2d 1438, 1442 (Fed. Cir. 1991). Moreover,
findings of fact must be supported by substantial evidence in the
record. In re Lee, 277 F.3d 1338, 1344–45, 61 USPQ2d 1430, 1435
(Fed. Cir. 2002) (“The Board’s findings must extend to all
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material facts and must be documented on the record, lest the
‘haze of so-called expertise’ acquire insulation from
accountability. ‘Common knowledge and common sense,’ even if
assumed to derive from the agency’s expertise, do not substitute
for authority when the law requires authority.”)(citations
omitted).
In the present case, we agree with the examiner that Noguchi
discloses a system that meets every limitation of claim 1, but
for the presence of the buffer layer and the functional
properties required of the buffer layer. Kondo, however, stands
on a different footing. As we have described Kondo, supra, we
find that Kondo does not teach laser-induced crystallization of
an amorphous substrate: rather the crystallization results from
a subsequent thermal heating of the substrate. Thus, for the
purposes of the rejection on appeal, we find that the only
relevant teaching of Kondo that is that a mask may be used in
conjunction with a light source in order to expose a substrate to
a desired pattern of radiation. Moreover, we note that the
examiner has failed to direct our attention to any details or
teachings in Kondo regarding the size or placement of the mask
relative to the substrate. Nor has the examiner indicated where
Kondo discloses placing the substrate inside a chamber. Hence,
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Kondo is silent as to the disposition of the exposure mask
relative to such a chamber. In sum, there is no teaching in
Kondo that we may rely on to support a suggestion of where to
position the exposure mask in the system disclosed by Noguchi.
As for Noguchi, we have observed supra that Noguchi does
teach the use of a reticle as part of the optical delivery system
to expose the substrate to a pattern of light. The examiner has
directed our attention to no teaching in Noguchi, however, that a
reticle or exposure mask may be advantageously positioned inside
the sample chamber. The examiner has not established any other
facts in the record in support of placing an exposure mask inside
the sample chamber provided by Noguchi. Accordingly, we are
constrained to reverse the rejection for lack of an adequate
evidentiary basis for the proposed modification.
It seems to us that when a reference provides a way of
achieving a certain result, but mentions no other, then, to
establish that one of ordinary skill in the art would have
recognized that some other way might also be used, a proper
rejection must cite some teaching in the prior art in support of
that other way. Appeal to “common knowledge” of a property of a
material or of the behavior of a system may establish the
“reasonableness” of a proposed modification: but proof of
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obviousness requires more than proof of reasonableness. Most
inventions are, after all, reasonable. The additional
requirement is substantial evidence that the modification and its
reasonableness would have been recognized. The record developed
by the examiner is inadequate because it lacks substantial
evidence supporting positioning an exposure mask between the
chamber window and the substrate. The incidental character of
Kondo’s disclosures regarding masks leaves a vacuum that the
examiner’s attempts to fill by reference to common knowledge or
common sense cannot fill.
Further considerations
In the event of further prosecution, we recommend that the
examiner and Appellant consider the following issues.
a. What is the scope of the term “substantially block the
byproduct from reaching the window”? This term is present in
claim 1, but absent from independent claims 19 and 29, and all
claims dependent on the latter two but for claims 35 and 36,
which were added after the final rejection. (See Paper No. 13.)
The term was introduced to independent claim 1, apparently from
original dependent claim 5, in the amendment responding to the
first office action on the merits. (See Paper No. 5, filed May
27, 1999, at 1–2.) There is no limiting condition in the claims
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that gives a clear meaning to this term; nor is there a clear
definition in the specification. Relative terms are not per se
indefinite, provided there is some reasonable measure of their
scope. See Seattle Box Co. v. Indus. Crating & Packing, Inc.,
731 F.2d 818, 826, 221 USPQ 568, 574 (Fed. Cir. 1984) (a term of
degree is definite if the specification “provides some standard
for measuring that degree. . . . that is, whether one of ordinary
skill in the art would understand what is claimed when the claim
is read in light of the specification.”). Appellant has
discussed the extent of blocking obtained by the claimed
invention (specification at 9; cited by Appellant in Paper No. 5
at 3), but it is not clear whether the discussion was directed to
the scope of all of the claims, or whether that construction was
limited to the merely particular embodiments within the scope of
claim 1. This issue, which is not before us for review, should
be addressed in the first instance by the examiner and Appellant
in view of the extensive considerations of facts and context
required for its resolution.
b. While the present posture of the case does not require
that we address the merits of the arguments with respect to the
dependent claims, we observe that the examiner has not supported
the rejections for obviousness of claimed subject matter
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containing the additional limitations with citations to prior art
reference in the record. In the event the examiner determines
that rejections over additional prior art are warranted, we
emphasize that references must be cited in support of all
findings of fact. While appeal to common knowledge or common
sense may support the reasoning for a rejection for obviousness,
such appeals fail to establish the factual basis on which a
rejection must be based.
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Application No. 09/143,505
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3. Decision
Upon consideration of the appeal, and solely for the reasons
given, The rejection is reversed.
REVERSED.
)
BRADLEY R. GARRIS )
Administrative Patent Judge )
)
)
)
BEVERLY A. PAWLIKOWSKI ) BOARD OF PATENT
Administrative Patent Judge ) APPEALS AND
) INTERFERENCES
)
)
MARK NAGUMO )
Administrative Patent Judge )
Appeal No. 2001-0107
Application No. 09/143,505
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