STC.UNM v. Intel Corporation

Filing 176

DECLARATION re 175 Response in Opposition to Motion,, of Brian L. Ferrall in Support of Intel's Opposition to STC's Motion to Strike and Dismiss Intel's Invalidity Affirmative Defense and Counterclaim by Intel Corporation (Attachments: # 1 Exhibit A, # 2 Exhibit B, # 3 Exhibit C, # 4 Exhibit D, # 5 Exhibit E, # 6 Exhibit F, # 7 Exhibit G, # 8 Exhibit H, # 9 Exhibit I, # 10 Exhibit J, # 11 Exhibit K - part 1, # 12 Exhibit K - part 2, # 13 Exhibit L)(Atkinson, Clifford)

Exhibit 4
STC.UNM v. Intel
Invalidity Claim Chart Comparing '998 Patent to Bae '625
The following asserted claims of STC.UNM’s U.S. Pat. No. 6,042,998 are invalidated pursuant to 35 U.S.C. § 102 and/or § 103, alone or in combination with other
references, by the prior art reference U.S. Pat. No. 5,741,625 to Bae et al., entitled “Process for Forming Fine Patterns in a Semiconductor Device Utilizing Multiple
Photosensitive Film Patterns and Organic Metal-Coupled Material,” filed June 6, 1996 and issued Apr. 21, 1998 (“Bae '625”). These preliminary invalidity contentions
are based on information currently known to Intel, and, as a result, apply interpretations apparently or potentially adopted by STC.UNM. Intel reserves the right to
amend its preliminary invalidity contentions in light of developments in the case such as production of discovery, identification of additional prior art, and issuance of an
order following any Claim Construction Hearing, as stated in the Scheduling Order (Dkt. 47, dated March 2, 2011).

Asserted Claims of '998 Patent
6. A method for obtaining a pattern wherein the Fourier
transform of said pattern contains high spatial frequencies
by combining nonlinear functions of intensity of at least
two exposures combined with at least one nonlinear
processing step intermediate between the two exposures to
form three dimensional patterns comprising the steps of:

Bae '625
See, e.g., Abstract:
“There are disclosed processes for forming fine patterns on a semiconductor substrate to a lesser
degree than the resolving power of a step and repeat used, thereby improving the degree of
integration of the semiconductor device. The process comprises the steps of: forming a first lightexposure mask and a second light-exposure mask with interlaced patterns selected from a plurality
of fine patterns to be formed on a semiconductor substrate; coating an organic material layer on the
semiconductor substrate; patterning the organic material layer by use of the first light-exposure
mask, to form organic material layer patterns; forming a photosensitive film over the organic
material layer patterns; and patterning the photosensitive film by use of the second light-exposure
mask to form photosensitive film patterns, in such a way that each of photosensitive film patterns is
interposed between two adjacent organic material layer patterns.”
See, e.g., figs.6A-6F:

EXHIBIT D
Ex. 4: Page 1

Asserted Claims of '998 Patent

Bae '625

Ex. 4: Page 2

Asserted Claims of '998 Patent

Bae '625

Ex. 4: Page 3

Asserted Claims of '998 Patent

Bae '625

See, e.g., C8:54 to C10:11:
“Turning now to FIGS. 6A through 6F, there is illustrated a step process for forming fine patterns
on a semiconductor device, according to a fourth embodiment of the present invention.
First, a beam of light is irradiated, as indicated by arrows, through a first light-exposure mask 98
into a semiconductor device comprising a semiconductor substrate 88 on which a polysilicon layer
90, a first photosensitive film 92, an intermediate layer 94 and a second photosensitive film 96 are
sequentially formed. As a result, the second photosensitive film 96 is selectively exposed to the
light and thus divided into non-exposed areas and exposed areas. While the intermediate film 94 is
prepared by coating SOG on the first photosensitive film 92, the first and the second photosensitive
films 92, 96 are formed by coating a positive photosensitive solution on the polysilicon layer 90
and the intermediate layer 94 in a spin-coat and spray manner. The SOG layer 94 consists of glass
materials, such as phospho silicate glass, boro phospho silicate glass, and undoped silicate glass.
With regard to the first light-exposure mask 98, it comprises a quartz substrate 100 transmissive to
light on which first photointerceptive film patterns 102 are formed of chrome.
In accordance with the present invention, the first photointerceptive film patterns 102 are twice as
sparse as object photosensitive film patterns to be formed. For example, if the object photosensitive

Ex. 4: Page 4

Asserted Claims of '998 Patent

Bae '625
film patterns have 0.4 .mu.m of unit pitch consisting of 0.2 .mu.m of the width of a pattern and 0.2
.mu.m of the distance between two adjacent patterns, the first photointerceptive film patterns 102
have 0.8 .mu.m of unit pitch consisting of the same width of the pattern and 0.6 .mu.m of the
distance between two adjacent patterns.
The exposed areas of the second photosensitive film 96 are taken off, to form second
photosensitive film patterns 96A through which the SOG layer 94 is selectively exposed, as shown
in FIG. 6B. Then, a reactive ion etching process is carried out to remove the SOG layer 94 exposed
selectively by the second photosensitive film patterns 96A, at half of its total thickness, so as to
form first SOG layer patterns 94A. Each of the first SOG layer patterns 94A is positioned between
the residual SOG layers 94 and the second photosensitive film patterns 96A.
Thereafter, the second photosensitive film patterns 96A atop the first SOG layer patterns 94A are
eliminated, and over the resulting structure, there is newly formed a third photosensitive film 104,
as shown in FIG. 6C. A beam of light is irradiated, as indicated by arrow, through a second lightexposure mask 106 into the third photosensitive film 104 which thus is divided into exposed areas
and non-exposed areas.
With regard to the second light-exposure mask 160, it is comprised of a quartz substrate 108 and
second photointerceptive film patterns 110 atop the quartz substrate 108. The second
photointerceptive film patterns 110 in the second light-exposure mask 106 are alternated with the
first photointerceptive film patterns 102 in the first light-exposure mask so as not to overlap the
formed with the latter. That is, the second photointerceptive film patterns 110 with, for example,
0.8 .mu.m of unit pitch consisting of 0.2 .mu.m of pattern width and 0.6 .mu.m of the distance
betweeen two adjacent patterns, and the first photointerceptive film patterns 102 having the same
dimensions are positioned alternatively.
As shown in FIG. 6D, the exposed areas of the third photosensitive film 104 are removed to form
third photosensitive film patterns 104A which bare the first SOG layer patterns 94A completely
and expose the residual SOG layer partially therethrough, and then, the first SOG layer patterns
94A and the residual SOG layer 94 are subjected to anisotropic etch in a reactive ion etching
manner, so as to form second SOG layer patterns 94B. That is, the second SOG layer patterns 94B
are formed of the lower portions of the first SOG layer patterns 94A and of the residual SOG layer
94 underneath the third photosensitive film patterns 104A therethrough. These second SOG layer
patterns 94B are fine patterns with, for example, 0.4 .mu.m of unit pitch consisting of 0.2 .mu.m of
pattern width and 0.2 .mu.m of distance between two adjacent patterns.
Subsequently, the third photosensitive film patterns 104A are taken off and the first photosensitive
film exposed selectively through the second SOG layer patterns 92A is also removed, to form first
photosensitive film patterns 92A through which the polysilicon layer 90 is selectively exposed, as

Ex. 4: Page 5

Asserted Claims of '998 Patent

Bae '625
shown in FIG. 6E. After completion of the formation of the first photosensitive film patterns 92A,
the second SOG layer patterns 94B are eliminated.
Finally, the polysilicon layer 90 is removed with the first photosensitive film patterns 92A serving
as a mask, to form fine polysilicon layer patterns 90A, followed by removal of the first
photosensitive film patterns 92A, as shown in FIG. 6F.”
The phrase “the Fourier transform of said pattern contains high spatial frequencies” is an inherent
result of the nonlinear processing step. Also, Admitted Prior Art in the '998 patent itself, Brueck
'835, Waldo '094, Ziger, Gwozdz, and Elliott1 each discloses nonlinear processing, e.g., as
explained in “Invalidity Claim Chart Comparing '998 Patent to AAPA, Brueck '835, Waldo '094,
Ziger, Gwozdz, and Elliott,” served concurrently herewith.

coating a substrate with a first mask material and a first
photoresist layer;

See, e.g., figs.6A-6B:

exposing said first photoresist layer with a first exposure
developing said photoresist to form a first pattern in said
first photoresist layer, said first pattern containing spatial
frequencies greater than those in a two dimensional optical
intensity image imposed onto said photoresist layer in said
first exposure as a result of a nonlinear response of said
first photoresist layer;

1

U.S. Patent No. 5,415,835 to Brueck et al. (“Brueck '835”), U.S. Patent No. 4,891,094 to Waldo III (“Waldo '094”), David H. Ziger, et al., Generalized Approach
Toward Modeling Resist Performance, ALCHE JOURNAL, Vol. 37, No. 12, Dec. 1991, at 1863-74 (“Ziger”), Peter S. Gwozdz, Positive Versus Negative: A Photoresist
Analysis, SEMICONDUCTOR LITHOGRAPHY VI, SPIE Vol. 275, 1981 (“Gwozdz”), and/or David J. Elliott, INTEGRATED CIRCUIT FABRICATION TECHNOLOGY, 2d ed., 1989,
at 85-106 and 326 (“Elliott”).

Ex. 4: Page 6

Asserted Claims of '998 Patent

Bae '625

See, e.g., C8:58 to C9:6:
“First, a beam of light is irradiated, as indicated by arrows, through a first light-exposure mask 98
into a semiconductor device comprising a semiconductor substrate 88 on which a polysilicon layer
90, a first photosensitive film 92, an intermediate layer 94 and a second photosensitive film 96 are
sequentially formed. As a result, the second photosensitive film 96 is selectively exposed to the
light and thus divided into non-exposed areas and exposed areas. While the intermediate film 94 is
prepared by coating SOG on the first photosensitive film 92, the first and the second photosensitive
films 92, 96 are formed by coating a positive photosensitive solution on the polysilicon layer 90
and the intermediate layer 94 in a spin-coat and spray manner. The SOG layer 94 consists of glass
materials, such as phospho silicate glass, boro phospho silicate glass, and undoped silicate glass.”
See, e.g., C9:20-23:
“The exposed areas of the second photosensitive film 96 are taken off, to form second
photosensitive film patterns 96A through which the SOG layer 94 is selectively exposed, as shown
in FIG. 6B.”
The phrase “containing spatial frequencies greater than those in a two dimensional optical intensity
image imposed onto said photoresist layer . . . as a result of a nonlinear response of said
[photoresist layer]” is inherently disclosed in the above-cited disclosure of photoresist. Also,
Admitted Prior Art in the '998 patent itself, Brueck '835, Waldo '094, Ziger, Gwozdz, and Elliott
each discloses the nonlinear response of photoresist, e.g., as explained in “Invalidity Claim Chart
Comparing '998 Patent to AAPA, Brueck '835, Waldo '094, Ziger, Gwozdz, and Elliott,” served
concurrently herewith.

Ex. 4: Page 7

Asserted Claims of '998 Patent
transferring said first pattern into said first mask material,
said first mask material comprising at least one of
SiO.sub.2, Si.sub.3 N.sub.4, a metal, a polysilicon and a
polymer;

Bae '625
See, e.g., fig.6B:

See, e.g., C9:23-26:
“Then, a reactive ion etching process is carried out to remove the SOG layer 94 exposed selectively
by the second photosensitive film patterns 96A, at half of its total thickness, so as to form first SOG
layer patterns 94A.”
coating said substrate with a second photoresist;

See, e.g., figs.6C-6D:

exposing said second photoresist with a second exposure
developing said second photoresist layer to form a second
pattern in said second photoresist layer, said second pattern
containing spatial frequencies greater than those in a two
dimensional optical intensity image imposed onto said
photoresist layer in said second exposure as a result of a
nonlinear response of said second photoresist layer;

Ex. 4: Page 8

Asserted Claims of '998 Patent

Bae '625

See, e.g., C9:30-58:
“Thereafter, the second photosensitive film patterns 96A atop the first SOG layer patterns 94A are
eliminated, and over the resulting structure, there is newly formed a third photosensitive film 104,
as shown in FIG. 6C. A beam of light is irradiated, as indicated by arrow, through a second lightexposure mask 106 into the third photosensitive film 104 which thus is divided into exposed areas
and non-exposed areas.
With regard to the second light-exposure mask 160, it is comprised of a quartz substrate 108 and

Ex. 4: Page 9

Asserted Claims of '998 Patent

Bae '625
second photointerceptive film patterns 110 atop the quartz substrate 108. The second
photointerceptive film patterns 110 in the second light-exposure mask 106 are alternated with the
first photointerceptive film patterns 102 in the first light-exposure mask so as not to overlap the
formed with the latter. That is, the second photointerceptive film patterns 110 with, for example,
0.8 .mu.m of unit pitch consisting of 0.2 .mu.m of pattern width and 0.6 .mu.m of the distance
betweeen two adjacent patterns, and the first photointerceptive film patterns 102 having the same
dimensions are positioned alternatively.
As shown in FIG. 6D, the exposed areas of the third photosensitive film 104 are removed to form
third photosensitive film patterns 104A which bare the first SOG layer patterns 94A completely
and expose the residual SOG layer partially therethrough, and then, the first SOG layer patterns
94A and the residual SOG layer 94 are subjected to anisotropic etch in a reactive ion etching
manner, so as to form second SOG layer patterns 94B.”
The phrase “containing spatial frequencies greater than those in a two dimensional optical intensity
image imposed onto said photoresist layer . . . as a result of a nonlinear response of said
[photoresist layer]” is inherently disclosed in the above-cited disclosure of photoresist. Also,
Admitted Prior Art in the '998 patent itself, Brueck '835, Waldo '094, Ziger, Gwozdz, and Elliott
each discloses the nonlinear response of photoresist, e.g., as explained in “Invalidity Claim Chart
Comparing '998 Patent to AAPA, Brueck '835, Waldo '094, Ziger, Gwozdz, and Elliott,” served
concurrently herewith.

transferring said first pattern and said second pattern into
said substrate using a combined mask including parts of
said first mask layer and said second photoresist;

See, e.g., figs.6D-6F:

Ex. 4: Page 10

Asserted Claims of '998 Patent

Bae '625

See, e.g., C9:50 to C10:11:
“As shown in FIG. 6D, the exposed areas of the third photosensitive film 104 are removed to form
third photosensitive film patterns 104A which bare the first SOG layer patterns 94A completely
and expose the residual SOG layer partially therethrough, and then, the first SOG layer patterns
94A and the residual SOG layer 94 are subjected to anisotropic etch in a reactive ion etching
manner, so as to form second SOG layer patterns 94B. That is, the second SOG layer patterns 94B
are formed of the lower portions of the first SOG layer patterns 94A and of the residual SOG layer
94 underneath the third photosensitive film patterns 104A therethrough. These second SOG layer
patterns 94B are fine patterns with, for example, 0.4 .mu.m of unit pitch consisting of 0.2 .mu.m of
pattern width and 0.2 .mu.m of distance between two adjacent patterns.
Subsequently, the third photosensitive film patterns 104A are taken off and the first photosensitive
film exposed selectively through the second SOG layer patterns 92A is also removed, to form first
photosensitive film patterns 92A through which the polysilicon layer 90 is selectively exposed, as
shown in FIG. 6E. After completion of the formation of the first photosensitive film patterns 92A,
the second SOG layer patterns 94B are eliminated.
Finally, the polysilicon layer 90 is removed with the first photosensitive film patterns 92A serving
as a mask, to form fine polysilicon layer patterns 90A, followed by removal of the first
photosensitive film patterns 92A, as shown in FIG. 6F.”

Ex. 4: Page 11

Asserted Claims of '998 Patent
removing said first mask material and said second
photoresist.

Bae '625
See, e.g., figs.6E-6F:

See, e.g., C9:66 to C10:11:
“Subsequently, the third photosensitive film patterns 104A are taken off and the first photosensitive
film exposed selectively through the second SOG layer patterns 92A is also removed, to form first
photosensitive film patterns 92A through which the polysilicon layer 90 is selectively exposed, as
shown in FIG. 6E. After completion of the formation of the first photosensitive film patterns 92A,
the second SOG layer patterns 94B are eliminated.
Finally, the polysilicon layer 90 is removed with the first photosensitive film patterns 92A serving
as a mask, to form fine polysilicon layer patterns 90A, followed by removal of the first
photosensitive film patterns 92A, as shown in FIG. 6F.”
7. The method of claim 6 wherein said transferring step
includes at least one of etching, deposition and-lift off, and
damascene.

See, e.g., C9:23-26:
“Then, a reactive ion etching process is carried out to remove the SOG layer 94 exposed selectively
by the second photosensitive film patterns 96A, at half of its total thickness, so as to form first SOG
layer patterns 94A.”
See, e.g., C9:50-58:

Ex. 4: Page 12

Asserted Claims of '998 Patent

Bae '625
“As shown in FIG. 6D, the exposed areas of the third photosensitive film 104 are removed to form
third photosensitive film patterns 104A which bare the first SOG layer patterns 94A completely
and expose the residual SOG layer partially therethrough, and then, the first SOG layer patterns
94A and the residual SOG layer 94 are subjected to anisotropic etch in a reactive ion etching
manner, so as to form second SOG layer patterns 94B.”

8. A method for increasing spatial frequency content of
lithographic patterns comprising the steps of:

See, e.g., figs.3C-3F:

Ex. 4: Page 13

Asserted Claims of '998 Patent

Bae '625

See, e.g., C5:26 to C6:5:
“With reference to FIGS. 3C through 3F, there is illustrated a process for forming fine patterns of a
semiconductor device, according to a first embodiment on a the present invention.
First, as shown in FIG. 3C, a light is irradiated, as indicated by arrows, through the first lightexposure mask 23 of FIG. 3A into a semiconductor device comprising a lower layer 34 on which
an organic material layer 36 and a first photosensitive film 38 are sequentially formed. The lower
layer 34 is atop a semiconductor substrate (not shown). As a result, the first photosensitive film 38
is selectively exposed to the beam. In the meantime, the organic material layer 36 serves as a
reflection-protective layer.
Thereafter, the light-exposed areas of the first photosensitive film 38 are removed, to form first
photosensitive film patterns 38A through which the organic material layer 36 is partially exposed,

Ex. 4: Page 14

Asserted Claims of '998 Patent

Bae '625
as shown in FIG. 3D. Then, an etching step is undertaken to take off the organic material layer 36
exposed partially through the first photosensitive film patterns 38A, to form organic material layer
patterns 36A which, in turn, expose the lower layer 34 selectively therethrough.
Following formation of the organic material layer patterns 36A, the first photosensitive film
patterns 38A are eliminated, and a second photosensitive film 40 is coated entirely over the
resulting structure, as shown in FIG. 3E. The second photosensitive film 40 is exposed to a beam of
light irradiated as indicated by arrows. At this time, the second light-exposure mask 28 of FIG. 3B
causes the second photosensitive film 40 to be exposed selectively.
Finally, for formation of a second photosensitive film pattern 40A, all areas of the second
photosensitive film but the masked one are removed so as to bare the organic material layer pattern
40A completely, as shown in FIG. 3F. As mentioned above, the second photointerceptive film
pattern 32 is positioned at the central portion between the first photointerceptive film patterns 26 so
as not to overlap the first photointerceptive film patterns 26 with the second photointerceptive film
pattern 32. Based on this position structure, the second photosensitive film pattern 40A is
interposed between the organic material layer patterns 36A. All of the second photosensitive film
patterns 40A and the organic material layer pattern 36A play a role of a mask for the fine pattern
which exposes the lower layer 34 selectively therethrough.”
See, e.g., figs.6A-6F:

Ex. 4: Page 15

Asserted Claims of '998 Patent

Bae '625

Ex. 4: Page 16

Asserted Claims of '998 Patent

Bae '625

Ex. 4: Page 17

Asserted Claims of '998 Patent

Bae '625

See, e.g., C8:54 to C10:11:
“Turning now to FIGS. 6A through 6F, there is illustrated a step process for forming fine patterns
on a semiconductor device, according to a fourth embodiment of the present invention.
First, a beam of light is irradiated, as indicated by arrows, through a first light-exposure mask 98
into a semiconductor device comprising a semiconductor substrate 88 on which a polysilicon layer
90, a first photosensitive film 92, an intermediate layer 94 and a second photosensitive film 96 are
sequentially formed. As a result, the second photosensitive film 96 is selectively exposed to the
light and thus divided into non-exposed areas and exposed areas. While the intermediate film 94 is
prepared by coating SOG on the first photosensitive film 92, the first and the second photosensitive
films 92, 96 are formed by coating a positive photosensitive solution on the polysilicon layer 90
and the intermediate layer 94 in a spin-coat and spray manner. The SOG layer 94 consists of glass
materials, such as phospho silicate glass, boro phospho silicate glass, and undoped silicate glass.
With regard to the first light-exposure mask 98, it comprises a quartz substrate 100 transmissive to
light on which first photointerceptive film patterns 102 are formed of chrome.
In accordance with the present invention, the first photointerceptive film patterns 102 are twice as
sparse as object photosensitive film patterns to be formed. For example, if the object photosensitive
film patterns have 0.4 .mu.m of unit pitch consisting of 0.2 .mu.m of the width of a pattern and 0.2
.mu.m of the distance between two adjacent patterns, the first photointerceptive film patterns 102

Ex. 4: Page 18

Asserted Claims of '998 Patent

Bae '625
have 0.8 .mu.m of unit pitch consisting of the same width of the pattern and 0.6 .mu.m of the
distance between two adjacent patterns.
The exposed areas of the second photosensitive film 96 are taken off, to form second
photosensitive film patterns 96A through which the SOG layer 94 is selectively exposed, as shown
in FIG. 6B. Then, a reactive ion etching process is carried out to remove the SOG layer 94 exposed
selectively by the second photosensitive film patterns 96A, at half of its total thickness, so as to
form first SOG layer patterns 94A. Each of the first SOG layer patterns 94A is positioned between
the residual SOG layers 94 and the second photosensitive film patterns 96A.
Thereafter, the second photosensitive film patterns 96A atop the first SOG layer patterns 94A are
eliminated, and over the resulting structure, there is newly formed a third photosensitive film 104,
as shown in FIG. 6C. A beam of light is irradiated, as indicated by arrow, through a second lightexposure mask 106 into the third photosensitive film 104 which thus is divided into exposed areas
and non-exposed areas.
With regard to the second light-exposure mask 160, it is comprised of a quartz substrate 108 and
second photointerceptive film patterns 110 atop the quartz substrate 108. The second
photointerceptive film patterns 110 in the second light-exposure mask 106 are alternated with the
first photointerceptive film patterns 102 in the first light-exposure mask so as not to overlap the
formed with the latter. That is, the second photointerceptive film patterns 110 with, for example,
0.8 .mu.m of unit pitch consisting of 0.2 .mu.m of pattern width and 0.6 .mu.m of the distance
betweeen two adjacent patterns, and the first photointerceptive film patterns 102 having the same
dimensions are positioned alternatively.
As shown in FIG. 6D, the exposed areas of the third photosensitive film 104 are removed to form
third photosensitive film patterns 104A which bare the first SOG layer patterns 94A completely
and expose the residual SOG layer partially therethrough, and then, the first SOG layer patterns
94A and the residual SOG layer 94 are subjected to anisotropic etch in a reactive ion etching
manner, so as to form second SOG layer patterns 94B. That is, the second SOG layer patterns 94B
are formed of the lower portions of the first SOG layer patterns 94A and of the residual SOG layer
94 underneath the third photosensitive film patterns 104A therethrough. These second SOG layer
patterns 94B are fine patterns with, for example, 0.4 .mu.m of unit pitch consisting of 0.2 .mu.m of
pattern width and 0.2 .mu.m of distance between two adjacent patterns.
Subsequently, the third photosensitive film patterns 104A are taken off and the first photosensitive
film exposed selectively through the second SOG layer patterns 92A is also removed, to form first
photosensitive film patterns 92A through which the polysilicon layer 90 is selectively exposed, as
shown in FIG. 6E. After completion of the formation of the first photosensitive film patterns 92A,

Ex. 4: Page 19

Asserted Claims of '998 Patent

Bae '625
the second SOG layer patterns 94B are eliminated.
Finally, the polysilicon layer 90 is removed with the first photosensitive film patterns 92A serving
as a mask, to form fine polysilicon layer patterns 90A, followed by removal of the first
photosensitive film patterns 92A, as shown in FIG. 6F.”

depositing a material;

See, e.g., figs.3C-3D:

depositing a photoresist on said material;
exposing a periodic image in said photoresist, said periodic
image having a pitch p.sub.min and a linewidth less than
p.sub.min /2;
developing said periodic image to form a periodic pattern
in said photoresist;

See, e.g., C5:30-44:
“First, as shown in FIG. 3C, a light is irradiated, as indicated by arrows, through the first lightexposure mask 23 of FIG. 3A into a semiconductor device comprising a lower layer 34 on which
an organic material layer 36 and a first photosensitive film 38 are sequentially formed. The lower
layer 34 is atop a semiconductor substrate (not shown). As a result, the first photosensitive film 38
is selectively exposed to the beam. In the meantime, the organic material layer 36 serves as a

Ex. 4: Page 20

Asserted Claims of '998 Patent

Bae '625
reflection-protective layer.
Thereafter, the light-exposed areas of the first photosensitive film 38 are removed, to form first
photosensitive film patterns 38A through which the organic material layer 36 is partially exposed,
as shown in FIG. 3D.”
See, e.g., figs.6A-6B:

Ex. 4: Page 21

Asserted Claims of '998 Patent

Bae '625
See, e.g., C8:58 to C9:23:
“First, a beam of light is irradiated, as indicated by arrows, through a first light-exposure mask 98
into a semiconductor device comprising a semiconductor substrate 88 on which a polysilicon layer
90, a first photosensitive film 92, an intermediate layer 94 and a second photosensitive film 96 are
sequentially formed. As a result, the second photosensitive film 96 is selectively exposed to the
light and thus divided into non-exposed areas and exposed areas. While the intermediate film 94 is
prepared by coating SOG on the first photosensitive film 92, the first and the second photosensitive
films 92, 96 are formed by coating a positive photosensitive solution on the polysilicon layer 90
and the intermediate layer 94 in a spin-coat and spray manner. The SOG layer 94 consists of glass
materials, such as phospho silicate glass, boro phospho silicate glass, and undoped silicate glass.
With regard to the first light-exposure mask 98, it comprises a quartz substrate 100 transmissive to
light on which first photointerceptive film patterns 102 are formed of chrome.
In accordance with the present invention, the first photointerceptive film patterns 102 are twice as
sparse as object photosensitive film patterns to be formed. For example, if the object photosensitive
film patterns have 0.4 .mu.m of unit pitch consisting of 0.2 .mu.m of the width of a pattern and 0.2
.mu.m of the distance between two adjacent patterns, the first photointerceptive film patterns 102
have 0.8 .mu.m of unit pitch consisting of the same width of the pattern and 0.6 .mu.m of the
distance between two adjacent patterns.
The exposed areas of the second photosensitive film 96 are taken off, to form second
photosensitive film patterns 96A through which the SOG layer 94 is selectively exposed, as shown
in FIG. 6B.”

transferring said periodic pattern to said material;

See, e.g., fig.3D:

See, e.g., C5:44-49:

Ex. 4: Page 22

Asserted Claims of '998 Patent

Bae '625
“Then, an etching step is undertaken to take off the organic material layer 36 exposed partially
through the first photosensitive film patterns 38A, to form organic material layer patterns 36A
which, in turn, expose the lower layer 34 selectively therethrough.”
See, e.g., fig.6B:

See, e.g., C9:23-26:
“Then, a reactive ion etching process is carried out to remove the SOG layer 94 exposed selectively
by the second photosensitive film patterns 96A, at half of its total thickness, so as to form first SOG
layer patterns 94A.”
depositing a second photoresist layer on said material;

See, e.g., figs.3E-3F:

offsetting said periodic pattern by p.sub.min /2;
repeating said exposing, developing and transferring steps,
thereby interpolating new said pattern midway between
said pattern.

Ex. 4: Page 23

Asserted Claims of '998 Patent

Bae '625

See, e.g., C5:50 to C6:5:
“Following formation of the organic material layer patterns 36A, the first photosensitive film
patterns 38A are eliminated, and a second photosensitive film 40 is coated entirely over the
resulting structure, as shown in FIG. 3E. The second photosensitive film 40 is exposed to a beam of
light irradiated as indicated by arrows. At this time, the second light-exposure mask 28 of FIG. 3B
causes the second photosensitive film 40 to be exposed selectively.
Finally, for formation of a second photosensitive film pattern 40A, all areas of the second
photosensitive film but the masked one are removed so as to bare the organic material layer pattern
40A completely, as shown in FIG. 3F. As mentioned above, the second photointerceptive film
pattern 32 is positioned at the central portion between the first photointerceptive film patterns 26 so
as not to overlap the first photointerceptive film patterns 26 with the second photointerceptive film
pattern 32. Based on this position structure, the second photosensitive film pattern 40A is

Ex. 4: Page 24

Asserted Claims of '998 Patent

Bae '625
interposed between the organic material layer patterns 36A. All of the second photosensitive film
patterns 40A and the organic material layer pattern 36A play a role of a mask for the fine pattern
which exposes the lower layer 34 selectively therethrough.”
See, e.g., figs.6C-6F:

Ex. 4: Page 25

Asserted Claims of '998 Patent

Bae '625

See, e.g., C9:30 to C10:11:
“Thereafter, the second photosensitive film patterns 96A atop the first SOG layer patterns 94A are
eliminated, and over the resulting structure, there is newly formed a third photosensitive film 104,
as shown in FIG. 6C. A beam of light is irradiated, as indicated by arrow, through a second lightexposure mask 106 into the third photosensitive film 104 which thus is divided into exposed areas
and non-exposed areas.
With regard to the second light-exposure mask 160, it is comprised of a quartz substrate 108 and
second photointerceptive film patterns 110 atop the quartz substrate 108. The second
photointerceptive film patterns 110 in the second light-exposure mask 106 are alternated with the
first photointerceptive film patterns 102 in the first light-exposure mask so as not to overlap the
formed with the latter. That is, the second photointerceptive film patterns 110 with, for example,
0.8 .mu.m of unit pitch consisting of 0.2 .mu.m of pattern width and 0.6 .mu.m of the distance
betweeen two adjacent patterns, and the first photointerceptive film patterns 102 having the same
dimensions are positioned alternatively.
As shown in FIG. 6D, the exposed areas of the third photosensitive film 104 are removed to form
third photosensitive film patterns 104A which bare the first SOG layer patterns 94A completely
and expose the residual SOG layer partially therethrough, and then, the first SOG layer patterns
94A and the residual SOG layer 94 are subjected to anisotropic etch in a reactive ion etching
manner, so as to form second SOG layer patterns 94B. That is, the second SOG layer patterns 94B

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Asserted Claims of '998 Patent

Bae '625
are formed of the lower portions of the first SOG layer patterns 94A and of the residual SOG layer
94 underneath the third photosensitive film patterns 104A therethrough. These second SOG layer
patterns 94B are fine patterns with, for example, 0.4 .mu.m of unit pitch consisting of 0.2 .mu.m of
pattern width and 0.2 .mu.m of distance between two adjacent patterns.
Subsequently, the third photosensitive film patterns 104A are taken off and the first photosensitive
film exposed selectively through the second SOG layer patterns 92A is also removed, to form first
photosensitive film patterns 92A through which the polysilicon layer 90 is selectively exposed, as
shown in FIG. 6E. After completion of the formation of the first photosensitive film patterns 92A,
the second SOG layer patterns 94B are eliminated.
Finally, the polysilicon layer 90 is removed with the first photosensitive film patterns 92A serving
as a mask, to form fine polysilicon layer patterns 90A, followed by removal of the first
photosensitive film patterns 92A, as shown in FIG. 6F.”

9. The method of claim 8, wherein said step of depositing a
material includes depositing doped polysilicon.

See, e.g., C8:58-63:
“First, a beam of light is irradiated, as indicated by arrows, through a first light-exposure mask 98
into a semiconductor device comprising a semiconductor substrate 88 on which a polysilicon layer
90, a first photosensitive film 92, an intermediate layer 94 and a second photosensitive film 96 are
sequentially formed.”

10. The method of claim 8, wherein said material includes
an SiO.sub.2 overlayer configured to act as a hardmask
during said etching step.

See, e.g., C8:65 to C9:6:

11. The method of claim 8, wherein said step of depositing
a photoresist includes depositing at least one of a negative
photoresist, a positive photoresist and a positive
photoresist with an image reversal step.

See, e.g., C10:12-17:

16. The method of claim 8, wherein said step of
developing said periodic pattern includes etching said

“While the intermediate film 94 is prepared by coating SOG on the first photosensitive film 92, the
first and the second photosensitive films 92, 96 are formed by coating a positive photosensitive
solution on the polysilicon layer 90 and the intermediate layer 94 in a spin-coat and spray manner.
The SOG layer 94 consists of glass materials, such as phospho silicate glass, boro phospho silicate
glass, and undoped silicate glass.”

“Though a positive photosensitive film is exemplified in the fourth embodiment of the present
invention, properly controlled positive/negative photosensitive solutions for the first and the second
photosensitive films along with light-exposure masks appropriate for these solutions may also be
useful to form fine patterns.”
See, e.g., C2:44-56:

Ex. 4: Page 27

Asserted Claims of '998 Patent
pattern into a hardmask.

Bae '625
“In order to overstep the limit of the fine pattern formed by the process of FIG. 1, there has been
suggested a multilayer photosensitive film process in which a plurality of light-exposure steps are
executed repeatedly. That is, a phase-reverse masking process in which the phase of a beam is
reversed, is used to reduce an exposure effect caused by interference of another beam of light
passing through an adjacent pattern, and a top surface imaging (hereinafter referred to as "TSI")
process which comprises a plasma etching step wherein a relatively hard top layer coupled with an
organic metal material is formed partially over the surface of photosensitive film, is utilized to form
photosensitive film patterns.”
See, e.g., C3:22-42:
“Then, the photosensitive film 14 is contacted with an organic metal material gas containing silicon
and permeated therewith, to form a silylation layer 22 consisting of silicon. At the moment, the
silylation layer formed on the light-exposed area of the photosensitive film 14 is thicker than that
formed on the non-exposed area of the photosensitive film 14 due to differences in diffusion rate
and reaction rate with silicon between the exposed area and the non-exposed area. In addition, in
the silylation layer 22 formed on the exposed area of the photosensitive film 14, a central portion is
thicker than any other portion, and as the distance from the central portion is farther, the thickness
of the silylation layer is thinner. Further, the silylation layer 22 has a hard structure more resistant
to plasma than that of the photosensitive film 14.
Subsequently, the areas of the photosensitive film 14 without silicon ale removed by means of
oxygen plasm to a degree that the object material layer of etch 12 is selectively exposed with the
silylation layer 22 serving as a mask. Thus, photosensitive film patterns are formed.”

18. The method of claim 8, wherein said step of depositing
a material includes depositing a material on at least one of
a textured substrate, a quantum structure, a flux pinning
site for high-T.sub.c superconductors, a birefringent
material, a reflective optical coating, a photonic bandgap,
an electronic device, an optical storage media, a magnetic
storage media, an array of field emitters and a Dynamic
Random Access Memory capacitor.

See, e.g., C5:30-40:
“First, as shown in FIG. 3C, a light is irradiated, as indicated by arrows, through the first lightexposure mask 23 of FIG. 3A into a semiconductor device comprising a lower layer 34 on which
an organic material layer 36 and a first photosensitive film 38 are sequentially formed. The lower
layer 34 is atop a semiconductor substrate (not shown). As a result, the first photosensitive film 38
is selectively exposed to the beam. In the meantime, the organic material layer 36 serves as a
reflection-protective layer.”

20336-1313/LEGAL20544215.1

Ex. 4: Page 28