Ex Parte Sandhu

Board of Patent Appeals and Interferences

Jan 30, 2004

08336260 (B.P.A.I. Jan. 30, 2004)

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The opinion in support of the decision being
entered today is not binding precedent of the Board.
Paper 105
Filed by: Interference Trial Section Merits Panel
Mail Stop Interference Filed:
P.O. Box 1450 30 January 2004
Alexandria, VA 22313-1450
Tel: 703-308-9797
Fax: 703-305-0942
UNITED STATES PATENT AND TRADEMARK OFFICE
_______________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_______________
CISSY LEUNG and KARL A. LITTAU,
Junior Party,
(Application 09/128,143),
v.
GURTEJ S. SANDHU,
Senior Party,
(Patent 5,576,071).
_______________
Patent Interference No. 104,661
_______________
Before: SCHAFER, SPIEGEL and TIERNEY, Administrative Patent Judges.
SCHAFER, Administrative Patent Judges.
DECISION ON PRELIMINARY MOTIONS AND FINAL JUDGMENT
INTRODUCTION
The following preliminary motions are before us for consideration:
1. Sandhu Preliminary Motion 2 (Paper 69) seeking a judgment that all of Leung’s
involved claims are unpatentable under 35 U.S.C. § 112, first paragraph, as not being supported by
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a written description or an enabling disclosure. We grant this motion with respect to written
description and deny it with respect to enabling disclosure.
2. Sandhu Preliminary Motion 3 (Paper 70) attacking the benefit dates accorded
Leung in the Notice declaring interference. We dismiss this motion as moot.
3. Sandhu Preliminary Motion 4 (Paper 71) seeking to undesignate certain Sandhu
claims. We also dismiss this motion as moot.
4. Leung Preliminary Motion 1 (Paper 74) to substitute a different count. We also
dismiss this motion as moot.
5. Leung Preliminary Motion 2 (Paper 75) to amend Leung claim 13. We also
dismiss this motion as moot.
Leung’s involved claims were added to Leung’s involved application to provoke this
interference. Those claims formed the sole basis for declaring this interference with Sandhu’s
claims. We hold that Leung’s claims are not supported by the original specification of Leung’s
involved application and introduced new matter. Since none of Leung’s involved claims are
supported by a written description, under the particular circumstances of this case, Leung lacks
standing to prosecute this interference. None of the other preliminary motions, whether or not
granted, would affect Leung’s standing and thus are moot. It is, therefore, appropriate to enter final
judgment against Leung.
FINDINGS OF FACT
The following findings are supported by a preponderance of the evidence. Additional
findings may be present in the Analysis section of this opinion.
Background
The Parties
F 1. This interference is between Leung Application 09/128,143 (the 143 Application) and
Sandhu Patent 5,576,071.
F 2. The real party in interest of the Leung application is Applied Materials, Inc. of Santa Clara,
California. Paper 13.
F 3. The real party in interest of the Sandhu patent is Micron Technology, Inc. of Boise, Idaho.
Paper 5, assignment recorded at Reel 007227, Frame 0009.
1 The 143 Application was itself refiled as a “continued prosecution application” or CPA. Except for
entitling an applicant to a new set of Office actions, the CPA application is treated for all purposes as if it were the
“parent” application. The CPA maintains the same serial number as the parent application. CPA papers are placed in
the parent file wrapper and the papers are numbered beginning with the next number after the last paper number in the
parent. Amendments entered in the parent application remain entered in the CPA. No new matter may be entered into
the CPA. Subject matter that would be new matter in the parent will also be new matter in the CPA. And subject matter
added to the parent that is new matter is new matter in the CPA. 37 CFR § 1.53(d) and MPEP § 201.06(d). For the
purpose of this decision, we have treated the CPA and its “parent” as a single application and refer to them collectively
as the 143 Application and the specification as the 143 Specification.
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Relevant Prosecution Histories
The 143 Application
F 4. Leung’s involved Application 09/128,143 is the fourth in a chain of applications.1
F 5. The three earlier applications (referred to collectively as “the parent applications”) are
08/969,377 (the parent application); 08/498,990 (the grandparent application) and
08/339,521 (the great-grandparent application).
F 6. The text of the original 143 Specification, as filed, is admitted, in a transmittal letter
submitted with the filing of the 143 Application, to be identical to the text of the great-
grandparent application, as filed:
The specification of this continuation application is identical to (i.e., a true
copy of) the 08/339,521 [(great-grandparent)] application.
Application 09/128,143, transmittal letter filed 3 August 1998, bracketing added.
F 7. A comparison of the text of the 143 Specification, as filed, appears to be identical to the text
of the great-grandparent specification, as filed.
F 8. Both the transmittal letter and a preliminary amendment filed concurrently with the 143
Application attempt to incorporate the disclosures of the parent applications. Application
09/128,143, transmittal letter filed 3 August 1998; Application 09/128,143, Paper 4.
F 9. However, Leung, in a paper filed during this interference, has specifically disclaimed reliance
upon any additional subject matter present in the parent and grandparent applications to
support the involved claims:
[T]he “new matter” contained in the [parent and grandparent] applications that
makes the [143] application a C-I-P with respect to the [great-grandparent]
application is not used in anyway to support the claims of the [143]
application.
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Paper 104, p. 15.
F 10. When the 143 Application was filed it was characterized by Leung as a “continuation.”
Application 09/128,143, Paper 5, Attachment, p. 1.
F 11. A patent examiner objected to this characterization, asserting that the 143 Application was
a continuation-in-part:
Applicant[s’] have incorrectly called this application a continuation of
08/969,377, because the specification is NOT a true copy of that application’s
specification. Consequently, appropriate papers to indicate that this
application is a CIP of the previous application is needed.
Application 09/128,143, Paper 6, p. 2.
F 12. After further prosecution, Leung filed an amendment designating the 143 Application to be
a continuation-in-part, “to expedite prosecution.” Paper 15, p. 2.
F 13. Thus, the 143 Application is currently characterized as a “continuation-in-part.” of the parent
application. Application 09/128,143, Paper 15, p. 2.
F 14. The parent application is said to be a continuation of the grandparent application. Application
08/969,377, Paper 15, p. 1.
F 15. The grandparent application is said to be a continuation-in-part of the great-grandparent
application. Application 08/969,377, Paper 15, p. 2.
F 16. As originally filed, the 143 Specification included 12 claims. Application 09/128,143,
Specification, pp. 18-19.
F 17. A preliminary amendment cancelled all claims and added Claims 13-28 and requested an
interference with the Sandhu patent. Application 09/128,143, Paper 4, pp. 1-5.
F 18. In the preliminary amendment, Leung noted that Leung Claims 13 and 20, the only
independent claims, were “substantially copied Sandhu claims 27 and 28.” Application
09/128,143, Paper 4, p. 6.
The Sandhu Patent
F 19. The Sandhu patent issued from Application 08/336,260 filed 8 November 1994. Patent
5,576,071, p. 1, col. 1.
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The Interference
The Order of the Parties
F 20. The Notice Declaring Interference accorded Leung the benefit of the filing dates of the Leung
parent, grandparent, and great grandparent applications giving Leung an effective
constructive reduction to practice date of 14 November 1994. Paper 1, p. 3.
F 21. Sandhu’s constructive reduction to practice date is the 8 November 1994 filing date of
Application 08/336,260, which issued as Sandhu’s involved patent. Patent 5,576,071, p. 1,
col. 1.
F 22. Since Sandhu had the earliest date of a constructive reduction to practice, Sandhu was
designated the senior party.
Subject Matter of the Interference
F 23. The subject matter of this interference relates to methods of decreasing the resistivity and the
amount of carbon present in thin films deposited on semiconductor wafers by chemical vapor
deposition (CVD).
F 24. The film may be a material such a titanium nitride (TiN).
F 25. The methods include placing the wafers in a reactor chamber and filling the chamber with a
vapor of an organic compound –a “precursor compound”– under conditions which will
deposit the desired film onto the wafer.
F 26. For a TiN film the organic compound may be tetrakisdialkylamido titanium (Ti(NR2)4, where
R stands for the “alkyl” moiety).
F 27. The wafer with deposited layer is then subject to a post-treatment to reduce resistivity and the
amount of carbon in the layer .
F 28. The film deposition and post-treatment steps are then repeated.
F 29. Leung’s claims specify post treating
with hydrogen gas and generating a plasma to reduce the carbon content of
said layer and thereby decrease the resistivity of the layer.
Paper 11, pp. 1-5.
F 30. Leung’s Claim 19, which is dependent upon Claim 13, is representative of the interfering
subject matter as claimed by Leung (emphasis and indentation added):
Leung 13.
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A method of minimizing the carbon content in a layer of material atop a wafer
by chemical vapor deposition using an organometallic compound,
the method comprising the following steps:
positioning said wafer in a chemical vapor deposition reactor;
injecting said organometallic compound into said reactor
having said wafer positioned therein
at a temperature and pressure
to deposit on said wafer a layer of
metal nitride
containing significant
a mo u n t s o f
carbon
to adversely affect the
resistivity of
said layer; and
after depositing said layer, post-treating said wafer in said reactor
with hydrogen gas and generating plasma
to reduce the carbon content of said layer and
thereby decrease the resistivity of said
layer.
Paper 11, pp. 1-2.
Leung 19.
The method of claim 13 wherein
both said step of depositing on said wafer a layer of metal nitride, and
said step of post-treating said wafer,
are repeated.
Paper 11, p. 3.
F 31. In Sandhu’s claims, the post-treatment step is
injecting hydrogen gas into the reactor and generating a first reactive
hydrogen plasma within the reactor against the first layer, the hydrogen
effectively diffusing into the first layer and reacting with hydrocarbons in the
first layer to produce gaseous products which diffuse outwardly of the first
layer and are expelled from the reactor.
Paper 7, p. 3-10.
F 32. Sandhu’s Claim 2, which is dependent upon Claim 1, is representative of the interfering
subject matter as claimed by Sandhu (emphasis and indentation added):
Sandhu 1.
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A method of minimizing hydrocarbon incorporation in a layer of material
provided atop a wafer by chemical vapor deposition using an organic
precursor,
the method comprising the following steps:
positioning a wafer within a chemical vapor deposition reactor;
injecting an organic precursor within the reactor having the wafer
positioned therein, and
maintaining the reactor
at a temperature and
a pressure
which in combination are effective to deposit a first layer of
material onto the wafer
which incorporates carbon from the organic precursor
in the form of hydrocarbons;
after depositing the first layer,
ceasing to inject the organic precursor into the reactor and
first injecting hydrogen gas into the reactor and
generating a first reactive hydrogen plasma within the reactor
against the first layer,
the hydrogen effectively diffusing into the first layer
and
reacting with hydrocarbons in the first layer
to produce gaseous products
which diffuse outwardly of the first
layer and
are expelled from the reactor;
after the first reactive hydrogen plasma treatment,
injecting the organic precursor and carrier gas within the
reactor, and
maintaining the reactor at a
temperature and
a pressure
which in combination are effective to deposit a second
layer of the material onto the wafer
which incorporates carbon from the organic
precursor; and
after depositing the second layer,
ceasing to inject the organic precursor into the reactor and
second injecting hydrogen gas into the reactor and
generating a second reactive hydrogen plasma within the
reactor against the second layer,
the hydrogen effectively diffusing into the second
layer and
reacting with carbon in the second layer
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to produce gaseous products
which diffuse outwardly of the second
layer and
are expelled from the reactor.
Paper 7, pp. 3-4.
Sandhu 2.
The chemical vapor deposition method of claim 1
wherein the organic precursor is an organometallic precursor.
Paper 7, p. 4.
F 33. The count is as follows:
Count 1
Claim 19 of Leung Application 09/128,143 or Claim 2 of Sandhu Patent 5,576,071.
Paper 1, p. 5.
The Involved Claims
F 34. The claims of the parties are:
Leung 13-28
Sandhu 1-28
Paper 1, p. 5.
F 35. The claims of the parties which correspond to Count 1 are:
Leung 13, 19, 20, 26
Sandhu 1, 2, 12, 13, 27, 28
Paper 1, p. 5.
F 36. The claims of the parties which do not correspond to Count 1, and therefore are not involved
in the interference, are:
Leung 14-18, 21-25, 27, 28
Sandhu 3-11, 14-26
Paper 1, p. 5.
2 Sandhu’s comments were specifically made with respect to the specification of the great grandparent
application, Application 08/339,521. However, the comments are equally applicable to the specification of the 143
Application since the text of the great grandparent specification appears to be and is said to be identical to the text of
the 143 Specification. See F6 and F7, above. We need not consider the content of the parent and grandparent
applications since Leung has disclaimed reliance on whatever additional description is present in those applications.
Paper 104, p. 15.
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Sandhu Preliminary Motion 2
Sandhu’s Position
F 37. Sandhu has filed a preliminary motion asserting that all of Leung’s involved claims, Claims
13, 19, 20 and 26, are unpatentable under 35 U.S.C. § 112, ¶ 1. Paper 69.
F 38. Sandhu asserts that each of Leung’s involved claims are unpatentable because Leung’s
written description “fails to provide an enabling disclosure or written description of the
claimed subject matter.” Paper 69, p. 2.
F 39. In particular, Sandhu argues that each of the involved claims require a post treatment with a
hydrogen plasma which must reduce (1) the carbon content and (2) the resistivity of the
deposited layer. Paper 69, p. 4.
F 40. Sandhu argues that the 143 Specification2 does not provide a written description of reducing
carbon content and decreasing resistivity without a post-treatment including biasing the
substrate:
The [143 Application] does not teach any method to “reduce the carbon
content” and “decrease the resistivity” of any layer deposited by chemical
vapor deposition without including the biasing of the substrate. This biasing
step is understood from the Leung . . . application by those of skill in the art
(see Vasilyeva Affidavit ¶ 15-16) to be required and essential to reduce carbon
content and decrease resistivity by the . . . specification, but is not included as
part of the limitations of Leung claims 13, 19, 20, or 26. As stated in
the. . . specification, the invention is “a post treatment of films formed via
chemical vapor deposition by exposure of the deposited film to an inert
plasma while biasing the substrate. This is the only process described by the
. . . specification that accounts for any improvement of a film by possibly
lowering carbon content and decreasing resistivity.
Paper 69, pp. 9-10 (bracketed material added, footnote omitted, underlining and italics
original).
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F 41. Sandhu argues that Leung’s involved claims do not require biasing the substrate and the
specification neither describes nor enables a process which reduces carbon and resistivity
which does not also bias the substrate. Paper 69, p. 8.
F 42. In Sandhu’s view, the 143 Specification describes biasing the substrate as a required, essential
or necessary part of Leung’s inventive contribution and that claims which do not include
biasing are neither enabled nor supported by a written description. Paper 69, pp. 9-11, 14-16
and 23.
F 43. For example, Sandhu argues that
the <143 application provides no support for the Leung claim limitations, and
in fact reinforces the requirement of using a “power treatment” with the
plasma to bias the substrate, a feature not included in the claims.
Paper 69, p. 15, emphasis original.
F 44. Sandhu also notes that the involved claims were added to the 143 Application by a
preliminary amendment which is not part of the original 143 Specification as filed and can
not be relied upon to avoid the introduction of new matter. Paper 69, p. 4.
F 45. Sandhu relies on specific portions of the specification and the declaration testimony of Irina
Vasilyeva (submitted as Sandhu Exhibit 1015) to support both the lack of written description
and the enablement arguments. Paper 69, p. 4.
The Vasilyeva Affidavit
F 46. Vasilyeva testifies that based upon her background she is knowledgeable as to what a person
of ordinary skill in the art would know relating to semiconductor processing. SX 1015,
pp. 5-6, ¶ 5.
F 47. Vasilyeva testifies that from the period 14 November 1994 to the present controlling the
composition and resistivity of deposited films was “highly unpredictable.” SX 1015, p. 7,
¶ 10.
F 48. Vasilyeva specifically testifies:
10. During the period from November 14, 1994, to the present, the field of
semiconductor processing science, especially as it relates to the practice of
chemical reactions used in semiconductor manufacturing processes to obtain
specific results such as controlling the elemental composition of deposited
films, or controlling the resistivity of such films, has been a highly
unpredictable science, and is understood as such by those of ordinary skill in
3 Vasilyeva’s testimony was expressly addressed to the specification of the great-grandparent
application. However, since the original specifications of the great-grandparent and the 143 Application appear to be
and are admitted to be identical, we have construed the testimony as applying to the 143 Application as well. See F6
and F7, above. We need not refer to the parent and grandparent applications since Leung has disclaimed reliance on
whatever additional description is present in those applications. Paper 104, p. 15.
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the art. Indeed, this is underscored by the following statement made by Leung
in the <143 application at page 8, lines 6-8 (Exhibit 1002), that they did not
understand how their invention worked: “[a]lthough the exact mechanism of
the present invention is not known, we believe the high energy ion
bombardment of the films on a biased substrate densifies the films.”
SX 1015, p. 7, ¶ 10.
F 49. Vasilyeva testifies that she reviewed the 143 Specification3 “to determine if the disclosure
therein was sufficient to enable one skilled in the art to make and use the invention defined
in Leung claims 13, 19, 20 and 26.”
F 50. Based upon this review, Vasilyeva expresses the opinion that one skilled in the art would not
have been able to make and use the subject matter of Leung claims 13, 19, 20 and 26. SX
1015, pp. 7-8, ¶ 11.
F 51. Vasilyeva also testifies that the 143 Specification does not teach any method to reduce
carbon content and decrease resistivity without voltage biasing the substrate and that biasing
is understood to be a required step to reduce the carbon content and resistivity. SX 1015, pp.
10-11, ¶¶ 15-17.
F 52. Vasilyeva summarizes her testimony stating that in order for one of ordinary skill to have
practiced the claimed invention based on the disclosures of 143 Application, an extraordinary
amount of experimentation would have been required. SX 1015, p. 15, ¶ 24.
Leung’s Opposition
F 53. Leung opposes arguing (1) that Sandhu has not met its burden of proof in not alleging
sufficient material facts in support of the motion; (2) that the Vasilyeva affidavit does not
establish experience and knowledge in the field of chemical vapor deposition and is therefore
not competent to be relied upon as expert testimony; and (3) that Sandhu has not established
by a preponderance of the evidence that the 143 Specification fails to enable the Leung
claims. Paper 85, pp. 5-6.
4 Dr. Chang’s testimony was specifically directed to the specification of the great-grandparent
application. However, since the original specification of the great-grandparent is admitted to be and appears to be
identical to the original specification of the 143 Application (See F6 and F7, above), we have considered Dr. Chang’s
testimony to be equally applicable to the 143 Specification. We need not refer to any additional content that may be
present in the parent and grandparent applications since Leung has disclaimed reliance on whatever additional description
is present in those applications. Paper 104, p. 15.
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F 54. Leung additionally argues that Leung’s involved claims are supported by a written description
because they are supported by the specifications of the parent, grandparent, and great
grandparent applications which are said to be incorporated by reference into the 143
Specification. Paper 85, pp. 19-22.
F 55. However, Leung, in a subsequently filed paper, has specifically disclaimed reliance upon the
additional subject matter present in the parent and grandparent applications to support the
involved claims:
[T]he “new matter” contained in the [parent and grandparent] applications that
makes the [143] application a C-I-P with respect to the [great-grandparent]
application is not used in anyway to support the claims of the [143]
application.
Paper 104, p. 15.
F 56. Leung also admits that the preliminary amendment submitted with the filing of the 143
Application is not part of the original disclosure of the 143 Application. Paper 104, p. 5.
F 57. With respect to the new matter argument Leung argues that the preliminary amendment did
not add any information not already supported by the parent, grandparent, and great
grandparent applications. Paper 85, p. 19.
F 58. Leung’s opposition (Paper 85) does not address the issue that biasing the substrate is taught
by the 143 Specification to be a necessary or essential part of the Leung invention.
The Chang Declaration
F 59. Leung relies on the testimony of Dr. Mei Chang (LX 2021).
F 60. Dr. Chang testifies:4
11. In one aspect the . . . specification teaches, the use of a hydrogen
plasma to reduce the carbon content and the resistivity of a metal nitride layer
deposited using chemical vapor deposition (CVD) through decomposition of
an organometallic precursor, which is a limitation of Leung claims 13, 19, 20
and 26. Specifically, on page 8, lines 18-21, the . . . specification states that
“the precursor gas used to form the plasma for the post-deposition treatment
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step described herein can be any gas, but is preferably a
non-oxygen-and-carbon-containing gas, such as nitrogen, ammonia, argon,
and the like”. Hydrogen gas is a non-oxygen-and-carbon-containing gas. It is
well known in the art, and was well known in the art at the time of the Leung
. . . specification, that a plasma of ammonia gas contains a plasma of hydrogen
gas. Additionally, on page, 11 in Table II, the . . . specification details
resistivity measurements obtained for a metal nitride sample film C5 pre- and
post-deposition plasma treated using a hydrogen (H2) plasma. At page 11,
lines 6-10, the metal nitride sample film C5 was plasma treated “using a low
power of 100 watts and without biasing the substrate”. Table II is a
continuation of Table I shown on page 10 of the . . . specification. In Table I,
the Control film has a resistivity of 16,000 microohmscentimeter (:S-cm). In
Table II, C5 has a resistivity of 13,500 :S-cm, which is approximately a 15
% decrease in resistivity as compared to the Control film (see calculation 1).
16 000 13 500
16 000
100% 15%, ,
,
−⎛
⎝⎜
⎞
⎠⎟
× =
Given the . . . specification’s recitation on page 8, lines 16-19 that plasma
treated metal nitride films are “more crystalline, contain more nitrogen, and
have reduced oxygen and carbon content” as compared to untreated metal
nitride films, and the 15 % decrease in resistivity for the metal nitride sample
film C5 plasma treated using a power of 100 watts and without substrate
biasing, one of ordinary skill in the art would be able to practice a method of
post-treating a metal nitride layer with a hydrogen gas plasma to reduce the
carbon concentration and decrease the resistivity of such layer, as required by
Leung claims 13, 19, 20 and 26.
LX 2021, pp. 4-6, ¶ 11.
The 143 Specification
Content of the Written Description
F 61. The 143 Specification notes that prior art CVD deposition of TiN using tetrakisdialkylamido
titanium results in resistivity that is too high and is unstable:
[T]he resistivity of the titanium nitride film is high and unstable. Over time
the resistivity increases to such an extent that the film is no longer usable for
semiconductor devices.
Application 09/128,143, Specification, p. 2. l. 23 - p. 3, l. 1.
5 We note that conventional unit of resistivity is ohms-cm and that a normal unit of sheet resistance or
resistivity is ohms/sq. or ohms/Q. The 143 Specification sometimes specifies resistivity as :ohms-cm/sq (e.g.,
Application 09/128,143, Specification, p. 7, ll. 4-19), other times as :ohms-cm (e.g., Application 09/128,143,
Specification, p. 10, Table I and p. 11, Table II) and still others as :ohms/sq (Application 09/128,143, Figure 2.). The
143 Specification appears to use these designations interchangeably and we have also considered them to be
interchangeable for the purpose of this opinion.
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F 62. The 143 Specification says that resistivities of the order of 10,000 :ohms-cm/sq5 and above
are unacceptable for TiN barrier layer materials:
After exposure to air, the sheet resistivity of these titanium nitride films can
increase to values of about 10,000 up to about 100,000 :ohms-cm/sq, which
is highly undesirable when using the film as a barrier layer for conductive
contacts and vias.
Application 09/128,143, Specification, p. 7, ll. 13-17.
F 63. The 143 Specification notes that for barrier layer films stable sheet resistivities preferably
should be on the order 1000 :ohms-cm/sq:
For that application, stable sheet resistivities on the order of about 1000
:ohms-cm/sq or less are desired.
Application 09/128,143, Specification, p. 7, ll.17-19.
F 64. The 143 Specification reports the resistivity and stability of a number of CVD TiN “control”
films, said to have been made using prior art CVD parameters. Application 09/128,143,
Specification, p. 9, l. 5 - p. 10, l. 2; p. 10, ll. 15-19; p. 12, l. 15.
F 65. These TiN films were reported as having resistivities between about 11,000 and 16,000
:ohms-cm. Application 09/128,143, Specification, p. 9, ll. 21-22; p. 10, l. 19, p. 12, l. 15.
F 66. One set of “prior art” TiN films were said to have unacceptably high average resistivity of
11,360 :ohms-cm/sq which significantly increased on exposure to air. Application
09/128,143, Specification, p. 9, l. 5 - p. 10, l. 2 and Fig. 2.
F 67. These “prior art” films was said to show an unacceptably high level of carbon and oxygen.
Application 09/128,143, Specification, p. 10, ll. 3-11 and Fig. 3.
F 68. Another “prior art” film was said to be made according to the same prior art process as the
film referred to in F61, above was reported as having a resistivity of 16,000 :ohm-cm.
Application 09/128,143, Specification, p. 10, ll. 15-16 and Table 1.
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F 69. The 143 Specification reports the properties of another “prior art” film –Control B– as having
a resistivity of 11,020 which increased by 130% in twenty-four hours. Application
09/128,143, Specification, p. 12, ll. 2-10 and Table III, Control.
F 70. The 143 Specification attributes instability of the resistivity to undesirable amounts of carbon
which causes the resistivity to degrade when exposed to the atmosphere:
The titanium nitride obtained contains significant amounts of carbon, and the
resultant titanium nitride films are chemically reactive. Thus when the films
are exposed to air or other oxygen containing gas, oxygen is absorbed and the
films then contain both carbon and oxygen as impurities. Since the oxygen
absorption is uncontrolled, the stability of the films is impaired, which
adversely affects the resistivity of the film in particular, in addition to possibly
impairing the reliability of devices made from the films.
Application 09/128,143, Specification, p. 7, ll. 4-13.
F 71. The 143 Specification also describes some additional unsuccessful processes (Examples C1-
C4) attempting to improve the properties of TiN CVD films. Application 09/128,143,
Specification, p. 3, ll. 2-15; p. 10, ll. 12-24.
F 72. Some of these processes were said to introduce additional gases during the CVD step.
Application 09/128,143, Specification, p. 10, ll. 12-16.
F 73. The results are summarized in Table 1. Application 09/128,143, Specification, p. 10.
F 74. Only Example C2, deposited in the presence of NF3, showed decreased resistivity compared
to the control sample. Application 09/128,143, Specification, p. 10, Table 1, Example C2.
F 75. However, Example C2 was said to be unacceptable because of high fluorine content.
Application 09/128,143, Specification, p. 10, l. 28 - p. 11, l. 3.
F 76. The other examples (C1, C3 and C4) were reported has having resistivities significantly
higher than the unacceptable resistivity of 16,000 :ohm-cm reported for the “prior art”
control. Application 09/128,143, Specification, p. 10, Table 1, Example C1, C3 and C4.
F 77. The 143 Specification also describes three additional CVD processes said to have used pre-
and post-treatments in attempting to lower resistivity. Application 09/128,143, Specification,
p. 11, ll. 4-20.
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F 78. In two of the processes (Examples C5 and C6), the substrate was said to be exposed to
hydrogen and nitrogen plasmas, respectively, both before and after CVD deposition of TiN.
Application 09/128,143, Specification, p. 11, Table II, Examples C5 and C6.
F 79. The 143 Specification specifically notes that in making the films of Examples C5 and C6 the
substrate was not biased:
a plasma was initiated before and after chemical vapor deposition of titanium
nitride using a low power of 100 watts and without biasing the substrate
silicon wafer.
Application 09/128,143, Specification, p. 11, ll. 6-9 (emphasis added).
F 80. The films of Examples C5 and C6 were said to have resistivities of 13,500 and 15,500
:ohms-cm. Application 09/128,143, Specification, p. 11, Table II.
F 81. The effect of the plasma treatment on the carbon content of the films of Examples C5 and C6
is not described in the 143 Specification.
F 82. The effect of the plasma treatment on the stability of the resistivity of the films of Examples
C5 and C6 is not described in the 143 Specification.
F 83. A third process (Example C7) was said to include post-treating the CVD film with NF3.
Application 09/128,143, Specification, p. 11, Table II, Example C7.
F 84. Example C7 was reported as having a resistivity of 16,500 :ohms-cm. Application
09/128,143, Specification, p. 11, Table II, Example C7.
F 85. The 143 Specification characterizes the pre- and post-treatments of Examples C5, C6 and C7
as having little effect on resistivity:
It is apparent that none of these pre- and post-treatments had much effect on
the sheet resistivity.
Application 09/128,143, Specification, p. 11, ll. 19-20.
F 86. The 143 Specification emphasizes that a technique for reducing resistivity and improving
stability of TiN films is desired:
Thus a method of treating a titanium nitride film deposited by chemical vapor
deposition that will modify the film to reduce its resistivity and improve its
stability is highly desirable.
Application 09/128,143, Specification, p. 3, ll. 16-19.
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F 87. The stated purpose of the invention described by the 143 Specification is to modify CVD
films to reduce resistivity and improve stability. Application 09/128,143, Specification, p.
3, ll. 16-19.
F 88. In the section titled “Summary of the Invention,” the 143 Specification states that the
inventors have found that post treating films with an inert plasma while biasing the substrate
will improve film resistivity and stability:
We have found that a post treatment of films formed via chemical vapor
deposition by exposure of the deposited film to an inert plasma while biasing
the substrate, results in more stable films. In particular, titanium nitride films
formed by chemical vapor deposition from a metallo-organo titanium
compound are modified to improve the resistivity and stability of the films.
Application 09/128,143, Specification, p. 3, l. 20 - p. 4, l. 2 (emphasis added).
F 89. The 143 Specification says that subjecting a CVD TiN film to an inert plasma containing
“high energy ions, obtained by applying a DC bias voltage to the substrate” is “[i]n
accordance to the process of the present invention:”
In accordance with the process of the present invention, films of titanium
nitride are post treated with an inert plasma containing high energy ions,
obtained by applying a DC bias voltage to the substrate. Only a low power RF
level need be applied, i.e., sufficient power to form a plasma from a precursor
gas, and a voltage of about 100 to 1000 volts applied to the substrate. For
example, a voltage of about 400 volts while applying only 100 watts of RF
power to form a plasma is quite sufficient to produce high energy ions and to
passivate or densify a titanium nitride film so that it remains stable over time.
Application 09/128,143, Specification, p. 7, l. 20 - p. 8, l. 5 (emphasis added).
F 90. The written description further emphasizes the importance of applying a voltage bias during
the plasma treatment:
Thus, it was highly unexpected that when a bias voltage was applied to the
substrate in a plasma, the sheet resistivity markedly decreased, and, more
importantly, remained stable over time.
Application 09/128,143, Specification, p. 11, ll. 21-24.
F 91. The use of high energy ions is said not to adversely effect coverage, deposition rate or barrier
performance, but
does markedly reduce the absorption of oxygen by the film and stabilizes the
resistivity of the titanium nitride film.
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Application 09/128,143, Specification, p. 8, l. 23 - p. 9, l. 4.
F 92. In stating that the invention should not be limited to expressly disclosed details, the
143 Specification notes only that the invention should not be limited to TiN and that other
materials may benefit from the use of a bias voltage during the plasma treatment:
The present invention is not meant to be limited to titanium nitride barrier
layers and the post deposition bias voltage in a plasma treatment of the
invention can serve to improve properties and chemical composition of other
materials as well . . . .
Application 09/128,143, Specification, p. 15, ll. 13-17 (emphasis added).
F 93. The 143 Specification includes a comparison of the resistivity of a control sample made
according to the prior art CVD process with the resistivities of eight examples post-treated
with a plasma and a bias voltage. Application 09/128,143, Specification, p. 12, ll. 1-32.
F 94. The control sample was said to have an initial resistivity of 11,020 :ohms-cm which
increased by 130% in 24 hours. Application 09/128,143, Specification, p.12, Table III,
Control.
F 95. Examples 1-8, each plasma post-treated with nitrogen while applying a bias of 400 volts,
were reported as having significantly lower resistivities and significantly lower resistivity
change over 24 hours. Application 09/128,143, Specification, p. 12, Table III, Examples 1-8.
F 96. These bias-treated films which are said to have resistivities ranging from 913 to 4,620 and
increases in resistivity of 2 to 43% over 24 hours. Application 09/128,143, Specification, p.
12, Table III, Examples 1-8.
F 97. Apparently based upon the Examples 1-8 in Table III, the 143 Specification states the
following conclusion:
Thus titanium nitride resistivity can be markedly reduced and stability
dramatically improved, e.g., a 2% increase in resistivity over 24 hours, by a
post treatment of titanium nitride films applying a bias voltage to the substrate
in a nitrogen or other plasma.
Application 09/128,143, Specification, p. 12, l. 32 - p. 13, l. 1 (emphasis added).
F 98. These TiN films “of the invention” are stated to have a low, stable sheet resistivity.
Application 09/128,143, Specification, p. 8, ll. 16-17.
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F 99. The 143 Specification notes that when films which have been subjected to a plasma and
bombarded with high energy ions are exposed to air, water vapor or oxygen
the oxygen is not absorbed, or is absorbed to a much lesser extent than when
no bias voltage has been applied.
Application 09/128,143, Specification, p. 8, ll. 4-19.
F 100. The 143 Specification also notes that “the treated titanium films of the invention” are more
crystalline, contain more nitrogen and have reduced amounts of oxygen and carbon when
compared to the prior art films. Application 09/128,143, Specification, p. 8, ll. 11-16.
F 101. The 143 Specification indicates that the improved properties of the films results from
densification due to high energy ion bombardment:
Although the exact mechanism of the present invention is not known, we
believe the high energy ion bombardment of the films on a biased substrate
densifies the films.
Application 09/128,143, Specification, p. 8, ll. 6-8 (emphasis added).
F 102. The 143 Specification expresses the view that the densification of the film by bombardment
with high energy ions from the biased plasma results in reduced oxygen absorption:
We believe that biasing the substrate in the plasma bombards the surface with
high energy ions that densify the film, and in turn reduce the absorption of
oxygen by the film after exposure to atmosphere.
Application 09/128,143, Specification, p. 4, l. 2-6 (emphasis added).
F 103. The 143 Specification reports the results of Rutherford back scattering spectrum (RBS)
density testing of Examples 7, 8 and the control. Application 09/128,143, Specification, p.
15, ll. 3-9.
F 104. The densities of Examples 7 and 8 were reported to be higher than the density of the control.
Application 09/128,143, Specification, p. 15, Table IV.
F 105. The 143 Specification then concludes:
Thus plasma treatment and bombardment with high energy ions increased the
density of titanium nitride films as compared to the Control.
Application 09/128,143, Specification, p. 15, ll. 10-12 (emphasis added.).
F 106. The 143 Specification also reports the results of Auger analysis of the atomic concentration
of the elements vs. sputter depth etch of the TiN layer said to have been made in Examples
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1, 7, and 8 which were post-treated in a biased plasma. Application 09/128,143, Specification,
p. 13, l. 2 - p. 14, l. 15.
F 107. The Auger analysis of the bias-treated examples is said to show the “change in elemental
composition of the films after treatment in accordance with the invention.” Application
09/128,143, Specification, p. 13, ll. 13-15 (emphasis added).
F 108. The Auger analysis was said to show the presence of both oxygen and carbon but that the
oxygen content was markedly reduced. Application 09/128,143, Specification, p. 14, l. 3 -
p. 14, l. 10.
F 109. However, the Auger analysis is also said to show that carbon content of voltage bias-treated
films did not change:
Carbon is the only other major impurity, and remains unaffected by the
present process.
Application 09/128,143, Specification, p. 14, ll. 10-12.
Original Claims
F 110. As filed, the 143 Application included 12 claims. Application 09/128,143, Specification, pp.
18-19.
F 111. Claims 1, 2 and 9 were the only independent claims. Application 09/128,143, Specification,
pp. 18-19.
F 112. Each of the original claims required either bombarding the film with high energy ions or
exposing a film to a plasma while applying a bias voltage. Application 09/128,143,
Specification, pp. 18-19.
F 113. Leung Claim 1 was directed to the method of improving the properties of the film deposited
on a substrate by “bombarding the films with energetic ions.” Application 09/128,143,
Specification, p. 18, ll. 1-3.
F 114. Leung Claim 2 required “exposing the film to a plasma of a precursor gas while applying a
bias voltage to said substrate.” Application 09/128,143, Specification, p. 18, ll. 5-9.
F 115. Leung Claim 9 was specific to TiN films and required “treating the film by applying a bias
voltage to the substrate in the presence of a plasma of a precursor gas.” Application
09/128,143, Specification, p. 19, ll. 11-15.
The “Copied Claims”
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F 116. Leung provoked this interference by submitting a preliminary amendment cancelling original
Claims 1-12 and adding new claims 13-28. Application 09/128,143, Paper 4, pp. 1-5.
F 117. Leung’s new Claims 13 and 20, the only independent claims, were said to be “substantially
copied” from Sandhu Claims 27 and 28. Application 09/128,143, Paper 4, p. 6.
F 118. None of Leung’s Claims 13-28 require either bombarding the film with high energy ions or
exposing the film to a plasma while applying a bias voltage.
F 119. Leung’s involved Claim 13 requires only that
after depositing said layer, post-treating said wafer in said reactor with
hydrogen gas and generating plasma to reduce the carbon content of said layer
and thereby decrease the resistivity of said layer.
Application 09/128,143, Paper 4, p. 2.
F 120. Leung’s Claim 20 is essentially the same except that the layer is specified to be a metal
nitride:
after depositing said layer, post-treating said wafer in said reactor with
hydrogen gas and generating plasma to reduce the carbon content of said
metal nitride and thereby decrease the resistivity of said layer.
Application 09/128,143, Paper 4, pp. 3-4.
Findings on written description
F 121. The preliminary amendment filed August 3, 1998 (Application 09/128,143, Paper 4) is not
part of the original specification of the 143 Application and can not be relied upon as part of
Leung’s original disclosure.
F 122. The invention described in the original specification of the 143 Application is a process
utilizing a post treatment with a plasma and high energy ions such as created by applying a
bias voltage during the post-treatment.
F 123. The original specification of the 143 Application does not convey possession of a process for
reducing resistivity of CVD films without applying high energy ions to the film.
F 124. The only way described in the original 143 Specification for significantly reducing resistivity
without introducing undesired impurities employs a post-treatment with a plasma while
applying a biasing voltage.
F 125. The written description of the 143 Specification does not describe reducing resistivity of CVD
films by post-treating with plasma without also subjecting the film to high energy ions.
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F 126. The original 143 Specification does not describe reducing the carbon content of CVD films.
F 127. The original 143 Specification does not describe reducing resistivity of CVD films by treating
with a hydrogen plasma.
F 128. The original 143 Specification does not describe reducing carbon content of CVD films by
post-treating with a hydrogen plasma.
F 129. The original 143 Specification does not describe increasing the resistive stability of CVD
films by post-treating with a hydrogen plasma.
ANALYSIS
Sandhu Preliminary Motion 2
Sandhu’s Preliminary Motion 2 seeks a judgment that Leung’s involved claims are
unpatentable under 35 U.S.C. § 112, ¶ 1. Sandhu argues that Leung’s involved claims, which were
added to the Leung application to provoke an interference with Sandhu’s patent, are not supported
by Leung’s original disclosure. In particular, Sandhu argues that Leung’s original specification
provides neither a written description nor an enabling disclosure of Leung’s involved claims. We
grant the motion with respect to written description and deny it with respect to enabling disclosure..
The Content of the Original 143 Specification
In addition to the original specification and drawings, two other papers, filed as part of the
original 143 Application papers, potentially affect the content of Leung’s disclosure: (1) the
transmittal or cover letter titled Patent Application which was apparently submitted with Leung’s
original 143 Application papers and (2) the preliminary amendment (Application 09/128,143, Paper
4). Both papers purport to incorporate by reference additional subject matter from the parent
applications. We do not have to consider either the propriety of the incorporation by reference or
whatever additional disclosure may be present in those applications. Leung has specifically
disclaimed reliance on any additional subject matter present in those applications to support the
involved claims. Paper 104, p. 15.
Written Description
A.
The general test for determining whether later claimed subject matter is supported by a written
description is whether the disclosure of the application “reasonably conveys to a person skilled in the
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art that the inventor had possession of the claimed subject matter at the time of the earlier filing
date.” Eiselstein v. Frank, 52 F.3d 1035, 1039, 34 USPQ2d 1467, 1470 (Fed. Cir. 1995); Ralston
Purina Co. v. Far-Mar-Co., Inc, 772 F.2d 1570, 1575, 227 USPQ 177, 179 (Fed. Cir. 1985); In re
Kaslow, 707 F.2d 1366, 1375, 217 USPQ 1089, 1096 (Fed. Cir. 1983). The specification must
provide information that clearly allows persons having ordinary skill in the art to recognize that the
applicant invented what is claimed. Vas-Cath Inc. v. Mahurkar, 935 F.2d 1555, 1563-64, 19 USPQ2d
1111, 1116 (Fed. Cir. 1991); In re Gosteli, 872 F.2d 1008, 1012, 10 USPQ2d 1614, 1618 (Fed. Cir.
1989). In Vas-Cath the court noted that the disclosure must “convey with reasonable clarity to those
skilled in the art that. . . [the inventor] was in possession of the invention.” Vas-Cath, 935 F.2d at
1563-64, 19 USPQ2d at 1117 (emphasis original). The court went on to state that the “invention is,
for the purpose of the