DETAILED ACTION
Table of Contents
I. Notice of Pre-AIA or AIA Status 3
II. Claim Rejections - 35 USC § 103 3
A. Claims 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over US 2023/0113965 (“Liu”) in view of US 2017/0352624 (“Yang”). 3
III. Response to Arguments 10
Conclusion 11
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I. Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
II. Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
A. Claims 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over US 2023/0113965 (“Liu”) in view of US 2017/0352624 (“Yang”).
Claim 1 reads,
1. (Currently Amended) A method for manufacturing a semiconductor device, comprising:
[1] depositing metal sputtered from a metal target on a semiconductor structure having a recess, so as to fill the recess; and
[2] nitriding the metal deposited on the semiconductor structure to turn the metal into dielectric;
[3] wherein the metal deposited on the semiconductor structure is nitrided using NH3-plasma.
With regard to claim 1, Liu discloses, generally in Figs. 3-4,
1. (Currently Amended) A method for manufacturing a semiconductor device [¶¶ 1, 2], comprising:
[1] depositing metal 304A [¶ 24] sputtered from a metal target [604 in Fig. 6A (¶ 33) and 965 in rectangle (should be “914”) in Fig. 6B (¶ 37); see explanation below] on a semiconductor structure 202 having a recess 204, so as to fill the recess 204 [as shown in Fig. 3]; and
[2] nitriding the metal 304A deposited on the semiconductor structure to turn the metal into dielectric 304-T [as shown in Fig. 4];
[3] wherein the metal deposited on the semiconductor structure 202 is nitrided using …[a N-containing]… plasma [¶ 26]. 304A
With regard to feature [1] of claim 1, while Liu does not state that the substrate 202 is a semiconductor substrate, Liu states that it is the point of the invention disclosed in Liu to process semiconductor substrates, at least for the purposes of forming dielectric isolations in semiconductor substrates, stating in this regard,
[0001] Embodiments of the present principles generally relate to semiconductor processing of semiconductor substrates.
[0002] Various dielectric materials are used in semiconductor features to facilitate in electrically isolating structures. …
(Liu: ¶¶ 1, 2; emphasis added)
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to make the substrate 202 from a semiconductor material because Liu states that that it is the point of the invention to form dielectric isolation features in features formed in a semiconductor substrate (id.).
With regard to features [2] and [3] of claim 1 and claim 8,
8. (Currently Amended) The method according to claim 1, wherein the metal deposited on the semiconductor structure is nitrided at a temperature that falls within a range of from 18 ℃ to 300 ℃ .
Liu states,
[0026] In block 104, the seamless metal gap fill is treated by oxidizing or nitridizing the metal material of the seamless metal gap fill with an oxidation process or a nitridation process to form a dielectric gap fill with a seamless high-k dielectric material. For the sake of brevity, examples of some embodiments may be given using oxidation processes but are not meant to be limiting as nitridation processes may be used as well to convert the metal material to a seamless dielectric material. In some embodiments for a single cycle process, the full seamless metal gap fill 304A is treated 402A by a thermal process or a plasma-assisted process to convert the metal material of the full seamless metal gap fill 304A into a seamless dielectric gap fill of treated full seamless metal gap fill 304A-T from top to bottom as depicted in a view 400A of FIG. 4.
(Liu: ¶ 26; emphasis added)
Thus, while oxidation is primarily discussed, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to nitridize the metal gap fill 304A to convert it into a dielectric gap fill 304A-T, i.e. a metal nitride, because Liu explicitly suggests this (id.).
Because the metal is nitridized, a source of nitrogen is inherently required in order to form active nitrogen species in the plasma. Liu does not, however, provide any examples of nitrogen sources the other plasma nitridation conditions such as the temperature, as required by claim 8.
Yang, like Liu, converts a deposited metal layer 22 of, e.g. Al and Hf (Yang: ¶ 66; Fig. 7) to a metal nitride layer 24 (Yang: ¶ 69; Fig. 8), using a plasma nitridation process (Yang: ¶ 72. Yang further teaches that the nitrogen source for the nitridizing plasma can be made from, e.g., nitrogen (N2) or ammonia (NH3):
[0072] In addition to a thermal nitridation process, the treatment process that coverts the metal layer 22 into the metal nitride layer 24 can include a plasma nitridation process. When a plasma nitridation process is employed, an electrical bias of greater than 200 W can be employed. The plasma nitridation process is performed by generating a plasma from one of the nitrogen-containing ambients that is mentioned above for the thermal nitridation process [¶ 70, infra]. In one embodiment, the plasma nitridation process employed in the present application is performed at a temperature from 50° C. to 450° C. In another embodiment, the plasma nitridation process employed in the present application is performed at a temperature from 100° C. to 300° C.
[0070] … The nitrogen-containing ambients that can be employed in the present application include, but are not limited to, N2, NH3, NH4, NO, or NHx wherein x is between 0 and 1.
(Yang: ¶¶ 72, 70; emphasis added )
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to use N2 or NH3 as the nitrogen source and a temperature of 100° C to 300° C in the nitridizing plasma process of Liu because Liu is merely silent as to the nitrogen source for the plasma and the nitridation temperature, such that one having ordinary skill in the art would use known sources of nitrogen and plasma nitridation temperatures that are capable of plasma nitridizing metal into metal nitride, such as the N2 or NH3 nitrogen sources and temperatures in the range of 100° C. to 300° C that are taught in Yang to be suitable. As such, the selection of N2 or NH3 amounts to obvious material choice. (See MPEP 2144.07.)
This is all of the features of claim 1.
With regard to claims 2-5, Liu further discloses,
2. (Original) The method according to claim 1, wherein the metal sputtered from the metal target is ionized [Liu: abstract; ¶¶ 5, 7, 9, 11, 23-25, 31, claim 1; i.e. “high metal ionization”].
3. (Original) The method according to claim 1, wherein the semiconductor structure 202 is biased with a voltage while the metal is being sputtered and deposited [Liu: Fig. 6B; ¶ 38; ¶ 40: “An RF power source 980 may be coupled to the process chamber 902 through the substrate support 908 to provide a bias power between the target 914 and the substrate support 908.”].
4. (Original) The method according to claim 1, wherein the metal sputtered from the metal target [rectangular structure with “965” at top of chamber in Fig. 6B, which should be labeled “914” (see explanation under feature [1] of claim 1, above)] is collimated [by collimator 918] to travel in a direction perpendicular to the semiconductor structure 202 [Liu: ¶¶ 36-37; Fig. 6B].
5. (Original) The method according to claim 1, wherein the metal is sputtered and deposited under a pressure that falls within a range of from 50 mtorr to 400 mtorr [Liu: ¶¶ 7, 24, 33, claims 3 and 14; i.e. 50 mTorr to 500 mTorr].
Thus the claimed range falls within the range disclosed in Liu. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); MPEP 2144.05(I)). In such a situation, Applicant must show that the particular ranges are critical, generally by showing that the claimed range achieves unexpected results relative to the prior art range. See In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). (See MPEP 2144.05(III)(A); emphasis added.)
With regard to claims 6 and 7, Liu further discloses,
6. (Original) The method according to claim 1, wherein the metal is sputtered and deposited at a temperature that falls within a range of from 18 ℃ to 450 ℃ [Liu: ¶ 40; i.e. 20 ℃ to 400 ℃].
7. (Currently Amended) The method according to claim 1, wherein the metal target 604 includes at least one of Hf, Zr, Ti or W [Liu: ¶ 33]
Claim 9 reads,
9. (Currently Amended) A method for manufacturing a semiconductor device, comprising:
[1] depositing metal sputtered from a metal target on a semiconductor structure having a recess, so as to fill the recess; and
[2] nitriding the metal deposited on the semiconductor structure to turn the metal into dielectric;
[3] wherein the metal deposited on the semiconductor structure is nitrided using N2-plasma.
Claim 9 is distinguished from claim 1 by requiring the N2 instead of NH3 for the plasma nitridation.
As stated above, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to use N2 or NH3 as the nitrogen source and a temperature of 100° C to 300° C in the nitridizing plasma process of Liu because Liu is merely silent as to the nitrogen source for the plasma and the nitridation temperature, such that one having ordinary skill in the art would use known sources of nitrogen and plasma nitridation temperatures that are capable of plasma nitridizing metal into metal nitride, such as the N2 or NH3 nitrogen sources and temperatures in the range of 100° C. to 300° C that are taught in Yang to be suitable. As such, the selection of N2 or NH3 amounts to obvious material choice. (See MPEP 2144.07.)
This is all of the limitations of claim 9.
Claims 10-16 read,
10. (Original) The method according to claim 9, wherein the metal sputtered from the metal target is ionized.
11. (Original) The method according to claim 9, wherein the semiconductor structure is biased with a voltage while the metal is being sputtered and deposited.
12. (Original) The method according to claim 9, wherein the metal sputtered from the metal target is collimated to travel in a direction perpendicular to the semiconductor structure.
13. (Original) The method according to claim 9, wherein the metal is sputtered and deposited under a pressure that falls within a range of from 50 mtorr to 400 mtorr.
14. (Original) The method according to claim 9, wherein in the metal is sputtered and deposited at a temperature that falls within a range of from 18 ℃ to 450 ℃.
15. (Currently Amended) The method according to claim 9, wherein the metal target includes at least one of Hf, Zr, or W.
16. (Currently Amended) The method according to claim 9, wherein the metal deposited on the semiconductor structure is nitrided at a temperature that falls within a range of from 18 ℃ to 300 ℃.
See the discussions under claims 2-8, respectively.
Claim 17 reads,
17. (Currently Amended) A method for manufacturing, a semiconductor device, comprising:
[1] depositing metal sputtered from a metal target on a semiconductor structure having a recess, so as to fill the recess; and
[2] performing a chemical reaction on the metal deposited on the semiconductor structure to turn the metal into dielectric;
[3] wherein the chemical reaction is performed using NH3-plasma or N2-plasma.
Claim 9 is distinguished from claim 1 by requiring the N2 instead of NH3 for the plasma nitridation.
As stated above, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to use N2 or NH3 as the nitrogen source and a temperature of 100° C to 300° C in the nitridizing plasma process of Liu because Liu is merely silent as to the nitrogen source for the plasma and the nitridation temperature, such that one having ordinary skill in the art would use known sources of nitrogen and plasma nitridation temperatures that are capable of plasma nitridizing metal into metal nitride, such as the N2 or NH3 nitrogen sources and temperatures in the range of 100° C. to 300° C that are taught in Yang to be suitable. As such, the selection of N2 or NH3 amounts to obvious material choice. (See MPEP 2144.07.)
This is all of the limitations of claim 17.
Claim 18 reads,
18. (Currently Amended) The method according to claim 17, wherein the metal target includes at least one of Hf, Zr, Ti, or W.
See discussion under claim 7.
With regard to claim 19,
19. (Original) The method according to claim 17, wherein the chemical reaction includes nitridation.
See discussion under claims 17.
With regard to claim 20,
20. (Original) The method according to claim 17, wherein the metal sputtered from the metal target is ionized.
See discussion under claim 2.
III. Response to Arguments
Applicant’s arguments filed 03/23/2026 have been fully considered but they are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
Applicant’s amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ERIK KIELIN whose telephone number is (571)272-1693. The examiner can normally be reached Mon-Fri: 10:00 AM-7:00 PM.
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Signed,
/ERIK KIELIN/
Primary Examiner, Art Unit 2814
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