DETAILED ACTION
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 .
Claim Objections
Claim 21 is objected to because of the following informalities:
“the nickel sub-layer” should read “the first metal sub-layer” (line 1);
Each claim is required to end with a period, but it is unclear if a period is present after “seed layer” (line 2).
Appropriate correction is required.
Claim Rejections - 35 USC § 103
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, 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.
Claim(s) 1, 3-9, 11, 13, 15-19 and 21 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 6,413,851 B1 (hereinafter “Chow”) in view of US 2019/0237421 A1 (hereinafter “Tsuchiya”).
Regarding claim 1, Chow discloses in Fig. 1(j) (see Figs. 1(a)-1(i) for reference numerals omitted from Fig. 1(j)) and related text an electronic device comprising:
a semiconductor substrate (2; col. 3, line 56);
an aluminum pad (4; col. 3, line 59) on the semiconductor substrate; and
a stack comprising, in sequence:
a barrier layer (8 (a lower sub-layer thereof); col. 4, lines 2-10) directly deposited on the aluminum pad;
a seed layer (8 (an upper sub-layer thereof); col. 4, lines 2-7 and 11-13) directly deposited on the barrier layer, the seed layer comprising copper; and
a metal layer (12, 14; col. 4, line 60 and col. 6, lines 37-38) directly deposited on the seed layer,
wherein the metal layer comprises a first metal sub-layer comprising nickel (12; col. 4, line 60) directly deposited on the seed layer and a second metal sub-layer comprising palladium (14; col. 4, line 67 and col. 6, lines 15-16 and 37-38) directly deposited on the first metal sub-layer; and
wherein the second metal sub-layer has a thickness in the range 150-500 nm (col. 2, lines 24-26; note: 0.5 microns = 500 nm).
Chow does not explicitly disclose the seed layer having a thickness less than 800 nanometers (nm).
Tsuchiya teaches in Fig. 9 and related text the seed layer (12; [0066]) having a thickness less than 800 nanometers (nm).
Chow and Tsuchiya are analogous art because they both are directed to semiconductor devices and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow with the specified features of Tsuchiya because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to form the seed layer to have a thickness less than 800 nanometers (nm), as taught by Tsuchiya, in order to keep the opening in Chow’s passivating layer 6 wide to facilitate the subsequent deposition of the nickel layer 12; reduce the time required to etch the exposed portion of the seed layer, as described by Chow in column 6, lines 43-46 and shown in Figs. 1(h) and 1(i); and avoid the risk of peeling of the seed layer resulting from the accumulation of stress as film thickness increases.
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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) (The prior art taught carbon monoxide concentrations of "about 1-5%" while the claim was limited to "more than 5%." The court held that "about 1-5%" allowed for concentrations slightly above 5% thus the ranges overlapped.); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997) (Claim reciting thickness of a protective layer as falling within a range of "50 to 100 Angstroms" considered prima facie obvious in view of prior art reference teaching that "for suitable protection, the thickness of the protective layer should be not less than about 10 nm [i.e., 100 Angstroms]." The court stated that "by stating that ‘suitable protection’ is provided if the protective layer is ‘about’ 100 Angstroms thick, [the prior art reference] directly teaches the use of a thickness within [applicant’s] claimed range."). See also In re Bergen, 120 F.2d 329, 332, 49 USPQ 749, 751-52 (CCPA 1941) (The court found that the overlapping endpoint of the prior art and claimed range was sufficient to support an obviousness rejection, particularly when there was no showing of criticality of the claimed range). MPEP 2144.05(I), first paragraph thereof.
Regarding claim 3, Chow in view of Tsuchiya disclose the first metal sub-layer entirely covers a top surface of the seed layer (the first metal sub-layer 12 entirely covers a first (lower) top surface of the seed layer 8, the first top surface being located within the opening in the passivating layer 6, as shown in Fig. 1(j) of Chow).
Regarding claim 4, Chow in view of Tsuchiya disclose the metal layer consists of the first and second metal sub-layers (the second metal sub-layer 14 directly contacts the first metal sub-layer 12 such that there is no additional metal sub-layer(s) interposed therebetween, as shown in Fig. 1(f) of Chow).
Regarding claim 5, Chow in view of Tsuchiya disclose the electronic device of claim 1.
Chow does not explicitly disclose the seed layer has a thickness of 250-600 nm.
Tsuchiya teaches in Fig. 9 and related text the seed layer (12; [0066]) has a thickness of 250-600 nm.
Chow and Tsuchiya are analogous art because they both are directed to semiconductor devices and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow with the specified features of Tsuchiya because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to form the seed layer to have a thickness of 250-600 nm, as taught by Tsuchiya, in order to keep the opening in Chow’s passivating layer (6) wide to facilitate the subsequent deposition of the nickel layer (12); reduce the time required to etch the exposed portion of the seed layer, as described by Chow in column 6, lines 43-46 and shown in Figs. 1(h) and 1(i); and avoid the risk of peeling of the seed layer resulting from the accumulation of stress as film thickness increases.
Regarding claim 6, Chow in view of Tsuchiya disclose the metal layer has a thickness greater than 500 nm (the first metal sub-layer may have a thickness of about 1 micron = 1000 nm (Chow: col. 4, line 50) and the second metal sub-layer may have a thickness of 0.5 micron = 500 nm (Chow: col. 2, lines 24-26)).
Regarding claim 7, Chow in view of Tsuchiya disclose a sectional view of the seed layer has a substantially constant width from the barrier layer to the metal layer (Chow: Fig. 1(j)).
Regarding claim 8, Chow in view of Tsuchiya disclose the seed layer consists of a single layer of copper (Chow: col. 4, lines 6-7 and 11-13).
Regarding claim 9, Chow in view of Tsuchiya disclose the electronic device of claim 1.
Chow does not explicitly disclose the barrier layer comprises titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride.
Tsuchiya teaches the barrier layer comprises titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride ([0066]).
Chow and Tsuchiya are analogous art because they both are directed to semiconductor devices and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow with the specified features of Tsuchiya because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to form the barrier layer to comprise titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride, as taught by Tsuchiya, at least because titanium acts as a strong adhesion promoter, thereby preventing delamination of the barrier and seed layers from the aluminum pad.
Furthermore, it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 277 F.2d 197, 125 USPQ 416 (CCPA 1960). MPEP 2144.07.
Regarding claim 11, Chow discloses a method of manufacturing an electronic device, the method comprising:
providing an aluminum pad (4; col. 3, line 59) on a semiconductor substrate (2; col. 3, line 56) of the electronic device (Fig. 1(a)); and
forming a stack on the aluminum pad (Figs. 1(b)-1(f)), the forming comprising:
depositing a barrier layer (8 (a lower sub-layer thereof); col. 4, lines 2-10) directly on the aluminum pad (Fig. 1(b));
depositing a seed layer (8 (an upper sub-layer thereof); col. 4, lines 2-7 and 11-13) directly on the barrier layer, the seed layer comprising copper (Fig. 1(b));
depositing a first metal sub-layer comprising nickel (12; col. 4, line 60) directly on the seed layer (Fig. 1(d)), and
depositing a second metal sub-layer comprising palladium (14; col. 4, line 67 and col. 6, lines 15-16 and 37-38) directly on the first metal sub-layer (Fig. 1(f));
wherein the second metal sub-layer has a thickness in the range 150-500 nm (col. 2, lines 24-26; note: 0.5 microns = 500 nm).
Chow does not explicitly disclose the seed layer having a thickness less than 800 nanometers (nm).
Tsuchiya teaches in Fig. 9 and related text the seed layer (12; [0066]) having a thickness less than 800 nanometers (nm).
Chow and Tsuchiya are analogous art because they both are directed to semiconductor manufacturing and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow with the specified features of Tsuchiya because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to form the seed layer to have a thickness less than 800 nanometers (nm), as taught by Tsuchiya, in order to keep the opening in Chow’s passivating layer 6 wide to facilitate the subsequent deposition of the nickel layer 12; reduce the time required to etch the exposed portion of the seed layer, as described by Chow in column 6, lines 43-46 and shown in Figs. 1(h) and 1(i); and avoid the risk of peeling of the seed layer resulting from the accumulation of stress as film thickness increases.
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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) (The prior art taught carbon monoxide concentrations of "about 1-5%" while the claim was limited to "more than 5%." The court held that "about 1-5%" allowed for concentrations slightly above 5% thus the ranges overlapped.); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997) (Claim reciting thickness of a protective layer as falling within a range of "50 to 100 Angstroms" considered prima facie obvious in view of prior art reference teaching that "for suitable protection, the thickness of the protective layer should be not less than about 10 nm [i.e., 100 Angstroms]." The court stated that "by stating that ‘suitable protection’ is provided if the protective layer is ‘about’ 100 Angstroms thick, [the prior art reference] directly teaches the use of a thickness within [applicant’s] claimed range."). See also In re Bergen, 120 F.2d 329, 332, 49 USPQ 749, 751-52 (CCPA 1941) (The court found that the overlapping endpoint of the prior art and claimed range was sufficient to support an obviousness rejection, particularly when there was no showing of criticality of the claimed range). MPEP 2144.05(I), first paragraph thereof.
Regarding claim 13, Chow in view of Tsuchiya disclose depositing the barrier layer and the seed layer are performed via physical vapor deposition (Chow: col. 4, lines 2-4; note: sputter deposition is a type of physical vapor deposition).
Regarding claim 15, Chow in view of Tsuchiya disclose the first metal sub-layer substantially entirely covers a top surface of the seed layer (the first metal sub-layer 12 entirely covers a first (lower) top surface of the seed layer 8, the first top surface being located within the opening in the passivating layer 6, as shown in Fig. 1(j) of Chow).
Regarding claim 16, Chow in view of Tsuchiya disclose the method of claim 11.
Chow does not explicitly disclose the seed layer is deposited with a thickness of 250-600 nm.
Tsuchiya teaches in Fig. 9 and related text the seed layer (12; [0066]) is deposited with a thickness of 250-600 nm.
Chow and Tsuchiya are analogous art because they both are directed to semiconductor manufacturing and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow with the specified features of Tsuchiya because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to deposit the seed layer with a thickness of 250-600 nm, as taught by Tsuchiya, in order to keep the opening in Chow’s passivating layer (6) wide to facilitate the subsequent deposition of the nickel layer (12); reduce the time required to etch the exposed portion of the seed layer, as described by Chow in column 6, lines 43-46 and shown in Figs. 1(h) and 1(i); and avoid the risk of peeling of the seed layer resulting from the accumulation of stress as film thickness increases.
Regarding claim 17, Chow in view of Tsuchiya disclose the metal layer is deposited with a thickness greater than 500 nm (the first metal sub-layer may have a thickness of about 1 micron = 1000 nm (Chow: col. 4, line 50) and the second metal sub-layer may have a thickness of 0.5 micron = 500 nm (Chow: col. 2, lines 24-26)).
Regarding claim 18, Chow in view of Tsuchiya disclose a sectional view of the seed layer has a substantially constant width from the barrier layer to the metal layer (Chow: Fig. 1(j)).
Regarding claim 19, Chow in view of Tsuchiya disclose the seed layer is deposited as a single layer of copper (Chow: col. 4, lines 6-7 and 11-13).
Regarding claim 21, Chow in view of Tsuchiya disclose the nickel sub-layer partially covers a sidewall of the seed layer (the nickel sub-layer 12 directly contacts and at least partially covers an inner, vertically oriented sidewall of the seed layer 8, as shown in Fig. 1(d) of Chow).
Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chow in view of Tsuchiya as applied to claim 1 above, and further in view of US 2013/0320524 A1 (hereinafter “Chuang”).
Regarding claim 10, Chow in view of Tsuchiya disclose the electronic device of claim 1.
Chow in view of Tsuchiya do not explicitly disclose the barrier layer consists of a layer made of titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride.
Chuang teaches in Fig. 2 and related text the barrier layer (201; [0026]) consists of a layer made of titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride.
Chow, Tsuchiya and Chuang are analogous art because they each are directed to semiconductor devices and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow in view of Tsuchiya with the specified features of Chuang because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to form the barrier layer to consist of a layer made of titanium, titanium-nitride, titanium-tungsten, tantalum, and/or tantalum-nitride, as taught by Chuang, at least because titanium acts as both a diffusion barrier and a strong adhesion promoter, thereby preventing delamination of the barrier layer and the seed layer from the aluminum pad.
Furthermore, it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 277 F.2d 197, 125 USPQ 416 (CCPA 1960). MPEP 2144.07.
Claim(s) 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chow in view of Tsuchiya as applied to claim 11 above, and further in view of US 2006/0267203 A1 (hereinafter “Test”).
Regarding claim 12, Chow in view of Tsuchiya disclose the method of claim 11.
Chow in view of Tsuchiya do not disclose depositing the metal layer is performed via electroless deposition.
Test teaches in Figs. 5A, 6A and related text depositing the metal layer (501, 601; [0031]-[0032]) is performed via electroless deposition.
Chow, Tsuchiya and Test are analogous art because they each are directed to semiconductor manufacturing and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow in view of Tsuchiya with the specified features of Test because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to deposit the metal layer via electroless deposition, as taught by Test, because electroless deposition offers superior, uniform thickness on complex shapes without using electrical current.
Claim(s) 22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chow in view of Tsuchiya as applied to claim 1 above, and further in view of US 2019/0164920 A1 (hereinafter “Tsao”).
Regarding claim 22, Chow in view of Tsuchiya disclose the electronic device of claim 1.
Chow in view of Tsuchiya do not disclose the semiconductor substrate is made of silicon carbide.
Tsao teaches in Fig. 3 and related text the semiconductor substrate (12; [0037]) is made of silicon carbide.
Chow, Tsuchiya and Tsao are analogous art because they each are directed to semiconductor devices and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow in view of Tsuchiya with the specified features of Tsao because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to select silicon carbide as the semiconductor substrate, as taught by Tsao, because of the high thermal conductivity of silicon carbide, thereby improving the heat dissipation capability of the electronic device.
Claim(s) 23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chow in view of Tsuchiya and US 2012/0080794 A1 (hereinafter “Sidorov”).
Regarding claim 23, Chow discloses in Fig. 1(j) (see Figs. 1(a)-1(i) for reference numerals omitted from Fig. 1(j)) and related text an electronic device comprising:
a semiconductor substrate (2; col. 3, line 56);
an aluminum pad (4; col. 3, line 59) on the semiconductor substrate; and
a stack comprising, in sequence:
a barrier layer (8 (a lower sub-layer thereof); col. 4, lines 2-10) directly deposited on the aluminum pad;
a seed layer (8 (an upper sub-layer thereof); col. 4, lines 2-7 and 11-13) directly deposited on the barrier layer, the seed layer comprising copper; and
a metal layer (12, 14; col. 4, lines 60 and 67 and col. 6, lines 15-16 and 37-38) directly deposited on the seed layer, the metal layer comprising nickel and palladium.
Chow does not explicitly disclose the seed layer having a thickness less than 800 nanometers (nm), and the aluminum pad has an area of 1000X1000 square micrometers ([Symbol font/0x6D]m2) or of 420X560 [Symbol font/0x6D]m2 or of 2040X1900 [Symbol font/0x6D]m2.
Tsuchiya teaches in Fig. 9 and related text the seed layer (12; [0066]) having a thickness less than 800 nanometers (nm).
Sidorov teaches in Fig. 1 and related text the aluminum pad (20; [0020] and [0031]) has an area between 1 [Symbol font/0x6D]m2 and 0.20 m2 (note: 0.20 m2 = 2×1011 [Symbol font/0x6D]m2). It should be noted that the three area values claimed in claim 23 lie inside Sidorov’s disclosed range.
Chow, Tsuchiya and Sidorov are analogous art because they each are directed to semiconductor devices and one of ordinary skill in the art would have had a reasonable expectation of success to modify Chow with the specified features of Tsuchiya and Sidorov because they are from the same field of endeavor.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to form the seed layer to have a thickness less than 800 nanometers (nm), as taught by Tsuchiya, and to form the aluminum pad to have an area of 1000X1000 square micrometers ([Symbol font/0x6D]m2) or of 420X560 [Symbol font/0x6D]m2 or of 2040X1900 [Symbol font/0x6D]m2, in order to keep the opening in Chow’s passivating layer 6 wide to facilitate the subsequent deposition of the nickel layer 12; reduce the time required to etch the exposed portion of the seed layer, as described by Chow in column 6, lines 43-46 and shown in Figs. 1(h) and 1(i); and avoid the risk of peeling of the seed layer resulting from the accumulation of stress as film thickness increases, and in order to configure the aluminum pad in accordance with the intended use. For example, a wider pad creates more space for electrons to move. This reduces electrical resistance and cuts down on power loss. In addition, current spreads more effectively across a larger area. This avoids hot spots that can burn out the electronic device.
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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) (The prior art taught carbon monoxide concentrations of "about 1-5%" while the claim was limited to "more than 5%." The court held that "about 1-5%" allowed for concentrations slightly above 5% thus the ranges overlapped.); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997) (Claim reciting thickness of a protective layer as falling within a range of "50 to 100 Angstroms" considered prima facie obvious in view of prior art reference teaching that "for suitable protection, the thickness of the protective layer should be not less than about 10 nm [i.e., 100 Angstroms]." The court stated that "by stating that ‘suitable protection’ is provided if the protective layer is ‘about’ 100 Angstroms thick, [the prior art reference] directly teaches the use of a thickness within [applicant’s] claimed range."). See also In re Bergen, 120 F.2d 329, 332, 49 USPQ 749, 751-52 (CCPA 1941) (The court found that the overlapping endpoint of the prior art and claimed range was sufficient to support an obviousness rejection, particularly when there was no showing of criticality of the claimed range). MPEP 2144.05(I), first paragraph thereof.
It should be noted that Applicant’s specification does not assert the criticality of any of the three area values claimed in claim 23. The specification describes in [0028] that these three area values are merely exemplary. The specification states: “Aluminum pads of any area could be used” ([0028], line 5).
Response to Arguments
Applicant’s arguments with respect to claim(s) 1 and 11 have been considered but 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 nonprovisional extension fee (37 CFR 1.17(a)) 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 mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PETER M ALBRECHT whose telephone number is (571)272-7813. The examiner can normally be reached M-F 9:30 AM - 6:30 PM (CT).
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/PETER M ALBRECHT/Primary Examiner, Art Unit 2811
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