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 .
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.
Response to Amendment
The following office action is in response to the amendment and remarks filed on 12/9/25.
Applicant’s amendment to claims 1, 8 and 17 is acknowledged.
Claims 1-20 are pending and subject to examination at this time.
Response to Arguments
Applicant's arguments filed 12/9/25 have been fully considered but they are not persuasive.
Applicant submits at page 7-
However, Liang fails to disclose that the liquid metal layer is formed during metal- semiconductor junction epitaxy of the doped semiconductor layer. In other words, Liang’s liquid metal layer is already present before the plasma-assisted MBE, it is not formed during the plasma-assisted MBE, let alone being formed during any metal-semiconductor junction epitaxy.
In response-
Liang’s liquid metal layer is formed during the plasma-assisted MBE.
See Liang at Section II. Methods disclosing:
All the device structure films were grown under the liquid-metal conditions. This means that during the synthesis process, a thin monolayer of liquid metal uniformly covers the growth surface;….
See Lang at Section III. Results and Discussion:
Under this growth regime, incorporated gallium can be easily re-dissolved to liquid metal because of the weaker Ga-N bond (relative to the stronger Al-N bond); nitrogen on the other hand is probably also difficult to re-sublimate into the vacuum because of the presence of the thin liquid metal layer on the surface. We thus speculate that the higher probability of desorption of incorporated gallium generates more group-III vacancies that become available for Mg incorporation.
“Under this growth regime” means during the epitaxial growth by plasma-assisted MBE, gallium is re-dissolved to liquid metal (e.g. MBE stands for molecular beam epitaxy). Thus, Liang teaches the gallium liquid metal is formed during the plasma-assisted MBE.
Applicant submits at page 7-
Liang describes that the thin monolayer of liquid metal (equated to the claimed “liquid metal layer’) uniformly covers the growth surface during the synthesis process of the heavily doped (Al,Ga)N films by plasma-assisted MBE. However, Liang fails to disclose that the liquid metal layer is formed during metal-semiconductor junction epitaxy of the doped semiconductor layer.
In response-
Applicant’s Abstract discloses:
An epitaxial growth process, referred to as metal-semiconductor junction assisted epitaxy, of ultrawide bandgap aluminum gallium nitride (AlGaN) is disclosed. The epitaxy of AlGaN is performed in metal-rich (e.g., Ga-rich) conditions using plasma-assisted molecular beam epitaxy.
Also see Applicant’s disclosure of plasma-assisted MBE at original specification para. [0010].
Applicants are using plasma-assisted MBE just like Liang is using plasma-assisted MBE.
Liang discloses the same plasma-assisted MBE process as the Applicant to grow an epitaxial film under liquid-metal growth conditions to facilitate incorporation of Mg. (e.g. Liang at Abstract.) Liang just does not give the process the terminology “metal-semiconductor junction epitaxy”.
It appears that Applicants are being their own lexicographer by giving the process the terminology “metal-semiconductor junction epitaxy”. Applying a separate/different terminology to the same process such as “metal-semiconductor junction epitaxy” does not distinguish over the Liang reference because “identity of terminology is not required”.
See MPEP § 2131:
“The identical invention must be shown in as complete detail as is contained in the ... claim.” Richardson v. Suzuki Motor Co., 868 F.2d 1226, 1236, 9 USPQ2d 1913, 1920 (Fed. Cir. 1989). The elements must be arranged as required by the claim, but this is not an ipsissimis verbis test, i.e., identity of terminology is not required. In re Bond, 910 F.2d 831, 15 USPQ2d 1566 (Fed. Cir. 1990).
Applicant submits at page 7-
With regard to the claimed “metal-semiconductor junction epitaxy”, the Office Action, on page 4, concedes, “[i]f the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In response, it is submitted that the product having the features recited in claim 1 is different and/or better than Liang’s product formed by the plasma-assisted MBE as explained below.
In response-
As an initial remark, the Office Action at page 4, indicates Liang teaches the limitations of claim 8. As discussed above, Liang discloses the same plasma-assisted MBE process as the Applicant, but does not give the process the terminology “metal-semiconductor junction epitaxy”.
Thus, claim 8 is not merely rejected based on a product-by-process limitation. The comments on a product-by-process limitation are additional remarks on claim 8.
Applicant submits at page 7-
On the other hand, the as-filed specification describes that, in Al0.75Ga0.25N, Mg concentration of approximately 2x1020 cm-3 was measured, and a resistivity value was 1 Q-cm… However, even with higher Al composition as compared to Liang, the Mg concentration is advantageously higher and the resistivity value is advantageously lower in the structure having the features of claim 1.
In response-
Applicant’s arguments are not commensurate with the scope of the claims. The claims do not recite atomic portions of the AlGaN, the numeric concentration of the Mg or resistivity values. The claims simply requires a “doped semiconductor layer” or “p-doped semiconductor layer”. Liang’s plasma-assisted MBE process forms a “doped semiconductor layer” or “p-doped semiconductor layer” as required by the claims.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1-8, 10 and 13-17 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Liang et al., "Heavy Mg-doping of (Al,Ga)N films for potential applications in deep ultraviolet light-emitting structures", Journal of Applied Physics, 123 (2018): pages 1-7 (from the IDS).
Liang anticipates:
1. A structure comprising (see fig. 3):
a substrate layer (e.g. sapphire);
a doped semiconductor layer (p-AlGaN, EBL) over the substrate layer; and
a liquid metal layer (e.g. See Section II, “a thin monolayer of liquid metal uniformly covers the growth surface”) formed over the doped semiconductor layer during metal-semiconductor junction epitaxy (e.g. plasma-assisted MBE) of the doped semiconductor layer (e.g. See Remarks below.). See Liang at pages 1-7.
Regarding claim 1:
As an initial remark, Applicant’s Abstract and original specification at para. [0010] disclose plasma-assisted MBE. Thus, the claimed “metal-semiconductor junction epitaxy” is plasma-assisted MBE.
Liang discloses the same plasma-assisted MBE process as the Applicant to grow an epitaxial film under liquid-metal growth conditions to facilitate incorporation of Mg. (e.g. Liang at Abstract.) Liang just does not give the process the terminology “metal-semiconductor junction epitaxy”.
See MPEP § 2131:
“The identical invention must be shown in as complete detail as is contained in the ... claim.” Richardson v. Suzuki Motor Co., 868 F.2d 1226, 1236, 9 USPQ2d 1913, 1920 (Fed. Cir. 1989). The elements must be arranged as required by the claim, but this is not an ipsissimis verbis test, i.e., identity of terminology is not required. In re Bond, 910 F.2d 831, 15 USPQ2d 1566 (Fed. Cir. 1990).
Liang teaches the gallium liquid metal is formed during plasma-assisted MBE (-i.e. “metal-semiconductor junction epitaxy” in claim 1) of the doped semiconductor layer,
See Liang at Section II. Methods disclosing:
All the device structure films were grown under the liquid-metal conditions. This means that during the synthesis process, a thin monolayer of liquid metal uniformly covers the growth surface;….
See Lang at Section III. Results and Discussion:
Under this growth regime, incorporated gallium can be easily re-dissolved to liquid metal because of the weaker Ga-N bond (relative to the stronger Al-N bond); nitrogen on the other hand is probably also difficult to re-sublimate into the vacuum because of the presence of the thin liquid metal layer on the surface. We thus speculate that the higher probability of desorption of incorporated gallium generates more group-III vacancies that become available for Mg incorporation.
“Under this growth regime” means during the epitaxial growth by plasma-assisted MBE, gallium is re-dissolved to liquid metal (e.g. MBE stands for molecular beam epitaxy). Thus, Liang teaches the gallium liquid metal is formed during the plasma-assisted MBE.
Furthermore, regarding the product-by-process limitations recited in claim 1:
MPEP 2113, Product-by-Process Claims indicates:
“[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
“Once the examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an unobvious difference between the claimed product and the prior art product.” In re Marosi, 710 F.2d 798, 802, 218 USPQ 289, 292 (Fed. Cir. 1983).
Liang further teaches:
2. The structure of claim 1, (see fig. 3) wherein the doped semiconductor layer comprises a magnesium (Mg)-doped gallium nitride (GaN) layer (e.g. The p-AlGaN EBL is doped with Mg in Section II. The p-AlGaN EBL comprises gallium nitride (GaN).), and wherein the liquid metal layer comprises a liquid gallium (Ga) layer (e.g. See Section III, “Under this growth regime, incorporated gallium can be easily re-dissolved to liquid metal…”) on the Mg-doped GaN layer during epitaxy (e.g. See Section II, molecular beam epitaxy (MBE)) of the doped semiconductor layer, wherein the liquid Ga layer causes formation of a metal-semiconductor junction during the epitaxy of the doped semiconductor layer (e.g. See Section II, “a thin monolayer of liquid metal uniformly covers the growth surface” and the growth surface is the p-AlGaN EBL. Since gallium is a metal and p-AlGaN is a semiconductor, a metal-semiconductor junction is formed.)
3. The structure of claim 2, wherein the Mg-doped GaN layer comprises a portion of a heterostructure (e.g. see heterostructure in fig. 3), wherein the heterostructure further comprises a silicon (Si)-doped GaN layer (e.g. “Si-doped AlGaN cladding layer”), a plurality of GaN-based quantum wells (AlGaN quantum wells), and a p-doped contact layer (see uppermost p-AlGaN layer forming interface with Ni-Au contact). See Section III(B) at page 4.
4. The structure of claim 3, (see fig. 3) further comprising one or more layers between the substrate layer and the heterostructure, wherein the one or more layers are selected from the group consisting of: an undoped aluminum nitride (AlN) buffer layer; an undoped gallium nitride (GaN) layer; and an undoped AlGaN layer (e.g. See AlN buffer and AlGaN/AlN superlattice SPSL), See Section III(B) at page 4.
Regarding claims 5-7:
Liang teaches the limitations as applied to claim 2 above.
Regarding claim 8:
Liang teaches the limitations as applied to claim 1 above.
Furthermore, regarding the product-by-process limitations recited in claim 8:
MPEP 2113, Product-by-Process Claims indicates:
“[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
“Once the examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an unobvious difference between the claimed product and the prior art product.” In re Marosi, 710 F.2d 798, 802, 218 USPQ 289, 292 (Fed. Cir. 1983).
Regarding claims 10:
Liang teaches the limitation as applied to claim 2 above.
Liang further teaches:
13. The semiconductor article of claim 10, wherein the Mg doped AlGaN layer includes a resistivity of less than 5 Ω*cm (e.g. see 1.9 Ω*cm at page 3).
Regarding claims 14:
Liang teaches the limitation as applied to claim 4 above.
Regarding claims 15-16:
Liang teaches a sapphire substrate in fig. 3.
Regarding claim 17:
Liang teaches the limitations as applied to claim 1 above.
Furthermore, regarding the product-by-process limitations recited in claim 17:
MPEP 2113, Product-by-Process Claims indicates:
“[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
“Once the examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an unobvious difference between the claimed product and the prior art product.” In re Marosi, 710 F.2d 798, 802, 218 USPQ 289, 292 (Fed. Cir. 1983).
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) 9 and 18-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Liang, as applied to claims 8 and 17 above.
Regarding claims 9 and 18-20:
Liang is silent regarding the Fermi level and valence band during the fabrication process with metal-semiconductor junction epitaxy or specifically:
9. The semiconductor article of claim 8, wherein the metal-semiconductor junction epitaxy creates a separation between a Fermi level and a valence band at an interface of the liquid metal layer on the p-doped semiconductor layer.
18. The semiconductor device of claim 17, wherein the metal-semiconductor junction assisted epitaxy pins a Fermi level away from a valance band at the growth interface of the liquid metal layer on the p-doped semiconductor layer.
19. The semiconductor device of claim 18, wherein the Fermi level pinned away from the valance band allows formation of a nearly n-type growth front despite p-type dopant incorporation.
20. The semiconductor device of claim 17, wherein:
a Fermi level position is decoupled from Mg incorporation during metal-semiconductor junction assisted epitaxy.
First, the limitations recited in claims 9 and 18-20 are considered functional limitations providing a “scientific explanation” for the fabrication process.
It is inherent or obvious to one of ordinary skill in the art that the functional limitations recited in claims 9 and 18-20 are present because (i) Liang teaches a material (e.g. Mg doped AlGaN) and fabrication process (e.g. plasma-assisted molecular beam epitaxy (MBE) using liquid gallium) that is identical or equivalent to the materials and fabrication process disclosed in Applicant’s specification at para. [0038] – [0042].
See MPEP 2112:
“[T]he discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer.” Atlas Powder Co. v. Ireco Inc., 190 F.3d 1342, 1347, 51 USPQ2d 1943, 1947 (Fed. Cir. 1999). Thus the claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable. In re Best, 562 F.2d 1252, 1254, 195 USPQ 430, 433 (CCPA 1977). (Emphasis added.)
Where applicant claims a composition in terms of a function, property or characteristic and the composition of the prior art is the same as that of the claim but the function is not explicitly disclosed by the reference, the examiner may make a rejection under both 35 U.S.C. 102 and 103, expressed as a 102/103 rejection.
Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977).
“Products of identical chemical composition can not have mutually exclusive properties.” A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990)
Regarding claim 20:
Liang further teaches the limitation “the doped semiconductor layer comprises a magnesium (Mg) doped aluminum gallium nitride (AlGaN) layer” as applied to claim 2 above.
Claim(s) 11 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Liang, as applied to claim 8 above.
Regarding claim 11:
Liang further teaches:
11. The semiconductor article of claim 10, wherein the Mg doped AlGaN layer includes a free hole concentration of approximately 4.5x1017 cm-3 (e.g. See Section III(A) disclosing “up to 6x1017 cm-3”)
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). “[A] prior art reference that discloses a range encompassing a somewhat narrower claimed range is sufficient to establish a prima facie case of obviousness." In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003). See MPEP § 2144.05, Obviousness of Ranges
Referring to MPEP § 2144.05, “…the applicant must show that the particular range is critical, generally by showing that the claimed range achieves unexpected results over the prior art range.” (See also MPEP § 716.02 for a discussion of criticality and unexpected results.)
Regarding claim 12:
12. The semiconductor article of claim 10, wherein the Mg doping concentration is approximately one order of magnitude greater for the metal-semiconductor junction epitaxy including the liquid metal layer, as compared to deposition of Mg doped AlGaN without the liquid metal layer (e.g. See disclosure at Abstract “…Mg impurities that ionize to give free hole carrier concentrations of up to 6x1017 cm-3 …this is an improvement from previous devices made from molecular beam epitaxy-grown materials.)
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 Michele Fan whose telephone number is 571-270-7401. The examiner can normally be reached on M-F from 7:30 am to 4 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Jeff Natalini, can be reached on (571) 272-2266. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Michele Fan/
Primary Examiner, Art Unit 2818
23 February 2026