DETAILED ACTION
General Remarks
In response to Applicant’s Remarks filed on 12/17/2025, claims 1-20 are pending, claims 10-20 are withdrawn from consideration and no new claims appended.
Election/Restrictions
Claims 10-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected method of producing a vertical Schottky diode, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 12/17/2025.
Priority
Applicant’s claim for the benefit of a prior-filed application under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 10/27/2023 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
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.
Claims 1-5 and 8 are rejected under 35 U.S.C. 102(a)(1) and 35 U.S.C. 102(a)(2) as being anticipated by Lu et al. (US 20150318332 A1), hereinafter “Lu.”
Re: Independent Claim 1, Lu discloses a solution-phase processed vertical Schottky diode (Fig. 1 shows a 1D Schottky diode; ¶ [0071]: vertical Schottky diode is Ag/Au, GaZnO, MgxZnO, Au.) comprising:
a stack of films on a substrate (Fig. 1: Ag/Au 112, MgZnO/GaZnO 110, Ag/Au 108, substrate (102); Fig. 4 shows a different embodiment with a substrate 402; Also see ¶ [0070]), the stack of films comprising:
a first electrode film comprising a noble metal (Fig. 1: Ag/Au 112);
a first semiconducting film on the first electrode film (Fig. 1: MgZnO), the first semiconducting film comprising zinc oxide doped with an electron donor metal at a first dopant concentration (¶ [0052]: Mg.sub.xZn.sub.1-xO, formed by alloying ZnO with MgO.; ¶ [0055]: In an embodiment, good diode performance may be obtained on a Mg0.06 Zn0.94O film, i.e., first dopant concentration. Therefore, Mg.sub.xZn.sub.1-xO is expected to reduce the reverse current of the diode compared to ZnO.; ¶ [0056]: FIG. 1, an SEM image of an embodiment of a MgxZnO Schottky diode… the Schottky contact is formed between an Ag and/or Au top electrode 112 and MgxZnO oxide layer 110);
a second semiconducting film on the first semiconducting film (Fig. 1: GaZnO), the second semiconducting film comprising zinc oxide doped with the electron donor metal at a second dopant concentration higher than the first dopant concentration (¶ [0056]: In an embodiment, the GZO film is heavily doped with a carrier concentration of ˜10.sup.20 cm.sup.−3, and is very conductive… It provides good Ohmic contact to Au and thus improves the Ion of the diode. In addition to GZO, other compounds can be used including Al-doped ZnO (AZO) and In-doped ZnO (IZO); ¶ [0070]: A Ga-doped ZnO (GZO) thin layer (10-nm) was deposited on top of the Au layer to serve as the n+ layer to achieve the ohmic contact.; ¶ [0071]: A highly Ga-doped ZnO (GZO) thin layer is deposited on the Au to serve as the n+-GaZnO layer to realize the ohmic contact in the n-MgxZnO/n+-GaZnO/Au structure.: In other words, the GaZnO layer has a higher dopant concentration which creates an ohmic contact having higher conductivity than the MgZnO layer.); and
a second electrode film on the second semiconducting film, the second electrode film comprising a noble metal (Fig. 1: Au 108).
Re: claim 2, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
Lu further discloses wherein the noble metal of the second electrode film is the same as the noble metal of the first electrode film (Fig. 1 shows a first and second noble metal Au 108 and Au 112).
Re: claim 3, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
Lu further discloses wherein the electron donor metal is selected from the group consisting of aluminum, indium, and gallium (¶ [0056]: In addition to GZO, other compounds can be used including Al-doped ZnO (AZO) and In-doped ZnO (IZO)).
Re: claim 4, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
Lu further discloses wherein the first dopant concentration is selected to form a Schottky contact with the first electrode film (¶ [0052]: Mg.sub.xZn.sub.1-xO, formed by alloying ZnO with MgO.; ¶ [0055]: In an embodiment, good diode, i.e., Schottky diode, performance may be obtained on a Mg0.06 Zn0.94O film, i.e., first dopant concentration of Mg. Therefore, Mg.sub.xZn.sub.1-xO is expected to reduce the reverse current of the diode compared to ZnO.; ¶ [0056]: FIG. 1, an SEM image of an embodiment of a MgxZnO Schottky diode… the Schottky contact is formed between an Ag and/or Au top electrode 112 and MgxZnO oxide layer 110).
Re: claim 5, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
Lu further discloses wherein the second dopant concentration is selected to form a tunneling contact with the second electrode film (¶ [0056]: In an embodiment, the GZO film is heavily doped with a carrier concentration of ˜10.sup.20 cm.sup.−3, and is very conductive… It provides good Ohmic contact, i.e., tunneling contact, to Au and thus improves the Ion of the diode. In addition to GZO, other compounds can be used including Al-doped ZnO (AZO) and In-doped ZnO (IZO); ¶ [0070]: A Ga-doped ZnO (GZO) thin layer (10-nm) was deposited on top of the Au layer to serve as the n+ layer to achieve the ohmic contact.; ¶ [0071]: A highly Ga-doped ZnO (GZO) thin layer is deposited on the Au to serve as the n+-GaZnO layer to realize the ohmic contact in the n-MgxZnO/n+-GaZnO/Au structure.: In other words, the GaZnO layer has a higher dopant concentration which creates an ohmic contact having higher conductivity than the MgZnO layer.).
Re: claim 8, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
Lu further discloses wherein a thickness of some or all of the films in the stack increases in a direction away from the substrate (Fig. 1: Au 108 layer is thinner than the MgZnO layer. In other words, the MgZnO layer is thicker than the Au layer 108 in a direction away from the substrate 102).
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 6 is rejected under 35 U.S.C. 103 as being unpatentable over Lu et al. (US 20150318332 A1) in view of Fogel et al. (US 20140196780 A1), hereinafter “Fogel.”
Re: claim 6, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
However, Lu does not specifically disclose wherein the first dopant concentration is less than 1 at.%, and wherein the second dopant concentration is higher than 1 at.%.
In a similar field of endeavor having to do with customizing AZO Schottky junctions, Fogel discloses wherein the first dopant concentration is less than 1 at.%, and wherein the second dopant concentration is higher than 1 at.% (See Fig. 6: layers 20 and 22; ¶ [0068]: transparent conductive material layer 20 includes an aluminum-doped zinc oxide having an aluminum doping at a first dopant concentration, and the Schottky-barrier-reducing layer 22 includes an aluminum-doped zinc oxide having an aluminum doping at a second dopant concentration… In one example, the first dopant concentration is selected to be in the range from 2.0% atomic concentration or greater, i.e., greater than 1 at.%, and the second dopant concentration is selected to be in the range between 0% and 2.0%, i.e., less than 1 at.%, although different ranges may be selected for the first and second dopant concentrations.).
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the semiconductor layers disclosed in Lu, by substituting layers of aluminum doped zinc oxide with the doping concentrations disclosed in Fogel, in order to create an effective AZO bi-layer structure that provides low internal resistance (e.g., higher aluminum doping concentration layer) while also providing an effective AZO Schottky barrier (e.g., lower aluminum doping concentration layer) (See Fogel, ¶ [0068]).
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Lu et al. (US 20150318332 A1)in view of Zhang et al. (US 20150041751 A1), hereinafter “Zhang.”
Re: claim 7, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
However, Lu does not specifically disclose wherein an areal size of some or all of the films in the stack decreases in a direction away from the substrate.
In a similar field of endeavor, Zhang discloses wherein an areal size of some or all of the films in the stack decreases in a direction away from the substrate (Fig. 4A shows a Schottky diode having a structure where the areal size of the films in the stack decreases in a direction away a substrate; See ¶ [0024]).
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the Schottky structure disclosed in Lu to include a variety of structural modifications, as disclosed in Zhang, in order to produce a desired customization of a nonlinear device such as a Schottky diode (See Zhang, ¶ [0068]) which will allow integration with various devices including, for example, memristors (¶ [0070]).
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Lu et al. (US 20150318332 A1) in view of Fogel et al. (US 20140196780 A1) and Rajan et al. (US 20240014285 A1), hereinafter “Rajan.”
Re: claim 9, Lu discloses all the limitations of the solution-phase processed vertical Schottky diode of claim 1.
Lu further discloses wherein the noble metal of the second electrode film is the same as the noble metal of the first electrode film (Fig. 1 shows a first and second noble metal Au 108 and Au 112).
…
…
wherein the first dopant concentration is selected to form a Schottky contact with the first electrode film (¶ [0052]: Mg.sub.xZn.sub.1-xO, formed by alloying ZnO with MgO.; ¶ [0055]: In an embodiment, good diode, i.e., Schottky diode, performance may be obtained on a Mg0.06 Zn0.94O film, i.e., first dopant concentration of Mg. Therefore, Mg.sub.xZn.sub.1-xO is expected to reduce the reverse current of the diode compared to ZnO.; ¶ [0056]: FIG. 1, an SEM image of an embodiment of a MgxZnO Schottky diode… the Schottky contact is formed between an Ag and/or Au top electrode 112 and MgxZnO oxide layer 110),
wherein the second dopant concentration is selected to form a tunneling contact with the second electrode film (¶ [0056]: In an embodiment, the GZO film is heavily doped with a carrier concentration of ˜10.sup.20 cm.sup.−3, and is very conductive… It provides good Ohmic contact, i.e., tunneling contact, to Au and thus improves the Ion of the diode. In addition to GZO, other compounds can be used including Al-doped ZnO (AZO) and In-doped ZnO (IZO); ¶ [0070]: A Ga-doped ZnO (GZO) thin layer (10-nm) was deposited on top of the Au layer to serve as the n+ layer to achieve the ohmic contact.; ¶ [0071]: A highly Ga-doped ZnO (GZO) thin layer is deposited on the Au to serve as the n+-GaZnO layer to realize the ohmic contact in the n-MgxZnO/n+-GaZnO/Au structure.: In other words, the GaZnO layer has a higher dopant concentration which creates an ohmic contact having higher conductivity than the MgZnO layer.).
Although Lu discloses that silver (Ag) may be used as an electrode, it does not specifically disclose wherein the noble metal comprises silver, for both the first and second electrode. Furthermore, while Lu discloses that aluminum doped zinc oxide may be used for one of the layers, e.g., the GaZnO layer, it does not specifically disclose wherein the dopant for both layers may be doped with aluminum.
In a similar field of endeavor having to do with Schottky diodes having compositionally graded layers for the purpose of creating Schottky and ohmic contacts, Rajan discloses wherein the noble metal comprises silver (Fig. 2 shows a Schottky diode having electrode layers 102 and 108; ¶ [0007] first electrode layer comprises a Schottky contact layer. In some examples, the first electrode layer comprises a metal selected from the group consisting of … Ag.; Also see ¶ [0054]: first electrode layer 102… Ag; ¶ [0012]: In some examples, the second electrode layer comprises an Ohmic contact layer. In some examples, the second electrode layer comprises … Ag.; Also see ¶ [0073]: second electrode layer 108… Ag).
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the Schottky structure disclosed in Lu to include silver for both the Schottky contact electrode and the ohmic contact electrodes in order to select suitable materials for the purpose of having an improved Schottky barrier height, an improved electric breakdown properties, improved tunneling current, or a combination thereof when the second semiconductor layer is present (See Rajan, ¶ [0076]). 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. In re Leshin, 125 USPQ 416. MPEP 2144.07.
Furthermore, while both Lu in view of Rajan disclose Schottky diode configurations incorporating materials such as Ag and AZO to create diodes similar to the claimed invention, the combination does not specifically disclose wherein the electron donor metal comprises aluminum, for both semiconductor layers.
In a similar field of endeavor having to do with customizing AZO Schottky junctions, Fogel discloses wherein the electron donor metal comprises aluminum (See Fig. 6: layers 20 and 22; ¶ [0068]: transparent conductive material layer 20 includes an aluminum-doped zinc oxide having an aluminum doping at a first dopant concentration, and the Schottky-barrier-reducing layer 22 includes an aluminum-doped zinc oxide having an aluminum doping at a second dopant concentration…).
Therefore, it would have been obvious to a person having ordinary skill in the art before the effective filing date to modify the semiconductor layers disclosed in Lu, by substituting layers of aluminum doped zinc oxide with the doping concentrations disclosed in Fogel, in order to create an effective AZO bi-layer structure that provides low internal resistance (e.g., higher aluminum doping concentration layer) while also providing an effective AZO Schottky barrier (e.g., lower aluminum doping concentration layer) (See Fogel, ¶ [0068]).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Sen Gupta et al. (US 20220199839 A1) – See Fig. 2 and ¶¶ [0013], [0017]
Brew et al. (US 20180309075 A1) – See Fig. 19 and ¶¶ [0049], [0059], [0069-0071]
Kang et al. (US 20080142796 A1) – See Fig. 3
Any inquiry concerning this communication or earlier communications from the examiner should be directed to William Adrovel whose telephone number is 571-272-3048. The examiner can normally be reached on M-F, 8:30AM to 5:00PM (EST).
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/WILLIAM ADROVEL/Examiner, Art Unit 2898
/Leonard Chang/Supervisory Patent Examiner, Art Unit 2898