DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This office action is in response to applicant’s Restriction/Election filed on 01/05/2026.
Currently claims 1-20 are pending in the application.
Election/Restrictions
Applicant's election without traverse of Group I, claims 1-10, in the reply filed on 01/05/2026 is acknowledged.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 05/16/2024 and 10/29/2024 were filed before the mailing date of the office action. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements were considered by the examiner.
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.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim 1 is rejected under 35 U.S.C. 103 as being unpatentable over US 2024/0355619 A1 (Linthicum) and further in view of US 2008/0169474 A1 (Sheppard).
Regarding claim 1, Linthicum discloses, a Doherty amplifier (700; Doherty amplifier; Fig. 8; [0067] – [0074]) comprising:
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a main amplifier (716; main amplifier; Fig. 8; [0068]) and a peaking amplifier (720; peaking amplifier; Fig. 8; [0068]) that are electrically connected to a same input signal source (RF input signal; Fig. 8; [0068]) and comprise epitaxial structures of a Group III nitride material (layer 112 is an epitaxially grown layer comprising one or more layers of Group III nitride material; Fig. 3; [0012]).
But Linthicum fails to teach explicitly, the nitride material comprising different epitaxial structures.
However, in analogous art, Sheppard discloses, the nitride material comprising different epitaxial structures ([0030]).
Note: Sheppard teaches in para. [0029] – [0030] that it is desirable to integrate various nitride devices together on a single substrate for more efficient manufacturing and/or operation. Therefore, a monolithic electronic device including a common nitride epitaxial layer, a first type of nitride device including a first epitaxial nitride structure on the common nitride epitaxial layer, and a second type of nitride device, different from the first type of nitride device, including a second epitaxial nitride structure on the common nitride epitaxial layer has been implemented.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, having the teachings of Linthicum and Sheppard before him/her, to modify the teachings of a Doherty amplifier with the main and peaking amplifiers as taught by Linthicum and to include the teachings of nitride devices comprising different epitaxial structures as taught by Sheppard and implement different epitaxial structures of Group III nitride material for the main and peaking amplifiers of Doherty amplifier since the main and peaking amplifiers of Doherty amplifier have different requirements to make a good amplifier with target specifications. Absent this important teaching in Linthicum, a person with ordinary skill in the art would be motivated to reach out to Sheppard while forming a Doherty amplifier of Linthicum.
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Linthicum and Sheppard as applied to claim 1 and further in view of US 2021/0398971 A1 (Som).
Regarding claim 7, the combination of Linthicum and Sheppard fails to teach explicitly, the Doherty amplifier of claim 1, wherein the Group III nitride material comprises Aluminum Gallium Nitride (AIGaN).
However, in analogous art, Som discloses, the Doherty amplifier of claim 1, wherein the Group III nitride material comprises Aluminum Gallium Nitride (AIGaN) ([0056]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, having the teachings of Linthicum, Sheppard and Som before him/her, to modify the teachings of a Doherty amplifier with Group III nitride material as taught by Linthicum and to include the teachings of Group III nitride material comprising Aluminum Gallium Nitride as taught by Som since in MPEP 2143 (I) (A), Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Linthicum, a person with ordinary skill in the art would be motivated to reach out to Som while forming a Doherty amplifier of Linthicum.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Linthicum and Sheppard as applied to claim 1 and further in view of US 2021/0320625 A1 (Hashinaga).
Regarding claim 10, the combination of Linthicum and Sheppard fails to teach explicitly, the Doherty amplifier of claim 1, wherein the main amplifier and/or the peaking amplifier further comprises a dielectric interlayer.
However, in analogous art, Hashinaga discloses, the Doherty amplifier of claim 1, wherein the main amplifier (1; high frequency amplifier ; Fig. 9; [0024]) and/or the peaking amplifier further comprises a dielectric interlayer (11; first dielectric layer; Fig. 9; [0030]).
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Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, having the teachings of Linthicum, Sheppard and Hashinaga before him/her, to modify the teachings of a Doherty amplifier as taught by Linthicum and to include the teachings of main amplifier and/or the peaking amplifier further comprising a dielectric interlayer as taught by Hashinaga since in MPEP 2143 (I) (A), Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Linthicum, a person with ordinary skill in the art would be motivated to reach out to Hashinaga while forming a Doherty amplifier of Linthicum.
Allowable Subject Matter
Claims 2-6 and 8-9 are objected to as being dependent upon rejected base claims, but would be allowable if rewritten in independent forms including all of the limitations of the base claims and any intervening claims.
Regarding claim 2, the closest prior art, US 2024/0355619 A1 (Linthicum), in combination with US 2008/0169474 A1 (Sheppard), US 2021/0398971 A1 (Som) and US 2021/0320625 A1 (Hashinaga), fails to disclose, “the Doherty amplifier of claim 1, wherein the epitaxial structure of the peaking amplifier provides the peaking amplifier with a higher power density than the epitaxial structure of the main amplifier”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 3, the closest prior art, US 2024/0355619 A1 (Linthicum), in combination with US 2008/0169474 A1 (Sheppard), US 2021/0398971 A1 (Som) and US 2021/0320625 A1 (Hashinaga), fails to disclose, “the Doherty amplifier of claim 1, wherein the epitaxial structure of the main amplifier provides the main amplifier with a higher gain than the epitaxial structure of the peaking amplifier”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 4, the closest prior art, US 2024/0355619 A1 (Linthicum), in combination with US 2008/0169474 A1 (Sheppard), US 2021/0398971 A1 (Som) and US 2021/0320625 A1 (Hashinaga), fails to disclose, “the Doherty amplifier of claim 1, wherein the epitaxial structure of the main amplifier provides the main amplifier with a higher transconductance than the epitaxial structure of the peaking amplifier”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 5, the closest prior art, US 2024/0355619 A1 (Linthicum), in combination with US 2008/0169474 A1 (Sheppard), US 2021/0398971 A1 (Som) and US 2021/0320625 A1 (Hashinaga), fails to disclose, “the Doherty amplifier of claim 1, wherein the epitaxial structure of the peaking amplifier enables the peaking amplifier to have a higher maximum current than the epitaxial structure of the main amplifier”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 6, the closest prior art, US 2024/0355619 A1 (Linthicum), in combination with US 2008/0169474 A1 (Sheppard), US 2021/0398971 A1 (Som) and US 2021/0320625 A1 (Hashinaga), fails to disclose, “the Doherty amplifier of claim 1, wherein the epitaxial structure of the main amplifier provides the main amplifier with more linear amplification than the epitaxial structure of the peaking amplifier”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 8, the closest prior art, US 2024/0355619 A1 (Linthicum), in combination with US 2008/0169474 A1 (Sheppard), US 2021/0398971 A1 (Som) and US 2021/0320625 A1 (Hashinaga), fails to disclose, “the Doherty amplifier of claim 1, wherein the epitaxial structure of the main amplifier and the peaking amplifier comprise different polarities”, in combination with the additionally claimed features, as are claimed by the Applicant.
Claim 9 is also objected to due to its dependence on an objected base claim.
Examiner’s Note (Additional Prior Arts)
The examiner included a few prior arts which were not used in the rejection but are relevant to the disclosure.
US 2022/0102294 A1 (Zhao) - A semiconductor device is disclosed including a substrate, a first transistor and a second transistor, wherein the first transistor and the second transistor are formed on the substrate, and an isolation structure formed on the substrate. The isolation structure can be formed on the substrate between the first transistor and the second transistor. The isolation structure can be configured to isolate the first transistor and the second transistor.
WO 2021/262538 A1 (Komposch) - A radio frequency (RF) transistor amplifier package is disclosed including a sub-mount, and first and second leads extending from a first side of the sub-mount. The first and second leads are configured to provide RF signal connections to one or more transistor dies on a surface of the sub-mount. At least one rivet is attached to the surface of the sub-mount between the first and second leads on the first side. One or more corners of the first side of the sub-mount may be free of rivets.
US 2020/0014342 A1 (Jones) - A multi-path power amplifier is disclosed including a first semiconductor die with an integrated first transistor having a first source-to-drain pitch, and a second semiconductor die with an integrated second transistor having a second source-to-drain pitch, where the second source-to-drain pitch is smaller than the first source-to-drain pitch by at least 30 percent. In another example embodiment, a Doherty amplifier system includes a first semiconductor die with a first physical die area to total gate periphery ratio, and a second semiconductor die with a second physical die area to total gate periphery ratio, where the second physical die area to total gate periphery ratio is smaller than the first physical die area to total gate periphery ratio by at least 30 percent.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to S M SOHEL IMTIAZ whose telephone number is (408) 918-7566. The examiner can normally be reached on 8AM-5PM, M-F, PST.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Christine S. Kim can be reached at 571-272-8458. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/S M SOHEL IMTIAZ/Primary Patent Examiner
Art Unit 2812
02/28/2026