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 .
DETAILED ACTION
Response to Amendment
Applicant’s Amendment filed on June 26, 2026 has been fully considered and entered.
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.
Claims 1, 2, 4, 6-9, 11-18, 30 and 32 are rejected under 35 U.S.C. 103 as being unpatentable over Park et al. (US 2007/0133636 A1) in view of Berk et al. (US 2022/0246781 A1).
Regarding claims 1 and 30, Park discloses a method of manufacturing a waveguide (WG) device and a waveguide device comprising a p-type material, an i-type material and an n-type materials (abstract describes a PIN photodiode), the waveguide device comprising: a semi-insulating (SI) indium phosphide (InP) substrate (10 in Fig. 1; paragraph 0026); an epitaxial layer stack formed on the SI:InP substrate structured to form the PIN waveguide, the epitaxial layer stack comprising: an n-layer structure (12, 14) and a p-layer structure (22, 24, 26); an i-region (16, 18, 20) comprising optical material having an operational wavelength range located between the n-layer structure and the p-layer structure (Fig. 1; paragraph 0027); the n-layer structure and the p-layer structure configured to optical confine one or more modes of an optical signal configured to propagate through the i-region (n-layer structure and p-layer structure confine the mode by virtue of lower refractive index n-diluted index layer 12 and p-diluted index layer 24; see paragraph 0029); and further comprising a mode-extending layer in at least one of the n-layer structure and the p-layer structure (paragraph 0033 describes light guided through core 36 which includes p-1.1Q layer 22; thus, it is a mode extending layer).
Still regarding claims 1 and 30, Park teaches the claimed invention except for disclosing the thickness of the i-region to balance capacitance and a transit time of carriers. Berk discloses a waveguide PIN device (abstract; Fig. 1) comprising an n-layer structure (125) and a p-layer structure (175) and an intrinsic region (105) wherein the thickness of the i-region is selected to balance a capacitance of the i-region and a transit time of carriers comprising at least one of holes and electrons (paragraphs 0003, 0019, 0061). Since both inventions relate to PIN photodetectors, one of ordinary skill in the art at the time of the invention would have found it obvious to select the thickness of the i-region to balance capacitance and a transit time of carriers as disclosed by Berk in conjunction with the optical device of Park for the purpose of providing appropriate levels of sensitivity and modulation speed. In the proposed combination, one of ordinary skill in the art would find it obvious to select the thickness of the light absorption layer 18 in combination with any mode-extending layers in order to accommodate absorption of the modes in the i-region.
Regarding claim 2, Park discloses the waveguide device is a waveguide-photodiode, and the i-region is an absorptive optical material in the abstract and paragraph 0031.
Regarding claim 4, Park discloses the n-layer structure includes at least one of an n-cladding layer (top layer of n-substrate acts as a cladding since it doesn’t guide light) and the p-layer structure includes a p-cladding layer (26).
Regarding claim 6, Park discloses the mode-extending layer comprises a quarternary material fabricated with group III-V semiconductor materials in paragraph 0028.
Regarding claims 7-9, Park discloses the mode-extending layer comprises a first separate p-type layer (22) in the p-layer structure and a separate mode-extending layer comprising an n-type layer (14) and having a refractive index higher than a refractive index of another layer of the n-layer structure and the p-layer structure in the n-layer structure in Fig .1 and paragraphs 0029 and 0031.
Regarding claim 11, Park performance of the device achieved by balancing at least one of parameters of a compositions, size, materials or doping of the epitaxial layer stack; inclusion of one or more mode-shaping structures; and defining a refractive layer of each layer in the epitaxial layer stack (see paragraphs 0010-0011 and 0028-0030, which constitutes balancing of the parameters).
Regarding claim 12, Park discloses the material of the i- region comprises InGaAs in paragraph 0026.
Regarding claims 13-17, the proposed combination of Park and Berk teaches the claimed invention except for the material of the i-region. However, quaternary materials within the InGaAlAsP system as well as multi-quantum well (MQW) structures are well-known and commonly used in the art, and as such it would have been obvious to one having ordinary skill in the art at the time of the invention to form the i-region from the claimed materials in order to enhance absorption in the intrinsic region, and since 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, 125 USPQ 416. Further, it would have been obvious to one having ordinary skill in the art at the time of the invention to arrive at the claimed number of wells and barriers as well as thickness of the wells and barriers, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 18, the proposed combination of Park and Berk teaches the claimed invention except for a width of the i-region is tapered. However, optical waveguides having a tapered width are ubiquitous in the art of optical devices and as such, one of ordinary skill in the art at the time of the invention would have found it obvious to form a width of the i-region to be tapered, having a first width at an optical input and narrowing to a second width at a back facet of the waveguide device in order to adjust the size of the optical mode.
Regarding claim 32, the proposed combination of Park and Berk teaches the claimed invention except for specifically stating the transit time limit. However, it would have been obvious to one having ordinary skill in the art at the time of the invention to arrive at the claimed transit time limit in order to improve the speed of the device, and since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Claims 19-26, 28 and 29 are rejected under 35 U.S.C. 103 as being unpatentable over Park et al. (US 2007/0133636 A1) in view of Berk et al. (US 2022/0246781 A1), further in view of Chandrasekhar et al. (“Eight-Channel p-i-n/HBT Monolithic Receiver Array…” from Applicant’s Information Disclosure Statement filed October 2, 2025).
Regarding claims 19-22 and 26, the proposed combination of Park and Berk teaches the claimed invention except for further comprising a plurality of layers forming at least one electronic device. Chandrasekhar discloses a waveguide device which is a waveguide-photodiode and further comprising a monolithically integrated first plurality of layers of the epitaxial layer stack forming at least one electronic device (“HBT”) which comprises a transimpedance amplifier (TIA) in page 1216. Chandrasekhar further discloses the waveguide-photodiode and the transimpedance amplifier (TIA) are formed monolithically on semi-insulating (SI) indium phosphide (InP) in Fig. 3. Since both inventions relate to PIN photodetectors, one of ordinary skill in the art at the time of the invention would have found it obvious to form an electronic device as disclosed by Chandrasekhar in conjunction with the optical device of the proposed combination of Park and Berk for the purpose of allowing for communication with additional components.
Regarding claims 23 and 29, the proposed combination of Park, Berk and Chandrasekhar teaches the claimed invention except for the optical device being a transmitter. However, receivers are typically used in conjunction with transmitters and as such, one of ordinary skill in the art at the time of the invention would have found it obvious to form the waveguide device as an electro-absorption modulator (EAM) in order to provide emission as well as reception of signals. Further, it would be obvious for one of ordinary skill to form the electronic device as an electro-absorption modulator (EAM) driver in order to control the transmission of the EAM.
Regarding claim 24, Chandrasekhar further discloses InP heterojunction bipolar transistors (HBTs) formed by a first plurality of semiconductor layers of the epitaxial layer stack formed on the SI InP substrate and the waveguide device is formed by a second plurality of semiconductor layers adjacent to the first plurality of semiconductor layers in Fig. 3. The proposed combination of Park, Berk and Chandrasekhar teaches the claimed invention except for specifically stating the second plurality of semiconductor layers overlying the first plurality of semiconductor layers. However, one of ordinary skill in the art at the time of the invention would have found it obvious to form the second plurality of semiconductor layers overlying the first plurality of semiconductor layers for the purpose of conserving space and reducing the size of the device.
Regarding claim 25, Chandrasekhar further discloses the capacitance of the waveguide photodiode on page 1217. The proposed combination of Park, Berk and Chandrasekhar teaches the claimed invention except for specifically stating all of the device parameters. However, the device parameters are typically used in conjunction with photoreceivers and as such, one of ordinary skill in the art at the time of the invention would have found it obvious to account for all of the device parameters in order to enhance operation of the device.
Regarding claim 28, Chandrasekhar in view of the rejection of claim 19 above, further discloses an optical system comprising two or more optical devices on page 1216.
Claims 33-35 are rejected under 35 U.S.C. 103 as being unpatentable over Park et al. (US 2007/0133636 A1) in view of Berk et al. (US 2022/0246781 A1), further in view of Wang et al. (CN 105048283 A from Applicant’s Information Disclosure Statement filed October 17, 2025).
Regarding claims 33-35, the proposed combination of Park and Berk teaches the claimed invention except for processing the width of the i-region. Wang discloses a waveguide device which is a PIN waveguide (see abstract; Fig. 1) and processing the epitaxial stack to define a ridge of the PIN waveguide having a length, a thickness and a width, and wherein a width of the i-region is processed to be to be less than the ridge width (width of active region 4 is less than the ridge width since the ridge includes insulating layer 8 surrounding the active region 4). Since all inventions relate to PIN waveguides, one of ordinary skill in the art at the time of the invention would have found it obvious for a width of the i-region to be less than the ridge width as disclosed by Wang in the proposed combination of Park and Berk for the purpose of forming an isolation channel, allowing for increased versatility in the manufacturing process.
Response to Arguments
Applicant's arguments, see pages 2-3, with respect to claims have been considered but are not persuasive.
On page 2, Applicant asserts that there is no teaching or suggestion of the thickness of the i-region selected for balancing a capacitance of the i-region and a transit time of carriers. Applicant specifically states there is no teaching of “the transit time is reduced to make the device fast (the opposite of the intent of Park) and to reduce the capacitance by not making the i-region too small (not mentioned in Park). However, neither making the device fast nor reducing the capacitance are actually recited in claim 1. As such, they have no bearing on an analysis of the patentability of the claim. The courts have held that claims should be interpreted ‘in view of the specification’ without unnecessarily importing limitations from the specification into the claims.”); Altiris Inc. v. Symantec Corp., 318 F.3d 1363, 1371, 65 USPQ2d 1865, 1869-70 (Fed. Cir. 2003). Berk specifically discloses the thickness of the i-region is selected for balancing a capacitance of the i-region and a transit time of carriers (paragraph 0003: “the thicker the intrinsic region of the PIN-type photodiode, the greater the capacitance of the PIN-type photodiode and, resultantly, the slower the modulation speed”; paragraph 0061: “[thickness of the layers of the i-region] may be configured to provide a reduced and/or minimized capacitance (with respect to the capacitance of conventional PIN-type photodiodes) at a reduced and/or minimized photoinduced/hole transit time”).
On page 2, Applicant further states that Park’s layer 22 is “not a mode extending layer as claimed and instead functions to guide light through the core (36).” However, layer 22 extends the mode by allowing it to be guided beyond the intrinsic i-region. Claim 1 does not specifically recite any structural elements differentiating between the mode extending layer and Park’s layer 22.
On page 3, Applicant states that Berk teaches a fundamentally different device because Berk is directed to vertically illuminated PIN photodiodes whereas the claimed photodiode operates by guiding light laterally along a propagation direction. However, the principle of balancing a capacitance of the i-region and a transit time of carriers is the same and one having ordinary skill in the art would find it obvious to apply the teaching to any PIN-type photodiode.
For the reasons stated above, the prima facie rejection is maintained.
Conclusion
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 CHRIS H CHU whose telephone number is (571)272-8655. The examiner can normally be reached on Mon-Fri 9AM-5PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Uyen-Chau Le can be reached on 571-272-239797. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Any inquiry of a general or clerical nature should be directed to the Technology Center 2800 receptionist at telephone number (571) 272-1562.
Chris H. Chu
/CHRIS H CHU/Primary Examiner, Art Unit 2874 August 19, 2026
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