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 01/30/2026.
Currently claims 1-14 and 21-26 are pending in the application.
Election/Restrictions
Applicant's election without traverse of Group I, claims 1-14, in the reply filed on 01/30/2026 is acknowledged. The new claims 21-26 are accepted for prosecution.
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 2010/0038736 A1 (Assefa) and further in view of US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu).
Regarding claim 1, Assefa discloses, a photodetector device, comprising:
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a waveguide (20; waveguide; Fig. 7D; [0069]); and
a photodetector (as annotated on Fig. 7D; [0070]), coupled with the waveguide (20), comprising:
a semiconductor substrate (substrate below layer 10; Fig. 7D; [0072]) comprising a first semiconductor material (silicon; [0002]);
a first type doped collection region (60; p-type germanium region; Fig. 7D; [0070]; can be interchanged) in the semiconductor substrate;
a second type doped collection region (62; n-type germanium region; Fig. 7D; [0070]; can be interchanged) in the semiconductor substrate; and
an absorption region (as annotated on Fig. 7D), comprising a second semiconductor material (germanium; [0070]), in the semiconductor substrate between the first type doped collection region (60) and the second type doped collection region (62),
Note: Assefa teaches in para. [0070] that upon interaction with light, the photodetector (60, 62) generates electron-hole pairs as a photodiode. Charge carriers of the second conductivity type are collected in the second-conductivity-type germanium region 62 in proportion to the amount of photons that interact with the photodetector (60, 62). In case the first conductivity type is p-type and the second conductivity type is n-type, electrons are collected in the second-conductivity-type germanium region 62. In case the second conductivity type is n-type and the second conductivity type is p-type, holes are collected in the second-conductivity-type germanium region 62. The examiner attributed the region near the junction of layers 60 and 62 as equivalent to the absorption layer.
wherein the absorption region (small vertical portion of the absorption region, as annotated on Fig. 7D) is approximately parallel with a direction that the photodetector is to receive incident light (as annotated on Fig. 7D) from the waveguide (20);
But Assefa fails to teach explicitly, the semiconductor substrate is intrinsic; wherein the absorption region comprises a stepped profile or a tapered profile in a direction that is approximately parallel with a direction that the photodetector is to receive incident light from the waveguide.
However, in analogous art, Cohen discloses, the semiconductor substrate is intrinsic (intrinsic or undoped; [0039]);
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 Assefa and Cohen before him/her, to modify the teachings of a photodetector device as taught by Assefa and to include the teachings of the semiconductor substrate being intrinsic as taught by Cohen since in MPEP 2143 (I) (A), it is stated that Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Assefa, a person with ordinary skill in the art would be motivated to reach out to Cohen while forming a photodetector device of Assefa.
But the combination of Assefa and Cohen fails to teach explicitly, wherein the absorption region comprises a stepped profile or a tapered profile in a direction that is approximately parallel with a direction that the photodetector is to receive incident light from the waveguide.
However, in analogous art, Wu discloses, wherein the absorption region (300; absorption region; Fig. 3; [0043]) comprises a stepped profile or a tapered profile (tapered profile) in a direction that is approximately parallel with a direction (horizontal) that the photodetector (as annotated on Fig. 3) is to receive incident light from the waveguide (200; waveguide; Fig. 3; [0047]).
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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 Assefa, Cohen and Wu before him/her, to modify the teachings of a photodetector device as taught by Assefa and to include the teachings of an absorption region comprising a tapered profile as taught by Wu since in MPEP 2143 (I) (A), it is stated that Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Assefa, a person with ordinary skill in the art would be motivated to reach out to Wu while forming a photodetector device of Assefa.
Claims 8-9 are rejected under 35 U.S.C. 103 as being unpatentable over US 2010/0038736 A1 (Assefa) and further in view of US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu).
Regarding claim 8, Assefa discloses, a photodetector device, comprising:
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a waveguide (20; waveguide; Fig. 7D; [0069]); and
a photodetector (as annotated on Fig. 7D; [0070]), coupled with the waveguide (20), comprising:
a semiconductor substrate (substrate below layer 10; Fig. 7D; [0072]) comprising a first semiconductor material (silicon; [0002]);
a first type doped collection region (60; p-type germanium region; Fig. 7D; [0070]; can be interchanged) in the semiconductor substrate;
a second type doped collection region (62; n-type germanium region; Fig. 7D; [0070]; can be interchanged) in the semiconductor substrate; and
an absorption region (as annotated on Fig. 7D), comprising a second semiconductor material (germanium; [0070]), in the semiconductor substrate between the first type doped collection region (60) and the second type doped collection region (62),
Note: Assefa teaches in para. [0070] that upon interaction with light, the photodetector (60, 62) generates electron-hole pairs as a photodiode. Charge carriers of the second conductivity type are collected in the second-conductivity-type germanium region 62 in proportion to the amount of photons that interact with the photodetector (60, 62). In case the first conductivity type is p-type and the second conductivity type is n-type, electrons are collected in the second-conductivity-type germanium region 62. In case the second conductivity type is n-type and the second conductivity type is p-type, holes are collected in the second-conductivity-type germanium region 62. The examiner attributed the region near the junction of layers 60 and 62 as equivalent to the absorption layer.
wherein the absorption region (small vertical portion of the absorption region, as annotated on Fig. 7D) is approximately parallel with a direction that the photodetector is to receive incident light (as annotated on Fig. 7D) from the waveguide (20);
But Assefa fails to teach explicitly, the semiconductor substrate is intrinsic; wherein the absorption region comprises a tapered profile in a direction that is approximately parallel with a direction that the photodetector is to receive incident light from the waveguide.
However, in analogous art, Cohen discloses, the semiconductor substrate is intrinsic (intrinsic or undoped; [0039]);
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 Assefa and Cohen before him/her, to modify the teachings of a photodetector device as taught by Assefa and to include the teachings of the semiconductor substrate being intrinsic as taught by Cohen since in MPEP 2143 (I) (A), it is stated that Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Assefa, a person with ordinary skill in the art would be motivated to reach out to Cohen while forming a photodetector device of Assefa.
But the combination of Assefa and Cohen fails to teach explicitly, wherein the absorption region comprises a stepped profile or a tapered profile in a direction that is approximately parallel with a direction that the photodetector is to receive incident light from the waveguide.
However, in analogous art, Wu discloses, wherein the absorption region (300; absorption region; Fig. 3; [0043]) comprises a stepped profile or a tapered profile (tapered profile) in a direction that is approximately parallel with a direction (horizontal) that the photodetector (as annotated on Fig. 3) is to receive incident light from the waveguide (200; waveguide; Fig. 3; [0047]).
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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 Assefa, Cohen and Wu before him/her, to modify the teachings of a photodetector device as taught by Assefa and to include the teachings of an absorption region comprising a tapered profile as taught by Wu since in MPEP 2143 (I) (A), it is stated that Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Assefa, a person with ordinary skill in the art would be motivated to reach out to Wu while forming a photodetector device of Assefa.
Regarding claim 9, Assefa discloses, the photodetector device of claim 8, wherein a depth of a sloped bottom surface of the absorption region (300; Fig. 3; [0043]) increases (as evident in Fig. 3) in a sloped section from a first depth (left) to a second depth (right) in the direction that the photodetector is to receive the incident light (gets incident light from left surface; Fig. 3; [0041] – [0045]).
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Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over US 2010/0038736 A1 (Assefa) and further in view of US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu).
Regarding claim 21, Assefa discloses, a photodetector device, comprising:
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a waveguide (20; waveguide; Fig. 7D; [0069]); and
a photodetector (as annotated on Fig. 7D; [0070]), coupled with the waveguide (20), comprising:
a semiconductor substrate (substrate below layer 10; Fig. 7D; [0072]);
a first type doped collection region (60; p-type germanium region; Fig. 7D; [0070]; can be interchanged) in the semiconductor substrate;
a second type doped collection region (62; n-type germanium region; Fig. 7D; [0070]; can be interchanged) in the semiconductor substrate; and
an absorption region (as annotated on Fig. 7D), in the semiconductor substrate between the first type doped collection region (60) and the second type doped collection region (62),
Note: Assefa teaches in para. [0070] that upon interaction with light, the photodetector (60, 62) generates electron-hole pairs as a photodiode. Charge carriers of the second conductivity type are collected in the second-conductivity-type germanium region 62 in proportion to the amount of photons that interact with the photodetector (60, 62). In case the first conductivity type is p-type and the second conductivity type is n-type, electrons are collected in the second-conductivity-type germanium region 62. In case the second conductivity type is n-type and the second conductivity type is p-type, holes are collected in the second-conductivity-type germanium region 62. The examiner attributed the region near the junction of layers 60 and 62 as equivalent to the absorption layer.
But Assefa fails to teach explicitly, the semiconductor substrate is intrinsic; wherein the absorption region comprises a stepped profile or a tapered profile in a direction that is approximately parallel with a direction that the photodetector is to receive incident light from the waveguide.
However, in analogous art, Cohen discloses, the semiconductor substrate is intrinsic (intrinsic or undoped; [0039]);
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 Assefa and Cohen before him/her, to modify the teachings of a photodetector device as taught by Assefa and to include the teachings of the semiconductor substrate being intrinsic as taught by Cohen since in MPEP 2143 (I) (A), it is stated that Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Assefa, a person with ordinary skill in the art would be motivated to reach out to Cohen while forming a photodetector device of Assefa.
But the combination of Assefa and Cohen fails to teach explicitly, wherein the absorption region comprises a stepped profile or a tapered profile in a direction that is approximately parallel with a direction that the photodetector is to receive incident light from the waveguide.
However, in analogous art, Wu discloses, wherein the absorption region (300; absorption region; Fig. 3; [0043]) comprises a stepped profile or a tapered profile (tapered profile) in a direction that is approximately parallel with a direction (horizontal) that the photodetector (as annotated on Fig. 3) is to receive incident light from the waveguide (200; waveguide; Fig. 3; [0047]).
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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 Assefa, Cohen and Wu before him/her, to modify the teachings of a photodetector device as taught by Assefa and to include the teachings of an absorption region comprising a tapered profile as taught by Wu since in MPEP 2143 (I) (A), it is stated that Combining prior art elements according to known methods to yield predictable results is obvious. Absent this important teaching in Assefa, a person with ordinary skill in the art would be motivated to reach out to Wu while forming a photodetector device of Assefa.
Allowable Subject Matter
Claims 2-7, 10-14 and 22-26 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 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 1, wherein the absorption region comprises the stepped profile, and the stepped profile comprises a plurality of sections of increasing depth in the direction from which the photodetector is to receive the incident light”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 5, the closest prior art, US 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 1, wherein the absorption region is a first absorption region configured to absorb photons of a first wavelength range of the incident light; and wherein the photodetector further comprises a second absorption region configured to absorb photons of a second wavelength range of the incident light, wherein the first type doped collection region and the second type doped collection region are electrically coupled with the first absorption region and the second absorption region”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 7, the closest prior art, US 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 1, wherein the absorption region is a first absorption region configured to absorb photons of a first wavelength range of the incident light; wherein the first type doped collection region and the second type doped collection region are electrically coupled with the first absorption region; and wherein the photodetector further comprises: a third type doped collection region in the intrinsic semiconductor substrate; a fourth type doped collection region in the intrinsic semiconductor substrate; and a second absorption region, in the intrinsic semiconductor substrate between the third type doped collection region and the fourth type doped collection region, configured to absorb photons of a second wavelength range of the incident light, wherein the third type doped collection region and the fourth type doped collection region are electrically coupled with the second absorption region”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 10, the closest prior art, US 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 9, wherein the sloped section is located between a first flat-bottomed section and a second flat-bottomed section in the direction that the photodetector is to receive the incident light”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 11, the closest prior art, US 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 8, wherein the absorption region is a first absorption region configured to absorb photons of a first wavelength range of the incident light; and wherein the photodetector further comprises a second absorption region configured to absorb photons of a second wavelength range of the incident light, wherein the first absorption region and the second absorption region are adjacent in the direction that the photodetector is to receive the incident light, and wherein the first type doped collection region and the second type doped collection region are electrically coupled with the first absorption region and the second absorption region”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 13, the closest prior art, US 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 8, wherein the absorption region is a first absorption region configured to absorb photons of a first wavelength range of the incident light; wherein the first type doped collection region and the second type doped collection region are electrically coupled with the first absorption region; and wherein the photodetector further comprises: a third type doped collection region in the intrinsic semiconductor substrate; a fourth type doped collection region in the intrinsic semiconductor substrate; and a second absorption region, in the intrinsic semiconductor substrate between the third type doped collection region and the fourth type doped collection region, configured to absorb photons of a second wavelength range of the incident light, wherein the first absorption region and the second absorption region are adjacent in the direction that the photodetector is to receive the incident light, wherein the second absorption region comprises another tapered profile, and wherein the third type doped collection region and the fourth type doped collection region are electrically coupled with the second absorption region”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 22, the closest prior art, US 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 21, wherein the absorption region comprises the stepped profile, and the stepped profile comprises a plurality of sections of increasing depth in a direction from which the photodetector is to receive incident light”, in combination with the additionally claimed features, as are claimed by the Applicant.
Regarding claim 26, the closest prior art, US 2010/0038736 A1 (Assefa), in combination with US 2009/0289320 A1 (Cohen) and US 2025/0048749 A1 (Wu), fails to disclose, “the photodetector device of claim 21, wherein the absorption region comprises the tapered profile, and wherein the absorption region comprises a sloped section between a first flat-bottomed section and a second flat-bottomed section in a direction from which the photodetector is to receive incident light”, in combination with the additionally claimed features, as are claimed by the Applicant.
Claims 3-4, 6, 12, 14 and 22-25 are also objected to due to their 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 2019/0162519 A1 (Huang) - A photodetector is provided including an interferometer and a photodetection region coupled to the interferometer. The interferometer is configured to generate an optical intensity distribution that corresponds to an electric field distribution in the photodetection region.
US 2015/0108327 A1 (Huang) - A photodetector device is disclosed including a first region, a multiplication region, a second region, and an absorption region. The first region is associated with a first terminal, and the second region is associated with a second terminal. The first region is separated from the second region by the multiplication region. The absorption region is disposed on the multiplication region and associated with a third terminal. A multiplication region electric field is independently controllable with respect to an absorption region electric field, based on the first terminal, the second terminal, and the third terminal.
US 2006/0251375 A1 (Morse) - A semiconductor waveguide based optical receiver is disclosed. An apparatus according to aspects of the present invention includes an absorption region defined along an optical waveguide. The absorption region includes a first type of semiconductor material having a first refractive index. The apparatus also includes a multiplication region defined along the optical waveguide. The multiplication region is proximate to and separate from the absorption region. The multiplication region includes a second type of semiconductor material having a second refractive index. The first refractive index greater than the second refractive index such that an optical beam directed through the optical waveguide is pulled towards the absorption region from the multiplication region and absorbed in the absorption region to create electron-hole pairs from the optical beam. The multiplication region includes first and second doped regions defined along the optical waveguide. The first and second doped regions have opposite polarity to create an electric field to multiply the electrons created in the absorption region.
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
03/10/2026