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 .
Response to Amendment
Applicant’s Amendment filed February 5, 2026 has been fully considered and entered.
Election/Restrictions
As summarized in the Office action mailed on December 1, 2025, Applicant elected Invention I (a photodiode), Species A-2 (geometry of the absorption region is non-rectangular / non-linear), B-2 (geometry of the first portion of the absorption region is non-rectangular / non-linear clipped tapered geometry), C-1 (the absorption region is centered with respect to the optical coupler) in the reply filed on September 26, 2025 without traverse.
Claims 4-6, 8, and 12-25 are withdrawn from further consideration as being drawing to a nonelected invention and/or species.
The examiner notes that claim 1 has been amended by broadening the claim, wherein the absorption region is no longer required to have a non-rectangular geometry, thus claim 1 appears to be a generic claim as amended.
Newly amended claim 10, previously examined, has been amended to read on non-elected species B-1 (the geometry of the first portion of the absorption region is rectangular).
Therefore, claim 10 is withdrawn from further consideration as being direction to a non-elected species.
Response to Arguments
Applicant's arguments filed February 5, 2026 have been fully considered but they are not persuasive.
Applicant has amended claim 1 to include a clarification that the “wherein the first portion or an optical waveguide uses a geometry enabling the absorption region to convert a constant amount of photons to electrical energy at each unit of absorption region length” and points to paragraphs 22, 23, 32, 43, 46, 50, and 63-65, Figures 10A and 10B, and original claim 10 for support.
As an initial point, paragraphs 63-65 and Figures 10A-10B are directed to a non-elected specie A-1, B-1 in which the absorption region has a rectangular geometry. Claim 1 has been broadened to read on the non-elected species, and therefore, claim 1 is considered generic, but the non-elected species has not been examined.
Paragraph 22 explains that (emphasis added) “It would be beneficial to have a linear decay of the optical signal with a constant proportion of photons being converted to electrons at each propagation distance.”
Paragraph 23 explains that (emphasis added) “[a]s the absorption curve approaches linearization there is a more uniform absorption throughout the absorption region.”
Paragraph 32 states that (emphasis added) “[i]n some aspects, the portion of the absorption region utilizes a non-rectangular geometry that is a non-linear geometry while enabling a linear or near linear transmission signal absorption profile. For example, FIGS. 4, 6, and 9 demonstrate some potential non-linear geometry shapes for the portion of the absorption region facing the optical signal.”
Paragraph 49 states that (emphasis added) “chart 430 demonstrates the absorption curve for each type of absorption region. Chart 430 has an x-axis 435 of the propagation length and a y-axis 436 of the remaining optical power. Chart 430 demonstrates that conventional absorption region 410 can result in an absorption curve that resembles curve 440. The amount of optical power able to be absorbed drops quickly over the propagation distance. Clipped tapered absorption region 420 can result in an absorption curve that resembles curve 445. Curve 445 shows that the absorption curve is close to being linear over the propagation distance. This can lead to improvement in gain and bandwidth saturation at higher optical powers, thereby allowing a higher rate of transmission of the optical signal.”
Paragraph 50 explains that (emphasis added) “FIG. 5 is an illustration of a diagram of an example optical signal absorption 500 varying with the Si and Ge proportions. Optical signal absorption 500 demonstrates a sample absorption pattern using Ge as the absorption region and where the absorption region utilizes a clipped tapered geometry, such as clipped tapered absorption region 420. Optical signal absorption 500 has an x-axis 505 of the Si width in micrometers, a y-axis 506 of the Ge width in micrometers, and a z-axis 507 of the absorption length in micrometers.
Therefore, paragraphs 49 and 50, clearly establish that the clipped tapered geometry of absorption region 420 (see Figure 4) provides the claimed function of “enabling the absorption region to convert a constant amount of photons to electrical energy at each unit of absorption region length” in the present invention. Thus, based on Applicant’s disclosure, it is the clipped tapered geometry of the elected species that provides the newly claimed function of enabling the absorption region to convert a constant amount of photons to electrical energy at each unit of absorption region length. The examiner cannot find any teachings to suggest that all clipped tapered geometries would not perform in this manner.
Applicant states that “Kang does not appear to teach that a constant amount of absorption of photons is enabled by the geometry of the absorption region or the optical waveguide. It appears Kang focuses on other aspects of the diode. It appears that Kang specifies different criteria for the amount of optical signal coupled to the light absorbing layer. One criteria is that the amount of optical signal "may vary according to the length of the photodiode of the optical waveguide with a fixed width" (see Kang paragraph [0042]. Kang appears to specify that the optical signal varies. Amended Claim 1 specifies that there is a constant proportion of photons being absorbed. These are two different aspects of the PD, the light coming in versus the light being absorbed.
The examiner disagrees.
As explained above, the clipped tapered geometry of the absorption region of the present invention provides the function of enabling the absorption region to convert a constant amount of photons to electrical energy at each unit of absorption region length. Kang discloses that the absorption region (20-2) utilizes a clipped tapered geometry (see Figure 3).
Applicant further states that it appears that Kang requires a ratio between the thickness of the core layer and the absorption layer. Claim 1 does not require a relationship between a core layer for its absorption calculation. Claim 1 uses only the absorption region or the optical waveguide geometry.
The examiner disagrees.
The present invention provides an absorption region having a clipped tapered geometry that provides the function of enabling the absorption region to convert a constant amount of photons to electrical energy at each unit of absorption region length, as discussed above. Kang discloses that the absorption region (20-1) utilizes a clipped tapered geometry (see Figure 3 of Kang).
The examiner notes that the claim 1 uses the transition term “comprising”. The translation term “comprising”, which is synonymous with “including”, “containing”, or “characterized by,” is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. Moleculon Research Corp. v. CBS, Inc., 793 F.2d 1261, 229 USPQ 805 (Fed. Cir. 1986) In re Baxter, 656 F.2d 679, 210 USPQ 795, 803 (CCPA 1981); Ex parte Davis, 80 USPQ 448, 450 (Bd. App. 1948) (“comprising” leaves “the claim open for the inclusion of unspecified ingredients even in major amounts”). Thus the language of claim 1 does not prohibit a thickness variation of the absorption layer.
Paragraph 32 of the present specification states that “[t]he absorption region has an absorption coefficient that can vary along the non-rectangular portion of the absorption region (e.g., the non-rectangular region varies in thickness as the geometry varies).” Thus, although not claimed, the specification discloses that the thickness of the absorption layer may vary, and a ratio between the thickness of the core layer and the absorption layer would inherently vary as a result.
Applicant additionally states that it appears that Kang merely states that "the amount of optical signal launched into the photodiode increases" (see Kang paragraph [0042]). In amended Claim 1, the amount of optical signal launched is immaterial, as the calculations use the geometry of the absorption region or the geometry of the optical waveguide regardless to the amount of optical signal launched. Kang does not specify a constant amount of photon absorption.
The examiner disagrees.
Again, the examiner asserts that the present specification discloses that the clipped tapered geometry of the absorption region provides the claimed function. Kang discloses the clipped tapered geometry of the absorption region.
Applicant states that “[a]s the Office is no doubt aware, anticipation requires that each and every element of the claimed invention be disclosed in a single prior art reference; the disclosed elements must either be disclosed expressly or inherently and must be arranged as in the rejected claims.”
Applicant has amendment claim 1 to state that “the absorption region has a first portion capable of receiving the optical signal, and wherein the first portion or an optical waveguide uses a geometry enabling the absorption region to convert a constant amount of photons to electrical energy at each unit of the absorption region length.”
As discussed above, an absorption region having a first portion that has a clipped tapered geometry is capable of receiving the optical signal, and the clipped tapered geometry enables the absorption region to convert a constant amount of photons to electrical energy at each unit of the absorption region length. Please see paragraphs 23, 32, 49 and 50 of the present application.
Kang discloses an absorption region having a first portion with a clipped tapered geometry.
Claim Rejections - 35 USC § 102
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 (i.e., changing from AIA to pre-AIA ) 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 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.
Claims 1-3, 7, 9, and 11 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kang et al. (US 2016/0216446 A1).
Regarding claims 1-3, 7, 9, and 11; Kang et al. discloses a photodiode (PD) (photodiode 30-2; see Figure 3), comprising:
an optical coupler (see annotated Figure 3 below; the end-face of the waveguide 10 that receives light is an optical coupler) configured to receive an optical signal; and
an absorption region (light absorbing layer 20-2), configured to receive the optical signal from the optical coupler and convert the optical signal to an electrical signal (see paragraph 24), the absorption region (20-2) has a first portion capable of receiving the optical signal, and wherein the first portion or an optical waveguide uses a geometry (clipped tapered geometry of absorption region 20-2 illustrated in Figure 3) enabling the absorption region to convert a constant amount of photons to electrical energy at each unit of the absorption region length (absorption regions having clipped tapered geometries enable conversion of a constant amount of photons to electrical energy at each unit of the absorption region length, as described in paragraphs 23, 32, 49, and 50 of the present specification);
wherein the absorption region (20-2) utilizes a non-rectangular geometry (clipped tapered geometry; see Figure 3 of Kang) and the optical waveguide utilizes a rectangular geometry (see Figure 3 of Kang);
wherein the first portion of the absorption region (20-2) utilizes a clipped tapered geometry (see Figure 3);
wherein the first portion of the absorption region (20-2) is centered with respect to the optical coupler (input end of waveguide 10; see Figure 3);
wherein an absorption coefficient of the absorption region satisfies
α
z
=
1
-
β
L
-
1
-
β
Z
(this is inherent to the disclosed structure, since absorption coefficients are determined by the material and structure, and the disclosed structure meets all of the claimed structural limitations; 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). MPEP 2112.01 (I)), thus, the absorption coefficient, (
α
z
)
, of the first portion satisfies a numerator of one minus a fraction of an original incident power after a propagation distance along the absorption region length, (1-β), divided by a denominator of the propagation distance, L, minus a value equal to the numerator, (1-β), times a position along the absorption region length, z, where β is the desired fraction of the original incident power after a propagating distance L along the absorption region and z is the position along the length of the absorption region); and
wherein the PD is one of an avalanche PD (APD), a waveguide integrated APD (WGAPD), or a waveguide integrated PD (WGPD) (see Figure 3, wherein a waveguide integrated photodiode is illustrated).
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 MICHELLE R CONNELLY whose telephone number is (571)272-2345. The examiner can normally be reached Monday-Friday, 9 AM to 5 PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Uyen-Chau Le can be reached at 571-272-2397. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MICHELLE R CONNELLY/Primary Examiner, Art Unit 2874