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 .
Claim Rejections - 35 USC § 112
Claim 25 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 25, this claim recites the phrases of “an upper surface” and “a recess surface”. However, it is unclear what exactly these surfaces refer to. More specifically, an upper surface and a recess surface of what? Clarification is required.
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(s) 1-3, 5, 10 and 25 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hsu et al (US 9,991,303) in view of Huang et al (US 2020/0098813).
Regarding claim 1, Hsu et al shows in Figs.1-2 the following elements of applicant’s claim: a substrate (102) having a frontside (102a) and a backside (102b) opposite the frontside; a plurality of image-sensing elements (130R, 130G, 130B) arranged within the substrate; a trench isolation structure (col.3, lines 13-17) disposed between adjacent image-sensing elements, extending from the backside of the substrate to a first depth within the substrate and laterally surrounding the plurality of image-sensing elements; a light transmission layer (106) formed over the backside of the substrate, the light transmission layer comprising a first side (a top side of 106), a second side (a bottom side of 106) opposite the first side, the second said adjacent to the backside of the substrate (Fig.2); and a buried grid structure (Figs.2, 3A-3F) in the light transmission layer (106), the buried grid structure extending from the first side (a top side of 106) of the light transmission layer. While Hus et al discloses in col.3, lines 13-17 the use of shallow trench isolation (STI), it does not specifically mention the use of deep trench isolation (DTI). However, the use of a DTI structure or a STI structure in an image sensor is well known in the art as disclosed by Huang et al (paragraph 42) and such use in the device of Hsu et al would have been obvious to one of ordinary skill in the art in view of the desire to meet different design requirements and to reduce leakage currents between the image sensing elements resulting in improving the performance of the image sensor device. Regarding the feature of the buried grid structure being offset to the DTI structure along a first direction and the upper grid structure is offset to the DTI structure along a second direction, such feature is known in the art as disclosed in Huang et al (in view of a region 304 in Fig.3, buried grid structure 116 is offset to DTI structure 110; and upper grid structure 120 is offset to DTI structure 110) and it would have been obvious to one of ordinary skill in the art to utilize the teachings of Huang et al in the device of Hsu et al in view of the desire to further improve the quantum efficiency resulting in further improving the image sensor device.
Regarding claims 2-3, although Hsu does not specifically mention the use of a metal nitride layer for the buried grid structure, such use is well known in the art and would have been obvious to one of ordinary skill in the art in view of the desire to provide a barrier layer resulting in further reducing crosstalk between the image sensing elements.
Regarding claim 5, the specific arrangement utilized for the upper grid structure and the buried grid structure would have been obvious to one of ordinary skill in the art in view of meeting different design requirements and involving only routine skill in the art.
Regarding claim 10, the limitations therein are shown in Figs.1-2 of Hsu.
Regarding claim 25, as far as the claim is understood, the specific configuration utilized for the buried grid structure would have been an obvious design choice to one of ordinary skill in the art depending on the needs of particular application.
Allowable Subject Matter
Claims 11-24 are allowed.
The following is a statement of reasons for the indication of allowable subject matter: Regarding claims 11-15 and 21-22, in view of applicant’s argument set forth in the amendment filed on 2/10/2026, it is agreed that the prior art fails to disclose or make obvious an optical structure comprising, in addition to the recited features of a substrate, a plurality of image-sensing elements, an isolation structure, a light transmission layer, a buried grid structure and an upper gird structure, the limitation of “the light transmission layer and buried grid structure have a plurality of recess portions, and the upper grid structure sections surround the plurality of recess portions”. Regarding claims 16-20 and 23-24, in view of applicant’s argument set forth in the amendment filed on 2/10/2026, it is agreed that the prior art fails to disclose or make obvious a method of forming an optical structure comprising, in addition to the other recited features of claim 16, the limitation of “removing a portion of the buried grid structure to form a notch in the buried grid structure”.
Applicant's arguments filed on 2/10/2026 have been fully considered but they are not persuasive.
Regarding claim 1, applicant argues that Hsu in view of Huang doesn’t disclose that an optical device including a buried grid structure being offset relative to a DTI structure along a first direction and an upper grid structure offset relative to the DTI along a second direction. However, the examiner disagrees with this argument. Contrary to applicant’s argument, Huang shows in Fig.3 (in view of a region 304 in Fig.3) a buried grid structure 116 is offset to a DTI structure 110 and an upper grid structure 120 is offset to the DTI structure 110. As explained in the rejection above, while neither reference discloses all the claimed limitations singularly, Hsu recites a number of them and the remaining elements are taught by Huang. It should be noted that the test of obviousness is whether the combined teaching of the references would have suggested the combination to one of ordinary skill in the art, not whether each reference individually meets the each claimed limitation.
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/KEVIN K PYO/Primary Examiner, Art Unit 2878