DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 02/10/2026 has been entered.
Claim Rejections - 35 USC § 103
The following is a quotation of pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived 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 pre-AIA 35 U.S.C. 103(a) 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 and 9 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Kim et al. (US 2006/0145207 A1) in view of Cha (US 2009/0286345 A1), Lee (US 2007/0052053 A1), and further in view of Toda (US 2008/0087800 A1).
Regarding claim 1, Kim et al. teach a process for making an optoelectronic device (image sensor; Abstract]), comprising: providing a substrate (P++-type substrate 40 and P-EPI 41; Fig. 3A, [0036]) made of a first material (silicon; [0026]); etching a region (47; Fig. 3B, [0041]) of the substrate (40 and 41); filling the region (47) with a second material (layer 49, which can be a SiGe layer; Fig. 3D, [0043-0044]) different from the first material (silicon); forming an N-well (the portion of 51 outside the pn junction formed at the interface of 50 and 51; Fig. 3D, [0049]) in the region made of the second material (49 of SiGe; Fig. 3D), by implantation ([0049]); forming a photo diode (50 and the pn junction formed at the interface of 50 and 51; Fig. 3D, [0049]) for a first wavelength (the wavelength of the SiGe photodiode) within the region made of the second material (49 of SiGe), wherein the N-well (the portion of 51 outside the pn junction formed at the interface of 50 and 51) isolates the photo diode (50 and the pn junction formed at the interface of 50 and 51) to block defect-induced dark current from the region made of the second material (49 of SiGe; Kim et al. teach the same N-well formed in the second material and would have the same function as blocking defect-induced dark current from the region made of the second material), an electronic circuit (the transistor of the transfer gate Tx; Fig. 3D, [0049]), wherein the electronic circuit (the transistor of the transfer gate Tx; Fig. 3D, [0049]) is coupled to the photo diode (50 and the pn junction formed at the interface of 50 and 51) for processing electronic signals (transferring photoelectrons; [0012]) generated when the photo diode (50 and the pn junction formed at the interface of 50 and 51) receives light (intrinsic property of the photo diode); wherein the second material (SiGe) includes silicon germanium (Si1-xGex) or silicon carbide (Si1-yCy), wherein 0 < x,y < 1 (SiGe, i.e. SixGe1-x, wherein 0 < x < 1); wherein the photo diode (50 and the pn junction formed at the interface of 50 and 51) comprises a P-well (50; Fig. 3D, [0049]) formed by ion implantation ([0066]) in the N-well (the portion of 51 outside the pn junction formed at the interface of 50 and 51), such that a PN junction (the pn junction formed at the interface of 50 and 51) is formed at an interface between the P-well (50) and the N-well (the portion of 51 outside the pn junction formed at the interface of 50 and 51); and wherein a portion of the N-well (the portion of 51 outside the pn junction formed at the interface of 50 and 51) outside the PN junction (the pn junction formed at the interface of 50 and 51) laterally surrounds the photo diode (50 and the pn junction formed at the interface of 50 and 51) and extends beneath a lower boundary of the photo diode (50 and the pn junction formed at the interface of 50 and 51), thereby isolating the photo diode (50 and the pn junction formed at the interface of 50 and 51) to block defect-induced dark current from the region made of the second material (49 of SiGe; Kim et al. teach the same N-well formed in the second material and would have the same function as blocking defect-induced dark current from the region made of the second material).
Kim et al. do not teach filling the region with a second material by epitaxial growth; and an interconnection is further formed above the photo diode to complete an integrated device including the photo diode and an electronic circuit, and forming another photodiode for a second wavelength in the substrate and not in the region made of the second material.
In the same field of endeavor of the image sensor, Cha teaches filling the region (a trench; [0037]) with a second material (SiGe; Fig. 3B, [0038]) by epitaxial growth (epitaxial layer 212; Fig. 3B, [0038]).
It would have been obvious to one of ordinary skill in the art at the time of invention was made to combine the inventions of Kim et al. and Cha, and to fill the second material of SiGe by epitaxial growth, because Kim et al. teach filling the second material of SiGe ([0043]), but is silent about how the SiGe layer is filled, while Cha teach that the SiGe layer (212; Fig. 3B, [0038]) can be filled up by epitaxial growth as indicated that the layer 212 filled is an epitaxial layer (212; Fig. 3B, [0038]).
In the same field of endeavor of image sensor, Lee teaches an interconnection (134; Fig. 1, [0040]) is further formed above the photo diode (102; Fig. 1, [0039]) to complete an integrated device (image sensor; Fig. 1, [0039]) including the photo diode (102) and an electronic circuit (transistors 104; Fig. 1, [0039]).
It would have been obvious to one of ordinary skill in the art at the time of invention was made to combine the inventions of Kim et al., Cha and Lee, and to further include the interconnection and the electronic circuit, because Lee teaches that the interconnection (134) and the electronic circuit (104) are key elements of the image sensor to couple the transistor and the photodiode ([0039-0040]).
In the same field of endeavor of photodiodes, Toda teaches forming another photodiode (photodiode of the visible light detecting pixel 12VL; Fig. 13, [0256], [0258]) for a second wavelength (visible light; [0256]) in the substrate (semiconductor device layer; Fig. 13) and not in the region made of the second material (the region of the photodiode of the infrared light detecting pixel 12IR being n type different from the p-well; Fig. 13, [0262]).
It would have been obvious to one of ordinary skill in the art at the time of invention was made to combine the inventions of Kim et al., Cha, Lee and Toda, and to incorporate the photodiode of Kim et al. into the solid-state image capturing device of Toda, because the solid-sate image capturing device of Toda use photodiodes to capture both visible light and infrared light as taught by Toda ([0003], [0258] and [0262]), while the photodiode of Kim et al. can prevent dark current from laterally transferring which improves the imaging quality of pixel structure as taught by Kim et al. ([0011, 0073]).
Regarding claim 2, Kim et al. teach the process of claim 1, further comprising: forming the electronic circuit (the transistor of the transfer gate Tx; Fig. 3D, [0027]) in another region of the substrate (the channel region of the transistor of the transfer gate Tx would be in 40 and 41 directly below Tx; [0049]).
Regarding claim 4, Kim et al. teach the process of claim 1, further comprising: forming a masking layer (45A/43A/42A; Fig. 3B, [0041]) to define the region (47) before etching the region (47; [0041]).
Regarding claim 5, Kim et al. teach the process of claim 4, further comprising: removing the masking layer (45A; Fig. 3C, [0044]) after filling the region with the second material (SiGe; [0043-0044]).
Regarding claim 6, Kim et al. teach the process of claim 4, wherein the masking layer (45A/43A/42A) includes oxide (45 of oxide; [0041]).
Regarding claim 9, Kim et al. teach the process of claim 1.
Kim et al. do not teach wherein the first wavelength is an invisible light wavelength and the second wavelength is a visible light wavelength.
In the same field of endeavor of photodiodes, Toda teaches, wherein the first wavelength is an invisible light wavelength (infrared of the infrared light detecting pixel 12IR; [0262]) and the second wavelength is a visible light wavelength (visible light; [0256]).
It would have been obvious to one of ordinary skill in the art at the time of invention was made to combine the inventions of Kim et al., Cha, Lee and Toda, and to incorporate the photodiode of Kim et al. into the solid-state image capturing device of Toda, because the solid-sate image capturing device of Toda use photodiodes to capture both visible light and infrared light as taught by Toda ([0003], [0258] and [0262]), while the photodiode of Kim et al. can prevent dark current from laterally transferring which improves the imaging quality of pixel structure as taught by Kim et al. ([0011, 0073]).
Claim 7 is rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Kim et al., Cha, Lee and Toda as applied to claim 1 above, and further in view of Hunt (US 2005/0279920).
Regarding claim 7, Kim et al. teach the photo diode (207 and the pn junction at the interface of 206/207 in Fig. 8).
Kim et al. do not teach wherein a light absorption efficiency of the photo diode to a light beam above 800 nm or below 450 nm is higher than a photo diode formed in silicon.
In the same field of endeavor of photodiodes, Hunt teach wherein a light absorption efficiency of the photo diode (a photodiode of SiC; [0023]) to a light beam above 800 nm or below 450 nm is higher than a photo diode formed in silicon (an intrinsic property of SiC).
It would have been obvious to one of ordinary skill in the art at the time of invention was made to combine the inventions of Kim et al., Cha, Lee, Toda and Hunt, and to use silicon carbide as the material of the photodiode as taught by Hunt, because SiC is one of the common materials to form the photodiode ([0023]).
Response to Arguments
Applicant's arguments with respect to claim 1 have been considered but are moot in view of the new ground(s) of rejection.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Noh (US 20060186442 A1) teach a method of making an image sensor having a photodiode inside a trench of a substrate.
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/HSIN YI HSIEH/Primary Examiner, Art Unit 2899 2/21/2026