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 .
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.
Claims 1-7 and 11-18 are rejected under 35 U.S.C. 103 as being unpatentable over Manda et al. (US 2019/0081191) (“Manda”) in view of Bui (US 2015/0171256).
With regard to claim 1, fig. 1B of Manda discloses a photoelectric conversion element 10B comprising: a first compound semiconductor layer 31 including a first compound semiconductor material 31 having a first conductivity type (“first compound semiconductor layer 31 made of a first compound semiconductor material having a first conductivity type”, par [0181]); a photoelectric conversion layer 34 formed in contact with the first compound semiconductor layer 31; a second compound semiconductor layer 32 formed in contact with the photoelectric conversion layer 31 and including a second compound semiconductor material (“second compound semiconductor layer 32 covering the photoelectric conversion layer 34 and made of a second compound semiconductor material “, par [0183]) having the first conductivity type (“first conductivity type”, par [0183]); a first second conductivity type region 35 formed on at least a part of the second compound semiconductor layer 32, having a second conductivity type (“second conductivity type region 35”, par [0184]) different from the first conductivity type (“first conductivity type”, par [0183]), and reaching the photoelectric conversion layer 34.
Manda does not disclose a second second conductivity type region formed on at least a part of the second compound semiconductor layer, having the second conductivity type, and reaching the photoelectric conversion layer, the second second conductivity type region having a region different from the first second conductivity type region.
However, fig. 1 of Bui discloses a second second conductivity type region 112, having the second conductivity type (p+), and reaching the photoelectric conversion layer 104, the second second conductivity type region 112 having a region different from the first second conductivity type region 110.
Therefore, it would have been obvious to one ordinary skill in the art to form the second conductivity type region of Manda with the lightly-doped P zone underneath a P+ layer in order to move the shallow junction to a deeper junction below the photodiode surface and provide an improved device with improved ruggedness, that is less prone to degradation, and has an improved linear current. See abstract of Bui.
With regard to claim 2, fig. 1B of Manda discloses a first electrode 52 electrically connected to the first compound semiconductor layer 31.
Manda does not disclose a second electrode formed on the second conductivity type regions.
However, fig. 1 of Bui discloses a second electrode 116 formed on the second conductivity type regions 112.
Therefore, it would have been obvious to one ordinary skill in the art to form the second conductivity type region of Manda with the lightly-doped P zone underneath a P+ layer in order to move the shallow junction to a deeper junction below the photodiode surface and provide an improved device with improved ruggedness, that is less prone to degradation, and has an improved linear current. See abstract of Bui.
With regard to claim 3, Manda does not disclose that the first second conductivity type region and the second second conductivity type region have different impurity concentrations.
However, fig. 1 of Bui discloses that the first second conductivity type region 110 and the second second conductivity type region 112 have different impurity concentrations (P+, P).
Therefore, it would have been obvious to one ordinary skill in the art to form the second conductivity type region of Manda with the lightly-doped P zone underneath a P+ layer in order to move the shallow junction to a deeper junction below the photodiode surface and provide an improved device with improved ruggedness, that is less prone to degradation, and has an improved linear current. See abstract of Bui.
With regard to claim 4, fig. 1B of Manda disclose and the first second conductivity type region 35 is formed closer to the first compound semiconductor layer 32 than the second second conductivity type region 31.
Manda does not disclose that the first second conductivity type region has a lower impurity concentration than the second second conductivity type region,
However, fig. 1 of Bui discloses that the first second conductivity type region 110 has a lower impurity concentration (p) than the second second conductivity type region 112.
Therefore, it would have been obvious to one ordinary skill in the art to form the second conductivity type region of Manda with the lightly-doped P zone underneath a P+ layer in order to move the shallow junction to a deeper junction below the photodiode surface and provide an improved device with improved ruggedness, that is less prone to degradation, and has an improved linear current. See abstract of Bui.
With regard to claim 5, Manda does not disclose a third second conductivity type region formed on at least a part of the second compound semiconductor layer, having the second conductivity type, and reaching the photoelectric conversion layer, the third second conductivity type region having a region different from the first second conductivity type region and the second second conductivity type region.
However, fig. 1 of Bui discloses a third second conductivity type region (“p+ doped rings 114”, par [0086]), having the second conductivity type (p), and reaching the photoelectric conversion layer 104, the third second conductivity type region 114 having a region different from the first second conductivity type region 110 and the second second conductivity type region 112.
Therefore, it would have been obvious to one of ordinary skill in the art to form the photoelectric conversion element of Manda with the p+ doped rings as taught in Bui in order to act as a guard ring to manage electric field, reduce dark current, and improve breakdown voltage. See par [0086] and [0103] of Bui.
With regard to claim 6, Manda does not disclose that the first second conductivity type region and the second second conductivity type region are formed by diffusing impurities under different conditions.
However, fig. 1B of Bui discloses that the first second conductivity type region 110 and the second second conductivity type region 112 are formed by diffusing impurities under different conditions (different concentration).
Therefore, it would have been obvious to one of ordinary skill in the art to form the photoelectric conversion element of Manda with the p+ doped rings as taught in Bui in order to act as a guard ring to manage electric field, reduce dark current, and improve breakdown voltage. See par [0086] and [0103] of Bui.
With regard to claim 7, Manda does not disclose that the first second conductivity type region and the second second conductivity type region are formed by diffusing the impurities from different positions.
However, fig. 1 of Bui discloses that the first second conductivity type region 110 and the second second conductivity type region 114 are formed by diffusing the impurities from different positions.
Therefore, it would have been obvious to one of ordinary skill in the art to form the photoelectric conversion element of Manda with the p+ doped rings as taught in Bui in order to act as a guard ring to manage electric field, reduce dark current, and improve breakdown voltage. See par [0086] and [0103] of Bui.
With regard to claim 11, fig. 1B of Manda discloses that the first electrode 52 is formed on a surface of the first compound semiconductor layer 31 on a light incident side (“light incident side”, par [0164]).
With regard to claim 12, fig. 1B of Manda discloses that the first compound semiconductor layer 31 and the second compound semiconductor layer 32 include a same material (“InP, par [0190]).
With regard to claim 13, fig. 1B of Manda discloses that the first compound semiconductor layer 31 and the second compound semiconductor layer 32 include a group III-V compound semiconductor material (“InP, par [0190]).
With regard to claim 14, fig. 1B of Manda discloses that the photoelectric conversion layer includes InGaAs (“photoelectric conversion layer 34 is made of InGaAs”, par [0190]), and the first compound semiconductor layer 31 and the second compound semiconductor layer 32 include InP (“InP, par [0190]).
With regard to claim 15, fig. 1B of Manda discloses that light (“light incident side”, par [0164]) enters through the first compound semiconductor layer 31.
With regard to claim 16, fig. 1B of Manda discloses that an imaging device in which a plurality of the photoelectric conversion elements 10A is arranged in a two-dimensional matrix (“two dimensional matrix form”, par [0189]).
With regard to claim 17, fig. 1B of Manda discloses that a method for manufacturing a photoelectric conversion element 10B comprising the steps of: sequentially forming a first compound semiconductor layer 31 including a first compound semiconductor material (“first compound semiconductor material”, par [0181]) having a first conductivity type (“first conductivity type”, par [0181]), a photoelectric conversion layer 34, and a second compound semiconductor layer 32 including a second compound semiconductor material 32 having the first conductivity type (“first conductivity type”, par [0183]); forming, on at least a part of the second compound semiconductor layer 32, a first second conductivity type region 35 having a second conductivity type (“second conductivity type region 35”, par [0184]) different from the first conductivity type (“first conductivity type”, par [0183]) and reaching the photoelectric conversion layer 34, forming, on at least a part of the second compound semiconductor layer 32.
Manda does not disclose a second second conductivity type region having the second conductivity type and reaching the photoelectric conversion layer under a condition different from a condition of the first second conductivity type region.
However, fig. 1 of Bui discloses a second second conductivity type region having the second conductivity type 112 and reaching the photoelectric conversion layer 104 under a condition different (P+ vs P) from a condition of the first second conductivity type region 110.
Therefore, it would have been obvious to one ordinary skill in the art to form the second conductivity type region of Manda with the lightly-doped P zone underneath a P+ layer in order to move the shallow junction to a deeper junction below the photodiode surface and provide an improved device with improved ruggedness, that is less prone to degradation, and has an improved linear current. See abstract of Bui.
With regard to claim 18, fig. 1B of Manda disclose that the first second conductivity type region 35 are formed by diffusing impurities from the second compound semiconductor layer 32 via a mask layer (“mask layer”, par [0231]).
Manda does not disclose the second second conductivity type region are formed by diffusing impurities via a mask layer.
However, fig. 1 of Bui discloses that the first second conductivity type region 110 and the second second conductivity type region 112 are formed by diffusing impurities via a mask layer (“oxide layers”, par [0104]).
Therefore, it would have been obvious to one ordinary skill in the art to form the second conductivity type region of Manda with the lightly-doped P zone underneath a P+ layer in order to move the shallow junction to a deeper junction below the photodiode surface and provide an improved device with improved ruggedness, that is less prone to degradation, and has an improved linear current. See abstract of Bui.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Manda et al. (US 2019/0081191) (“Manda”), Bui (US 2015/0171256), and Kusakabe (JP 05-160426).
With regard to claim 10, Manda and Bui do not disclose that the photoelectric conversion layer is formed by laminating a plurality of layers having different impurity concentrations.
However, fig. 1 of Kusakabe discloses that the photoelectric conversion layer (5, 4) is formed by laminating a plurality of layers having different impurity concentrations (“n+ InGaAs light-absorbing layer 4 doped with a Group IV element preferably having a 2E15cm^-3 concentration”, “5 preferably having a 1e15cm^-3 concentration”, par [0010]).
Therefore, it would have been obvious to one of ordinary skill in the art to form the second conductivity type region of Manda with different concentration regions as taught in Kusakabe in order to improve the high-speed response in combination with the suppression of the space charge effect. See par [0017] of Kusakabe.
Allowable Subject Matter
Claims 8-9 and 19-20 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
With regard to claim 1, figs. 1 and 3 of Shiba (US 5,010,381) discloses a photoelectric conversion element (“semiconductor light detector”, col. 3 ll. 12-13) comprising: a first compound semiconductor layer 8 including a first compound semiconductor material (“n-type InP substrate 8”, col. 3 ll. 18-19) having a first conductivity type (“n-type”, col. 3 ll. 18); a photoelectric conversion layer (7, 6) formed in contact with the first compound semiconductor layer 8; a second compound semiconductor layer 5 formed in contact with the photoelectric conversion layer (7, 6) and including a second compound semiconductor material 5 having the first conductivity type (“n-type”, col. 3 ll. 18); a first second conductivity type region 11 formed on at least a part of the second compound semiconductor layer 5, having a second conductivity type (“second p-type region 11”, col. 3 ll. 32) different from the first conductivity type (“n-type”, col. 3 ll. 18), and reaching the photoelectric conversion layer (6, 7); and a second second conductivity type region 10 formed on at least a part of the second compound semiconductor layer 5, having the second conductivity type (“p-type”, col. 3ll. 25), and reaching the photoelectric conversion layer (6, 7), the second second conductivity type region 10 having a region different from the first second conductivity type region 11.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BENJAMIN T LIU whose telephone number is (571)272-6009. The examiner can normally be reached Monday-Friday 11:00am-7:30pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Yara J Green can be reached at 571 270-3035. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/BENJAMIN TZU-HUNG LIU/ Primary Examiner, Art Unit 2893