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 .
Election/Restrictions
Applicant’s election without traverse of Species A1, B1, C1, and D1 in the reply filed on 8/8/2025 is acknowledged. Applicant has canceled claims directed to the unelected species thereby rendering the restriction moot, as such the restriction requirement is withdrawn.
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 (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 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.
The factual inquiries 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(s) 1, 2, and 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kuntzman et al. (US 2020/0112799 A1) in view of Grosh et al. (US 2015/0350792 A1).
Regarding claim 1, Kuntzman discloses a method of fabricating a die for a microelectromechanical systems (MEMS) microphone, the method comprising:
forming a diaphragm (“second diaphragm 330” in Fig. 3C, ¶ 0052);
etching a plurality of slots through the diaphragm (“openings 339, 339a may be defined in the second diaphragm 330, 330a via a wet etch or dry etch process”, ¶ 0091) to define a plurality of springs (flat portions of the diaphragm 330 between adjacent slots 339, Fig. 3A); and
sealing the plurality of slots a sealing material (“a plug 364 of a sealing material” in Fig. 3C, ¶ 0065), thereby disabling the springs;
wherein the sealing material comprises a first material (“low stress silicon nitride”, ¶ 0065) and the diaphragm is formed of a second material (“polysilicon layer”, ¶ 0061).
Kuntzman does not disclose releasing the diaphragm and the plurality of springs, wherein the plurality of springs relieves intrinsic stress of the diaphragm.
Grosh, in the same field of endeavor, releasing a diaphragm layer to relieve intrinsic stress of the diaphragm (“the diaphragm then being micromachined or otherwise processed to substantially detach it from the substrate so that the layers can expand or contract as necessary to relieve any residual stress”, ¶ 0118). There was a benefit to relieving the stress as stress in the diaphragm layer reduces output energy (¶ 0050 of Grosh). It would have been obvious to one having ordinary skill in the art before the Application's effective filing date to release the diaphragm layer of Kuntzman (which includes the plurality of springs such that the springs also relieve intrinsic stress of the diaphragm) for this benefit.
Regarding claim 2, Kuntzman in view of Grosh further discloses that the forming step comprises forming the diaphragm over a substrate (“substrate 312” in Fig. 3A, ¶ 0059 of Kurtzman); and
further comprising, before the releasing step in the method of the combination, etching away a first portion of the substrate (opening 313 shown in Fig. 3A) underlying the plurality of springs such that the diaphragm has a first region overlying the first portion and not anchored to the substrate (see Fig. 3A of Kuntzman) and a second region that is anchored to a second portion of the substrate (see Fig. 3A);
wherein the plurality of springs is disposed within the first region proximate to a boundary between the first and second regions (see Fig. 3A); and
wherein the first region is movable in response to pressure waves during operation of the MEMS microphone (the diaphragm vibrates during usage, ¶ 0063 of Kuntzman).
Regarding claim 5, Kuntzman in view of Grosh further discloses after the forming step and before the etching step, forming a rigid element (“back plate 340” in Fig. 3A, ¶ 0052) parallel to and spaced apart from the diaphragm;
wherein the diaphragm comprises a first electrode (“second conductive layer”, ¶ 0061), and the rigid element comprises a second electrode (“back plate 340”, ¶ 0052).
Allowable Subject Matter
Claims 6, and 8-12 are allowed.
The following is an examiner’s statement of reasons for allowance:
Claim 6 is directed to a method of fabricating a die for a microelectromechanical systems (MEMS) microphone, the method comprising: forming an assembly comprising a first diaphragm, a second diaphragm parallel to and spaced apart from the first diaphragm, and a rigid central layer disposed between the first and second diaphragms; etching a first plurality of slots through an outer region of the first diaphragm to define a first plurality of springs; etching a second plurality of slots through an outer region of the second diaphragm to define a second plurality of springs; releasing the assembly, wherein the first plurality of springs relieves intrinsic stress of the first diaphragm and the second plurality of springs relieves intrinsic stress of the second diaphragm; and sealing the first and second pluralities of slots with sealing material, thereby disabling the first and second pluralities of springs; and forming a sealed, low-pressure region between the first and second diaphragms.
Kuntzman et al. (US 2020/0112799 A1), the closest prior art of record, discloses a method of fabricating a die for a microelectromechanical systems microphone including a first and second diaphragm (330 and 320 in Fig. 3A) and further discloses etching a plurality of slots (339) through an outer region diaphragm 330 which are then sealed with a sealing material (364 in Fig. 3C). However, Kuntzman does not disclose etching and sealing a plurality of slots in diaphragm 320. Further, it would not have been obvious to one having ordinary skill in the art at the time the Application was filed to duplicate the slots into both diaphragms as Kuntzman discloses that the purpose of the slots is to pour etchant to reach a layer underlying diaphragm 330 (¶ 0065) and, therefore, there would not have been a benefit to duplicating the slots.
Claims 8-12 depend from claim 6 and are, therefore, also allowed.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRISTOPHER A CULBERT whose telephone number is (571)272-4893. The examiner can normally be reached M-F 9-5.
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, Joshua Benitez can be reached at (571) 270-1435. 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.
/CHRISTOPHER A CULBERT/ Examiner, Art Unit 2815