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 .
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 allowance. 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, prosecution in this application has been reopened pursuant to 37 CFR 1.114. Applicant's submission filed on 1/12/2026 has been entered.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 1/12/2026 is in compliance with the provisions of 37 CFR 1.97 and being considered by the examiner.
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.
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.
Claims 11-19 are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Patent No. 10,491,192, issued Nov. 26, 2019 (“Plesski”), of record, in view of U.S. Patent Application Publication No. 2009/0231061 A1, published Sep. 17, 2009 (“Tanaka”).
Plesski discloses in Figs. 1-4 and the corresponding description:
PNG
media_image1.png
450
580
media_image1.png
Greyscale
Claims 11-14, 18-19
an acoustic wave device (Fig. 1, annotated, acoustic resonator 100, Abstract, 3:18-4:22) comprising:
a piezoelectric film made of lithium niobate or lithium tantalate (piezoelectric plate 110, 3:27-33);
a first busbar electrode and a second busbar electrode located on the piezoelectric film and opposite to each other (IDT busbars 132, 134, 3:60-61); and
a first electrode finger and a second electrode finger on the piezoelectric film, the first electrode finger including one end coupled to the first busbar electrode, the second electrode finger including one end coupled to the second busbar electrode (Fig. 1, IDT electrode fingers 136 coupled to busbars 132 and 134, 3:50-59); wherein
d/p is about 0.5 [claim 14: 0.24] or smaller, where d is a thickness of the piezoelectric film, and p is the center-to-center distance between the first electrode finger and the second electrode finger that are adjacent to each other. (Fig. 2, 4:64-67, “Dimension p is the center-to-center spacing or “pitch” of the IDT fingers, which may be referred to as the pitch of the IDT and/or the pitch of the XBAR.”; “p is typically between 2 to 20 times the thickness of the piezoelectric plate (5:8-10), that is, Plesski discloses d/p from 0.05 to 0.5, as required by the claims).
the first electrode finger and the second electrode finger extend in a first direction (Fig. 1, annotated, Y-axis), the first direction is perpendicular to a second direction (X-axis), the first electrode finger and the second electrode finger face each other in the second direction (X-axis) (Fig. 1, annotated, electrode fingers 136);
a first gap is provided between the first busbar electrode and the second electrode finger, and a second gap is provided between the second busbar electrode and the first electrode finger (Fig. 1, annotated, distance between electrode fingers 136 and busbars 132 and 134).
PNG
media_image2.png
200
400
media_image2.png
Greyscale
Fig. 2 of Plesski reproduced for ease of reference.
Plesski is silent on the distance between the busbars and electrode fingers and does not disclose the limitation “a length of the first gap in the first direction and a length of the second gap in the first direction are both about 0.92p or longer.”
However, Tanaka, in the same field of endeavor, discloses this limitation, as set forth below.
PNG
media_image3.png
561
823
media_image3.png
Greyscale
Tanaka discloses in Figs. 2A-B, 4, 71 and the corresponding description:
an acoustic wave device (Fig. 4, annotated, Lamb-wave resonator 1, ¶¶10, 108-119) comprising:
a piezoelectric film made of lithium niobate or lithium tantalate (¶ 231, “quartz substrate 10 is exemplified as a piezoelectric substrate, however, a piezoelectric material other than quartz crystal can be employed. For example, lithium tantalate, lithium niobate…”);
a first busbar electrode (21d) and a second busbar electrode (22c) located on the piezoelectric film (10) and opposite to each other (Fig. 4, ¶¶111-112);
a first electrode finger (21a) and a second electrode finger (22a) on the piezoelectric film (10), the first electrode finger including one end coupled to the first busbar electrode (21d), the second electrode finger (22a) including one end coupled to the second busbar electrode (21c);
the first electrode finger and the second electrode finger extend in a first direction (Figs. 2A-B, 4, Y-axis), the first direction is perpendicular to a second direction (X-axis), the first electrode finger and the second electrode finger face each other in the second direction (X-axis);
a first gap (Wg) is provided between the first busbar electrode and the second electrode finger, and a second gap (Wg) is provided between the second busbar electrode and the first electrode finger (Fig. 4);
and a length of the first gap in the first direction and a length of the second gap in the first direction are both about 0.92p or longer. Tanaka discloses a center-to-center distance between the first electrode finger (21a) and the second electrode finger (22a) is equal to λ/2 (¶115). (It is noted that Tanaka defines “pitch” as the distance between the electrodes coupled to the same busbar. That definition is not used in the rejection.) Tanaka further discloses the length of the gap Wg from 1λ to 23λ (Figs. 5-71), or if expressed in terms of the center-to-center distance between the electrode fingers, from 2p to 46p, a range overlapping the ranges recited in claims 11-13.
It would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to modify the acoustic wave device of Plesski to have the length of the first gap in the first direction and the length of the second gap in the first direction about 0.92p or longer [and about 3p or shorter] for the benefit of improving the Q value and coupling coefficient of the acoustic wave device, as taught by Tanaka (¶¶209-212).
One of ordinary skill would have been motivated to carry out this modification with a reasonable expectation of success because both Plesski and Tanaka disclose structurally and operationally similar acoustic wave devices using similar IDT structures, similar types of acoustic waves, made of similar materials and used in similar applications. See, e.g., Tanaka, ¶¶4-5, 102, 108, 116, 126-127, a Lamb-wave resonator uses a “plate wave, which is a bulk wave propagating inside a substrate by repeating reflections between upper and lower surfaces of the substrate”; see also Prov. App. No. 62/685,825 (Figs., 5-6) (describing XBAR as using A1 Lamb wave mode); Prov. App. No. 62/701,363 (Figs. 1-6, pp. 1-14) (same); Prov. App. No. 62/741,702 (Fig. 2, p. 5) (same); Prov. App. No. 62/748,883 (Fig. 2, p. 5) (same), to all of which Plesski claims priority.
Plesski in view of Tanaka discloses:
Claim 15
wherein when viewed in the second direction, a region in which the first electrode finger and the second electrode finger that are adjacent to each other overlap is an excitation domain, and MR < 1.75(d/p) + 0.075, where MR is a metallization ratio of the first electrode finger and the second electrode finger to the excitation domain.
The metallization ratio of the first and second electrode fingers is equal to the width of the first and second electrode fingers multiplied by the overlap between the fingers. The excitation domain area is equal to the pitch of the first and second electrode fingers multiplied by the overlap between the fingers. That is, MR is equal to 2*width/pitch. The claims therefore require that 2*width/pitch < 1.75(d/p) + 0.075.
Plesski discloses that the pitch of the IDT is typically 2 to 20 times the width of the fingers and 2 to 20 times the thickness of the piezoelectric plate (5:7-10). Plesski therefore discloses the metallization ratio (2*width/pitch) between 0.1 to 1 and d/p between 0.05 to 0.5. Substituting the value of d/p into the formula recited in the claims, the claims require MR <1.75*(0.05 to 5) + 0.075<0.1625 to 0.95. Plesski discloses the metallization ratio MR ranging from 0.1 to 1, overlapping the range 0.1625 to 0.95 required by the claim.
Claim 16
wherein a thickness of the piezoelectric film is about 40 nm to about 1000 nm (Plesski, 9:31-32, the XBARs are formed on a 0.4 micron thickness Z-cut lithium niobate plate,” Fig. 8, piezoelectric plate thickness ts ranges from 200 to 800 nm).
Claim 17
wherein the acoustic wave device does not contain a reflector (Plesski, Fig. 1, acoustic device 100 does not contain a reflector).
Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Plesski in view of Tanaka and in further view of U.S. Patent Application Publication No. 2022/0014172 A1, published Jan. 13, 2022 (“Nozoe”).
Plesski in view of Tanaka discloses all the limitations of claim 20 except a plurality of first dummy electrode fingers and a plurality of second dummy electrode fingers.
However, Nozoe, in the same field of endeavor, discloses this limitation (Figs. 2, 3, dummy electrodes 29A, 29B, ¶¶47, 54, 91).
It would have been obvious to one of ordinary skill in the art to further modify Plesski to add a plurality of dummy electrode fingers for the benefit of improving phase characteristics, as taught by Nozoe (¶92-93). One of ordinary skill would have been motivated to carry out this modification with a reasonable expectation of success because Plesski, Tanaka and Nozoe disclose structurally and operationally similar acoustic wave devices using similar IDT structures, similar types of acoustic waves, made of similar materials and used in similar applications. See rejection of claim 1 above regarding Plesski and Tanaka, see also Nozoe, ¶¶6, 41, 59-61.
Allowable Subject Matter
Claims 1-10 are allowed.
The following is a statement of reasons for the indication of allowable subject matter: the closest prior art references of Plesski, Tanaka, and Nozoe, either individually or in combination, do not disclose or render obvious the features of “the acoustic wave device being configured to use a bulk wave in a first thickness-shear mode" and “a length of the first gap in the first direction and a length of the second gap in the first direction are both about 0.92p or longer, where p is a center-to-center distance between the first electrode finger and the second electrode finger, and the first electrode finger and the second electrode finger are adjacent to each other,” in combination with the remaining limitations of claim 1.
Claim 2-10 are allowable as dependent on the allowable claim 1.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to VICTOR COLE, telephone number (571) 272-4686. The examiner can be reached Monday-Friday, 9AM-5PM ET.
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 www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, ANDREA LINDGREN BALTZELL, can be reached at (571) 272-5918. 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 www.uspto.gov/patents/apply/patent-center for more information about Patent Center and 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.
/VICTOR COLE/
Examiner, Art Unit 2843
/ANDREA LINDGREN BALTZELL/Supervisory Patent Examiner, Art Unit 2843