Qorvo Inc v. Akoustis Tech Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Qorvo, Inc. (Delaware)
  • Defendant: Akoustis Technologies, Inc. and Akoustis, Inc. (Delaware)
  • Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP; Sheppard, Mullin, Richter & Hampton LLP
• Case Identification: 1:21-cv-01417, D. Del., 02/18/2022
• Venue Allegations: Venue is alleged to be proper in the District of Delaware because Defendant Akoustis is a Delaware corporation and therefore resides in the district.
• Core Dispute: Plaintiff alleges that Defendant’s bulk acoustic wave (BAW) radio frequency (RF) filter products infringe patents related to resonator structure and performance optimization.
• Technical Context: The technology involves BAW filters, which are critical components for selecting specific frequency bands and preventing interference in modern wireless communication devices like smartphones.
• Key Procedural History: The complaint alleges that Defendant was founded by a former vice-president of Plaintiff's predecessor company (RFMD) and that a majority of its board consists of ex-Qorvo/RFMD employees. Plaintiff frames the dispute within a broader context of alleged employee "poaching" and misappropriation of proprietary information, which it claims provided Defendant with knowledge of the patents-in-suit. The complaint also includes counts for false advertising, false patent marking, and unfair competition.

Case Timeline

Date	Event
2002-12-13	U.S. Patent No. 7,522,018 Priority Date
2009-04-21	U.S. Patent No. 7,522,018 Issued
2014-01-01	Defendant Akoustis Founded
2015-08-20	U.S. Patent No. 9,735,755 Priority Date
2017-08-15	U.S. Patent No. 9,735,755 Issued
2022-02-18	First Amended Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 7,522,018 - "Electro-Acoustic Resonator With A Top Electrode Layer Thinner Than A Bottom Electrode Layer," Issued April 21, 2009

The Invention Explained

• Problem Addressed: The patent describes the challenge of achieving high "coupling factors" in thin-film BAW resonators, which is necessary for creating filters with sufficient bandwidth for applications like 3G wireless handsets. It notes that the thin-film piezoelectric materials used in these resonators inherently have a "rather low coupling coefficient" that limits performance (’018 Patent, col. 1:11-25).
• The Patented Solution: The invention proposes a specific structural design for the resonator to overcome this limitation. It claims an electro-acoustic resonator, such as a Film Bulk Acoustic Resonator (FBAR), where the two electrode layers sandwiching the piezoelectric material have unequal thicknesses. Specifically, the top electrode layer is constructed to be thinner than the bottom electrode layer. This asymmetrical arrangement is asserted to achieve an "optimum coupling factor" and thereby increase the filter's bandwidth (’018 Patent, Abstract; col. 2:60-67).
• Technical Importance: This approach provided a structural method for maximizing the achievable bandwidth of BAW filters, a critical parameter for meeting the performance standards of emerging wireless protocols at the time (’018 Patent, col. 1:26-29).

Key Claims at a Glance

• The complaint asserts independent claim 1 (Compl. ¶78).
• The essential elements of independent claim 1 are:
  • An electro-acoustic resonator comprising a membrane structure FBAR.
  • The FBAR has a layer structure with a piezoelectric layer and top and bottom electrode layers.
  • The thicknesses of the two electrode layers are unequal.
  • The top electrode layer is thinner than the bottom electrode layer.
  • This structure is "to increase a filter bandwidth of the electro-acoustic resonator."
• The complaint does not explicitly reserve the right to assert dependent claims but references infringement of "one or more claims" (Compl. ¶78).

U.S. Patent No. 9,735,755 - "BAW Resonator Having Lateral Energy Confinement And Methods of Fabrication Thereof," Issued August 15, 2017

The Invention Explained

• Problem Addressed: The patent addresses the problem of "lateral leakage of mechanical energy" in BAW resonators. This occurs when acoustic energy escapes from the "active region" of the resonator into the surrounding "outer region," which degrades the device's quality factor (Q), a key measure of its efficiency and performance (’755 Patent, col. 2:14-24).
• The Patented Solution: The invention describes a method for engineering the outer region of the BAW resonator to confine energy within the active region. This is achieved by adding "one or more material layers" on the surface in the outer region. The thickness of these added layers is a multiple (n, where n≠1) of the thickness of the passivation layer over the active region. This specific thickness relationship is designed to create an "acoustic match" between the active and outer regions, which prevents the excitation of wavelengths that cause energy leakage, thereby reducing the lateral dispersion and improving the Q factor (’755 Patent, Abstract; col. 2:51-62).
• Technical Importance: This invention provides a technique to mitigate a primary source of energy loss in BAW resonators, enabling the design of higher-performance filters with lower insertion loss and better selectivity, which are valuable for advanced wireless systems (’755 Patent, col. 1:20-34).

Key Claims at a Glance

• The complaint asserts independent claim 9 (Compl. ¶90).
• The essential elements of independent claim 9 are:
  • A BAW resonator with a piezoelectric layer, a first (bottom) electrode, and a second (top) electrode.
  • A passivation layer on the surface of the second electrode within an "active region," having a thickness (TPA).
  • One or more material layers on the surface adjacent to the second electrode in an "outer region."
  • The material layers in the outer region have a thickness that is "n times the thickness (TPA)," where n is a value other than 1.
  • The value "n" is such that the outer and active regions are "acoustically matched" to prevent wavelengths that cause energy leakage from being excited in the active region.
• The complaint does not explicitly reserve the right to assert dependent claims but references infringement of "one or more claims" (Compl. ¶90).

III. The Accused Instrumentality

• Product Identification: The complaint identifies Defendant's "3-7 GHz BAW RF filter portfolio" as the Accused Products (Compl. ¶44, ¶77). Specific examples cited include the AKF-1252, AKF-1256, AKF-1336, and AKF-10235 filters (Compl. ¶77, ¶89).
• Functionality and Market Context: The Accused Products are described as BAW resonator filters, a "vital component in advanced radio frequency filtering solutions for wireless devices" (Compl. ¶15). Their function is to filter out unwanted signals and prevent interference between devices using adjacent frequency bands (Compl. ¶15-16). The complaint alleges these products were built using Plaintiff's patented technology and compete directly with Plaintiff's own BAW filters (Compl. ¶42, ¶44).

IV. Analysis of Infringement Allegations

'018 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
Electro-acoustic resonator... comprising a membrane structure FBAR... with a layer structure comprising a piezoelectric layer and a top and a bottom electrode layer	The Accused Products are identified as film bulk acoustic resonators ("FBAR") that have a membrane structure with a piezoelectric layer and top and bottom electrode layers.	¶78	col. 2:10-15
with the thickness... of the two electrode layers being unequal, characterised in that the top electrode layer is thinner than the bottom... electrode layer	The Accused Products are alleged to be configured with unequal electrode thicknesses. As an example, the Akoustis AKF-10235 BAW Filter is alleged to have a top electrode layer averaging 110 nm thick and a bottom electrode layer averaging 129 nm thick.	¶79	col. 2:63-67
to increase a filter bandwidth of the electro-acoustic resonator.	The Accused Products are alleged to have increased filter bandwidth performance. The complaint references a graph from the AKF-10235 datasheet as evidence of this performance.	¶80	col. 2:67-col. 3:1

The complaint provides a graph from the AKF-10235 datasheet, showing the S21 passband performance, as evidence for the "increased filter bandwidth performance" element (Compl. p. 23).

• Identified Points of Contention:
  • Scope Questions: A central question may be the interpretation of the functional limitation "to increase a filter bandwidth." The dispute may focus on whether this requires a comparison against a baseline (e.g., a symmetric-electrode version of the same device) to prove an "increase," or if the claim is met simply by having a structure that is known to result in wider bandwidth.
  • Technical Questions: What evidence will be required to demonstrate that the accused structure, and not other design factors, is the reason for the alleged bandwidth performance? The complaint's reliance on a product datasheet graph (Compl. p. 23) suggests this will be a factual dispute requiring technical evidence.

'755 Patent Infringement Allegations

Claim Element (from Independent Claim 9)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A BAW resonator comprising: a piezoelectric layer; a first electrode on a first surface...; a second electrode on a second surface...	The Accused Products are alleged to be BAW resonators containing a piezoelectric layer, a first electrode, and a second electrode.	¶90	col. 2:35-39
a passivation layer on a surface of the second electrode... within an active region of the BAW resonator, the passivation layer having a thickness (TPA)...	The Accused Products are alleged to include a passivation layer on the surface of the second electrode within the active region of the resonators.	¶91	col. 2:39-42
one or more material layers on the second surface of the piezoelectric layer adjacent to the second electrode in an outer region... having a thickness that is n times the thickness (TPA)... wherein: n is a value other than 1	The Accused Products are alleged to include one or more material layers in an outer region. The complaint alleges that for the AKF-10235 filter, these layers have a thickness of "about 1.5 to 1.6 times a thickness of the passivation layer within the active region," which satisfies n≠1.	¶92	col. 2:42-49
and n is such that the outer region... and the active region... are acoustically matched in such a manner that one or more wavelengths that cause energy leakage into the outer region are not excited in the active region.	The complaint alleges that in the Accused Products, "n" is such that the regions are acoustically matched, preventing the excitation of energy leaked into the outer region.	¶93	col. 2:57-62

• Identified Points of Contention:
  • Scope Questions: Does the structure in the outer region of the accused devices constitute "one or more material layers" as contemplated by the patent, or is it part of a different structure?
  • Technical Questions: A key evidentiary question will be whether the alleged structure in the accused devices (e.g., the n=1.5-1.6 ratio) actually creates the "acoustic match" required by the claim. This is a functional limitation that will likely require complex technical evidence, such as simulation or physical characterization, to prove or disprove that specific energy-leaking wavelengths are not excited.

V. Key Claim Terms for Construction

For the '018 Patent

• The Term: "to increase a filter bandwidth"
• Context and Importance: This term appears as the final, functional limitation of claim 1. Its construction is critical because it may define the required proof of infringement. Practitioners may focus on this term because it raises the question of whether an infringing device must be proven to have an objectively "increased" bandwidth relative to a hypothetical alternative, or if the claim merely recites the intended purpose of the preceding structural limitations.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation (e.g., purpose clause): The phrasing "to increase" may be interpreted as stating the intended result or purpose of the structural design (thinner top electrode), rather than imposing a separate, measurable performance requirement. The patent's objective is to "provide an electro-acoustic resonator which will give increased filter bandwidth" (’018 Patent, col. 2:61-62).
  • Evidence for a Narrower Interpretation (e.g., functional requirement): The claim language is "characterised in that... [the structure] is thinner... to increase a filter bandwidth," which could be read to require that the structure actually achieves the functional result. The patent repeatedly links the asymmetrical structure to achieving "maximum filter bandwidth" and an "optimum coupling-factor" (’018 Patent, col. 3:39-41), suggesting the function is an essential part of the invention.

For the '755 Patent

• The Term: "acoustically matched"
• Context and Importance: This term is the functional heart of claim 9. The patent itself provides a definition: "in such a manner that one or more wavelengths that cause energy leakage into the outer region are not excited in the active region." The entire infringement case for this patent hinges on whether the defendant's products meet this functional definition.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification explains the goal is to avoid "acoustic mismatch between an active region and an outer region" (’755 Patent, col. 6:4-5). A party might argue any structure that measurably reduces lateral energy leakage compared to a conventional device meets the spirit of being "acoustically matched."
  • Evidence for a Narrower Interpretation: The claim provides a very specific functional test: that certain "wavelengths... are not excited." This suggests a narrow, technical requirement. A party could argue that infringement requires proof that the specific physical mechanism described—preventing the excitation of certain wave modes—is present, not just that the general outcome of reduced energy leakage is achieved.

VI. Other Allegations

• Indirect Infringement: The complaint alleges inducement of infringement for both patents. The allegations are based on Defendant publishing instructions on its website, including recommendations and diagrams for soldering, packaging, and PCB layouts, that allegedly instruct customers on how to implement the Accused Products in infringing systems (Compl. ¶82, ¶95).
• Willful Infringement: The complaint alleges willful infringement for both patents. The basis for willfulness is alleged pre-suit knowledge. Plaintiff alleges that numerous former Qorvo employees and executives, who were aware of the patents-in-suit from their time at Qorvo, now hold key positions at Akoustis and brought that knowledge with them (Compl. ¶50-51, ¶83, ¶96).

VII. Analyst’s Conclusion: Key Questions for the Case

This case appears to combine specific technical infringement allegations with a broader narrative of corporate rivalry and alleged misappropriation of intellectual property. The resolution will likely depend on the following central questions:

1. A core issue for the '018 Patent will be one of functional proof: can Plaintiff demonstrate that the accused filters, by virtue of having a thinner top electrode, actually "increase a filter bandwidth"? This may require establishing a baseline for comparison and isolating the effect of the electrode asymmetry from other design choices.
2. A key evidentiary question for the '755 Patent will be one of operational equivalence: does the specific structure in the outer region of the accused filters perform the precise function of creating an "acoustic match" that prevents the excitation of energy-leaking wavelengths, as required by the claim? This highly technical question will likely be a battle of expert analysis and simulation.
3. A central question for willfulness and damages will be one of imputed knowledge: can Plaintiff successfully argue that the knowledge of the patents-in-suit, allegedly held by Defendant's ex-Qorvo employees, constitutes corporate knowledge for Akoustis from the time those employees were hired? The extensive allegations of systematic employee poaching will be critical to this aspect of the case.