Technoprobe Spa v. FormFactor Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Technoprobe S.p.A. (Italy)
  • Defendant: FormFactor, Inc. (Delaware)
  • Plaintiff’s Counsel: Shaw Keller LLP; Finnegan, Henderson, Farabow, Garrett & Dunner, LLP
• Case Identification: 1:24-cv-00650, D. Del., 05/31/2024
• Venue Allegations: Venue is alleged to be proper in the District of Delaware because the defendant, FormFactor, Inc., is a Delaware corporation and therefore resides in the district.
• Core Dispute: Plaintiff alleges that Defendant’s probe cards, which incorporate "Metallized Guide Plate" technology, infringe a patent related to testing heads used for verifying semiconductor devices.
• Technical Context: The technology involves high-density probe cards, an electromechanical interface used for testing the functionality of semiconductor chips while they are still on the wafer, a critical quality control step in the semiconductor manufacturing process.
• Key Procedural History: The complaint alleges a contentious history between the parties, including a 2018 litigation that settled and a separate, ongoing 2023 litigation concerning the asserted patent’s grandparent patent. The complaint also alleges that FormFactor was aware of the technology through a 2023 industry conference where Technoprobe presented its "Patented solution" and that FormFactor cited the patent's priority application during the prosecution of its own, unrelated patent.

Case Timeline

Date	Event
2016-12-16	'133 Patent earliest priority date
2018-07-17	Prior litigation between parties commenced
2023-06-05	SWTest 2023 conference begins, where technology was allegedly shown
2023-08-04	Litigation on grandparent patent ('885) commenced
2023-10-19	'133 Patent application published
2024-03-05	U.S. Patent No. 11,921,133 issues
2024-05-31	Complaint filed

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

U.S. Patent No. 11,921,133 - "Testing Head Having Improved Frequency Properties," issued March 5, 2024

The Invention Explained

• Problem Addressed: The patent’s background section identifies a problem in semiconductor testing heads where the high density of contact elements (probes) carrying power and ground signals creates electrical interference and "noise," which can limit the frequency performance of the test and thus its accuracy and speed (’133 Patent, col. 2:42-51). The potential for "disadvantageous ground loops" is also noted as a problem (’133 Patent, col. 2:50-51).
• The Patented Solution: The invention proposes a testing head with a guide plate that has one or more "conductive portions" formed on its surface (’133 Patent, col. 7:30-34). These conductive portions electrically connect all the guide holes for a specific group of probes (e.g., all ground probes or all power probes), thereby creating a common "ground plane" or "power plane" (’133 Patent, col. 7:42-49). By short-circuiting these probes together directly on the guide plate and close to the device under test, the invention aims to reduce signal path length and suppress noise, improving the overall frequency performance of the testing head (’133 Patent, col. 9:30-40). Figure 2A illustrates this by showing a conductive portion (30') that connects the guide holes for a group of first contact elements (21') (’133 Patent, Fig. 2A).
• Technical Importance: This design provides a structural solution to the signal integrity challenges inherent in testing increasingly complex and high-speed semiconductor chips, where distinguishing valid signals from electrical noise is critical (’133 Patent, col. 3:6-14).

Key Claims at a Glance

• The complaint asserts independent claim 1 (Compl. ¶41).
• The essential elements of independent claim 1 are:
  • A testing head configured to verify the operation of a device under test on a semiconductor wafer.
  • A plurality of "buckling beam type" contact elements.
  • At least one guide with guide holes to receive the contact elements.
  • The guide includes a "first conductive portion" that electrically connects a "first group of guide holes" to contact "first contact elements" carrying a "first type of signal."
  • The guide also includes a "second conductive portion" that electrically connects a "second group of guide holes" to contact "second contact elements" carrying a "second type of signal" different from the first.
  • The first and second conductive portions are formed "on a first face" of the guide and are "physically and electrically separated from each other by at least one non-conductive zone."
• The complaint reserves the right to allege infringement under the doctrine of equivalents (Compl. ¶71).

III. The Accused Instrumentality

Product Identification

• The accused products are FormFactor’s “Apollo” and “Kepler” probe cards, as well as other products that allegedly incorporate the same infringing technology (Compl. ¶21, ¶41).

Functionality and Market Context

• The complaint alleges that the accused products incorporate a "Metallized Guide Plate" (MeGP) technology (Compl. ¶27). This feature is promoted by FormFactor as improving the "current carrying capability" (CCC) of the probe card by providing an "alternative current path when overcurrent events occur" and enabling "Improved Contact with the DUT" (Compl. ¶25; Compl. Ex. E, p.13, 19). The complaint presents an analogy slide from a FormFactor presentation, which contrasts a standard design experiencing an "OVERFLOW!!" with the "Distributed" current flow of its MeGP design (Compl. ¶22, Ex. E, p. 12). The complaint alleges that FormFactor and Technoprobe are the two leading competitors in the probe card market (Compl. ¶18).

IV. Analysis of Infringement Allegations

'133 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
A testing head configured to verify the operation of a device under test integrated on a semiconductor wafer...	The Accused Products are probe cards with a "Spring Head," "Guide Plate[s]," and "Probes" configured to test a device on a semiconductor wafer. The complaint references a "Probe Card Cross-Section" diagram from FormFactor materials to support this.	¶43-44	col. 6:30-34
a plurality of contact elements, each including a body that extends between a first end portion and a second end portion, the plurality of contact elements being a buckling beam type	The Accused Products include "Probes," which are alleged to be contact elements of a "buckling beam type."	¶45-46	col. 18:35-37
at least one guide including a plurality of guide holes configured to receive the contact elements	The Accused Products include "Guide Plate[s]" with guide holes for the probes.	¶47-48	col. 6:15-18
a first conductive portion that includes and electrically connects a first group of guide holes... the first contact elements being configured to carry a first type of signal	The guide plates allegedly include "Metallized Guide Plates (MeGP)" that use "metal patterns on the Guide Plate" to connect nets like VDD (power) or GND (ground), which constitutes a first signal type. A diagram showing a "Metal" layer on a "Lower Guide Plate (LGP)" is provided as evidence.	¶49-51, ¶56	col. 8:36-54
a second conductive portion that includes and electrically connects the holes of a second group of the guide holes... the second contact elements being configured to carry a second type of signal that is different from the first type of signal	The "MeGP" technology is alleged to connect a second group of nets (e.g., if the first was ground, the second is power) using different metal patterns on the same guide plate.	¶52-54, ¶56	col. 8:36-54
wherein the first conductive portion and the second conductive portion are formed on a first face of the at least one guide and are physically and electrically separated from each other by at least one non-conductive zone.	FormFactor’s promotional materials allegedly illustrate different conductive portions (e.g., color-coded yellow and green) on the same face of a guide plate, separated by non-conductive zones (e.g., depicted as white). The complaint includes a diagram showing these distinct, color-coded groupings.	¶55-57	col. 9:6-14

• Identified Points of Contention:
  • Scope Questions: A central question may be whether FormFactor’s "Metallized Guide Plate" (MeGP), which the complaint alleges is for improving "Current Carrying Capability" (CCC), meets the functional and structural requirements of the claimed "conductive portion," which the patent describes as creating a common plane to reduce noise and improve frequency performance. The parties may dispute whether improving CCC is technically distinct from the noise-reduction purpose described in the patent.
  • Technical Questions: The infringement allegation relies heavily on interpreting FormFactor’s marketing and presentation diagrams (Compl. ¶57, Ex. E, p. 21). A key question for the court will be whether the physical structure of the accused probe cards actually embodies the claimed features—specifically, whether the "first" and "second" conductive portions are truly separate and formed on a single face, and whether the space between them qualifies as a "non-conductive zone" as required by the claim.

V. Key Claim Terms for Construction

• The Term: "conductive portion"

  • Context and Importance: This term is the technological core of the asserted claim. The case may turn on whether FormFactor’s "Metal" layer or "MeGP" constitutes a "conductive portion." Practitioners may focus on this term because the patent describes its function as creating a common plane for noise reduction, while the complaint alleges the accused feature is for improving current carrying capability.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification describes the feature broadly as "a conductive portion that includes and electrically connects the holes of a group of guide holes" (’133 Patent, col. 4:35-39) and as forming a "common conductive plane" (’133 Patent, col. 7:42-43). This language could support an interpretation covering any conductive layer that connects multiple guide holes.
    • Evidence for a Narrower Interpretation: The specification repeatedly links the conductive portion to improving "frequency performance" and eliminating "noise" (’133 Patent, col. 3:6-14; col. 7:30-34). A defendant might argue that to be a "conductive portion," the feature must be structured for this specific purpose, potentially excluding a feature designed primarily for overcurrent protection.

• The Term: "physically and electrically separated from each other by at least one non-conductive zone"

  • Context and Importance: This limitation defines the relationship between the different signal planes on the guide. The infringement allegation relies on diagrams where different colored areas are separated by white space. The definition of this "zone" is critical to determining if the accused products meet this limitation.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The plain language suggests that any physical gap that prevents electrical current from flowing between the two conductive portions would suffice. The patent states the second conductive portion is "physically separated from the first conductive portion 30' and therefore not electrically connected thereto" (’133 Patent, col. 8:47-49).
    • Evidence for a Narrower Interpretation: The patent also discloses adding a "coating dielectric portion" to cover the non-conductive zones to prevent metallic debris from causing shorts (’133 Patent, col. 9:55-61). A party could argue that a mere absence of conductive material is insufficient and that a "zone" requires a specific, insulating material to ensure reliable separation in the demanding environment of a probe card.

VI. Other Allegations

• Indirect Infringement: The complaint alleges inducement of infringement, stating that FormFactor encourages its customers to use the accused probe cards through promotional materials, its website, and presentations at industry conferences like SWTest 2023 (Compl. ¶59-61). These materials allegedly instruct on the use of the infringing "MeGP" technology and tout its benefits (Compl. ¶61).
• Willful Infringement: The complaint alleges that FormFactor's infringement has been willful. The basis for this allegation is multifaceted, including:
  • Pre-suit Knowledge: FormFactor allegedly had knowledge of the patented technology via (1) its attendance at the SWTest 2023 conference where Technoprobe presented its "Patented solution" (Compl. ¶68); (2) ongoing litigation on the '133 patent's grandparent patent, which allegedly put FormFactor on notice of the technology and patent family (Compl. ¶64-66); and (3) FormFactor’s citation to the '133 patent's priority application during the prosecution of its own patent in 2021 (Compl. ¶67).
  • Post-suit Knowledge: The complaint alleges continued infringement after the patent issued on March 5, 2024, constituting knowledge of the patent itself (Compl. ¶72).

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

• A core issue will be one of technical and definitional mapping: can the "Metallized Guide Plate" technology, which FormFactor markets as a solution for "Current Carrying Capability," be proven to be the same as the "conductive portion" claimed in the '133 patent, which is described as a structure for creating common signal planes to reduce noise and improve frequency performance? The case may depend on whether these are two descriptions of the same solution or two technically distinct concepts.
• A second central question will be one of claim construction: how will the court define a "conductive portion" and the required "non-conductive zone" separating them? The dispute will likely focus on whether the simple patterned metal layers shown in FormFactor's marketing materials are sufficient to meet the claim limitations, or if the patent's specification requires a more specific structure or material composition.
• Finally, should infringement be found, a key battleground will be willfulness. Given the extensive history of litigation and alleged interactions detailed in the complaint, the court will have to determine if FormFactor's actions constituted objective recklessness with regard to a known risk of infringing Technoprobe's patent rights.