DCT

1:18-cv-00488

Photonic Imaging Solutions Inc v. ASUSTeK Computer Inc

Log In

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:18-cv-00488, D. Del., 04/02/2018
  • Venue Allegations: Plaintiff alleges venue is proper in any judicial district because Defendant is not a resident of the United States.
  • Core Dispute: Plaintiff alleges that Defendant’s consumer electronic products, which incorporate certain CMOS image sensors, infringe four U.S. patents related to the fabrication, design, and integration of such sensors.
  • Technical Context: CMOS (Complementary Metal-Oxide-Semiconductor) image sensors are a foundational technology for digital imaging, widely used in products such as laptop webcams, smartphones, and digital cameras.
  • Key Procedural History: The complaint does not allege any prior litigation, Inter Partes Review (IPR) proceedings, or licensing history related to the patents-in-suit.

Case Timeline

Date Event
1998-02-28 '055 Patent Priority Date
1998-06-29 '187 Patent Priority Date
1998-06-29 '388 Patent Priority Date
2001-02-06 '055 Patent Issue Date
2002-05-07 '203 Patent Priority Date
2003-05-13 '187 Patent Issue Date
2005-09-27 '388 Patent Issue Date
2006-09-26 '203 Patent Issue Date
2018-04-02 Complaint Filing Date

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

U.S. Patent No. 6,184,055 - “CMOS Image Sensor with Equivalent Potential Diode and Method for Fabricating the Same,” issued February 6, 2001

The Invention Explained

  • Problem Addressed: The patent describes a problem in prior art CMOS image sensor fabrication where using a single mask for implanting different ion types could lead to a "pinning region" becoming electrically isolated from the underlying semiconductor layer. This isolation prevents the photodiode from fully depleting, which can degrade sensor performance, especially at the low operating voltages required by modern electronics ('055 Patent, col. 2:56-67).
  • The Patented Solution: The invention proposes a fabrication method using two separate ion implantation masks. A first mask is used to form an initial impurity region (an N- region). A second, larger mask is then used to form a second impurity region (a P-pinning layer) that is intentionally wider than the first. This wider geometry ensures that the pinning layer makes direct contact with the underlying semiconductor substrate, maintaining an equivalent potential and allowing for complete photodiode depletion at low voltages ('055 Patent, Abstract; col. 9:1-7).
  • Technical Importance: This method was designed to produce more reliable low-voltage CMOS image sensors, facilitating their integration into the growing market of compact, power-sensitive consumer electronics ('055 Patent, col. 3:18-24).

Key Claims at a Glance

  • The complaint asserts independent method claim 1 (Compl. ¶14).
  • Essential elements of claim 1 include:
    • Providing a semiconductor layer of a first conductive type.
    • Forming an isolation layer to define active and field regions.
    • Forming a first impurity region (of a second conductive type) using a first ion implantation mask, keeping it apart from the isolation layer.
    • Forming a second impurity region (of the first conductive type) using a second ion implantation mask, such that its width is wider than the first impurity region and a portion of it contacts the underlying semiconductor layer.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 6,563,187 - “CMOS Image Sensor Integrated Together with Memory Device,” issued May 13, 2003

The Invention Explained

  • Problem Addressed: The patent notes that conventional imaging systems required separate chips for the image sensor and for memory (e.g., DRAM), which increased manufacturing costs, system size, and power consumption ('187 Patent, col. 1:44-53).
  • The Patented Solution: The invention describes a single-chip solution where three distinct functional blocks—a pixel array for capturing light, a logic circuit for processing signals, and a memory for storing data—are fabricated on the same semiconductor substrate. Critically, these sections are isolated from one another by insulating layers to prevent interference, enabling a fully integrated system-on-a-chip ('187 Patent, Abstract; col. 2:1-9; Fig. 2A).
  • Technical Importance: This integration of sensing, logic, and memory onto a single chip was a significant step toward creating the smaller, cheaper, and more power-efficient imaging modules necessary for mobile and consumer electronics ('187 Patent, col. 1:54-61).

Key Claims at a Glance

  • The complaint asserts independent product claim 4 (Compl. ¶26).
  • Essential elements of claim 4 include:
    • A chip divided into first, second, and third sections, all formed in a single P-type layer.
    • A unit pixel array in the first section.
    • A logic circuit in the second section to process signals from the pixel array.
    • A memory in the third section to store outputs from the logic circuit.
    • The first, second, and third sections are isolated from each other by insulating layers.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 6,949,388 - “CMOS Image Sensor Integrated Together with Memory Device,” issued September 27, 2005

  • Technology Synopsis: As a divisional of the application that led to the ’187 Patent, this patent claims a method of manufacturing an integrated CMOS image sensor. It focuses on the process of forming a unit pixel, a logic cell, and a memory cell on a single substrate, with isolation regions formed between the different functional cells to enable single-chip integration ('388 Patent, Abstract; col. 1:54-67).
  • Asserted Claims: The complaint asserts at least method claim 31 (Compl. ¶39).
  • Accused Features: The complaint alleges that the method of fabricating the Omnivision OV298BB sensor involves forming a unit pixel, a logic cell, and a memory cell, with first and second isolation regions separating them, thereby infringing the claimed method (Compl. ¶41-45).

U.S. Patent No. 7,113,203 - “Method and System for Single-Chip Camera,” issued September 26, 2006

  • Technology Synopsis: This patent describes a complete single-chip camera system that integrates an image sensor, image processor, data storage, and a communication interface. A notable aspect of the invention is a "test access element," comprising I/O pins controlled by an on-chip multiplexer, which allows internal data pathways to be accessed externally for verifying the functionality of individual components during manufacturing and testing ('203 Patent, Abstract; col. 2:46-51, col. 6:3-12).
  • Asserted Claims: The complaint asserts at least product claims 1 and 27 (Compl. ¶52).
  • Accused Features: The accused Omnivision OV298BB sensor is alleged to be a single-chip camera containing an image sensor, image-processing element, data storage, communication interface, an on-chip multiplexer, a register set, and a test access element with I/O pins, which together allegedly meet the claim limitations (Compl. ¶54-63).

III. The Accused Instrumentality

Product Identification

  • The complaint accuses a range of Defendant's products, including "laptop computers, tablets, desktop computers, all in one computers, and smartphones" (Compl. ¶14). The "EE PC1215N Netbook" is identified as an exemplary accused product (Compl. ¶14). The specific infringing component is identified as the "Omnivision OV298BB CMOS image sensor" and other similar sensors contained within Defendant's products (Compl. ¶15).

Functionality and Market Context

  • The accused instrumentality is a CMOS image sensor component used to capture images for applications such as webcams in laptops (Compl. ¶14, ¶20). The complaint includes a photograph of the accused sensor, showing die markings that identify it as an "Omnivision OV298BB" model (Compl. ¶15). The allegations assert that this sensor is fabricated using specific layering and implantation techniques (Compl. ¶16-19), and that it integrates sensing, logic, memory, and testing capabilities on a single chip (Compl. ¶28-32, ¶54-63). The complaint positions these sensors as components within high-volume consumer electronics, suggesting significant commercial activity (Compl. ¶14).

IV. Analysis of Infringement Allegations

’055 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
providing a semiconductor layer of a first conductive type; The accused Omnivision OV298BB sensor is fabricated using a method that provides a "P-epi layer." ¶16 col. 10:41-43
forming an isolation layer dividing the semiconductor layer into a field region and an active region; The method includes forming an isolation layer that divides the semiconductor layer into a field region (between unit cells) and an active region (the photodiode within a unit cell). ¶17 col. 10:45-46
forming a first impurity region of a second conductive type within the semiconductor layer using a first ion implantation mask, wherein the first ion implantation mask covers a portion of the semiconductor layer so that the first impurity region is apart from the isolation layer; and The method includes forming an N-Diffusion layer using a first ion implantation mask, where the layer is structurally separate from the isolation layer. ¶18 col. 10:47-54
forming a second impurity region of the first conductive type beneath a surface of the semiconductor layer and on the first impurity region using a second ion implantation mask... so that a width of the second impurity region is wider than that of the first impurity region... The method includes forming a P-pinning layer using a second ion implantation mask, where the mask opening results in the P-pinning layer being wider than the N-Diffusion layer. ¶19 col. 10:55-68

Identified Points of Contention

  • Liability for Method Claims: Claim 1 is a method claim for fabricating a sensor. The complaint alleges infringement under 35 U.S.C. § 271(g) by importing products (the Netbook) containing a component (the OV298BB sensor) made by a patented process abroad (Compl. ¶14). A central question will be whether Plaintiff can prove that Omnivision, the sensor supplier, actually uses the claimed two-mask fabrication method.
  • Technical Questions: Evidentiary analysis of the accused sensor will be required to determine if the "P-pinning layer" is demonstrably "wider" than the "N-Diffusion layer" as required by the claim.

’187 Patent Infringement Allegations

Claim Element (from Independent Claim 4) Alleged Infringing Functionality Complaint Citation Patent Citation
a chip divided into first, second and third sections, the sections being formed in a single P-type layer; The accused Omnivision OV298BB sensor is a chip with first, second, and third sections formed in a single P-type layer. ¶28 col. 14:40-42
a unit pixel array formed in the first section operable to detect light from an object; The chip's first section contains a "unit pixel array" that detects light. ¶29 col. 14:43-44
a logic circuit formed in the second section operable to process signals from the pixel array; The chip's second section contains a "logic circuit," such as data processing and sample and hold logic, to process signals. ¶30 col. 14:45-46
a memory formed in the third section operable to store outputs from the logic circuit... The chip's third section contains "memory such as SRAM" that stores outputs from the logic circuit. ¶31 col. 14:47-49
wherein the first, second and third sections are isolated from each other by insulating layers. The three sections on the chip are isolated from one another by insulating layers. ¶32 col. 14:50-52

Identified Points of Contention

  • Scope Questions: A primary issue for the court may be construing the scope of terms like "logic circuit" and "memory". The case may raise the question of whether small, transient buffers or registers within the accused sensor qualify as the "memory" recited in the claim, or if the claim requires a more substantial, dedicated memory block like an SRAM array.
  • Technical Questions: The infringement analysis will depend on physical evidence from the accused OV298BB sensor. A key question is whether the chip architecture, upon inspection, actually contains three distinct and physically isolated sections corresponding to a pixel array, logic, and memory.

V. Key Claim Terms for Construction

Term from '055 Patent, Claim 1: "a width of the second impurity region is wider than that of the first impurity region"

  • Context and Importance: This geometric relationship is the central feature of the patented method, intended to solve the technical problem of electrical isolation of the pinning layer. Proving that the accused sensor possesses this exact structure is fundamental to the plaintiff's infringement case for the '055 patent.
  • Intrinsic Evidence for a Broader Interpretation: The specification explains the purpose is to ensure "a portion of the second impurity region is in contact with the semiconductor layer" ('055 Patent, col. 4:11-14). A party could argue that any configuration where the second region is sufficiently wider to achieve this contact meets the limitation, regardless of the specific dimensions or fabrication details.
  • Intrinsic Evidence for a Narrower Interpretation: The patent's detailed description and figures (e.g., Figs. 7F, 7G, 8A, 8B) show a specific two-mask process that results in this wider region. A party could argue the claim should be limited to structures resulting from this disclosed process, not just any structure that happens to have a wider second region.

Term from '187 Patent, Claim 4: "memory"

  • Context and Importance: The definition of this term is critical to the scope of Claim 4. The infringement question may turn on whether the on-chip storage in the accused sensor qualifies as "memory." Practitioners may focus on this term because its construction will determine whether the claim covers chips with minimal on-board buffers or requires chips with more substantial, dedicated memory blocks.
  • Intrinsic Evidence for a Broader Interpretation: The claim uses the general term "memory". The specification provides "DRAMS or SRAMS" as non-limiting examples, suggesting the term is not restricted to these specific types ('187 Patent, col. 2:34-35).
  • Intrinsic Evidence for a Narrower Interpretation: The patent's background focuses on the problem of integrating image sensors with separate, large memory chips ('187 Patent, col. 1:44-53). A party could argue that, in this context, "memory" should be construed to mean a distinct, functional memory block for storing image data, not merely incidental registers or small buffers inherent to logic circuit operation.

VI. Other Allegations

Indirect Infringement

  • The complaint alleges induced infringement for all four patents. The allegations state that Defendant knowingly induces its customers to infringe by supplying products like the EE PC1215N Netbook "for use in an infringing manner" (Compl. ¶21, ¶34, ¶47, ¶65). The pleadings do not cite specific instructional materials or other affirmative acts of inducement beyond the sale of the products themselves.

Willful Infringement

  • Willfulness is alleged for all patents based on Defendant’s knowledge of infringement "at least as of the date of this Complaint" (Compl. ¶21, ¶34, ¶47, ¶65). This frames the allegation as one of post-suit willfulness. The complaint also alleges willful blindness (Compl. ¶22, ¶35, ¶48, ¶66).

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

  • A central issue will be one of evidentiary proof: can the plaintiff, through reverse engineering or discovery from the non-party supplier (Omnivision), demonstrate that the accused sensor physically embodies the specific fabrication geometries and single-chip architectures required by the patent claims?
  • The case will also turn on a question of claim scope and construction, particularly for the '187 patent: can the term "memory," which was used to solve the problem of integrating large, separate memory chips, be construed broadly enough to read on the type and quantity of on-chip storage present in the accused sensor?
  • Finally, a key legal question for the method claims ('055 and '388 patents) will be one of liability under 35 U.S.C. § 271(g): can the plaintiff establish that Asus is liable for importing products containing sensors that were manufactured abroad using the patented methods, a theory that shifts the factual inquiry from the defendant's actions to those of its third-party component supplier?