Samsung Electronics Co., Ltd. et al.

Prosecution History analysis

Examiner Search analysis

Invalidity Framework analysis

Petition

Petition Analysis

## 1. Case Identification
- Case #: [IPR2025-00997](https://ai-lab.exparte.com/case/ptab/IPR2025-00997)
- Patent #: [9,525,084](https://ai-lab.exparte.com/patent/9525084)
- Filed: July 14, 2025
- Petitioner(s): [Samsung Electronics Co., Ltd.](https://ai-lab.exparte.com/party/samsung-electronics-america-inc), [Samsung Electronics America, Inc.](https://ai-lab.exparte.com/party/samsung-electronics-america-inc), [Samsung Semiconductor, Inc.](https://ai-lab.exparte.com/party/samsung-semiconductor-inc), and [Samsung Austin Semiconductor LLC](https://ai-lab.exparte.com/party/samsung-austin-semiconductor-llc)
- Patent Owner(s): [W&WSENS DEVICES INC.](https://ai-lab.exparte.com/party/w-wsens-devices-inc)
- Challenged Claims: 1-9, 11-15, 17-21, and 24

## 2. Patent Overview
- Title: Integrated Detector/Processor Circuit
- Brief Description: The [’084 patent](https://ai-lab.exparte.com/case/ptab/IPR2025-00997/doc/1001) discloses an integrated single-chip device that combines a photodetector with an electronic processor. The key feature is a microstructure-enhanced photodetector that uses a plurality of holes etched into a silicon absorption layer to improve light absorption efficiency, particularly for data communication applications.

## 3. Grounds for Unpatentability

#### Ground 1: Claims 1-9, 11-15, 17-21, and 24 are obvious over Harada in view of Hasegawa.
  - **Prior Art Relied Upon:** [Harada](https://ai-lab.exparte.com/case/ptab/IPR2025-00997/doc/1004) (Japanese Patent Application Publication No. JP2002-314116A) and [Hasegawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00997/doc/1005) (Japanese Patent Application Publication No. JP2007-129024A).
  - **Core Argument for this Ground:**
    - **Prior Art Mapping:** Petitioner argued that Harada discloses the core features of the claimed microstructure-enhanced photodetector. Specifically, Harada teaches a lateral-type PiN photodiode with a plurality of holes etched into its i-layer to improve light-receiving sensitivity and response speed for high-speed signals. Hasegawa teaches the integration of PiN photodiodes with signal-processing circuitry (including CMOS devices and op-amps) on a single semiconductor chip to create a compact, high-speed optical data communication device. The combination of Harada’s photodetector with Hasegawa’s integrated circuit design allegedly renders the limitations of the independent claims obvious. Harada provides the photodetector with holes, while Hasegawa provides the single-chip integration with an electronic processor.
    - **Motivation to Combine (for §103 grounds):** A person of ordinary skill in the art (POSITA) would combine Harada and Hasegawa to gain the known benefits of single-chip integration, as taught by Hasegawa. These benefits include creating a more reliable and smaller device, reducing manufacturing costs, and improving performance by shortening the connection between the photodetector and processing circuitry, which minimizes signal attenuation and noise. A POSITA would have been motivated to incorporate Harada’s enhanced-sensitivity photodiode into Hasegawa’s integrated system to improve the overall performance of the optical data communication device.
    - **Expectation of Success (for §103 grounds):** A POSITA would have had a reasonable expectation of success because both references disclose silicon-based PiN photodiodes and CMOS-compatible fabrication processes. Combining these known elements using known manufacturing techniques would have yielded the predictable result of an integrated, high-sensitivity photodetector chip.

#### Ground 2: Claim 7 is obvious over Harada and Hasegawa in view of NXP.
  - **Prior Art Relied Upon:** Harada (Japanese Patent Application Publication No. JP2002-314116A), Hasegawa (Japanese Patent Application Publication No. JP2007-129024A), and [NXP](https://ai-lab.exparte.com/case/ptab/IPR2025-00997/doc/1006) (European Patent Application EP 2 172 974 A1).
  - **Core Argument for this Ground:**
    - **Prior Art Mapping:** This ground specifically targets claim 7, which adds limitations for "one or more additional photodetectors" that receive "respective additional source signals." Petitioner argued that this language encompasses detecting different wavelength bands, a known technique in wavelength division multiplexing (WDM). While the Harada-Hasegawa combination teaches an array of identical photodetectors receiving spatial portions of a signal, NXP explicitly teaches configuring an array of photodiodes to detect different wavelengths by varying the hole dimensions in each diode.
    - **Motivation to Combine (for §103 grounds):** A POSITA, seeking to expand the functionality of the Harada-Hasegawa device, would have been motivated to incorporate NXP’s teachings. Modifying the array of Harada-type photodiodes in the Hasegawa integrated system to have varied hole dimensions as taught by NXP would enable the device to detect multiple wavelength channels simultaneously. This modification would increase data bandwidth and the speed of optical data transmissions, a known advantage of WDM.
    - **Expectation of Success (for §103 grounds):** Success would be expected as NXP, like Harada and Hasegawa, discloses silicon-based photodiodes and compatible fabrication processes. Applying NXP’s known technique of varying hole sizes to the Harada-Hasegawa device is a predictable design choice for achieving WDM capabilities.

#### Ground 3: Claims 5 and 14 are obvious over Harada and Hasegawa in view of Yahaya.
  - **Prior Art Relied Upon:** Harada (Japanese Patent Application Publication No. JP2002-314116A), Hasegawa (Japanese Patent Application Publication No. JP2007-129024A), and [Yahaya](https://ai-lab.exparte.com/case/ptab/IPR2025-00997/doc/1007) (a 2013 article in *Optics Express*).
  - **Core Argument for this Ground:**
    - **Prior Art Mapping:** This ground addresses claims 5 and 14, which require the photodetector to have an absorption percentage that varies by less than 20% over specified wavelength spans between 800 nm and 900 nm. Petitioner asserted that Yahaya demonstrates that these performance characteristics were known and achievable. Yahaya discloses absorption measurements for silicon photodiodes with periodic nanohole arrays, showing high absorption (78-95%) with less than 20% variation in the 800-900 nm range.
    - **Motivation to Combine (for §103 grounds):** A POSITA building the Harada-Hasegawa device would have been motivated to optimize its performance for reliable and consistent operation across a target wavelength range. Yahaya provides specific, optimized hole dimensions and spacing to achieve the exact type of stable, high-absorption performance recited in claims 5 and 14. A POSITA would therefore have been motivated to modify the hole parameters of Harada’s photodiode based on the teachings of Yahaya to achieve these desirable and known absorption characteristics.
    - **Expectation of Success (for §103 grounds):** A POSITA would have reasonably expected success in achieving the claimed absorption performance. Yahaya provides empirical data demonstrating that silicon photodetectors with nanohole arrays—a structure analogous to Harada’s—can achieve the claimed low-variation absorption. Modifying the dimensions of Harada's holes to align with the optimized parameters from Yahaya would be a straightforward design modification.

## 4. Relief Requested
- Petitioner requests that the Board institute an inter partes review and cancel claims 1-9, 11-15, 17-21, and 24 of Patent 9,525,084 as unpatentable.

Samsung targets photodetector circuit patent: Harada & Hasegawa prior art cited for 20 claims as obvious over single-chip integration of etched holes.