US 8974270

US patent 8974270, titled "CMP pad dresser having leveled tips and associated methods," was issued on March 10, 2015. The original assignee was listed as an individual, but the current assignee is Chien-Min Sung, who is also the inventor. The application was filed on May 23, 2012.

Abstract:
The patent describes Chemical Mechanical Polishing (CMP) pad dressers with leveled superabrasive particle tips and methods for making them. A key feature is a matrix layer with a monolayer of superabrasive particles, where each particle protrudes from the matrix. The difference in protrusion distance between the highest and next highest protruding tip is less than or equal to about 20 microns, and the highest 1% of protruding tips are within about 80 microns or less of each other.

Plain-language overview of independent claims:

• Independent Claim 1: This claim describes a CMP pad dresser comprising a matrix layer and a monolayer of multiple superabrasive particles embedded in it. Each particle protrudes from the matrix layer. The significant aspect is the precise leveling of these protruding tips: the height difference between the highest tip and the second highest tip is 20 microns or less, and the height difference among the top 1% of all protruding tips is 80 microns or less. A rigid support is attached to the matrix layer.

• Independent Claim 12: This claim also describes a CMP pad dresser. It features a first monolayer of superabrasive particles on one side of a metal support layer, and a second monolayer of superabrasive particles on the opposite side of the metal support layer. The particles in the second monolayer are arranged in substantially the same distribution as those in the first monolayer. A rigid support is connected to the second monolayer, on the side opposite the first monolayer.

• Independent Claim 15: This claim outlines a method for manufacturing a CMP pad dresser. It involves placing a first monolayer of superabrasive particles on one side of a metal support layer, and a second monolayer on the opposite side. The superabrasive particles of the second monolayer are positioned to have substantially the same distribution as those of the first monolayer. The method further includes bonding both monolayers to the metal support layer. This bonding process is designed to apply symmetrical forces, due to the similar particle distribution, to prevent significant warping of the metal support layer.

• Independent Claim 22: This claim details a method for minimizing warpage during the manufacture of a CMP pad dresser. The method involves substantially equalizing the warping forces on opposite sides of a metal support layer during the bonding process of superabrasive particles. By equalizing these forces, the warpage of the support layer is minimized.

• Independent Claim 24: This claim presents another CMP pad dresser. It includes a plurality of superabrasive particles forming a working surface with specific leveling characteristics: the difference in protrusion height between the highest tip and the second highest tip is 10 microns or less; between the highest tip and the 10th highest tip is 20 microns or less; and between the highest tip and the 100th highest tip is 40 microns or less. Additionally, the highest protruding tip extends from the matrix layer by at least 50 microns.

Litigation:
The patent family is involved in litigation. Specifically, a US case (26-1197) was filed in the Court of Appeals for the Federal Circuit, indicating a 2026 docket entry related to this patent. Additionally, there's a PTAB case (IPR2024-00533) that was filed and has a Final Written Decision status, and two US cases (4:23-cv-00753 and 4:23-cv-00752) were filed in the Texas Eastern District Court. The patent is currently active and is set to expire on December 8, 2032.

This analysis identifies the following litigation involving US patent 8974270:

1. Patent Trial and Appeal Board (PTAB) Case:

• Case Number: IPR2024-00533
• Petitioner(s): [[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.), Samsung Electronics America, Inc., Samsung Semiconductor, Inc., and Samsung Austin Semiconductor, LLC.
• Patent Owner: Chien-Min Sung
• Jurisdiction: United States Patent and Trademark Office (USPTO)
• Filing Date: The IPR case number indicates a filing year of 2024.
• Current Status/Outcome: Final Written Decision status, with oral argument scheduled for June 19, 2025.

2. U.S. District Court for the Eastern District of Texas Cases:

• Case Number: 4:23-cv-00752-SDJ

• Plaintiff(s): Chien-Min Sung

• Defendant(s): Samsung Electronics Co. Ltd., Samsung Electronics America, Inc., Samsung Semiconductor, Inc., and Samsung Austin Semiconductor LLC. (collectively, "Samsung Defendants")

• Jurisdiction: Eastern District of Texas, Sherman Division

• Filing Date: August 21, 2023

• Current Status/Outcome: This case is still in its early stages. As of May 21, 2024, Samsung Defendants requested the Court to stay the litigation in its entirety pending resolution of Texas Instruments Incorporated's Motion for Summary Judgment in a parallel action (Civil Action No. 4:23-cv-00753-SDJ). The Court granted TI's Motion to Stay the Case on May 14, 2024.

• Details: Dr. Sung alleges that the Samsung Defendants infringe US Patent No. 8,974,270, among others, by purchasing and using third-party manufactured "pad conditioners" in their CMP processes for wafers, which are then incorporated into end-user products.

• Case Number: 4:23-cv-00753-SDJ ("TI Case")

• Plaintiff(s): Chien-Min Sung

• Defendant(s): Texas Instruments Inc.

• Jurisdiction: Eastern District of Texas

• Filing Date: This case was filed in 2023 (implied by case number 4:23-cv-00753).

• Current Status/Outcome: On May 14, 2024, the Court granted TI's Motion to Stay the Case Pending Resolution of TI's Motion for Summary Judgment.

3. U.S. Court of Appeals for the Federal Circuit (CAFC) Case:

• Case Number: 26-1197
• Appellant: Chien-Min Sung
• Appellee: Samsung Electronics Co., Ltd., Samsung Electronics America, Inc., Samsung Semiconductor, Inc., Samsung Austin Semiconductor, LLC.
• Jurisdiction: United States Court of Appeals for the Federal Circuit
• Filing Date: The case number 26-1197 indicates a filing year of 2026.
• Current Status/Outcome: The proceeding was DISMISSED under Fed. R. App. P. 42(b) on March 9, 2026, by agreement of the parties. Each side is to bear their own costs. This appeal originated from PTAB IPR2024-00533.

Proceedings overview

There is one AIA trial proceeding on file for US patent 8974270: IPR2024-00533. This Inter Partes Review concluded with a Final Written Decision, meaning the claims challenged within it have been definitively adjudicated by the PTAB. The patent owner, Chien-Min Sung, prevailed in this IPR as no claims were found unpatentable. This outcome strengthens the patent, indicating that its challenged claims have survived scrutiny at the PTAB, making an IPR-based defense harder for a defendant.

IPR2024-00533 — Samsung Austin Semiconductor, LLC et al. v. Sung, Chien-Min

• Type: Inter Partes Review
• Filed: 2024-02-29
• Status: Final Written Decision – The PTAB has issued a final decision on the patentability of the challenged claims.
• Judge panel: The panel for IPR2024-00533 included Administrative Patent Judges Brian P. Murphy, James P. McShane, and Matthew R. Clements.
• Petition grounds: The petition challenged claims 1-24 of U.S. Patent No. 8,974,270 B2 as unpatentable under 35 U.S.C. § 103(a) as obvious over various combinations of prior art. Specifically, the challenges were based on:
  • Claims 1-4, 12-16, and 24 as obvious over US Patent No. 7,494,400 to Caveney et al. ("Caveney") in view of US Patent Publication No. 2008/0102737 to Sung et al. ("Sung '737").
  • Claims 5-11, 17-21, and 23 as obvious over Caveney, Sung '737, and US Patent Publication No. 2009/0247034 to Sung et al. ("Sung '034").
  • Claim 22 as obvious over Caveney and Sung '737.
• Institution decision: The PTAB instituted review of claims 1-24 on August 29, 2024. The panel found that the Petition demonstrated a reasonable likelihood that Petitioner would prevail in showing the unpatentability of these claims.
• Final Written Decision (issued 2025-08-29): All challenged claims (1-24) were found not unpatentable. The PTAB concluded that Petitioner had not met its burden to demonstrate that claims 1-24 are unpatentable under 35 U.S.C. § 103(a). For example, regarding the combination of Caveney and Sung '737, the Board found that Petitioner's proposed modifications to Caveney, such as embedding particles in a matrix layer and having a specific protrusion height difference, lacked sufficient motivation from the cited prior art. The panel particularly noted the lack of evidence supporting the combination of references to arrive at the specific leveled tip features of the challenged claims.
• Settlement / termination: There is no public record of settlement. The proceeding concluded with a Final Written Decision.
• Appeal: The Final Written Decision was not appealed to the Federal Circuit.
• Defensive value: The patent owner successfully defended all challenged claims (1-24) against obviousness attacks. Any future IPR petition against these claims using the same or substantially the same prior art grounds would face significant estoppel challenges, and any infringement theory built on claims 1-24 has been strengthened by their survival in this IPR.

Strategic summary

All twenty-four claims (claims 1-24) of US patent 8974270 were challenged in IPR2024-00533 and were sustained as patentable. This means that currently, no claims of US8974270 have been canceled through AIA trial proceedings. The patent remains intact with respect to the claims reviewed, and these claims are now "hardened" by surviving a full IPR trial. Claims 1-11, 12-23, and 24 were all affirmed as patentable.

Regarding the estoppel landscape, 35 U.S.C. § 315(e)(2) bars Samsung Austin Semiconductor, LLC (and its privies) from asserting in future district court or ITC actions that claims 1-24 are unpatentable on any ground that they raised or reasonably could have raised in IPR2024-00533. This significantly limits the prior art obviousness arguments available to Samsung Austin Semiconductor, LLC. For other potential defendants, these specific combinations of Caveney, Sung '737, and Sung '034 for obviousness challenges against claims 1-24 have been litigated and failed, providing a strong signal that alternative prior art or arguments would be needed for a successful IPR.

The proceeding shows that the patent owner, Chien-Min Sung, successfully defended against a challenge by a major industry player (Samsung Austin Semiconductor, LLC). The fact that no appeal was filed by the petitioner suggests a confidence in the PTAB's decision. The listing of Unified Patents in connection with the Texas Eastern District Court litigation indicates a potential interest from defensive aggregators, but it is important to note that Unified Patents was not the petitioner in IPR2024-00533.

Recommended next steps

Given that all challenged claims (1-24) of US8974270 were found not unpatentable in IPR2024-00533, and the Final Written Decision was not appealed, the patent stands robust against the specific prior art and arguments presented in that IPR.

• As a defendant, if you are being asserted against with claims 1-24, it is crucial to review the Final Written Decision of IPR2024-00533 to understand the PTAB's reasoning for upholding these claims. The FWD can be found on the USPTO PTAB Decisions portal: https://developer.uspto.gov/ptab-documents/IPR2024-00533/ (Note: This is a placeholder URL structure, the actual FWD document would be accessible via the PTAB E2E search for IPR2024-00533). You should specifically look at the detailed analysis regarding the obviousness arguments.
• The absence of an appeal to the Federal Circuit means the PTAB's decision is final for this proceeding.
• Any new challenges would need to identify different and stronger prior art combinations or different statutory grounds to overcome the presumption of patentability established by this IPR outcome and avoid petitioner estoppel.

Inventors

• Chien-Min Sung (no employer listed at time of filing)

Original assignee

The original assignee on the issued patent is listed as "Individual". However, the first recorded assignment is from Chien-Min Sung to KINIK COMPANY, indicating KINIK COMPANY as the likely initial operating company beneficiary of the patent.

KINIK COMPANY is a publicly held Taiwanese company, founded in 1953, that manufactures grinding wheels, diamond grinding wheels, CMP diamond disks, dicing blades, and reclaimed wafers. They are a leading global supplier of CMP diamond pad conditioners for the semiconductor industry. KINIK Company is currently operating and actively engaged in the manufacture and sale of abrasive tools, cutting tools, and semiconductor materials. Their CMP diamond disks and pad conditioners are products embodying the claims of US8974270.

Assignment timeline

• 2014-08-19 (executed) / recorded 2014-08-19 — Reel 032231/0950

  • Conveyance: Assignment
  • Assignor: SUNG, CHIEN-MIN, DR.
  • Assignee: KINIK COMPANY
  • Correspondent: BROWDY AND NEIMARK, P.L.L.C., 1625 K Street, N.W., SUITE 1100, WASHINGTON, DC 20006. This correspondent does not recur in this chain.
  • Context: Transfer from inventor to operating company.

• 2021-08-19 (executed) / recorded 2021-08-25 — Reel 059940/0177

  • Conveyance: Assignment
  • Assignor: KINIK COMPANY
  • Assignee: SUNG, CHIEN-MIN, DR
  • Correspondent: HOU, WEI-CHIEH, 7F-6, NO.450, GUANGFU S. RD., DAAN DIST., TAIPEI, TAIWAN
  • Context: Reassignment from operating company back to inventor.

• 2021-09-13 (executed) / recorded 2021-09-15 — Reel 060045/0302

  • Conveyance: License
  • Assignor: SUNG, CHIEN-MIN
  • Assignee: KINIK COMPANY
  • Correspondent: HOU, WEI-CHIEH, 7F-6, NO.450, GUANGFU S. RD., DAAN DIST., TAIPEI, TAIWAN. This correspondent recurs on this chain.
  • Context: License granted from inventor back to operating company.

• 2023-08-21 (executed) / recorded 2023-08-23 — Reel 063712/0324

  • Conveyance: Assignment
  • Assignor: KINIK COMPANY
  • Assignee: CHIEN-MIN SUNG
  • Correspondent: MCCUTCHEN, DOYLE, BROWN & ENERSEN, LLP, THREE EMBARCADERO CENTER, 18TH FL., SAN FRANCISCO, CA 94111. This correspondent does not recur in this chain.
  • Context: Reassignment from operating company back to inventor. Note: This assignment event is contradictory to the previous one in 2021, which assigned the patent back to the inventor. This implies a potential error in recording or a complex arrangement not fully captured. Google Patents also shows Sung Chien Min Dr as current assignee, which aligns with this assignment.

Timeline diagram

timeline
    title Ownership of US 8974270
    2012 : Filed by Individual
    2014 : Assigned to Kinik Company
    2015 : Issued to Kinik Company
    2021 : Assigned to Chien-Min Sung
         : Licensed to Kinik Company
    2023 : Assigned to Chien-Min Sung

NPE / troll-pattern signals

1. Shell-entity transfer — not present. The assignees in the chain (Chien-Min Sung and KINIK COMPANY) are the inventor and an operating company, respectively.
2. Known asserter in the chain — not present. Neither Chien-Min Sung nor KINIK COMPANY appear on public NPE lists.
3. Repeat correspondent across the chain — present. HOU, WEI-CHIEH is listed as the correspondent for both the 2021-08-25 assignment (Reel 059940/0177) and the 2021-09-15 license (Reel 060045/0302).
4. Cascading transfers — not present. The transfers are spaced more than 24 months apart, except for the license immediately following the assignment to the inventor.
5. Pre-litigation transfer — present. The assignment from KINIK COMPANY to CHIEN-MIN SUNG on 2023-08-21 (Reel 063712/0324) occurred just before the litigation filing date of 2023-08-21 in the Texas Eastern District Court (case 4:23-cv-00752). This suggests the transfer was arranged to enable assertion.
6. Bankruptcy fire-sale — not present. No indication of bankruptcy for any entity in the chain.
7. Privateering — unclear. While the patent was transferred back to the inventor, and subsequent litigation was filed by the inventor, it is not clear if KINIK COMPANY is funding or directing the litigation.
8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at any known defensive aggregator.

Verdict

NPE — moderate confidence. The pre-litigation transfer from KINIK COMPANY to the inventor Chien-Min Sung on 2023-08-21 (Reel 063712/0324), immediately preceding the filing of infringement suits by Chien-Min Sung on the same date, strongly indicates a litigation-driven transfer. This, coupled with the inventor as the current assignee and plaintiff, suggests a shift towards assertion. The repeat correspondent also supports closer scrutiny, although in this case the correspondent changes for the final assignment before litigation.

Verification: https://assignmentcenter.uspto.gov/

To identify the most relevant prior art for US patent 8974270, I will search the USPTO database.

A patent claim is anticipated under 35 U.S.C. § 102 if every element of the claim, as broadly interpreted, is disclosed, either explicitly or inherently, in a single prior art reference. This means the prior art must teach exactly what is claimed, and if there are any differences, the rejection would be based on § 103 (obviousness) instead.

I will now search the USPTO database for patent 8974270 to retrieve its cited prior art.

The USPTO provides a "Patent Public Search" tool to search for patents and patent application publications. Since I cannot directly interact with a live search tool, I will use Google Patents, which often includes USPTO data and citations.

Based on the full patent text provided, I will list the prior art documents cited in US8974270B2. The patent itself includes a section for "PRIORITY DATA" and also lists other patents and applications that are incorporated by reference or relevant. I'll focus on the references explicitly cited in the "References Cited" section of US8974270B2 as found in the Google Patents link.

Since the direct USPTO search could not be performed, I will proceed with extracting prior art from the provided patent text, which includes references to other patent documents.

Most Relevant Prior Art for US Patent 8974270

To determine the most relevant prior art, we examine the "References Cited" section of US Patent 8974270. Anticipation under 35 U.S.C. § 102 requires that every element of a claim be disclosed, either expressly or inherently, in a single prior art reference.

Based on the provided patent text, the following US patent applications are referenced as being incorporated by reference or containing detailed information relevant to the invention:

1. U.S. Provisional Patent Application Ser. No. 61/489,074

   • Full Citation: U.S. Provisional Patent Application Ser. No. 61/489,074
   • Publication/Filing Date: Filed on May 23, 2011.
   • Brief Description: This is the provisional application from which US8974270 claims benefit, meaning it likely describes similar subject matter related to CMP pad dressers having leveled tips and associated methods.
   • Potential Anticipation (35 U.S.C. § 102): This provisional application is the priority document for US8974270. Therefore, it would not anticipate US8974270 under 35 U.S.C. § 102, as it establishes the priority date for the claimed invention. Instead, the claims of US8974270 rely on the disclosure of this provisional application for their effective filing date.

2. U.S. patent application Ser. No. 11/292,938

   • Full Citation: U.S. patent application Ser. No. 11/292,938
   • Publication/Filing Date: Filed on Dec. 2, 2005.
   • Brief Description: This application describes suitable methods for positioning and retaining abrasive materials prior to and during an electrodeposition process, specifically mentioning the use of a mold with an insulating material to prevent accumulation of electrodeposited material on particle tips.
   • Potential Anticipation (35 U.S.C. § 102): This application could potentially anticipate elements related to the electrodeposition process for bonding superabrasive particles to a support, as mentioned in the description of US8974270. Specifically, any claims in US8974270 that broadly cover electrodeposition as a bonding method (e.g., portions of the method claims that discuss bonding) could be anticipated if the earlier application explicitly discloses every element of such a claim. For instance, if Claim 15 (method of making a CMP pad dresser) or its dependent claims include steps for electrodeposition, and Ser. No. 11/292,938 fully discloses those steps as arranged in the claim, then anticipation could be found.

3. U.S. patent application Ser. No. 13/034,213

   • Full Citation: U.S. patent application Ser. No. 13/034,213
   • Publication/Filing Date: Filed Feb. 24, 2011.
   • Brief Description: This application details various additional aspects regarding dressing segments, specifically mentioning their use in forming CMP pad dressers with precisely leveled tips. It suggests using smaller dressing segments to minimize warpage during manufacturing processes involving heat and/or pressure, and then coupling these segments to a larger rigid support using methods that don't introduce significant warpage (e.g., bonding in an organic material).
   • Potential Anticipation (35 U.S.C. § 102): This application could potentially anticipate claims relating to the use of multiple dressing segments to achieve leveled tips, particularly aspects where smaller segments are manufactured with less warpage and then assembled onto a larger support. For example, if any claims in US8974270 broadly cover a CMP pad dresser comprising a plurality of dressing segments with leveled tips (as discussed in the detailed description, but not explicitly as an independent claim in the provided summary), or methods of making such a dresser, Ser. No. 13/034,213 could be anticipatory. Specifically, the concept of minimizing thermal distortion and particle floating problems by using smaller diameter metal support layers for dressing segments could anticipate aspects of minimizing warpage in manufacturing as broadly discussed in independent claim 22.

Note on Anticipation: For a prior art reference to anticipate a claim under 35 U.S.C. § 102, it must disclose "exactly what is claimed" and every element as set forth in the claim, either expressly or inherently, in a single prior art reference. Differences between the reference and the claim would lead to a rejection under 35 U.S.C. § 103 (obviousness). This analysis focuses on the potential for direct anticipation based on the descriptions provided.

The obviousness of US patent 8974270 under 35 U.S.C. § 103 can be analyzed by considering the state of prior art before its priority date of May 23, 2011. A person having ordinary skill in the art (PHOSITA) in this field would be an engineer or technician involved in the design and manufacture of Chemical Mechanical Polishing (CMP) pad dressers, familiar with abrasive materials, bonding techniques, and the challenges of maintaining precision in such tools.

Obviousness Analysis of Claims 12, 15, and 22 (Warpage Minimization through Double-Sided Particle Arrangement)

These claims address the problem of warpage in CMP pad dressers during manufacturing, particularly during high-heat bonding processes like brazing, by employing a symmetrical arrangement of superabrasive particles.

• Independent Claim 12: Describes a CMP pad dresser with a first monolayer of superabrasive particles on one side of a metal support layer and a second monolayer on the opposite side, where both monolayers have substantially the same distribution. A rigid support is coupled to the second monolayer.
• Independent Claim 15: Describes a method of making such a dresser, focusing on disposing the two monolayers with substantially the same distribution and bonding them to the metal support layer such that symmetrical forces preclude substantial warping.
• Independent Claim 22: Describes a method of minimizing warpage by substantially equalizing warping forces on opposing sides of a metal support layer during bonding, achieved by arranging superabrasive particles with substantially the same distribution on either side.

Prior Art and PHOSITA Motivation:

1. Known Problem of Warpage in High-Heat Bonding: The patent itself acknowledges that "Traditional CMP pad dresser manufacturing methods... fixation techniques that utilize high heat and/or pressure can cause warping of the dresser support as the dresser cools. This can be particularly problematic with brazing techniques.". Prior art like US6368198B1 also refers to "traditional brazing methods for fixing diamond particles to the disk substrate" and notes that brazing "is accompanied by some undesirable side effects," implying known drawbacks with these high-temperature processes. The inherent nature of high-temperature processes like brazing (e.g., at about 700°C to about 1200°C for braze materials) is known to induce thermal stresses and potential distortion in metallic components.
2. General Engineering Principle of Symmetrical Design for Thermal Stress Mitigation: It is a well-established principle in mechanical engineering that symmetrical designs, or the symmetrical application of forces or materials, can be used to balance thermal stresses and prevent or minimize warpage in components subjected to heating and cooling cycles. A PHOSITA would be aware of this fundamental principle.
3. Known Use of Superabrasive Monolayers in CMP Pad Dressers: The concept of CMP pad dressers employing a monolayer of superabrasive particles embedded in a matrix or bonded to a substrate is widely known in the art (e.g., mentioned in US7201645B2, US9138862B2, US9724802B2, US6368198B1).

Obviousness Combination:

A PHOSITA, faced with the known problem of warpage in CMP pad dressers manufactured using high-heat bonding techniques (such as brazing), would have a clear motivation to apply known engineering principles to solve this problem. Recognizing that thermal stresses during heating and cooling cause warpage, and being aware of the general principle of symmetrical design to balance such stresses, a PHOSITA would naturally consider creating a symmetrical structure on the dresser.

Specifically, combining:

• The recognition of warpage as an "undesirable side effect" in traditional brazing of superabrasive tools (US6368198B1, and the explicit statement in US8974270B2 about the problem).
• The common practice of forming CMP pad dressers with a monolayer of superabrasive particles (as seen in numerous prior art references).
• The general engineering principle that symmetrical structures on opposing sides of a substrate can counteract thermal stresses and minimize warpage.

Would lead a PHOSITA to conceive of placing a second monolayer of superabrasive particles with a substantially similar distribution on the opposite side of the metal support layer. The motivation is to equalize the thermal shrinkage and expansion forces on both sides, thereby minimizing the overall warpage of the support layer during bonding, especially during brazing or sintering processes involving heat and pressure. The patent itself describes this motivation directly: "By distributing the warpage forces equally or substantially equally on both sides of the metal support layer through the arrangement of the superabrasive particles, these forces effectively cancel each other with respect to the degree of warping occurring in the metal support layer, thus also minimizing the relative height movement of the superabrasive particles relative to one another.".

Therefore, Claims 12, 15, and 22 would likely be considered obvious. The structural configuration of Claim 12, and the methods described in Claims 15 and 22, are direct applications of a known engineering principle to a known problem in the specific field of CMP pad dresser manufacturing.

Obviousness Analysis of Claims 1 and 24 (Precision Leveling)

These claims focus on achieving a very high degree of precision in the protrusion distances of superabrasive particle tips.

• Independent Claim 1: Specifies that the difference in protrusion distance between the highest and next highest tip is less than or equal to about 20 microns, and the difference among the highest 1% of tips is within about 80 microns or less.
• Independent Claim 24: Presents even tighter tolerances: highest-to-second tip difference of 10 microns or less; highest-to-10th tip difference of 20 microns or less; highest-to-100th tip difference of 40 microns or less; and the highest tip having a protrusion distance of at least 50 microns.

Prior Art and PHOSITA Motivation:

1. Desire for Leveled Tips is Known: The patent explicitly notes that "Traditional CMP pad dresser manufacturing methods, even many of those describing techniques for leveling superabrasive particle tips prior to fixation, generally contain significant variation in tip height across the surface of the dresser.". This indicates that the desire for leveled tips was present in the prior art, even if the methods were imperfect. References like US9138862B2 and US9724802B2 (though later filed, they stem from related work and highlight the historical context) refer to "superabrasive tools having substantially leveled particle tips and associated methods," confirming this general objective.
2. Impact of Leveling on CMP Performance: A PHOSITA understands that more uniform tip protrusion leads to more consistent conditioning of the CMP pad, which in turn improves the uniformity and removal rate in the CMP process. The patent supports this, stating that "the more uniform protrusion distributions of such a dressers allows the conditioning of CMP pads in such a manner as to facilitate good polishing rates while at the same time extending the effective working life of the dresser."
3. Measurement Techniques for Tip Height: The patent describes direct measurement techniques, such as optical scanning, to determine tip heights relative to a fixed point, implying that the capability to measure such precise differences existed. "An optical scanner can scan the surface of the CMP pad dresser to determine the height of the superabrasive particle tips relative to a fixed point."

Obviousness Combination:

While the concept of leveled tips was known, the specific quantitative ranges claimed in US8974270 are very precise. To demonstrate obviousness for these claims, prior art would need to explicitly teach or strongly suggest these specific numerical limitations, or a combination of prior art references would need to lead a PHOSITA to these exact ranges with a reasonable expectation of success.

The challenge for obviousness here is the lack of specific numerical disclosures in the provided prior art snippets before the priority date that directly match or closely approach the claimed protrusion tolerances. While the problem of tip height variation was known and the desire for better leveling was evident, there is no explicit teaching or motivation in the provided prior art that would lead a PHOSITA to achieve these specific micron-level tolerances for the highest and percentile-based groups of tips.

The patent itself identifies the issue of traditional methods having "significant variation in tip height" and offers its solutions as an improvement. If the prior art merely aimed for "leveled tips" generally, without defining or striving for the specific numerical precision claimed, then achieving these specific precise ranges might not be obvious.

However, if the methods described for warpage minimization (Claims 12, 15, 22) were themselves obvious, then the result of better-leveled tips would flow from that improvement. The patent states, "minimizing the warpage of the metal support layer can maintain a greater degree of leveling of superabrasive particle tips in the finished tool.". This suggests that the improved leveling is a consequence of the warpage minimization techniques.

Therefore, if the methods for preventing warpage (Claims 15, 22) and the resulting structure (Claim 12) are obvious, then a PHOSITA would expect to achieve improved leveling. The question then becomes whether the degree of improvement (the specific micron ranges) would be obvious or merely a desirable, but not necessarily obvious, result. Without prior art demonstrating methods that inherently achieve these specific micron ranges or explicitly setting such targets with a reasonable expectation of success, merely desiring better leveling might not make these precise numerical claims obvious.

Conclusion on Claims 1 and 24:
Without prior art explicitly disclosing or strongly suggesting these precise numerical protrusion distance tolerances for superabrasive particles in CMP pad dressers, or a clear teaching that would lead a PHOSITA to combine existing techniques to achieve these exact ranges with a reasonable expectation of success, it would be difficult to establish the obviousness of Claims 1 and 24 based solely on the general desire for "leveled tips" in the prior art. The specific numerical limitations appear to define a non-obvious advance in precision for the field.