Rohm and Haas Electronic Materials CMP Holdings, Inc. (formerly known as Rodel Holdings, Inc.) v NexPlanar Corporation and another

• Jurisdiction: Singapore
• Judge: George Wei J
• Judgment Date: 08 December 2017
• Neutral Citation: [2017] SGHC 310
• Published date: 27 June 2020
• Date: 08 December 2017
• Year: 2017
• Hearing Date: 08 March 2017,17 January 2017,23 January 2017,25 January 2017,24 January 2017,19 January 2017,13 January 2017,16 January 2017,20 January 2017,18 January 2017,12 January 2017
• Plaintiff Counsel: Tan Tee Jim SC, Christopher de Souza, Darrell Wee Jiawei and Jasper Nathanael Lim Shih Hao (Lee & Lee)
• Defendant Counsel: Low Chai Chong, Long Ai Ming, Alvin Lim Jun Hao and Kenneth Fok Quan Wei (Dentons Rodyk & Davidson LLP)
• Court: High Court (Singapore)
• Citation: [2017] SGHC 310
• Docket Number: Suit No 470 of 2012

George Wei J: Introduction

This suit involves a patent for a polishing pad used in the field of semiconductor manufacturing. The plaintiff alleges that the defendants infringed its patent by selling and dealing with certain polishing pads manufactured by the first defendant. In their defence, the defendants deny that their actions amount to infringement of the plaintiff’s patent, and further contend that the plaintiff’s patent is invalid for lack of novelty, lack of inventive step and insufficiency of particulars. The defendants also counterclaim for the revocation of the patent.

The trial of this suit was heard over ten days in January 2017, with closing submissions filed in March 2017. I now deliver my judgment.

Background facts

The plaintiff, Rohm and Haas Electronic Materials CMP Holdings, Inc (formerly known as Rodel Holdings, Inc) (“the Plaintiff”), is a company incorporated in the United States of America and the subsidiary of Dow Chemical Company (“Dow Chemical”). It was the registered proprietor of Singapore Patent No 43335, in respect of a “Polymeric Polishing Pad Containing Hollow Polymeric Microelements” (“the Patent”)¹, which expired on 2 August 2013.²

While I will go into greater technical detail later in my judgment, at this juncture, I will first provide a simple description of the Patent and a brief explanation of the context in which the claimed invention is used. The claimed invention relates to the field of semiconductor manufacturing. Semiconductors are built on thin round discs or wafers, commonly made of silicon. One of the stages in wafer manufacturing is known as “chemical mechanical polishing / planarisation” (“CMP”), which refers to the process of smoothening a surface by means of a combination of chemical and mechanical forces. In the CMP process, the wafer is pressed against a polishing pad, and both the wafer and the pad rotate while in contact with each other. At the same time, an abrasive and corrosive chemical slurry is dispensed onto the polishing pad to aid in the smoothening of the wafer.³

The claimed invention is a polishing pad used to polish or planarise the surface of an electronic substrate such as a wafer. This pad includes a polymeric matrix or substrate that is embedded with hollow polymeric microelements. The pad comprised a “work surface” with microelements that come into direct contact with the work-piece, as well as another “subsurface” of microelements. The microelements at the work surface are less rigid than those embedded in the subsurface. As the work surface wears out, the subsurface becomes the new work surface. The regeneration of the subsurface as the new work surface allows for a more consistent and even polishing of the wafer.⁴

The Patent consists of 21 claims, of which only eight have been put in issue in the present case (“the asserted claims”). What this means is that only eight claims are relied on by the Plaintiff. The table below sets out these eight asserted claims in full, according to the patent specification filed with the Intellectual Property Office of Singapore on 23 February 1996⁵ and amended most recently on 23 August 1999:⁶

Claim No	Description
1	A polishing pad for polishing or planarizing a surface of an electronic substrate, said pad comprising a polymeric matrix impregnated with a plurality of hollow, flexible, organic polymeric microelements, said pad having a work surface and a subsurface proximate to said work surface, one portion of said polymeric microelements being at said work surface and exposed to a working environment including a polishing slurry, another portion of said polymeric microelements being embedded within said subsurface of said pad that is not exposed to said working environment, said work surface of said pad is relatively softer than said subsurface as a result of said exposure of said one portion of said polymeric microelements at said work surface to said working environment, and said subsurface becomes said relatively softer work surface during wear of said pad when said polymeric microelements are exposed to said working environment.
2	A pad according to claim 1, wherein said polymeric microelements are substantially uniformly distributed throughout said polymeric matrix.
3	A pad according to claim 1, wherein said polymeric matrix comprises a urethane polymer.
8	A pad according to claim 1, wherein said polymeric microelements have a mean diameter less than about 150 µm.
10	A pad according to claim 1, wherein said polymeric microelements are spaced apart by about 1 µm to about 100 µm.
11	A pad according to claim 1, wherein at least some of said polymeric microelements are generally spherical in shape.
12	A pad according to claim 1, wherein at least some of said polymeric microelements have permeable shells so that said hollow microelements may be rendered open to said working environment.
21	A polishing pad for polishing or planarizing a surface of an electronic substrate, said pad comprising a polymeric matrix impregnated with a plurality of hollow, flexible, organic polymeric microelements, said pad having a texturized work surface and a subsurface proximate to said work surface, one portion of said polymeric microelements being at said work surface and exposed to a working environment including a polishing slurry, another portion of said polymeric microelements being embedded within said subsurface of said pad that is not exposed to said working environment, said texturized work surface of said pad is relatively softer than said subsurface as a result of said exposure of said one portion of said polymeric microelements at said work surface to said working environment, and said subsurface becomes said relatively softer work surface during wear of said pad when said polymeric microelements are exposed to said working environment.

Out of the asserted claims, it is undisputed that only claim 1 and claim 21 are independent claims, while claims 2, 3, 8, 10, 11 and 12 relate back to claim 1. Claim 21 differs from claim 1 only in that the “work surface” is described as a “texturized work surface”.

On 19 September 2000, the Plaintiff obtained a grant of the Patent under s 29(1)(c) of the Patents Act (Cap 221, 1995 Rev Ed) by relying on the final search and examination results of its corresponding US patent, US Patent No 5,578,362 (“the US Patent”).⁷ The asserted claims of the Patent set out in the table at [6] above are identical to those in the US Patent. The wording of the US Patent only differs slightly from that of the Patent for claims 13 and 18 which are not asserted, and these differences are not material or significant.⁸ The Plaintiff claimed priority from the date of its application to the US Patent and Trademark Office for the US Patent, 19 August 1992.⁹

The first defendant, NexPlanar Corporation (“the 1st Defendant”), is a US-incorporated company in the business of designing and manufacturing CMP pads. The second defendant, Wah Lee Tech (Singapore) Pte Ltd (“the 2nd Defendant”), is a locally-incorporated company which imports and purchases CMP pads from suppliers such as the 1st Defendant and resells the CMP pads to its customers in Singapore. I will refer to the 1st and 2nd Defendants collectively as “the Defendants”.¹⁰

The Plaintiff’s case

On 5 June 2012, the Plaintiff commenced the present suit against the Defendants. According to the Plaintiff, certain CMP pads manufactured and sold by the 1st Defendant infringed the asserted claims of the Patent. The CMP pads in question (“the NexPlanar Pads”) corresponded to twelve of the 1st Defendant’s pad models, namely, “NEX4-6035-30S”, “NEXX-0901”, “NEXX-09NH-30S-25-70TS-4CF”, “NEXX-09NP-30S-25-70TS-4CF”, “NEXX-09V1”, “E7980-30S-25-70TS-4CF”, “NEXX-09P6-30S”, “NEXX-09P7-30S w/ sub-pad 4”, “NEXPLANAR PAD-NEXX-09NF-30S-25”, “NEXPLANAR PAD NEXX-09NP-30S-25-70TS-40F”, “NEXX-09V1-30S” and “Nexx-09NH”.¹¹

The Plaintiff alleges that the following acts by the Defendants between 2010 and 2012 constitute infringement of the Patent:¹² the 1st Defendant’s sale of (or offer to sell) the NexPlanar Pads to the 2nd Defendant around late 2010 to the first quarter of 2012, for the purpose of the 2nd Defendant’s sale, offer to sell, importation, use or keeping of the NexPlanar Pads; the 2nd Defendant’s importation, use or keeping of the NexPlanar Pads around late 2010 to the first quarter of 2012; and the 2nd Defendant’s sale of (or offer to sell) the NexPlanar Pads to a company known as United Microelectronic Corporation (“United Microelectronic”) between late 2010 and the first quarter of 2012. The Plaintiff further asserts that the 1st Defendant directed, authorised, procured, assisted or enabled the 2nd Defendant to infringe the Patent, and/or acted in concert with the 2nd Defendant pursuant to a common design to infringe the Patent.¹³ No infringement action was brought against United Microelectronics.

The Plaintiff thus claims against the Defendants for: a declaration that the Patent was valid and that it was infringed by the Defendants; an injunction to restrain the Defendants from making, disposing of, offering to dispose of, using, importing and/or keeping products which infringe the Patent; an injunction to restrain the 1st Defendant from: directing, authorising, procuring, assisting or enabling the 2nd Defendant to infringe the Patent; and/or acting in concert with the 2nd Defendant in furtherance of the said infringement pursuant to a common design; an inquiry as to damages or an account of profits made by the Defendants, and an order for payment for all sums found to be due upon making the inquiry or account; an order for the delivery up and/or destruction of all infringing products which are in the possession, custody or control of the Defendants; full discovery of all matters relating...