Applied Materials, Inc. v. Demaray LLC

Background

Applied Materials, Inc. sued Demaray LLC seeking a declaration that Applied’s products did not infringe U.S. Patent Nos. 7,381,657 and 7,544,276. Demaray countersued for declarations of patent validity and infringement, and Applied asserted a counterclaim seeking a declaration that the patents were invalid. The opinion addressed Applied’s motion for summary judgment of non-infringement.

The patents concern systems and methods for depositing thin films, including films used in semiconductor and optical devices. The relevant claims require a “pulsed DC power supply,” which the court had construed to mean a supply providing direct-current power that oscillates between positive and negative voltages. The claims also require that the component supply alternating positive and negative voltages to the target.

Literal Infringement

For literal infringement, every claim limitation must be present in the accused product. The court found no genuine dispute that the direct-current power supplies in Applied’s accused Cirrus chambers never provide positive voltage and do not themselves produce power that oscillates between positive and negative voltages. The court rejected Demaray’s arguments that the power supplies could satisfy the limitation by working with other system components or by producing brief voltage spikes during arc suppression.

Because the Cirrus chambers lacked a “pulsed DC power supply” as the court had construed that term, the court found that they did not literally infringe the patents. The court did not address the separate requirement concerning alternating positive and negative voltages at the target.

Doctrine of Equivalents and Prosecution History

The doctrine of equivalents can sometimes treat an accused product as infringing even when it does not literally meet a claim limitation. Applied argued that prosecution-history estoppel barred Demaray from using that theory. Prosecution-history estoppel can prevent a patent owner from later asserting subject matter that the patent applicant clearly and unmistakably surrendered while obtaining the patent.

The court concluded that the applicants’ statements distinguishing prior art could reasonably be understood as focusing on whether the voltage at the target remained negative, rather than solely on whether the power supply itself produced positive voltage. Because there were factual disputes about whether the combined direct-current and radio-frequency power supplies caused the voltage at the target to become positive, Applied had not shown a clear and unmistakable surrender of the relevant subject matter.

Disposition

The court GRANTED IN PART and DENIED IN PART Applied’s motion for summary judgment. It granted the motion on literal infringement, finding that Applied’s products did not literally infringe the patents. It denied the motion on prosecution-history estoppel, concluding that Applied had not shown that estoppel barred Demaray from asserting infringement under the doctrine of equivalents.