Trustees of Boston University v. Everlight Electronics Co.

896 F.3d 1357
CourtCourt of Appeals for the Federal Circuit
DecidedJuly 25, 2018
Docket2016-2576; 2016-2577; 2016-2578; 2016-2579; 2016-2580; 2016-2581; 2016-2582; 2016-2591; 2016-2592; 2016-2593; 2016-2594; 2016-2595
StatusPublished
Cited by21 cases

This text of 896 F.3d 1357 (Trustees of Boston University v. Everlight Electronics Co.) is published on Counsel Stack Legal Research, covering Court of Appeals for the Federal Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Trustees of Boston University v. Everlight Electronics Co., 896 F.3d 1357 (Fed. Cir. 2018).

Opinion

Prost, Chief Judge.

Plaintiff-cross-appellant Trustees of Boston University ("BU") sued defendants-appellants Everlight Electronics Co., Ltd. and Everlight Americas, Inc. (together, "Everlight"); Epistar Corp. ("Epistar"); Lite-On Inc., Lite-On Service USA, Inc., Lite-On Technology Corp., and Lite-On Trading USA, Inc. (together, "Lite-On") (collectively, "Defendants") for infringing BU's U.S. Patent No. 5,686,738 (the " '738 patent"). A jury found that Defendants infringed the '738 patent and failed to prove the patent's invalidity.

Defendants then renewed their motion for judgment as a matter of law ("JMOL") that the '738 patent is invalid for not meeting the enablement requirement of 35 U.S.C. § 112 . The district court denied Defendants' motion, and Defendants appeal that denial. BU cross-appeals on other issues.

We reverse because the asserted claim of the '738 patent is not enabled as a matter of law. We dismiss BU's cross-appeal as moot.

*1359 BACKGROUND

I

Light-emitting diodes ("LEDs") are semiconductor devices that emit light when an electric current is applied. They provide illumination in products such as printers, phones, and televisions. LEDs typically consist of multiple layers, including a substrate, an n-type semiconductor layer, and a p-type semiconductor layer. 1

These layers are solid-state materials, which generally have one of three types of crystal lattice structures: (1) monocrystalline, a single-crystalline structure with long-range order; (2) polycrystalline, where multiple smaller crystal structures with short-range order combine to form a single structure that lacks long-range order; and (3) a mixture of polycrystalline and amorphous regions-i.e., non-crystal regions with inconsistent spacing among atoms. Solid-state materials can also just be amorphous.

Epitaxy is a process used to fabricate semiconductor layers. During epitaxy, molecules of a semiconductor material are deposited on a substrate, and the deposited layer attempts to mimic the substrate's crystal lattice structure as the layer grows. Ideally, the lattice structures of the substrate and the deposited semiconductor layer will be the same; otherwise, the deposited molecules will strain against their own structure when attempting to mimic the substrate's structure, creating a problem known as lattice mismatch. Such mismatch introduces stress into the growing layer and can create defects in that layer.

Gallium nitride ("GaN") is a semiconductor that emits blue light in LEDs. Fabricating monocrystalline GaN layers (or "films") has proved difficult because of the lack of available substrates with a matching lattice structure. For example, although sapphire has properties that make it a good substrate candidate, GaN films grown directly on sapphire were defective because of the differences in the materials' lattice structures.

The '738 patent relates to the preparation of monocrystalline GaN films via molecular beam epitaxy. '738 patent col. 1 ll. 12-15. It addresses the GaN lattice-mismatch problem with a two-step growth process. See id. at col. 2 ll. 14-17 ("A film is epitaxially grown in a two step process comprising a low temperature nucleation step and a high temperature growth step."). In the first step, the substrate is exposed to gallium and nitrogen at a temperature between 100 °C and 400 °C. Id. at col. 2 ll. 17-19; see id. at col. 4 ll. 31-34. An amorphous film of GaN-the "buffer layer"-grows on the substrate as GaN is deposited. Id. at col. 2 ll. 40-41, col. 4 ll. 31-36.

In the second step, temperature is raised to between 600 °C and 900 °C in order to crystallize the amorphous buffer layer. Id. at col. 2 ll. 42-43, col. 4 ll. 34-36 ("As the temperature increases to 600 °C[ ], the amorphous film crystallizes."). Monocrystalline GaN can then be grown on the crystallized buffer layer. Id. at col. 4 ll. 36-37 ("Any further growth takes place on the crystallized GaN buffer layer."), col. 4 ll. 47-49 ("The growth layer of GaN 'recognizes' the GaN buffer layer ... on which it can grow without defects."); see id. at col. 2 ll. 41-45 ("The amorphous film can be crystallized by heating at 600°-900°

*1360 C[ ] .... Subsequent treatment at higher temperatures, preferably 600°-900° C[ ], results in the epitaxial growth of monocrystalline near-intrinsic GaN film."), col. 4 ll. 25-27 (explaining that, after "ensur[ing] that the GaN buffer layer had crystallized," the "Ga shutter was opened once again to grow the GaN monocrystalline film").

Claim 19 was the only claim tried to the jury. It reads:

A semiconductor device comprising:
a substrate, said substrate consisting of a material selected from the group consisting of (100) silicon, (111) silicon, (0001) sapphire, (11-20) sapphire, (1-102) sapphire, (111) gallium aresenide, (100) gallium aresenide, magnesium oxide, zinc oxide and silicon carbide;
a non-single crystalline buffer layer , comprising a first material grown on said substrate, the first material consisting essentially of gallium nitride; and
a growth layer grown on the buffer layer, the growth layer comprising gallium nitride and a first dopant material.

'738 patent col. 7 l. 42-col. 8 l. 9 (key limitations emphasized).

II

The district court construed two terms relevant here. First, it construed "grown on" to mean "formed indirectly or directly above." J.A. 246. Under this construction, claim 19's growth layer and buffer layer do not have to be in direct contact; there can be intervening layers between them.

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Bluebook (online)
896 F.3d 1357, Counsel Stack Legal Research, https://law.counselstack.com/opinion/trustees-of-boston-university-v-everlight-electronics-co-cafc-2018.