Superlattice strain relief layer for semiconductor devices

US7547925B2 · kind B2 · utility

Assignee

• Palo Alto Research Center Incorporated · US

Inventors

• William S. Wong · Redwood City, US
• Michael A. Kneissl · Berlin, DE
• Zhihong Yang · San Jose, US
• Mark R. Teepe · Menlo Park, US
• Cliff Knollenberg · Mountain View, US

Key dates

• Filing date: Feb 17, 2006
• Grant date: Jun 16, 2009
• Expiry date: Jan 5, 2027

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10H20/825
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A GaN/AlN superlattice is formed over a GaN/sapphire template structure, serving in part as a strain relief layer for growth of subsequent layers (e.g., deep UV light emitting diodes). The GaN/AlN superlattice mitigates the strain between a GaN/sapphire template and a multiple quantum well heterostructure active region, allowing the use of high Al mole fraction in the active region, and therefore emission in the deep UV wavelengths.