Dislocation reduction in non-polar III-nitride thin films

US8809867B2 · kind B2 · utility

Assignee

• The Regents of the University of California · US

Inventors

• Michael D. Craven · Goleta, US
• Steven P. DenBaars · Goleta, US
• James S. Speck · Fremont, US
• Shuji Nakamura · Goleta, US

Key dates

• Filing date: Sep 10, 2007
• Grant date: Aug 19, 2014
• Expiry date: Oct 5, 2027

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/02647
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Lateral epitaxial overgrowth of non-polar III-nitride seed layers reduces threading dislocations in the non-polar III-nitride thin films. First, a thin patterned dielectric mask is applied to the seed layer. Second, a selective epitaxial regrowth is performed to achieve a lateral overgrowth based on the patterned mask. Upon regrowth, the non-polar III-nitride films initially grow vertically through openings in the dielectric mask before laterally overgrowing the mask in directions perpendicular to the vertical growth direction. Threading dislocations are reduced in the overgrown regions by (1) the mask blocking the propagation of dislocations vertically into the growing film and (2) the bending of dislocations through the transition from vertical to lateral growth.