III-nitride light emitting devices grown on templates to reduce strain
US7534638B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2006 |
| Grant date | May 19, 2009 |
| Priority date | — |
| Expiry date | Jan 11, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/825
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In a III-nitride light emitting device, the device layers including the light emitting layer are grown over a template designed to reduce strain in the device, in particular in the light emitting layer. Reducing the strain in the light emitting device may improve the performance of the device. The template may expand the lattice constant in the light emitting layer over the range of lattice constants available from conventional growth templates. Strain is defined as follows: a given layer has a bulk lattice constant abulk corresponding to a lattice constant of a free standing material of a same composition as that layer and an in-plane lattice constant ain-plane corresponding to a lattice constant of that layer as grown in the structure. The amount of strain in a layer is |(ain-plane−abulk)|/abulk. In some embodiments, the strain in the light emitting layer is less than 1%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.