The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 30, 2018
Filed:
Dec. 15, 2010
Nelson Tansu, Bethlehem, PA (US);
Hongping Zhao, Bethlehem, PA (US);
Guangyu Liu, Bethlehem, PA (US);
Gensheng Huang, Bethlehem, PA (US);
Nelson Tansu, Bethlehem, PA (US);
Hongping Zhao, Bethlehem, PA (US);
Guangyu Liu, Bethlehem, PA (US);
Gensheng Huang, Bethlehem, PA (US);
Lehigh University, Bethleham, PA (US);
Abstract
A symmetrical quantum well active layer provides enhanced internal quantum efficiency. The quantum well active layer includes an inner (central) layer and a pair of outer layers sandwiching the inner layer. The inner and outer layers have different thicknesses and bandgap characteristics. The outer layers are relatively thick and include a relatively low bandgap material, such as InGaN. The inner layer has a relatively lower bandgap material and is sufficiently thin to act as a quantum well delta layer, e.g., comprising approximately 6 Å or less of InN. Such a quantum well structure advantageously extends the emission wavelength into the yellow/red spectral regime, and enhances spontaneous emission. The multi-layer quantum well active layer is sandwiched by barrier layers of high bandgap materials, such as GaN.