Abstract: A light-emitting device, such as a light-emitting diode (LED), is grown on a substrate including a ZnO-based material. The structure includes a plurality of semiconductor layers and an active layer disposed between the plurality of semiconductor layers. The device is removed from the substrate or the substrate is substantially thinned to improve light emission efficiency of the device.
Type:
Application
Filed:
September 21, 2009
Publication date:
June 3, 2010
Applicant:
LumenZ LLC
Inventors:
Gianni TARASCHI, Bunmi T. ADEKORE, Jonathan PIERCE
Abstract: A p-type ZnO-based II-VI compound semiconductor layer has silver, potassium and/or gold dopants therein at a net p-type dopant concentration of greater than about 1×1017 cm?3. A method of forming the layer includes using an atomic layer deposition (ALD) technique. This technique includes exposing a substrate to a combination of gases: a first reaction gas containing zinc at a concentration that is repeatedly transitioned between at least two concentration levels during a processing time interval, a second reaction gas containing oxygen and a p-type dopant gas containing at least one p-type dopant species selected from a group consisting of silver, potassium and gold. A concentration of oxygen in the second reaction gas may also be repeatedly transitioned between at least two concentration levels.
Type:
Grant
Filed:
October 19, 2006
Date of Patent:
May 25, 2010
Assignees:
North Carolina State University, LumenZ, LLC
Inventors:
Bunmi T. Adekore, Jonathan M. Pierce, Robert F. Davis, George B. Kenney
Abstract: A light-emitting device, such as a light-emitting diode (LED), includes a substrate including a ZnO-based material, and a structure disposed on a first side of the substrate. The structure includes a plurality of semiconductor layers and an active layer disposed between the plurality of semiconductor layers. The device further includes at least one textured light emission surface arranged to extract at least some light generated within the device.
Type:
Application
Filed:
September 18, 2009
Publication date:
May 13, 2010
Applicant:
LUMENZ LLC
Inventors:
Bunmi T. ADEKORE, Jonathan PIERCE, George B. KENNEY, Gianni TARASCHI
Abstract: Devices and methods of fabrication of ZnO based single and multi-junction photovoltaic cells are disclosed. ZnO based single and multijunction photovoltaic cells, and other optoelectronic devices include p-type, n-type, and undoped materials of ZnxA1-xOyB1-y, wherein the alloy composition A and B, expressed by x and y, respectively, varies between 0 and 1. Alloy element A is selected from related elements including Mg, Be, Ca, Sr, Cd, and In and alloy element B is selected from a related elements including Te and Se. The selection of A, B, x and y, allows tuning of the material's band gap. The band gap of the material may be selected to range between approximately 1.4 eV and approximately 6.0 eV. ZnxA1-xOyB1-y based tunnel diodes may be formed and employed in ZnxA1-xOyB1-y based multi-junction photovoltaic devices. ZnxA1-xOyB1-y based single and multi-junction photovoltaic devices may also include transparent, conductive heterostructures and highly doped contacts to ZnO based substrates.