Patents by Inventor Steven D. Lester
Steven D. Lester has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 9324915Abstract: A light-emitting device includes first and second semiconductor layers and a light-emitting layer between the first and second semiconductor layers. The light-emitting device also includes an improved electrode structures.Type: GrantFiled: January 8, 2014Date of Patent: April 26, 2016Assignee: Kabushiki Kaisha ToshibaInventors: Steven D. Lester, Chao-Kun Lin
-
Publication number: 20150382410Abstract: A light source and method for making the same are disclosed. The light source includes a plurality of Segmented LEDs connected in parallel to a power bus and a controller. The power bus accepts a variable number of Segmented LEDs. The controller receives AC power and provides a power signal on the power bus. Each Segmented LED is characterized by a driving voltage that is greater than 3 times the driving voltage of a conventional LED fabricated in the same material system as the Segmented LED. The number of Segmented LEDs in the light source is chosen to compensate for variations in the light output of individual Segmented LEDs introduced by the manufacturing process. In another aspect of the invention, the number of Segmented LEDs connected to the power bus can be altered after the light source is assembled.Type: ApplicationFiled: June 26, 2015Publication date: December 31, 2015Inventors: Ghulam HASNAIN, Syn-Yem HU, Steven D. LESTER
-
Publication number: 20150380609Abstract: A laser apparatus may comprise: a substrate having a first surface and a second surface opposite to the first surface; a light emitting region formed on the first surface of the first substrate, the light emitting region including a p-type semiconductor layer and an n-type semiconductor layer; a p-contact layer formed on the p-type semiconductor layer; an n-contact layer formed on the n-type semiconductor layer; a sub-mount formed on the p-contact layer and the n-contact layer, the sub-mount including a first patterned dielectric coating layer formed on the p-contact layer and a reflector formed on the patterned dielectric coating layer.Type: ApplicationFiled: September 2, 2015Publication date: December 31, 2015Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Steven D. Lester
-
Publication number: 20150340554Abstract: A light source and method for making the same are disclosed. The light source includes a conducting substrate, and a light emitting structure that is divided into segments. The light emitting structure includes a first layer of semiconductor material of a first conductivity type deposited on the substrate, an active layer overlying the first layer, and a second layer of semiconductor material of an opposite conductivity type from the first conductivity type overlying the active layer. A barrier divides the light emitting structure into first and second segments that are electrically isolated from one another. A serial connection electrode connects the first layer in the first segment to the second layer in the second segment. A power contact is electrically connected to the second layer in the first segment, and a second power contact electrically connected to the first layer in the second segment.Type: ApplicationFiled: July 30, 2015Publication date: November 26, 2015Inventors: Steven D. Lester, Chih-Wei Chuang
-
Patent number: 9123853Abstract: A light source and method for making the same are disclosed. The light source includes a conducting substrate, and a light emitting structure that is divided into segments. The light emitting structure includes a first layer of semiconductor material of a first conductivity type deposited on the substrate, an active layer overlying the first layer, and a second layer of semiconductor material of an opposite conductivity type from the first conductivity type overlying the active layer. A barrier divides the light emitting structure into first and second segments that are electrically isolated from one another. A serial connection electrode connects the first layer in the first segment to the second layer in the second segment. A power contact is electrically connected to the second layer in the first segment, and a second power contact electrically connected to the first layer in the second segment.Type: GrantFiled: August 5, 2013Date of Patent: September 1, 2015Assignee: Manutius IP, Inc.Inventors: Steven D. Lester, Chih-Wei Chuang
-
Publication number: 20150228860Abstract: Aspects include Light Emitting Diodes that have a GaN-based light emitting region and a metallic electrode. The metallic electrode can be physically separated from the GaN-based light emitted region by a layer of porous dielectric, which provides a reflecting region between at least a portion of the metallic electrode and the GaN-based light emitting region.Type: ApplicationFiled: April 22, 2015Publication date: August 13, 2015Inventors: Frank T. SHUM, William W. SO, Steven D. LESTER
-
Patent number: 9105815Abstract: Aspects include Light Emitting Diodes that have a GaN-based light emitting region and a metallic electrode. The metallic electrode can be physically separated from the GaN-based light emitted region by a layer of porous dielectric, which provides a reflecting region between at least a portion of the metallic electrode and the GaN-based light emitting region.Type: GrantFiled: November 11, 2012Date of Patent: August 11, 2015Assignee: BRIDGELUX, INC.Inventors: Frank T. Shum, William W. So, Steven D. Lester
-
Patent number: 9099613Abstract: Aspects include Light Emitting Diodes that have a GaN-based light emitting region and a metallic electrode. The metallic electrode can be physically separated from the GaN-based light emitted region by a layer of porous dielectric, which provides a reflecting region between at least a portion of the metallic electrode and the GaN-based light emitting region.Type: GrantFiled: August 11, 2014Date of Patent: August 4, 2015Assignee: BRIDGELUX, INC.Inventors: Frank T. Shum, William W. So, Steven D. Lester
-
Patent number: 9082892Abstract: A device having a carrier, a light-emitting structure, and first and second electrodes is disclosed. The light-emitting structure includes an active layer sandwiched between a p-type GaN layer and an n-type GaN layer, the active layer emitting light of a predetermined wavelength in the active layer when electrons and holes from the n-type GaN layer and the p-type GaN layer, respectively, combine therein. The first and second electrodes are bonded to the surfaces of the p-type and n-type GaN layers that are not adjacent to the active layer. The n-type GaN layer has a thickness less than 1.25 ?m. The carrier is bonded to the light emitting structure during the thinning of the n-type GaN layer. The thinned light-emitting structure can be transferred to a second carrier to provide a device that is analogous to conventional LEDs having contacts on the top surface of the LED.Type: GrantFiled: January 30, 2013Date of Patent: July 14, 2015Assignee: Manulius IP, Inc.Inventors: Steven D. Lester, Frank T. Shum
-
Publication number: 20150125974Abstract: A device having a carrier, a light-emitting structure, and first and second electrodes is disclosed. The light-emitting structure includes an active layer sandwiched between a p-type GaN layer and an n-type GaN layer, the active layer emitting light of a predetermined wavelength in the active layer when electrons and holes from the n-type GaN layer and the p-type GaN layer, respectively, combine therein. The first and second electrodes are bonded to the surfaces of the p-type and n-type GaN layers that are not adjacent to the active layer. The n-type GaN layer has a thickness less than 1.25 ?m. The carrier is bonded to the light emitting structure during the thinning of the n-type GaN layer. The thinned light-emitting structure can be transferred to a second carrier to provide a device that is analogous to conventional LEDs having contacts on the top surface of the LED.Type: ApplicationFiled: January 30, 2013Publication date: May 7, 2015Applicant: MANUTIUS IP, INC.Inventors: Steven D. Lester, Frank T. Shum
-
Publication number: 20140346554Abstract: Aspects include Light Emitting Diodes that have a GaN-based light emitting region and a metallic electrode. The metallic electrode can be physically separated from the GaN-based light emitted region by a layer of porous dielectric, which provides a reflecting region between at least a portion of the metallic electrode and the GaN-based light emitting region.Type: ApplicationFiled: August 11, 2014Publication date: November 27, 2014Inventors: Frank T. Shum, William W. So, Steven D. Lester
-
Publication number: 20140213000Abstract: A device having a carrier, a light-emitting structure, and first and second electrodes is disclosed. The light-emitting structure includes an active layer sandwiched between a p-type GaN layer and an n-type GaN layer, the active layer emitting light of a predetermined wavelength in the active layer when electrons and holes from the n-type GaN layer and the p-type GaN layer, respectively, combine therein. The first and second electrodes are bonded to the surfaces of the p-type and n-type GaN layers that are not adjacent to the active layer. The n-type GaN layer has a thickness less than 1.25 ?m. The carrier is bonded to the light emitting structure during the thinning of the n-type GaN layer. The thinned light-emitting structure can be transferred to a second carrier to provide a device that is analogous to conventional LEDs having contacts on the top surface of the LED.Type: ApplicationFiled: January 30, 2013Publication date: July 31, 2014Applicant: TOSHIBA TECHNO CENTER INC.Inventors: Steven D. Lester, Frank T. Shum
-
Patent number: 8729580Abstract: A light emitting device based on a AlInGaN materials system wherein a coating is used to improve the extraction of light from a device. A coating has a very low optical loss and an index of refraction greater than 2. In a preferred embodiment the coating is made from Ta2O5, Nb2O5, TiO2, or SiC and has a thickness between about 0.01 and 10 microns. A surface of a coating material may be textured or shaped to increase its surface area and improve light extraction. A surface of the coating material can also be shaped to engineer the directionality of light escaping the layer. A coating can be applied directly to a surface or multiple surfaces of a light emitting device or can be applied onto a contact material. A coating may also serve as a passivation or protection layer for a device.Type: GrantFiled: December 6, 2005Date of Patent: May 20, 2014Assignee: Toshiba Techno Center, Inc.Inventor: Steven D. Lester
-
Publication number: 20140124806Abstract: An AlInGaN light emitting device having a coating is used to improve the extraction of light from a device. A coating has a very low optical loss and an index of refraction greater than 2, preferably having an index of refraction close to or greater than the index of refraction of GaN. The coating can be made from Ta2O5, Nb2O5, TiO2, or SiC and has can have a thickness between 0.01 and 10 microns. A surface of the coating material may be textured or shaped to increase its surface area and improve light extraction. A coating can be applied directly to one or multiple surfaces of the light emitting device or can be applied onto a contact material and can serve as a passivation or as a protection layer for a device.Type: ApplicationFiled: October 27, 2009Publication date: May 8, 2014Applicant: BRIDGELUX, INC.Inventor: Steven D. Lester
-
Publication number: 20140117404Abstract: A light-emitting device includes first and second semiconductor layers and a light-emitting layer between the first and second semiconductor layers. The light-emitting device also includes an improved electrode structures.Type: ApplicationFiled: January 8, 2014Publication date: May 1, 2014Applicant: TOSHIBA TECHNO CENTER INC.Inventors: Steven D. LESTER, Chao-Kun LIN
-
Publication number: 20140054638Abstract: Light emitting devices comprise a light emitting component, such as a GaN LED having active material layers supported by a Silicon substrate, which can be a growth substrate, or attached. Phosphor(s) can be disposed relative to the light emitting component to absorb a primary emission, and produce a secondary emission that can be relatively tuned or selected so that their combination produces light of a desired spectrum, such as light appearing white. The Silicon substrate has exposed sidewalls, which can be angled, with respect to planar surfaces of the substrate, and a light reflecting material, such as a diffusely reflective material coats the sidewalls. The reflective material can be opaque to the primary and secondary emissions. If other exposed portions of the Silicon substrate exist and are exposed to primary or secondary light, these other exposed portions can be coated with such light reflecting material.Type: ApplicationFiled: March 11, 2013Publication date: February 27, 2014Applicant: TOSHIBA TECHNO CENTER, INC.Inventors: Steven D. Lester, Long Yang, Chao-Kun Lin
-
Patent number: 8637891Abstract: A light-emitting device includes first and second semiconductor layers and a light-emitting layer between the first and second semiconductor layers. The light-emitting device also includes an improved electrode structures.Type: GrantFiled: May 27, 2009Date of Patent: January 28, 2014Assignee: Toshiba Techno Center Inc.Inventors: Steven D. Lester, Chao-Kun Lin
-
Publication number: 20130313519Abstract: A light source and method for making the same are disclosed. The light source includes a conducting substrate, and a light emitting structure that is divided into segments. The light emitting structure includes a first layer of semiconductor material of a first conductivity type deposited on the substrate, an active layer overlying the first layer, and a second layer of semiconductor material of an opposite conductivity type from the first conductivity type overlying the active layer. A barrier divides the light emitting structure into first and second segments that are electrically isolated from one another. A serial connection electrode connects the first layer in the first segment to the second layer in the second segment. A power contact is electrically connected to the second layer in the first segment, and a second power contact electrically connected to the first layer in the second segment.Type: ApplicationFiled: August 5, 2013Publication date: November 28, 2013Applicant: TOSHIBA TECHNO CENTER INC.Inventors: Steven D. Lester, CHIH-WEI CHUANG
-
Patent number: 8581267Abstract: A light source and method for making the same are disclosed. The light source includes a conducting substrate, and a light emitting structure that is divided into segments. The light emitting structure includes a first layer of semiconductor material of a first conductivity type deposited on the substrate, an active layer overlying the first layer, and a second layer of semiconductor material of an opposite conductivity type from the first conductivity type overlying the active layer. A barrier divides the light emitting structure into first and second segments that are electrically isolated from one another. A serial connection electrode connects the first layer in the first segment to the second layer in the second segment. A power contact is electrically connected to the second layer in the first segment, and a second power contact electrically connected to the first layer in the second segment.Type: GrantFiled: November 9, 2011Date of Patent: November 12, 2013Assignee: Toshiba Techno Center Inc.Inventors: Steven D. Lester, Chih-Wei Chuang
-
Patent number: 8552465Abstract: A device and method for making the same are disclosed. The device includes a substrate having a first TEC, a stress relief layer overlying the substrate, and crystalline cap layer. The crystalline cap layer overlies the stress relief layer. The cap layer has a second TEC different from the first TEC. The stress relief layer includes an amorphous material that relieves stress between the crystalline substrate and the cap layer arising from differences in the first and second TECs at a growth temperature at which layers are grown epitaxially on the cap layer. The device can be used to construct various semiconductor devices including GaN LEDs that are fabricated on silicon or SiC wafers. The stress relief layer is generated by converting a layer of precursor material on the substrate after the cap layer has been grown to a stress-relief layer.Type: GrantFiled: November 9, 2011Date of Patent: October 8, 2013Assignee: Toshiba Techno Center Inc.Inventor: Steven D. Lester