Patents by Inventor Shu-Woei Chiou

Shu-Woei Chiou 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: 6552369
    Abstract: A light emitting diode (LED) is disclosed. An emitted light can be prevented from being absorbed by a substrate using a Bragg reflector layer with high reflectivity. The present invention provides a Bragg reflector layer comprising a plurality of high aluminum-containing AlGaAs/AlGaInP layers or high aluminum-containing AlGaAs/ low aluminum-containing AlGaInP layers formed on the substrate before the epitaxial structure of the light emitting diode being formed. Since the high aluminum-containing AlGaAs is oxidized and formed an oxide of a lower refraction index, the reflectivity and high reflection zones of the oxidized Bragg reflector layer are much larger. According to the electrical insulation characteristic of the oxide, the Bragg reflector layer can limit the current within the oxidized regions of high aluminum-containing AbGaAs layer. Therefore, the aforementioned light emitting diode structure has a higher brightness than the conventional light emitting diode.
    Type: Grant
    Filed: October 31, 2001
    Date of Patent: April 22, 2003
    Assignee: United Epitaxy Company LTD
    Inventors: Shu-Woei Chiou, Holin Chang, Tzer-Perng Chen, Chih-Sung Chang
  • Publication number: 20020145147
    Abstract: A light emitting diode (LED) is disclosed. The problem of an emitting light absorbed by a substrate can be prevented by using a bragg reflector layer with high reflectivity. The present invention provides a high reflectivity bragg reflector layer to reflect the light generated from LED, which comprises high aluminum-contained AlGaAs/AlGaInP layers or high aluminum-contained AlGaAs/low aluminum-contained AlGaInP layers, formed on the substrate before the vertically stacked epitaxial structure of the light emitting diode is formed. Due to the higher oxidation ability of the high aluminum-contained AlGaAs layers and the lower refraction index of the oxide thereof, the wavelength reflected by the bragg reflector layer can cover a wider spectrum and the reflectivity thereof is very high. Since the oxidized AlGaAs layer is an electrical insulator, the present invention provides electrodes located on the same side of the light emitting diode.
    Type: Application
    Filed: December 18, 2001
    Publication date: October 10, 2002
    Inventors: Shu-Woei Chiou, Holin Chang, Tzer-Perng Chen, Chih-Sung Chang
  • Patent number: 6458612
    Abstract: A method for fabricating high efficiency light-emitting diode (LED) adhered to a transparent substrate is disclosed. To begin with, forming a semiconductor substrate, is followed by sequentially forming an etching stopper, a first type ohmic contact layer, a double heterostructure and a second ohmic contact layer. Afterwards, the transparent substrate, such as preferably glass, is adhered onto the second ohmic contact layer and then the GaAs substrate is removed away. After that, the first type cladding layer and the undoped active layer is etched in turn by using the second type ohmic contact layer as the etching stopper. Finally, a first electrode is formed on the first type ohmic contact layer and a second electrode is formed on the second type ohmic contact layer, respectively. The present invention utilizes some features, such as high transmittance and lower absorptivity, of the glass adhered to the second ohmic contact layer to visible light for increasing luminous intensity of the LED.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: October 1, 2002
    Assignee: United Epitaxy Company, Inc.
    Inventors: Tzer-Perng Chen, Chih-Sung Chang, Shu-Woei Chiou
  • Publication number: 20020055218
    Abstract: A light emitting diode (LED) is disclosed. An emitted light can be prevented from being absorbed by a substrate by using a bragg reflector layer with high reflectivity. The present invention provides a bragg reflector layer comprising a plurality of high aluminum-contained AlGaAs/AlGaInP layers or high aluminumcontained AlGaAs/low aluminum-contained AlGaInP layers formed on the substrate before the epitaxial structure of the light emitting diode being formed. Since the high aluminum-contained AlGaAs is oxidized and formed an oxide of a lower refraction index, the reflectivity and high reflection zones of the oxidized bragg reflector layer are much larger. According to the electrical insulation characteristic of the oxide, the bragg reflector layer can limit the current within the oxidized regions of high aluminum-contained AlGaAs layer. Therefore, the aforementioned light emitting diode structure has a higher brightness than the conventional light emitting diode.
    Type: Application
    Filed: October 31, 2001
    Publication date: May 9, 2002
    Inventors: Shu-Woei Chiou, Holin Chang, Tzer-Perng Chen, Chih-Sung Chang
  • Publication number: 20020034835
    Abstract: A method for fabricating high efficiency light-emitting diode (LED) adhered to a transparent substrate is disclosed. To begin with, forming a semiconductor substrate, is followed by sequentially forming an etching stopper, a first type ohmic contact layer, a double heterostructure and a second ohmic contact layer. Afterwards, the transparent substrate, such as preferably glass, is adhered onto the second ohmic contact layer and then the GaAs substrate is removed away. After that, the first type cladding layer and the undoped active layer is etched in turn by using the second type ohmic contact layer as the etching stopper. Finally, a first electrode is formed on the first type ohmic contact layer and a second electrode is formed on the second type ohmic contact layer, respectively. The present invention utilizes some features, such as high transmittance and lower absorptivity, of the glass adhered to the second ohmic contact layer to visible light for increasing luminous intensity of the LED.
    Type: Application
    Filed: September 19, 2001
    Publication date: March 21, 2002
    Applicant: UNITED EPITAXY COMPANY, INC.
    Inventors: Tzer-Perng Chen, Chih-Sung Chang, Shu-Woei Chiou