Epistar Corporation

Industrial Technology Research Institute

Ming-Jiunn Jou

Min-Hsun Hsieh

Biing-Jye Lee

Chia-Cheng Liu

Chih-Chiang Lu

Chao-Nien Huang

Shu-Wen Sung

Shane-Shyan Wey

Chuan-Ming Chang

Kuen-Ru Chuang

Jacob C Tarn

Keun-Ru Chuang

Tzer-Perng Chen

Wen-Huang Liu

Jyh-Feng Lin

Chin-Yuan Chen

Chiung-Sheng Shyu

Jyi-Ren Deng

Jenn-Yu Kao

Ming-Yung Jow

Jinn-Kung Sheu

A light emitting diode having a transparent substrate and a method for manufacturing the same. The light emitting diode is formed by creating two semiconductor multilayers and bonding them. The first semiconductor multilayer is formed on a non-transparent substrate. The second semiconductor multilayer is created by forming an amorphous interface layer on a transparent substrate. The two semiconductor multilayers are bonded and the non-transparent substrate is removed, leaving a semiconductor multilayer with a transparent substrate.

Method of making a multilayer structure

Light emitting diode having a transparent substrate

A nitride light-emitting device having an adhesive reflecting layer includes a transparent adhesive layer, a nitride light-emitting stack layer and a metal reflecting layer. The transparent adhesive layer adheres the nitride light-emitting stack layer and the metal reflecting layer. Therefore, the metal reflecting layer can reflect light emitted from the light-emitting stack layer to increase the brightness of the nitride light-emitting device.

Nitride light-emitting device having an adhesive reflecting layer

Method for manufacturing a light emitting diode having a transparent substrate

A high brightness light emitting diode having a distributed contact area comprising a first electrode; a semiconductor substrate formed on the first electrode; a first cladding layer of a first conductivity type formed on the semiconductor substrate; an active layer formed on the first cladding layer; a second cladding layer of a second conductivity type formed on the active layer; a window layer of a second conductivity type formed on the second cladding layer; a distributed contact area in a predetermined pattern formed on the window layer; a transparent conductive layer formed over the distributed contact area and the window layer, the transparent conductive layer being in ohmic contact with the distributed contact area and a Shottky barrier being formed between the transparent conductive layer and the window layer; and a second electrode formed on the transparent conductive layer.

High brightness light emitting diode having a layer of distributed contacts

A high-brightness light emitting diode is provided. It comprises a first electrode; a semiconductor substrate formed on the first electrode; a first cladding layer of a first conductivity type formed on the semiconductor substrate; an active layer formed on the first cladding layer; a second cladding layer of a second conductivity type formed on the active layer; a window layer of the second conductivity type formed on the second cladding layer and having an upper surface and a bottom surface, wherein a groove of a predetermined shape is formed at a predetermined location and substantially extends from the upper surface to the bottom surface so that the window layer is substantially separated into a first window portion and a second window portion and the current in the first window portion substantially cannot flow into the second window portion; a contact layer formed on the first window portion; a transparent conductive layer consisting of a first conductive portion and a second conductive portion, wherein the first conductive portion is formed on the contact layer and an ohmic contact is formed between the first conductive portion and the contact layer, the second conductive portion contacts with the surface of the groove and the upper surface of the second window portion, and a Schottky barrier is formed between the conductive portion and the window layer; and a second electrode formed on the conductive layer at a location over the second window portion.

High-brightness light emitting diode

A structure of a light emitting diode (LED) having high brightness is disclosed. This LED includes a substrate on a first electrode, a first cladding layer of a first conductivity type on the substrate, an active layer on the first cladding layer, a second cladding layer of a second conductivity type on the active layer, a window layer of the second conductivity type on the second cladding layer, wherein the electrical resistivity of the window layer is less than that of the second cladding layer, a contact layer of the second conductivity type on the window layer for providing ohmic contact, and a conductive transparent oxide layer on the contact layer, wherein the electrical resistivity of the conductive transparent oxide layer is less than that of the window layer and the contact layer.

High efficiency light emitting diode with distributed Bragg reflector

A surface-emitting AlGaInP LED is disclosed. The LED uses a GaP layer as a window layer to eliminate the current crowding effect, or may has an ITO window layer and use GaP, instead of GaAs, as the substrate to eliminate the current-crowding effect and avoid the emitted light being absorbed by the substrate. The GaP layer is bonded to the double hetero-structure epitaxy layer by a wafer bonding technique. The present invention, however, provides a manufacturing procedure which is easier and more reliable to handle than prior arts.

Light-emitting diodes with high illumination

A structure of a light emitting diode (LED) having high brightness is disclosed. This LED includes a substrate formed on a first electrode, a first cladding layer of a first conductivity type formed on the substrate, an active layer formed on the first cladding layer, a second cladding layer of a second conductivity type formed on the active layer, a window layer of the second conductivity type formed on the second cladding layer, wherein the electrical resistivity of the window layer is less than the electrical resistivity of the second cladding layer, a contact layer of the second conductivity type formed on the window layer for providing ohmic contact, a conductive transparent oxide layer formed on the contact layer, and a current blocking region formed in the LED. The current blocking region is approximately aligned with a second electrode, and can be the contact layer having a hollow portion therein, an insulating region formed on the contact layer, an ion implanted region in the contact layer and the window layer, or a diffused region in the contact layer and the window layer.

Light emitting diode having transparent conductive oxide formed on the

A surface-emitting AlGaInP LED is disclosed. The manufacturing method comprises the steps of: (i) forming a buffer layer, a first type of AlGaInP cladding layer, a AlGaInP active layer, a second type of AlGaInP cladding layer, and a second type of contact layer on a first type of GaAs substrate; (ii) forming a conductive transparent electrode; (iii) by using photolithography and etching techniques, a first photoresist layer with a hole is formed on the middle above the transparent electrode; (iv) etching the portion of the transparent electrode and the second type of GaAs layer not covered by the photoresist layer until the second type of AlGaInP cladding layer; (v) forming a metal layer on the hole being etched to form a Schottky barrier; (vi) thermal annealed to thicken an native oxide formed between the metal layer and the second type of AlGaInP cladding layer to increase the Schottky barrier level; (vii) removing the first photoresist layer, and coating a back electrode on an opposite surface of the first type of GaAs substrate; (viii) employing the photolithography and etching techniques and a mask being used in the photolithography of step (iii) to form a second photoresist layer with a hole at the center thereof; and (ix) forming a second metal over the metal layer being formed on the second type of AlGaInP cladding layer at step (v). The Schottky barrier and the native oxide serve as a current-blocking layer, and the luminance of a light-emitting diode is improved.

Light-emitting diodes and method of manufacturing the same

A surface emitting AlGaInP LED having an ITO layer as a window layer to eliminate the current crowding effect, and an ohmic contact layer between its double hetero-structure of AlGaInP and the ITO layer, so that ITO can be utilized with the double hetero-structure of AlGaInP.

Surface light emitting diode with electrically conductive window layer

A light emitting diode is provided with a window layer of ZnSSe semiconductor material having a second conductivity type. The second conductivity type ZnSSe window layer has a low electrical resistivity so that it can be used as a current spreading layer, and a bandgap higher than that of the active layer so that it is transparent to light emitted from the active layers. The second conductivity type ZnSSe window layer can be doped with a donor concentration of more than 10.sup.18 cm.sup.-3. Furthermore, its lattice constant is close to that of the active layers and confining layers so that deterioration in optical characteristic due to lattice mismatch is minimized.

Growing community of inventors

Hsin-Chu, Taiwan

Ming-Jiunn Jou