Rohm Co., Ltd.

Rohm Gmbh

Rohn Co., Ltd.

Tsuyoshi Tsutsui

Masayuki Sonobe

Shunji Nakata

Norikazu Itoh

Yukio Shakuda

Atsushi Yamaguchi

Norikazu Ito

Ken Nakahara

Shinji Isokawa

Mitsuhiko Sakai

Hidekazu Toda

Kotaro Ogura

Koutarou Ogura

Yasuo Miyano

Munekazu Tsujikawa

There are provided a nitride semiconductor light emitting device having a structure enabling enhanced external quantum efficiency by effectively taking out light which is apt to repeat total reflection within a semiconductor lamination portion and a substrate and attenuate, and a method for manufacturing the same. A semiconductor lamination portion () including a first conductivity type layer and a second conductivity type layer, made of nitride semiconductor, is provided on a surface of the substrate () made of, for example, sapphire or the like. A first electrode (for example, p-side electrode ()) is provided electrically connected to the first conductivity type layer (for example, p-type layer ()) on a surface side of the semiconductor lamination portion (), and a second electrode (for example, n-side electrode ()) is provided electrically connected to the second conductivity type layer (for example, n-type layer ()). A part of the semiconductor lamination portion () is removed at a surrounding region of a chip of the semiconductor lamination portion () by etching so that column portions () stand side by side by leaving the semiconductor lamination portion without etching, and the n-type layer () expose around the column portions ().

Semiconductor light emitting device and method for manufacturing the same

A semiconductor light-emitting elementis mounted on a substratewith an anisotropically conductive adhesive, which has electrically conductive particlesdispersion-mixed with a thermosetting resin, laid between a pair of electrodesand' formed on the same surface of the semiconductor light-emitting element and wiring electrodesand&#x2032; formed on the substrate. Depressionsand&#x2032; are formed in the portion of the surface of the wiring electrodesand&#x2032; facing the semiconductor light-emitting elementso that the electrically conductive particlesare stably present between the pair of electrodesand&#x2032; and the wiring electrodesand

Semiconductor light-emitting device having a semiconductor light-emitting element mounted on a substrate with anisotropically conductive adhesive interposed therebetween

A semiconductor lamination including an n-type layer and a p-type layer composed of a gallium nitride based compound semiconductor and forming a light emitting region is formed on the surface of a substrate. A p-side electrode is formed through a diffusion metal layer on the surface of the semiconductor lamination. Also, an n-side electrode is formed on the n-type layer exposed by etching off a part of the semiconductor lamination. The n-side electrode is formed of an ohmic contact electrode and a bonding electrode. The bonding electrode is formed in such a manner as to cover the surface and the sides of the ohmic contact electrode. As a result, a semiconductor light emitting device made of a gallium nitride based compound semiconductor is produced having an electrode structure of a superior ohmic contact characteristic and a superior wire bonding characteristic.

Semiconductor light emitting device and method of manufacturing the same

Semiconductor light-emitting elements are produced by providing a wafer substrate of GaP, epitaxially growing on this substrate a semiconductor layered structure including an n-type layer and a p-type layer of GaP for providing a light-emitting layer, forming top electrodes on the semiconductor layered structure each over a portion of the area corresponding to one of the chips into which the substrate is to be later divided, forming a bottom electrode on the bottom surface of the substrate, dicing the wafer substrate into the individual chips, and thereafter carrying out a surface-roughening process on externally exposed portions of the semiconductor structure by means of hydrochloric acid. Each of the top electrodes is of a three-layer structure with a contact metal layer which may be of an alloy of Au and makes an ohmic contact with the GaP of the semiconductor layered structure, a Mo layer on the contact metal layer and an Au layer on the Mo layer.

Method of producing semiconductor light-emitting element

A mask,for vapor deposition is made of glass. Through-holes,are formed in the glass mask,so that they make a prescribed pattern on the surface of a semiconductor substrate,The peripheral wall of the through-hole is tapered so that the opening face,from which evaporated atoms are introduced is larger than the opening face,facing the deposition surface of the semiconductor substrate. The evaporated metal atoms having flied aslant toward the opening face,from which the evaporated atoms are introduced can pass through the through-hole,so that the evaporated metal atoms are deposited on the deposition surface of the semiconductor substrate. A desired thin film pattern inclusive of an electrode pattern can be easily formed on the surface of a semiconductor substrate, thereby improving the production yield of a semiconductor device.

Method of manufacturing semiconductor device and mask for forming thin film pattern

A semiconductor light emitting device includes a substrate, an n-type layer formed of gallium-nitride based compound semiconductor formed on the substrate, and a p-type layer formed of gallium-nitride based compound semiconductor formed on the substrate. Semiconductor overlying layers are constituted by the n-type layer and the p-type layer on the substrate. A light emitting layer is formed together with the n-type and p-type layers in the semiconductor overlying layers to emit light. At least one of the n-type layer and the p-type layer is formed by three or more overlying sublayers including a sublayer of Al,Ga,N (0<y&lE;0.5) and a sublayer of Al,Ga,N (0&lE;u<y). With this structure, the semiconductor light emitting device is almost free from lattice mismatch to thereby enhance electron mobility and hence light emission efficiency even where the overlying semiconductor layers are different in lattice constant from the substrate.

Fabrication of semiconductor light emitting device

In a method for manufacturing semiconductor light emitting device, when a gallium nitride based compound semiconductor layers which include at least an n-type layer and p-type layer and which form a light emitting layer, are laminated on a substrate and heat treatment is performed for activation of the p-type layer of the laminated semiconductor layers, the heat treatment is performed under an atmosphere including oxygen. With this arrangement, the heat treatment for activating the p-type layer of the laminated semiconductor layers comprising gallium nitride based compound semiconductor can be performed in a short time and moreover to reliably perform activation.

Method for manufacturing semiconductor light emitting device

Semiconductor layers forming a light emitting layer and including an n-type layer and p-type layer are formed onto a substrate, then the n-type layer is exposed by removing a part of the laminated semiconductor layers. p-side electrode and n-side electrode are then respectively formed on the p-type layer on the surface of the laminated semiconductor layers and the exposed n-type layer, respectively in an electrically connected manner, followed by dicing of the substrate from the exposed n-type layer to the substrate at portions at which breaking of the substrate is performed. Then a protection film is provided on the entire surface of the laminated semiconductor layers as to expose the p-side and n-side electrodes, and breaking of the substrate is performed at dicing portions into individual chips. Consequently, semiconductor light emitting devices can be obtained by breaking the wafer into individual chips without etching the protection film and without damaging the protection film at the time of breaking. Also, the light emitting devices can be improved.

A semiconductor layered portion is formed of a gallium-nitride semiconductor overlying a substrate and having an n-type layer and a p-type layer to form a light emitting layer having a pn junction or a doublehetero junction. A gradient layer is provided at an interfacial portion between an lower layer and an upper layer of the semiconductor layered portion, wherein the gradient layer has a composition varied from a composition from said lower layer to a composition of the upper layer. With this structure, a semiconductor light emitting device which is excellent in light emitting efficiency is provided by reducing crystal lattice mismatch between semiconductor layers formed different in lattice constant on a substrate.

An n-type layer (,) and a p-type layer (,) which are made of a gallium nitride based compound semiconductor are provided on a substrate (,) so that a light emitting layer forming portion (,) for forming a light emitting layer is provided. A gallium nitride based compound semiconductor layer containing oxygen is used for at least one layer of the light emitting layer forming portion (,). In the case where a buffer layer (,) made of the gallium nitride based compound semiconductor or aluminum nitride is provided between the substrate (,) and the light emitting layer forming portion (,), the buffer layer (,) and/or at least one layer of the light emitting layer forming portion (,) may contain oxygen. By such a structure, crystal defects of the semiconductor layer of the light emitting layer forming portion (,) can be decreased and a luminance can highly be enhanced. Thus, it is possible to obtain a blue color type semiconductor light emitting device having a high luminance.

Disclosed is a method of manufacturing a semiconductor light emitting device. Semiconductor overlying layers are formed on a substrate in a state of a wafer so that a light emitting area is provided therein. The semiconductor overlying layers includes first and second conductivity type layers. Part of the semiconductor overlying layers including the first conductivity type layer on a surface thereof is removed so as to expose part of the second conductivity type layer. Electrodes are formed, for each chip, respectively in connection with the surface of the first conductivity type layer and the surface of the exposed second conductivity type layer. The wafer is divided into individual chips. The exposed areas of the second conductivity type semiconductor layer is provided only part of a peripheral area of the chip so that the first conductivity type semiconductor layer is directly separated during dividing the wafer into individual chips. With such a method, when dividing a wafer into chips, the inefficiency of the space (etched areas do not contribute to light emission) is eliminated in etch-removing the semiconductor overlying layers at areas to be divided, thereby improving chip yield and hence reducing cost.

Method of manufacturing a semiconductor light emitting device

Deposited on a wafer-like substrate for forming a plurality of light emitting device chips is a semiconductor layer laminate with a different property from that of the substrate. Then, electrodes are provided on and in electric connection with a top semiconductor layer of a first conductivity type of the semiconductor layer laminate, and on and in electric connection with a semiconductor layer of a second conductivity type, exposed by locally etching the semiconductor layer laminate, in association with the individual chips. Then, the semiconductor layer laminate is etched at boundary portions between the chips to expose the substrate, and the substrate is broken at the exposed portions into the chips. As the semiconductor layer laminate is etched out at the boundary portions between the chips before breaking the wafer, breaking can be facilitated without damaging the light emitting portions of the semiconductor layer laminate. This helps provide high-performance semiconductor light emitting devices.

A semiconductor light emitting device has semiconductor layers including a first conductivity type semiconductor layer and a second conductivity type semiconductor layer formed on a substrate. A first electrode is formed in electrical connection with the first conductivity type semiconductor layer on a surface side of the semiconductor layers. The second conductivity type semiconductor layer is exposed by partly etch-removing an end portion of the semiconductor layers. A second electrode is provided in electrical connection with the exposed second conductivity type layer. The first and second electrodes are formed such that the electrodes are in parallel, in plan form, with each other at opposite portions thereof. As a result, the current path is constant in electric resistance, providing a semiconductor light emitting device that is constant in brightness, long in service life and high in brightness.

Semiconductor light emitting device

There is provided a semiconductor laminated portion in which gallium nitride based compound semiconductor layers including an n-type layer and a p-type layer are laminated for forming an emitting layer on a substrate. Then, an n-side electrode and a p-side electrode are provided so as to be electrically connected to the n-type layer and p-type layer of the semiconductor laminated portion, respectively. The n-type layer includes at least an n-type first layer and an n.sup.+ -type second layer so that the carrier concentration of the portion to be provided with the n-side electrode is higher than the carrier concentration of the portion in contact with the emitting layer. Consequently, the ohmic contact characteristics of the n-type layer and n-side electrode are improved to reduce a forward voltage, resulting in a semiconductor light emitting device with high light emitting efficiency.

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Kyoto, Japan

Tsuyoshi Tsutsui