Abstract: A gallium nitride-based semiconductor light-emitting device includes a sapphire substrate having a nitridated upper surface; a polarity conversion layer formed on the sapphire substrate and made of MgN-based single ciystals; a first conductive gallium nitride-based semiconductor layer formed on the polarity conversion layer; an active layer formed on the first conductive gallium nitride-based semiconductor layer; and a second conductive gallium nitride-based semiconductor layer formed on the active layer.

Abstract: The present invention provides a nitride based semiconductor device comprising an active layer having a quantum well layer and a quantum barrier layer, wherein the device includes an electron emitting layer formed of at least two repeats of a first nitride semiconductor layer and a second nitride semiconductor layer having different compositions between a n-type nitride semiconductor layer and the active layer, the first nitride semiconductor layer has an energy band gap greater than that of the quantum well layer, smaller than that of the quantum barrier layer, and decreasing closer to the active layer, and the second nitride semiconductor layer has an energy band gap at least higher than that of the adjacent first nitride semiconductor layer(s) and has a thickness capable of tunneling electrons.

Abstract: Disclosed is a method of fabricating nitride semiconductors in a MOCVD reactor. GaN is first deposited on an inner wall of the MOCVD reactor, and a sapphire substrate is loaded into the MOCVD reactor. The sapphire substrate is heated and etching gas is injected into the MOCVD reactor. NH3 gas is injected into the MOCVD reactor to nitrify the surface of the sapphire substrate. A nitride semiconductor layer is grown on the nitrified sapphire substrate. By surface-reforming the sapphire substrate and then growing the nitride semiconductor layer on the surface-reformed sapphire substrate via MOCVD without formation of a low temperature buffer layer, an excellent nitride semiconductor structure can be realized. In this circumstance, the nitride semiconductor layer for example of GaN can be grown effectively on the surface-treated sapphire substrate because GaN deposition occurs on the sapphire substrate while it is etched.

Abstract: Disclosed is a method of fabricating nitride semiconductors in a MOCVD reactor. GaN is first deposited on an inner wall of the MOCVD reactor, and a sapphire substrate is loaded into the MOCVD reactor. The sapphire substrate is heated and etching gas is injected into the MOCVD reactor. NH3 gas is injected into the MOCVD reactor to nitrify the surface of the sapphire substrate. A nitride semiconductor layer is grown on the nitrified sapphire substrate. By surface-reforming the sapphire substrate and then growing the nitride semiconductor layer on the surface-reformed sapphire substrate via MOCVD without formation of a low temperature buffer layer, an excellent nitride semiconductor structure can be realized. In this circumstance, the nitride semiconductor layer for example of GaN can be grown effectively on the surface-treated sapphire substrate because GaN deposition occurs on the sapphire substrate while it is etched.

Abstract: To fabricate a magnetic field sensor, a copper barrier film is formed. A magnetic metal film is formed on the barrier film. A plurality of trenches is formed with a desired thickness in the magnetic metal film. A copper film is formed in the plurality of trenches, so that multiple layers of magnetic metal film and copper film are formed. The RF semiconductor device equipped with the magnetic field sensor includes a magnetic field sensor made by the above method. The magnetic field sensor is attached on a semiconductor substrate. Metal wirings are formed at near the both sides of the magnetic field sensor. An insulating film is formed on top. An inductor is formed on the insulating film at predetermined locations.

Abstract: Disclosed is a method for manufacturing a semiconductor laser device, comprising the steps of: (a) forming a first conductive-type clad layer, an active layer, and a second conductive-type clad layer on a first conductive-type semiconductor substrate; (b) forming a ridge structure by selectively etching the second conductive-type clad layer; (c) forming a current blocking layer around the ridge structure, the current blocking layer having protrusions on the upper surface thereof adjacent to the ridge structure, and an amorphous and/or polycrystalline layer on a partial area thereof; and (d) removing at least the amorphous and/or polycrystalline layer from the current blocking layer, and wet-etching the upper surface of the current blocking layer so that the protrusions are reduced in size;

Abstract: Disclosed is a method of forming the metal line in the semiconductor device. The method comprising the steps of forming an interlay insulating film on a semiconductor substrate in which a lower line is formed, patterning the interlay insulating film to form an aperture unit for forming an upper line connected to the lower line, cooling the semiconductor substrate in which the aperture unit is formed at a given temperature, implementing a cleaning process using a hydrogen reduction reaction in order to remove polymer formed on the sidewall of the aperture unit and a metal oxide film formed on the lower line, implementing an annealing process in-situ within a chamber in which the cleaning process is implemented, and burying the aperture unit with a conductive material to form an upper line.

Abstract: Disclosed is a method of forming the metal line in the semiconductor device. The method comprising the steps of forming an interlay insulating film on a semiconductor substrate in which a lower line is formed, patterning the interlay insulating film to form an aperture unit for forming an upper line connected to the lower line, cooling the semiconductor substrate in which the aperture unit is formed at a given temperature, implementing a cleaning process using a hydrogen reduction reaction in order to remove polymer formed on the sidewall of the aperture unit and a metal oxide film formed on the lower line, implementing an annealing process in-situ within a chamber in which the cleaning process is implemented, and burying the aperture unit with a conductive material to form an upper line.

Abstract: A method for cleaning a contact area of a metal line wherein a nitride barrier layer is formed on a sidewall of an insulating interlayer within the contact area by introducing the nitrogen-based radical to the contact area, whereby it is possible to prevent a low dielectric insulating interlayer from becoming deteriorated by the redeposition of metal ions and by hydrogen radical activated during reactive cleaning, thereby maintaining a low dielectric characteristic of the insulating interlayer.

Abstract: The present invention relates to a method of forming a multi-layer conductive line in a semiconductor device. A portion of a contact of a lower conductive line is selectively etched by a given thickness. A sacrificial barrier layer is then formed on the etched portion of the lower conductive line. With this structure, oxidization of the lower conductive line or diffusion of the lower conductive line material can be prevented in a subsequent insulating film process. Also, sidewall diffusion of a lower conductive line generating in a process of cleaning a contact region is prevented by the sacrificial barrier layer. Therefore, the leakage current occurring between upper and lower conductive lines can be reduced.

Abstract: A method for fabricating a magnetic field sensor having a multi-layer structure and an RF semiconductor device equipped with it are disclosed. The method comprises: forming a barrier film on a lower layer, forming a magnetic metal film on the barrier film, forming a plurality of trenches with a desired thickness in the magnetic metal film, forming a copper film in the plurality of trenches, so that multiple layers of magnetic metal film and copper film can be formed repeatedly.

Abstract: A method for cleaning a contact area of a metal line wherein a nitride barrier layer is formed on a sidewall of an insulating interlayer within the contact area by introducing the nitrogen-based radical to the contact area, whereby it is possible to prevent a low dielectric insulating interlayer from becoming deteriorated by the redeposition of metal ions and by hydrogen radical activated during reactive cleaning, thereby maintaining a low dielectric characteristic of the insulating interlayer.

Abstract: Disclosed are apparatus and method for ultrasonically dispersing a silica sol such as is used in a process of manufacturing a silica glass by a sol-gel method. The apparatus includes a sol feeder for holding a sol to be dispersed, a sol container for containing the ultrasonically dispersed sol, a medium tank having a liquid-phase ultrasonic medium, an ultrasonic vibrator for generating ultrasonic waves within the tank, and a sol pipe for providing a sol feeding path connecting the sol feeder and the sol container to each other, the sol pipe having a portion submerged under the ultrasonic medium in the medium tank. The portion of the sol pipe submerged under the ultrasonic medium has a shape bent in a zigzagged fashion.

Abstract: A method and apparatus for guiding a vehicle in which a transmission signal of a position transmitting device installed at key points on a roadside is received by a position receiving device mounted in the vehicle. The apparatus having members for coding position information on the road where the position transmitting device is installed and traffic information including danger information with respect to the road, storing the same, modulating and continuously transmitting the coded information to the vehicle. Also, the apparatus capable of receiving the transmission signal of a corresponding position while the vehicle is moving on the road, and continuously classifying and searching the information and the intensity of the signal. Another part of the apparatus for detecting the current position of the vehicle either by directly using the searched result or by computing a travel distance of the vehicle.

Abstract: A method for collecting traffic information is described. The method includes a position information transmitting step of installing a position transmitting device at a starting point and an ending point of a link of entire road and transmitting position information of the link to probe vehicles. There is an information receiving/classifying/searching step of receiving a transmission signal of a corresponding position while traveling on a road, and continuously classifying and searching the intensity of the signal and the position information of the link. The method also includes a travel information transmitting step of detecting the position of the probe vehicles and the starting point and the ending point of the link according to the result of searching, computing a time, a distance and a speed required for traveling the link on the basis of the detected information, and transmitting the same.

Abstract: Disclosed is a method for fabricating a white LED which comprises, as a single active layer, an InGaN thin film which enables emission of white light. The InGaN thin film is constructed by taking advantage of the spinodal decomposition of the ternary compound and rapid thermal annealing. When growing the InGaN thin film on an n-type GaN formed on a sappier substrate under a growth condition, the thin film undergoes spinodal decomposition into two phases which show photoluminescence of a wavelength range from violet to blue and from green to blue, respectively, after which the surface of the thin film is thermally stabilized by rapid thermal annealing and the photoluminescence of the In-deficient phase is improved, so as to give intensive white photoluminescence to the InGaN single active layer. The LED which recruits such a single active InGaN thin film is superb in light emission efficiency and can be fabricated in a significantly reduced process steps.

Abstract: There is disclosed, in an image forming apparatus using electrophotography having a photoconductive drum rotating in a clockwise direction and at a predetermined velocity, a charging roller for uniformly charging the photoconductive drum's outer surface, and a scanner unit for scanning the photoconductive drum's charged area to form a latent image thereon, a transfer roller for preventing the photoconductive drum from being stained with toner that is manufactured to have different properties at its center than at its edges so as to prevent a large quantity of positive charges from being applied to the edges of the photoconductive drum and the edges of the charging roller which are not in contact with the paper.

Abstract: An image forming apparatus having an air flow structure capable of generating an airflow along a direction substantially perpendicular to a photosensitive drum through a charging device in order to prevent contamination of a corona wire (i.e., discharge wire). The image forming apparatus constructed according to the principles of the present invention includes a main frame having parallel side walls with a side wall having an air intake port. A cover is pivotally connected at one end of said main frame so as to allow closing and opening of the image forming apparatus and an image carrier is installed in the main frame so as to form a latent image. A ventilation fan installed at the port in the side wall generates an air flow through an air duct installed to guide the air flow.