Electronics and Telecommunications Research Institute

Korea Telecom

Other

Nam Hwang

Sang Hwan Lee

Min Kyu Song

Cheon-Soo Kim

Seong-Su Park

Hee Tae Lee

Min-Kyu Song

Jung-Woo Park

Seong Su Park

Hyun-Kyu Yu

Kwang Eui Pyun

Dong-Goo Kim

Sang-Hwan Lee

Seung-Goo Kang

Jong-Tae Moon

Seung Goo Kang

Hee-Tae Lee

Gwan Chong Joo

Hyun-Kyu Yoo

A device structure of a LDMOSFET has trench type sinker formed using a trench process. A semiconductor layer of a first conductive type is formed within the device structure. A field area is formed in a trench structure on one side of the semiconductor layer and a gate electrode is formed on a given surface of the semiconductor layer. A channel layer of a second conductive type is formed by laterally diffusion from the field area to a width containing both sides of the gate electrode. The source area of LDMOS is electrically connected with the substrate through the sinker. By a piercing through the source area, the sinker divides the source area into two source areas. This division reduces the parasitic resistance as well as parasitic capacitance. In addition, the device structure eliminates the need for high temperature diffusion process and reduces lateral diffusion of the sinker.

Device structure of RF LDMOS with trench type sinker

A method of forming an HF power device. The method includes forming a semiconductor layer as a first conductive type on a semiconductor substrate; etching the semiconductor layer forming a first trench; doping an impurity in the neighborhood of the first trench forming a first impurity layer; burying a conduction film into the first trench; etching the semiconductor layer forming a second trench; forming a field oxide film buried into the second trench; forming a gate electrode on a surface of the semiconductor layer; forming a source on the surface of the semiconductor layer; forming a drain area on the surface of the semiconductor layer; forming an LLD area on the surface of the semiconductor layer between the drain area and the gate electrode; forming a first metal electrode; and forming a second metal electrode electrically connected to the LDD area.

Method of making a HF LDMOS structure with a trench type sinker

The present invention relates to an optical integrated circuit; and, more particularly, to a method for preparing an improved hybrid optical integrated circuit which is capable of accommodating optical waveguides, optical devices, such as light emitting devices and light receiving devices, and optical fibers in an effective manner. The present invention has the advantages of minimizing horizontal misalignment error between the SOI waveguide rib area, the V-groove etch window and the alignment marks, decreasing the manufacturing cost by passively aligning the waveguides, the optical devices and the optical fibers on a single substrate. Also, the present invention has an effect of reducing fresnel reflection loss by providing the LPCVD silicon nitride layer capable of being used as an anti-reflection coating layer at both ends of the waveguide.

Method for fabricating a hybrid optical integrated circuit employing SOI optical waveguide

An optical switch module for aligning and fixing an optical fiber array relative to an optical switch device includes an optical fiber support member for fixing the optical fiber array; a first support device forming a homo-junction with the optical fiber support member and including a first thermal deformation buffer device; and a second support device forming a hetero-junction with the first support device to support the first support device and including a second thermal deformation buffer device.

Optical switch module having a buffer device for minimizing a post welding shift

Disclosed is a micromirror for a hybrid optoelectronic integrated circuit, a method for manufacturing the same, a micromirror-photodetector assembly and an assembly of hybrid optoelectronic integrated circuit for receiving light. The micromirror the present invention comprises a silicon substrate and at least one V-shaped groove formed in the silicon substrate and the V-shaped groove has an inclined surface reflecting light emitted from an optical waveguide to a photodetector. The alignment of the photodetector and the optical fibers is achieved without an additional attachment equipment, by inserting the optical fibers into the V-groove.

Micromirror for a hybrid optoelectronic integrated circuit, a method for

An improved optical module having lenses aligned on a lens-positioning V-groove and a fabrication method thereof which includes a silicon substrate, which defines a light transfer path below a surface thereof, including light transferring V-grooves and a light receiving V-groove, and lens-positioning V-groove for determining the position of a lens, wherein two lens-positioning V-grooves are formed therein, an optical transmitter module including a laser which is a light source and is flip-chip-bonded to the substrate by a solder bump after an optical waveguide is previously aligned with the V-groove by using an alignment mark behind the vertical portion of the light transferring v-groove. A light transferring lens attached on one lens-positioning V-groove for condensing the light from the laser, and a laser monitoring optical detector arranged on a side wall opposite the laser of the light transferring V-groove, wherein an active region is flip-chip-bonded toward the substrate, for monitoring the laser, and an optical receiver module including a light receiving lens attached on the lens-positioning V-groove of the silicon substrate for condensing beam externally transferred thereto, and a light receiving optical detector attached to the light receiving lens for detecting beam externally transferred thereto, wherein the optical transmitter module and the optical receiver module are arranged in the same silicon substrate.

Optical module having lenses aligned on lens-positioning V-groove and

The present invention relates to an accurate method using laser welding for mounting an optical focusing lens utilized in a semi-conductor laser module for optical transmission and optical amplification through an optical fiber and a laser module so produced. The laser module includes an aligned laser diode, a lens fixture mounting the laser diode, a focusing lens mounted within a lens housing which in turn is mounted by a lens ring to the lens fixture. In the method, the steps include aligning mutual positions between the laser diode and the optical focusing lens in the vertical and horizontal directions so that the magnitude of the optical signal output from the optical fiber is maximized after the distance between the optical focusing lens and the optical fiber is adjusted and fixed to obtain a maximum optical coupling efficiency between the laser diode and the optical fiber. Next a laser-welding step is performed at an interval between the lens housing and the lens ring. The mutual positions between the laser diode and the optical focusing lens are aligned in the vertical and horizontal directions so that the magnitude of the optical signal output from the optical fiber is maximized. Finally a laser-welding step is performed at an interval between the lens fixture and the lens ring.

Laser module with focusing lens and fixing method of the focusing lens

Growing community of inventors

Daejeon, South Korea

Nam Hwang