Industrial Technology Research Institute

National Yang Ming Chiao Tung University

Episil Technologies Inc.

National Science Council

Grand Plastic Technology Corporation Taiwan

Bing-Yue Tsui

Jui-Cheng Wang

Chin Chiu Hsia

Tsung-Ju Yang

Tsung Yao Chu

Li-Tien Hsueh

Chih-Feng Huang

Fang-Hsin Lu

Hun-Jan Tao

Cheng-Chung Lee

Ming-Huan Tsai

Pei-Yu Wang

Baw-Ching Perng

Chih-Cheng Wang

Chun-Tao Lee

Kuan-Lun Chang

Tzung-Zu Yang

Mao-Chieh Chen

Hsieh Yue Ho

Hsiao Shih-Yi

Kang Tsung-Kuei

Jiunn-Yann Tsai

Jui-Tse Hsiao

Jann-Shyang Liang

Yi-Ting Shih

A gate fabrication method of an UMOSFET and a trench gate structure formed thereof are provided, comprising providing a transistor structure and a lithography process is employed to define a trench region. A gate oxide layer is deposited along the trench and two polysilicon sidewalls having a spacing there in between are formed afterwards. A wet etching is used to remove the gate oxide layer underneath the polysilicon sidewalls such that a vacancy is formed at the trench bottom. By oxidizing the polysilicon sidewalls, a thick oxide layer is formed, enfolding periphery of the polysilicon sidewalls and filling the vacancy. The spacing can be alternatively retained between the polysilicon sidewalls covered with the thick oxide layer, such that the trench can be alternatively filled. The present invention is effective in increasing oxide thickness of the gate bottom, reducing the trench corner curvature as well as the feedback capacitance.

Gate fabrication method of an U-metal-oxide-semiconductor field-effect transistor and trench gate structure formed thereof

A method for reducing parasitic junction field effect transistor resistance, applicable to a high power device having a semiconductor substrate layer, is provided, including providing a plurality of hard masks on a top surface of the semiconductor substrate layer. Each hard mask has a bottom plane and a tilt sidewall such that an acute angle is formed there in between. A body ion implantation process is subsequently performed, so a body region is formed between two adjacent hard masks. The body region has an upper and a lower surface. A width of the upper surface is greater than that of the lower surface. Therefore, the present invention achieves to control a parasitic JFET region characterized by having a wider bottom and a narrower top, thereby reducing its resistance thereof. Meanwhile, since a bottom angle of the body region is increased, breakdown voltage of the device is increased as well.

Method for reducing parasitic junction field effect transistor resistance

A process method for fabricating a three-dimensional source contact structure is provided, which is applicable to form a step-like three-dimensional source contact structure in a MOSFET of a power device. The proposed method sequentially adopts a lithography process and a shallow trench process to form a metal contact window. And a lateral etching process, or spacers which will be removed eventually, can be alternatively provided for increasing horizontal surface contact when depositing a source contact metal. Meanwhile, a longitudinal surface exposed by the shallow trench process is also beneficial to increase vertical contact when depositing the source contact metal. As a result, a step-like three-dimensional source contact structure can be formed by employing the present invention. It is believed that the present invention achieves in reducing cell pitch effectively and can be widely applied to various power devices having MOSFET structure thereof.

Process method for fabricating a three-dimensional source contact structure

A source-body self-aligned method of a VDMOSFET is provided. A pad layer and an unoxidized material layer are sequentially formed on an epitaxial layer on a semiconductor substrate. A lithography process is then carried out for patterning. Later, a thermal oxidation process is employed such that the unoxidized material layer is oxidized to form oxidation layers. Then, a source ion implantation process is performed, and a wet etching is used to remove the oxidation layers before successively employing a body ion implantation process. By using the process method disclosed in the present invention, it achieves to form the source region and the body region which are self-aligned. Meanwhile, since process complexity of the invention is relatively low, process uniformity and process cost can be optimally controlled. In addition, the invention achieves to reduce channel length and on-resistance, thereby enhancing the reliability effectively.

Source-body self-aligned method of a vertical double diffused metal oxide semiconductor field effect transistor

A method for increasing an oxide thickness at trench corner of an UMOSFET is provided, comprising providing an N-type substrate, and forming an N-type drift region, N-type and P-type heavily doped regions and P-type body therein. A trench is defined through lithography, and a pad oxide is formed along the trench through oxidation or deposition process. An oxidation barrier is formed upon the pad oxide. A thermal oxidation process is employed, so a corner oxide is effectively formed at the trench corner. After removing the pad oxide and oxidation barrier, various back-end processes are carried out to complete the transistor structure. The invention is aimed to increase oxide thickness near the trench bottom, and can be applied to high voltage devices, such as SiC. The conventional electric field crowding effect occurring at the trench corner is greatly solved, thus increasing breakdown voltages thereof.

Method for increasing an oxide thickness at trench corner of an U-shaped gate metal-oxide-semiconductor field-effect transistor

A structure of trench transistors includes the following elements. A substrate serves as a drain of the structure of trench transistors. An epitaxial layer is disposed on the substrate. A plurality of trenches are disposed in the epitaxial layer. A plurality of gate insulator layers are respectively disposed on the inner surfaces of the trenches. A plurality of gates are respectively disposed on the gate insulator layers. A plurality of first base regions are respectively disposed in the epitaxial layer between the adjacent trenches, and have a first depth from the top surface of the epitaxial layer. A plurality of second base regions are respectively disposed in the epitaxial layer adjacent to the sidewalls of the trenches, and each has a second depth from the bottom surface of the first base region. A plurality of sources are respectively disposed in the first base region beside the sidewalls of the trenches.

Semiconductor structure of trench transistors and manufacturing method thereof

An enhanced tunnel field effect transistor includes a substrate, a layer of P-I-N structure, a hetero-material layer, a gate dielectric layer, a gate structure and a spacer, in which the layer of P-I-N structure is disposed on the substrate, the hetero-material layer is disposed on portion of the layer of P-I-N structure, the gate dielectric layer is disposed on the hetero-material layer, the gate structure is disposed the gate dielectric layer and a spacer is disposed on a sidewall of the hetero-material layer, the gate dielectric layer, and the gate structure. The hetero-material layer can increase the tunneling efficiency of the enhanced tunnel field effect transistor to increase the conductor current to improve the enhanced tunnel field effect transistor performance.

Enhanced tunnel field effect transistor

A method of fabricating an MOS device is described. A substrate doped a first type dopant is provided as a drain. A first type epitaxial layer is formed on the substrate and is patterned with a trench to form several islands. A gate dielectric layer is then formed on the surface of the trench, and a gate is formed in the trench covering the gate dielectric layer. A second type dopant is doped into the islands with the doping concentration decreasing gradually from the bottom to the top of the islands. Afterwards, a source is formed at the top of the islands. Accordingly, the doping concentration in the islands decreases gradually from the drain to the source with the highest doping concentration near the drain. Therefore, the width of the depletion region can be reduced, and the length of the device channel can be reduced for lowering channel resistance and gate capacitance.

Method of fabricating metal oxide semiconductor device

A method of fabricating an MOS device is described. A substrate doped a first type dopant is provided as a drain. A first type epitaxial layer is formed on the substrate and is patterned with a trench to form several islands. A gate dielectric layer is than formed on the surface of the trench, and a gate is formed in the trench covering the gate dielectric layer. A second type dopant is doped into the islandswith the doping concentration decreasing gradually from the bottom to the top of the islands. Afterwards, a source is formed at the top of the islands. Accordingly, the doping concentration in the islands decreases gradually from the drain to the sourcewith the highest doping concentration near the drain. Therefore, the width of the depletion region can be reduced, and the length of the device channel can be reduced for lowering channel resistance and gate capacitance.

Metal oxide semiconductor device

A method of fabricating an MOS device is described. A substrate doped a first type dopant is provided as a drain. A first type epitaxial layer is formed on the substrate and is patterned with a trench to form several islands. A gate dielectric layer is than formed on the surface of the trench, and a gate is formed in the trench covering the gate dielectric layer. A second type dopant is doped into the islands with the doping concentration decreasing gradually from the bottom to the top of the islands. Afterwards, a source is formed at the top of the islands. Accordingly, the doping concentration in the islands decreases gradually from the drain to the source with the highest doping concentration near the drain. Therefore, the width of the depletion region can be reduced, and the length of the device channel can be reduced for lowering channel resistance and gate capacitance.

The present invention discloses an electrode structure of a light emitted diode and manufacturing method of the electrodes. After formed a pn junction of a light emitted diode on a substrate, a layer of SiO2 is deposited on the periphery of the die of the LED near the scribe line of the wafer, then a transparent conductive layer is deposited blanketly, then a layer of gold or AuGe etc. is formed with an opening on the center of the die. After forming alloy with the semiconductor by heat treatment to form ohmic contact, a strip of aluminum (Al) is formed on one side of the die on the front side for wire bonding and to be the positive electrode of the LED. The negative electrode is formed on the substrate by metal contact. Another form of the electrode structure of the present invention is making both the positive and negative electrodes on the front side of the LED by etching the p-type semiconductor of the pn junction and forming a strip of negative electrode on the n-type semiconductor, the positive electrode is formed on the p-type semiconductor.

Method for wet etching of high k thin film at low temperature

The present invention provides a structure of Metal Oxide Semiconductor Field Effect Transistor (MOSFET), which comprises a SOI (Silicon-On-Insulator) device, a MOS (Metal Oxide Semiconductor) formed on said SOI device, and a metal-silicide layer. Said SOI device includes a substrate, an insulation layer formed on said substrate, and a silicon layer formed on said insulation layer, and the MOS is formed on said SOI device. The metal-silicide layer is formed in accordance with a metal aligned process by a metal layer being deposited on said SOI device and on said MOS for reacting with said silicon layer, and an implant-to-silicide process is employed to form a high-density source region and a high-density drain region for modifying Schottky Barrier and diminishing Carrier Injection Resistance.

Structure of metal oxide semiconductor field effect transistor

A method for increasing the capacity of an integrated circuit device. The method includes the steps of defining a catalyst area on a substrate, forming a nanotube, nanowire, or nanobelt on the catalyst area, forming a first dielectric layer on the nanotube, nanowire, or nanobelt and the substrate, and forming an electrode layer on the first dielectric layer. According to above method, the capacity is substantially increased without extending the original bottom area of the capacitor electrode by using the surface area of the nanotube, nanowire, or nanobelt as the area of the capacitor electrode.

Method for increasing the capacity of an integrated circuit device

A bonding pad that has low parasitic capacitance and that transmits little or no stress to the underlying metal layer during bonding, along with a process for manufacturing it, is described. A key feature of this structure is that the damascene wiring directly below the bonding pad has been limited to its outer edges, that is it is formed in the shape of a hollow square. This limits overlap by the aluminum pad of the damascene wiring to the via hole area only. After a passivation layer, including suitable diffusion barriers, has been laid over the structure, it is over-filled with a suitable soft metal (typically copper or one of its alloys) and then planarized in the usual way. A via hole for communicating with the damascene wiring is then formed. This via can take the shape of a somewhat smaller hollow square or it can be formed from a series of individual vias arranged in the shape of a broken hollow square.

Bonding pad and method for manufacturing it

Using current technology, the only way to further increase device density is to decrease device pitch. The present invention achieves this by introducing a sidewall doping process that effectively reduces the source width, and hence the pitch. This sidewall doping process also eliminates the need for a source implantation mask while the sidewall spacer facilitates silicide formation at the source, the P body contact, and the polysilicon gate simultaneously. Since the source and P body are fully covered by silicide, the contact number and contact resistance can be minimized. The silicided polysilicon gate has a low sheet resistance of about 4-6 ohm/square, resulting in a higher operating frequency.

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Hsinchu, Taiwan

Bing-Yue Tsui