baber/WOPTO huggingface dataset:
Patent KR-20000066853-A (KR)
Inventor: KIM JEONG JUN
IPC: H01J9/24
Filed: 1999-04-21
Abstract: PURPOSE: A structure of a plasma display panel and a method for manufacturing the same are provided to improve a strength of a barrier by restricting a bubble generated from an inner portion of the barrier. CONSTITUTION: A structure of a plasma display panel comprises a barrier(100) and a water glass layer(110). The barrier is formed continuously to one direction between two substrates. The water glass layer id applied on a surface of the barrier. The water glass contains a SiO2. A thickness of the water glass layer is 0.3 to 0.5 micrometer. A method for manufacturing the same comprises the steps of: forming a barrier on a substrate; and coating a water glass protection layer on the substrate formed with the barrier. A method for coating the water glass protection layer comprises the steps of forming the water glass protection layer by using a so-gel method and performing spin coating for the water glass protection layer on a surface of the barrier.
Patent KR-20000067081-A (KR)
Inventor: KO SUNG CHAN
IPC: G01R13/00
Filed: 1999-04-23
Abstract: PURPOSE: A communication training apparatus using a programmable logic element is provided to reduce the number of module board by using a programmable logic element instead of an analog chip or a digital chip. CONSTITUTION: A communication training apparatus using a programmable logic element comprises a signal conversion portion(210), a transmission process portion(230), a channel process portion(240), a reception process portion(250), a control portion(270), and a connection portion(220). The signal conversion portion converts an input signal to a digital signal. The transmission process portion selects one of the first control information according to a control signal of the control portion and transmits the signal transmitted from the signal conversion portion according to the selected control information. The channel process portion selects one of the second control information according to a control signal of the control portion and distorts and transmits the signal transmitted from the signal conversion portion according to the selected control information. The reception process portion selects one of the third control information according to a control signal of the control portion and distorts and transmits the signal transmitted from the channel process portion or a wireless frequency signal of an outside according to the selected control information. The control portion controls the selection of the control information. The connection portion stores temporally the signals of the transmission process portion, the channel process portion, and the reception process portion to connect the signals to a terminal.
Patent KR-19990046768-A (KR)
Title: 표면실장형인덕턴스코일
Filed: 1999-04-23
Abstract: 본 발명은 전자제품의 PCB(Printed Circuit Board)상에 표면실장이 용이하면서 누설자속에 의한 악영향이 배제되는 상태로 설계되어 치수의 소형화가 가능한 표면실장형 인덕턴스 코일에 관한 것이다. 
     본 발명에 따르면, 소정 수의 코일이 권취된 코어(12;34;54)의 중앙을 관통삽입하는 지주부가 내측 중앙위치에서 하향 연장되면서 상기 코어를 커버링하기 위한 커버부재(16;32;50)와,  그 커버부재의 지주부의 선단이 삽입고정되는 고정공이 형성됨과 더불어 상기 코어에 권취된 코일의 양단이 납땜접속되는 도전성 패턴(24;40;56a,56b)과 그 도전성 패턴에 전기적으로 연결되면서 표면실장접속을 위한 표면실장패턴(24;40;56a,56b)이 형성된 베이스부재(20;36;52)를 포함하여 구성되고, 상기 도전성 패턴은 상기 코일의 양측 접속단의 결합을 위해 상기 베이스부재의 상면에 형성되며, 상기 표면실장패턴은 표면실장을 위해 그 베이스부재의 하면에 형성되고, 상기 도전성 패턴(24;40;56a,56b)과 표면실장패턴(24;40;56a,56b)은 도전접속패턴(24b,40b,56a',56b')에 의해 상호 전기적으로 연결되도록 된 것이다.
Patent KR-19990088240-A (KR)
Title: 반도체기억장치및그제조방법
IPC: H01L21/314
Filed: 1999-05-13
Abstract: 본 발명은 리크가 작고 동시에 전하 유지능력이 높은 기억용량막을 구비한 반도체 기억장치 및 그 제조방법을 제공하기 위한 것이다. 
     화학양론적 조성비를 갖는 BST막으로 이루어지는 고 유전율층(3)과 상부전극(15) 사이에, Ti 조성비가 화학양론적 조성에서 벗어난 BST막으로 이루어지는 저 리크층(5)을 개재시켜 고 유전체층(3) 및 저 리크층(5)에 의해 기억용량막(1)을 구성한다.  Ti 조성비가 화학양론적 조성에서 벗어난 BST막은 리크 전류량을 억제하는 기능이 높고 동시에 화학양론적 조성을 갖는 BST막에 비해 비유전율(Relative dielectric constant)의 저하가 작다.  따라서 콘덴서가 직렬구조로 된 기억용량막 전체의 비유전율의 저하를 극히 작게 억제하면서 리크 전류의 억제를 도모할 수 있으므로 반도체 기억장치의 미세화를 추진할 수가 있다.
Patent KR-19990064862-A (KR)
Title: 차량자동항법장치의 교통흐름 정보 시스템
Filed: 1999-05-15
Abstract: 본 발명은 도로를 주행하는 차량에서 자동항법장치와 연계되어 도로상태, 혼잡도, 공사유무, 행사 등의 교통흐름 상태 등의 정보를 실시간으로 운전자에게 전달하여 가장 경제적인 시간에 최적의 노선을 주행할 수 있는 정보를 전달하는 시스템에 관한 것이다. 
     최단거리의 노선을 선정하였다 할지라도 시간대에 따라 교통량이 변화하는 경우나 급작스런 사고로 통행이 불편한 경우, 또는 특정한 행사로 인하여 통행을 할 수 없는 경우에 있어서는 기존의 차량항법장치는 그 효과를 전혀 발휘할 수 없다. 
     이를 위하여 본 발명에서는 차량속도 감지를 위해 측정용 카메라를 이용하여 교통량 영상을 수집하는 단계, 이 영상을 수신국으로 송신하고 차량흐름 속도를 분석하는 단계, 분석된 자료를 공중파에 의해 차량으로 송신하여 차량용 자동항법 시스템에 적용시켜 회피지로 우회하는 경로를 안내하게 하는 단계로 구성된다. 측정용 카메라는 주요 도로에 설치되어 교통흐름량 영상을 영상 수신국에 보내는 역할을 한다. 영상 수신국에서는 이 영상으로 차량의 흐름을 파악하여 평균속도를 산정하고 정해진 시간마다 차량으로 무선 송신을 하게 된다. 차량용 항법장치 시스템은 이 신호를 이용하여 회피지를 포함하지 않는 최적의 노선을 제공하여 원활한 교통량 흐름을 도모하는 것을 목적으로 한다.
Patent KR-19990088351-A (KR)
Title: 반도체장치
IPC: H01L27/04
Filed: 1999-05-18
Abstract: 본 발명은 입력 패드와 전기적으로 접속되는 고농도 확산층의 면적을 크게 하는 일 없이 서지 전류를 흡수하는 능력을 향상시키는 반도체 장치에 관한 것으로, 기준전압 V ss 에 접속된 p형 반도체 기판(10)에는 소정의 간격을 두고 제 1의 n형 고농도 확산층(21) 및 제 2의 n형 고농도 확산층(22)이 형성되고, 제 1의 n형 고농도 확산층(21)의 바로 아래 영역에는 제 1의 n형 저농도 확산층(31)이 형성되어 있는 것과 아울러, 제 2의 n형 고농도 확산층(22)의 바로 아래 영역에는 제 2의 n형 저농도 확산층(32)이 형성되어 있다. 제 1의 금속층(51) 및 고저항 도전층(60)은 입력 패드(INP)와 제 1의 n형 고농도 확산층(21)을 접속하고, 제 2의 금속층 (52)은 기준전압 V ss 를 공급하는 기준전압 패드(VSP)와 제 2의 n형 고농도 확산층 (52)을 접속하고 있다.
Patent KR-19990064879-A (KR)
Title: 산업폐기 암석재를 이용한 재생 토사의 제조방법
Filed: 1999-05-18
Abstract: 본 발명은 산업폐기 암석재를 이용한 재생 토사의 제조방법에 관한 것이다. 
     종래 유리 공장, 소다회 공장 등에서 다량 발생되는 폐석회와 건축물 철거 현장에서 발생되는 콘크리트 폐기물은 그대로 매립 폐기하게 되는 것이 통례로서 그대로 토양에 매립 할 경우 환경을 오염시키는 문제점이 있었다. 
     본 발명은 상기에서와 같이 환경에 악영향을 주게되며 앞으로 더욱 그 발생 량이 점점 증가 추세에 있는 건축물 철거 재와 공장에서 발생되는 폐석회 등 산업폐기물 암석재를 이용하여 오염 물질이 없는 재생 토사로 재생산하여 매립지의 지반, 연약지반, 도로 기층재, 건축 지반을 다지는 지반 재로 활용하는 동시에 식물 재배용 양질의 토양으로 사용 할 수 있도록 하고, 분쇄, 세척에 의하여 얻어진 모래와 자갈 왕모래는 콘크리트 재료로 재활용 하므로써 환경을 보호하고 유용한 자원으로 재활용 할 수 있도록 한 것이다.
Patent KR-20000075145-A (KR)
Title: Semiconductor package
Inventor: KIM BEOM JUN
IPC: H01L23/13
Filed: 1999-05-29
Abstract: PURPOSE: A semiconductor package is provided to minimize the semiconductor package in size, by stacking an inner lead of a lead frame on another lead so that the area occupied by the inner lead is greatly reduced. CONSTITUTION: A semiconductor package comprises a lead frame(200), a semiconductor chip(300), a wire and molding resin(400). The lead frame includes a lead and a die pad. The lead is composed of a plurality of the first leads(220), second lead(230) and third lead(240). The pluralities of the first leads have an inner lead and an outer lead. The second lead is insulated and has at least one layer on the inner lead. The third lead is established in the first leads and is composed of an inner lead and an outer lead. The third lead is shorter than the first lead. The semiconductor chip includes a plurality of bonding pads, formed on the die pad. The wire electrically connects one of the bonding pads with the inner lead of the first lead, electrically connecting one of the other bonding pads with the second lead, and electrically connecting the second lead with the third lead. The molding resin molds the lead frame, the semiconductor chip and the wire.
Patent KR-20010002444-A (KR)
Inventor: KWON HYEOK JUN
IPC: G11C11/401
Filed: 1999-06-15
Abstract: PURPOSE: A circuit is provided to prevent a data output skew of a semiconductor memory device. CONSTITUTION: The device includes the following parts: a plurality of multiplexers(MUX1,MUX2,MUX3) outputting data stored in memory cells selectively; latch circuits each of which corresponds to the multiplexers and latches data from the multiplexers; output circuits each of which corresponds to the latch circuit and outputs data from the latch circuit to the external of the semiconductor memory device; and data lines each of which is connected between the latch circuit and the output circuit. The latch circuit latches data being inputted from the multiplexer for a time inversely proportional to the length of the corresponding data line. Each latch circuit includes buffers(111,112,121,122,131,132), and each buffer comprises two transistors. The transistors have different sizes each other, and the size of the transistors is proportional to the length of a data line between the multiplexers and output buffers(B1-Bn).
Patent KR-20010003287-A (KR)
Inventor: PARK SEONG JO
IPC: H01L27/108
Filed: 1999-06-22
Abstract: PURPOSE: A method for manufacturing a semiconductor device is provided to prevent a time delay phenomenon and to sufficiently charge a memory cell capacitor, by increasing a junction area where a storage node or bit line contacts a transistor, and by reducing a storage node contact resistance to shorten a time constant in a read/write operation. CONSTITUTION: A transistor has an impurity diffusion region in an active region of a semiconductor substrate(20), including a gate insulating layer(21), a cap insulating layer(24) and a side wall spacer(25) on a gate formation region of the semiconductor substrate. Only a predetermined portion of the impurity diffusion region adjacent to the side wall spacer is exposed, and the rest is covered with an insulating layer. A predetermined depth of the exposed impurity diffusion region is removed to form a contact portion. A contact plug is formed in the contact portion.
Patent KR-20010004472-A (KR)
Inventor: KIM TAE HAN
IPC: B60Q5/00
Filed: 1999-06-29
Abstract: PURPOSE: A horn switch installing structure prevents the wrong operation of a horn switch due to the contact of the contacts of upper/lower switch panels, respectively. CONSTITUTION: A horn switch installing structure comprises a plate(200), upper/lower switch plates(300a,300b) and an air bag cover(100). The plate(200) has a receiving concave portion(220) having protruded protrusion(221) and a connecting hole(210) on one side thereof. The upper/lower switch plates(300a,300b) have contacts received on the protrusion(221) and for generating horn sounds. The air bag cover(100) has a connecting pin(110) protruded on the inner surface and fitted to the connecting hole(210) of the plate(200).
Patent KR-20010005182-A (KR)
Inventor: AHN MYEONG GYU
IPC: H01L21/3205
Filed: 1999-06-30
Abstract: PURPOSE: A method for forming a polycide wiring of a semiconductor device is provided to improve device characteristic by removing fine oxides without an additional process. CONSTITUTION: A polysilicon layer(3) and a transition metal silicide layer(4) are stacked on a completed structure after finishing predetermined processes. A mask pattern is formed on the transition metal silicide layer(4). A fine oxide(6) generated a boundary portion between the transition metal silicide layer(4) and the polysilicon layer(3) is exposed by etching the exposed transition metal silicide layer(4). The fine oxide(6) is removed by using an in-situ plasma etching process with an etching selection ratio similar to the polysilicon layer(3). A wiring is formed by etching the exposed polysilicon layer(3).
Patent KR-20010009256-A (KR)
Inventor: SHIN HYEON JAE
IPC: B65D6/00
Filed: 1999-07-08
Abstract: PURPOSE: A tube-case transferring box and a tube-case supplying device are provided to simplify work by transferring the tube-case in a box to a supply board for the tube-case, and prevent the occurrence of supply failure. CONSTITUTION: In a tube-case transferring box, a projected part(22) is formed outward in the edge of an upper end, and a cover(1) having an engaging part(12) and a locking device(11) installed to be hung and fixed on the projected part is bound on the upper part. And a discharge gate(21) is formed in the lower side of the side part of the box, installed in a diaphragm(41) of a tube-case supply board(4), to discharge tube-cases(3) one by one through the gate(21). In a tube-case supplying device, the tube-case supply board is successively sloped in order that the tube-case laid in the inside of a body(2) is discharged through the discharge gate. A tube-case interrupting board(47b) operated by a motor(46) is installed in the front area of the discharge gate to supply the tube-case one by one. And a cylinder(48) is installed in the front area to put the supplied tube-case on stand-by and supply again to a lower part, and a tube standing device(51) is installed to supply the tube-case supplied from the cylinder(48) in the raised state.
Patent KR-20010018459-A (KR)
Inventor: LEE HYUNG SOO
IPC: A47K3/26
Filed: 1999-08-19
Abstract: PURPOSE: A counterflow preventing valve of a shower head is provided to easily change the direction of a valve seat when the counterflow preventing valve is inserted into a cold water pipe or a connection hole of the cold water pipe. CONSTITUTION: A counterflow preventing valve of the shower head includes a first cylindrical housing(1), a second cylindrical housing(2) and a valve seat(3). The first cylindrical housing has a round plate(11) formed at a front portion, a plurality of water passing holes(12) formed in a circumference of the round plate, and a spiral part(13) formed at a rear outer surface. The second cylindrical housing has a tap hole(21) coupled with the spiral part of the first cylindrical housing, a round plate(22) formed at a rear portion, a plurality of water passing holes(23) formed in a circumference of the round plate and an end part(24) mounting a round packing(4) to a rear outer side. The valve seat is mounted inside of the first and second cylindrical housings, and has a conic cap(31) and a plurality of legs(32) formed on an outer surface of the cap.
Patent KR-20010019547-A (KR)
Inventor: AHN HWA SIK
IPC: G11B7/09
Filed: 1999-08-27
Abstract: PURPOSE: A method for discriminating a type of an optical disk is provided to exactly discriminate the type of the optical disk by using a size of a focus error signal from the optical disk. CONSTITUTION: A focus error signal is detected by moving an object lens at right angles to an optical disk. A size of the focus error signal is stored. The size of the focus error signal is detected again by changing a mode. A type of the optical disk is discriminated by accumulating the re-detected size of the focus error signal and the stored size of the focus error signal. Thereby, various types of optical disks are discriminated exactly.
Patent KR-20000022834-A (KR)
Inventor: MURADE MASAO
IPC: G02F1/1343
Filed: 1999-09-01
Abstract: PURPOSE: A driving circuit for an electrical optical system is provided to be capable of being a large size of an image display area by using a substrate region efficiently. CONSTITUTION: On a substrate of a liquid crystal apparatus is formed a sampling circuit for sampling an image signal and a data line driving circuit. The data line driving circuit supplies a sampling control signal every sampling switch(302) which connected to a plurality of data lines arranged adjacent to each other. The data line driving circuit comprises a buffer circuit(500) which has inverters(501-503) having a thin film transistor. The thin film transistor shapes a transfer signal inputted from a shift transistor circuit(400) to output the shaped signal as the sampling control signal. The thin film transistor comprises a channel portion having a channel width which is identical to a width of data lines.
Patent KR-20000023414-A (KR)
Inventor: HIRAI SMIE
IPC: H05K1/00
Filed: 1999-09-22
Abstract: PURPOSE: A method for manufacturing a semiconductor is provided to reduce an area necessary for a printed circuit board and then reduce the cost for the board by arranging coating lead wires on a removal area for a bonding connection. CONSTITUTION: An electrolytic plating is performed on an external input/output terminal portion (20) and a bonding pad(21a) while supplying power source from a coating lead wire(19) of a circuit board(4a). A window portion is formed by removing the coating lead wire(19) and an area corresponding to a center pad of a semiconductor chip. An insulating film is attached on the semiconductor chip for the center pad to be exposed from the window portion. The bonding pad(21a) and the center pad are connected by bonding wire. External input/output terminals(20) are formed on the external input/output portion.
Patent KR-20000028825-A (KR)
Inventor: SHIMIZ HIROSHI
IPC: G11C29/04
Filed: 1999-10-05
Abstract: PURPOSE: A semiconductor device is provided to reduce or remove detour wiring for minimizing the wiring area and shortening the delay time of signal electric wave. CONSTITUTION: A fuse is cut by a laser to the fuse in fuse circuits in order that the output value of fuse circuits(311-316) is one when there is a bad memory cell among the memory block of a memory circuit(20). Also the fuse circuit unit(317) is cut by the laser. Then, the output value from the fuse circuit becomes i when power is on. The output signal Pi of a main decoder(33) is a high level and the other is a low level. Therefore, the output signals Q1 to Q(i-1) of a memory circuit are low levels and signal Qi to Q36 are high levels. The conversion circuit in the memory circuit shifts the contacting point of a data input and output unit in a block unit, by responding the output so that a memory block(2-i) is not used. Hence, memory blocks(2-(i+1) to 2-37) are used instead of memory blocks(2-i to 2-36). Wiring is prohibited on the fuse and the upper layer around the fuse in order not to be affected by laser irradiation.
Patent KR-20010036735-A (KR)
Inventor: KIM HONG GYU
IPC: G06F7/544
Filed: 1999-10-11
Abstract: PURPOSE: An apparatus and a method for processing data for performing an arithmetic calculating with difference word length are provided to offer a data processing for a multi media application in low electric power, low cost and high performance. CONSTITUTION: A SOC type pipe line host processor system(10) comprises a pipe line host processor(12) as a general micro controller or a micro processor and a pipe line fixing decimal dot DSP(14) as a coprocessor. The host processor(12) performs normal control functions. The DSP(14) performs additional specific digital signal processing functions as a mixture and comparison of a signal. A data memory(38) as a program memory(36) as a ROM, a RAM, an EPROM, EEPROM or flash EEPROM a DRAM or SRAM are provided. The program memory(36) and the data memory(38) store instructions and data items, respectively. The data memory(38) has a "X" data memory(40) and a "Y" data memory(42). The system(10) includes program memory buses(16) and data memory buses(22). The program memory buses(16) includes an address bus(18) PAB is displayed therein and a data bus PDB is displayed therein. The address bus(18) and the data bus are connected between the host processor(12) and the program memory(36). The system(10) includes a clock generation circuit(44) receiving a clock signal applied from the exterior and generating two the first and second internal clock signals(CLK1, CLK2) being synchronized to an external clock signal(CLK).
Patent KR-20000047545-A (KR)
Inventor: IWAOHIDEMI
IPC: H01F27/28
Filed: 1999-10-20
Abstract: PURPOSE: A multiple layer electronic component is provided to manufacture plurality of multiple layer electronic components having different inductance values by using a ceramic green sheet of same thickness. CONSTITUTION: A multiple layer electronic component includes a multiple layer assembly(11), an inner electrode(5a-5d), and an outer layer(14). The multiple layer assembly(11) includes a plurality of ceramic layers(1,1'). The inner electrode(5a-5d) is implemented between the ceramic layers and is connected to the inner portion of the multiple layer assembly. The outer layer(14) is provided on one terminal of the multiple layer assembly so as to be connected to some of the inner electrode(5e,5d). The ceramic layer(1') does not have an inner electrode(5a-5d) which is implemented between the ceramic layers(1,1'). The component according to the present invention further includes a connector which connects the inner electrodes formed on the ceramic layer(1,1') in a coil-like shape.
Patent KR-20010037834-A (KR)
Title: Secondary battery
Inventor: SEO HYEON MI
IPC: H01M10/02
Filed: 1999-10-20
Abstract: PURPOSE: A secondary battery is provided which rapidly and evenly supplies an electrolytic solution to each pole pate by having a dispersion tube being able to evenly supply the electrolytic solution to the inside of a case. CONSTITUTION: The secondary battery comprises: (i) a case(10) which has a space part(11), where an electrolytic solution is filled up, and is covered up by an upper cover(12) which has a vent(60) to discharge gas generated from the inside to the outside; (ii) plural pole plates(20) which are arranged on the space part horizontally; (iii) terminals of the anode and the cathode(40, 50) which are electrically connected with the pole plates by an anode tap(41) and a cathode tap(51) and exposed on the upper side of the case; and (iv) a dispersion tube(70) which has an injection hole(71), where the electrolytic solution injected from the outside of the case is supplied and plural discharge holes(73) which are connected with the injection hole and are formed along the direction of the arrangement of the pole plates.
Patent KR-20000006720-A (KR)
Inventor: CHANG HWANG JIN
Filed: 1999-10-27
Abstract: PURPOSE: A mileage system is provided to prevent a gain of an internet home page from being reduced inducing a re-investment of a mileage point. CONSTITUTION: The mileage system comprises an internet server(4), an internet home page(8) and a stock exchange site(14). A data base(2) of a client is build in the internet server(4). Various banner advertisements, merchandise icons(6), or link buttons(16) are disposed in the internet home page(8) which is loaded at the internet server(4). The internet home page(8) reserves a predetermined mileage point to the data base(2) of a corresponding client when the client clicks the icon(6) or the link button(16) or buys a merchandise. The stock exchange site(4) is disposed or linked to the internet home page(8) and exchanges the client's mileage with a stock of a company operating the home page(8).
Patent KR-20000067802-A (KR)
Inventor: LEE JONG HWA
IPC: B21D13/00
Filed: 1999-11-08
Abstract: PURPOSE: A bending apparatus for a corrugated steel plate is provided to prevent proof load from being reduced by forming a complete curvature by using corrugated rollers. CONSTITUTION: A bending apparatus for a corrugated steel plate includes a supporting frame(710); a feeding motor(712) installed on the supporting frame, a converting unit(714) converting rotary force of the feeding motor into horizontal transferring force; a feeding rod(716) horizontally transferred by the converting unit, a bottom frame(720) connected with the supporting frame; a pair of side frames(722) straightly installed at both sides of the bottom frame; a first corrugated roller(732) rotatably supported by both side frames and forming corrugation matching with corrugation formed in a steel plate(100); a first roller motor installed in one side frame for rotating the first corrugated roller, each pair of first, second, and third lifting cylinders(742,752,762) installed at both side frames in the lower part of the first corrugated roller; second, third, and fourth corrugated rollers(740,750,760) rotatably supported by first, second, and third lifting cylinders and each forming corrugation matching with the corrugation formed in the steel plate; and second, third, and fourth roller motors installed in each pair of first, second, and third lifting cylinders for rotating the second, third, and fourth corrugated rollers.
Patent KR-20010046529-A (KR)
Inventor: CHOI JIN BANG
IPC: H01L21/68
Filed: 1999-11-12
Abstract: PURPOSE: A method and an apparatus for holding a semiconductor wafer is provided to let a fuzzy gas which flows from a bent groove flow toward an edge direction of a wafer during a vacuum absorption of the wafer. CONSTITUTION: An apparatus for holding a semiconductor wafer comprises an upper surface(12a), a vacuum groove(14) and a vent groove(16). The outside surface of the upper surface(12a) on which the wafer is loaded is coarser than the inside so as to guide the flow of a nitrogen gas floured from the vent groove(16). The vacuum groove(14) is formed on the upper surface(12a) and absorbs the vacuum of the wafer. The vent groove(16) is formed on the edge and let the nitrogen gas flow toward the back side.