KR19980037916A - Wet etching equipment for semiconductor manufacturing - Google Patents
Wet etching equipment for semiconductor manufacturing Download PDFInfo
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- KR19980037916A KR19980037916A KR1019960056738A KR19960056738A KR19980037916A KR 19980037916 A KR19980037916 A KR 19980037916A KR 1019960056738 A KR1019960056738 A KR 1019960056738A KR 19960056738 A KR19960056738 A KR 19960056738A KR 19980037916 A KR19980037916 A KR 19980037916A
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Abstract
웨이퍼를 균일하게 식각 또는 세정할 수 있는 반도체 제조용 습식식각장치에 관한 것이다.A wet etching apparatus for manufacturing a semiconductor capable of uniformly etching or cleaning a wafer.
본 발명은, 웨이퍼가 적재된 복수의 캐리어가 투입되고 일정량의 케미컬이 담길 수 있는 내부저장조와, 상기 내부저장조를 포함하고 상기 내부저장조에서 오우버플로우되는 상기 케미컬이 저장되는 외부저장조와, 상기 외부저장조의 저면에 형성된 케미컬 방출구와 상기 내부저장조의 저면에 형성된 케미컬 공급구를 연결하며 중간에 펌프가 개재된 순환라인을 구비하는 반도체 제조용 습식식각장치에 있어서, 상기 케미컬 공급구는 상기 내부저장조의 저면에 복수개 형성됨을 특징으로 한다.The present invention includes an internal storage tank into which a plurality of carriers on which a wafer is loaded and into which a predetermined amount of chemical is contained, and an external storage tank including the internal storage tank and storing the chemicals overflowed from the internal storage tank, and the external storage tank. In the wet etching apparatus for manufacturing a semiconductor, comprising a circulation line with a pump interposed between the chemical discharge port formed on the bottom of the reservoir and the chemical supply port formed on the bottom of the reservoir, the chemical supply port is provided on the bottom of the internal reservoir It is characterized in that a plurality is formed.
따라서, 내부저장조 내부에서 케미컬이 회전하는 와류현상이 발생하지 않아 웨이퍼가 균일하게 식각 또는 세정될 수 있는 효과가 있다.Therefore, the vortex phenomenon in which the chemical rotates inside the internal storage tank does not occur, and thus the wafer may be uniformly etched or cleaned.
Description
본 발명은 반도체 제조용 습식식각장치에 관한 것으로서, 보다 상세하게는 웨이퍼를 균일하게 식각 또는 세정할 수 있는 반도체 제조용 습식식각장치에 관한 것이다.The present invention relates to a wet etching apparatus for manufacturing a semiconductor, and more particularly, to a wet etching apparatus for manufacturing a semiconductor capable of uniformly etching or cleaning a wafer.
일반적으로, 반도체소자 제조공정은 습식식각공정 및 세정공정이 많이 수행된다.In general, a semiconductor device manufacturing process is performed by a wet etching process and a cleaning process.
습식식각공정은, 저장조에 담긴 고온의 케미컬(Chemical)을 사용하여 웨이퍼 상에 형성된 폴리실리콘막, 산화막, 질화막 등을 제거하는 공정이며, 세정공정 또한 저장조에 담긴 특정 케미컬을 사용하여 웨이퍼 표면에 부착된 폴리머(Polymer), 파티클(Particle), 중금속 등과 같은 오염물질을 제거하는 공정으로써, 이러한 공정들은 모두 습식식각장치에서 이루어지게 된다.The wet etching process is a process of removing a polysilicon film, an oxide film, or a nitride film formed on a wafer by using a high temperature chemical contained in a storage tank, and the cleaning process is also attached to the wafer surface using a specific chemical contained in the storage tank. The process removes contaminants such as polymers, particles, heavy metals, etc., all of which are performed in a wet etching apparatus.
도1은 케미컬이 순환공급되는 종래의 반도체 제조용 습식식각장치를 설명하기 위한 도면이다.1 is a view for explaining a conventional wet etching apparatus for manufacturing a semiconductor is supplied with the circulation.
도1을 참조하면, 일정량 이상이 되면 오우버플로우(Over flow)되는 플루오르화수소(HF) 등의 케미컬이 담기고, 상면이 개방된 내부저장조(14)가 설치되어 있다. 상기 내부저장조(14) 내부에는 웨이퍼(12)가 적재된 캐리어(Carrier : 10) 2 개가 서로 이격거리를 가지며 위치하여 있고, 캐리어(10) 사이의 이격공간 즉 내부저장조(14) 저면 중앙부에는 케미컬 공급구(24)가 형성되어 있다.Referring to FIG. 1, when a predetermined amount or more is contained, an internal storage tank 14 containing a chemical such as hydrogen fluoride (HF) that is overflowed and having an open upper surface is installed. In the internal reservoir 14, two carriers 10 on which the wafers 12 are loaded are positioned at a distance from each other, and a space is formed between the carriers 10, that is, in the center of the bottom surface of the internal reservoir 14. The supply port 24 is formed.
또한, 내부저장조(14) 외부에는 내부저장조(14)에서 오우버플로우된 케미컬을 수용하도록 내부저장조(14)를 포함하고, 상면이 개방된 외부저장조(16)가 설치되어 있다. 상기 외부저장조(16) 일측 저면에는 케미컬 방출구(18)가 형성되어 있다.In addition, the external storage tank 14 is provided with an external storage tank 16 including an internal storage tank 14 to accommodate the overflowed chemicals in the internal storage tank 14 and having an open top surface. A chemical discharge port 18 is formed at one bottom of the external storage tank 16.
또한, 상기 케미컬 방출구(18)와 펌프(20)가 배관라인으로 연결되고, 펌프(20)와 필터(22)가 배관라인으로 연결되어 있다.In addition, the chemical discharge port 18 and the pump 20 is connected to the pipe line, the pump 20 and the filter 22 is connected to the pipe line.
그리고, 필터(22)와 내부저장조(14) 저면 중앙부에 형성된 케미컬 공급구(24)가 연결되어 있다.The filter 22 and the chemical supply port 24 formed at the center of the bottom surface of the internal reservoir 14 are connected to each other.
따라서, 웨이퍼(12)를 적재한 2 개의 캐리어(10)가 일정량의 케미컬이 담긴 내부저장조(14)에 위치하여 식각공정이 진행된다.Therefore, the two carriers 10 on which the wafers 12 are loaded are located in the internal storage tank 14 containing a predetermined amount of chemical, and the etching process is performed.
이때, 내부저장조(14)에 담긴 케미컬은 일정량 이상이 되면 외부저장조(16)로 오우버플로우되어 외부저장조(16) 저면에 형성된 케미컬 방출구(18)를 통해서 펌프(20)로 공급된다.At this time, the chemical contained in the internal storage tank 14 is overflowed to the external storage tank 16 when a predetermined amount or more is supplied to the pump 20 through the chemical discharge port 18 formed on the bottom of the external storage tank 16.
펌프(20)로 공급된 케미컬은, 펌프(20)의 펌핑동작에 의해서 높은 압력으로 필터(22)를 통과하며 케미컬에 포함된 이물질이 제거되는 필터링공정이 진행된다.The chemical supplied to the pump 20 passes through the filter 22 at a high pressure by a pumping operation of the pump 20 and a filtering process is performed in which foreign substances contained in the chemical are removed.
이어서, 필터(22)를 통과한 케미컬은 내부저장조(14) 저면 중앙부에 형성된 케미컬 공급구(24)를 통해서 내부저장조(14)로 공급되어 내부저장조(14)에 담긴 케미컬을 유동시켜 웨이퍼(12) 식각공정이 원할히 진행될 수 있도록 한다.Subsequently, the chemical having passed through the filter 22 is supplied to the internal storage tank 14 through the chemical supply port 24 formed at the center of the bottom surface of the internal storage tank 14 to flow the chemical contained in the internal storage tank 14 to the wafer 12. ) Allow the etching process to proceed smoothly.
그러나, 케미컬 공급구(24)가 내부저장조(14) 저면 중앙에 하나 형성되어 있으므로 인해서 케미컬 공급구(24)와 멀리 떨어져 펌프(20)의 펌핑력이 전달되지 않는 내부저장조(14) 양측 내벽과 캐리어(10) 사이의 공간에서 케미컬이 회전하는 와류현상이 발생하여 웨이퍼(12)의 식각불량이 발생하는 문제점이 있었다.However, since the chemical supply port 24 is formed at the center of the bottom surface of the internal reservoir 14, the inner walls of both sides of the internal reservoir 14 are not separated from the chemical supply port 24 so that the pumping force of the pump 20 is not transmitted. In the space between the carriers 10, the vortex phenomenon in which the chemical rotates occurs, thereby causing a problem in that the etching of the wafer 12 occurs.
만일, 내부저장조(14) 내부에서 케미컬을 이용한 세정공정이 진행되었다면, 세정불량이 발생한다.If the cleaning process using the chemical is carried out inside the internal storage tank 14, poor cleaning occurs.
본 발명의 목적은, 케미컬 저장조 내부에서 와류현상이 발생하는 것을 방지하여 웨이퍼를 균일하게 식각 및 세정할 수 있는 반도체 제조용 습식식각장치를 제공하는 데 있다.SUMMARY OF THE INVENTION An object of the present invention is to provide a wet etching apparatus for manufacturing a semiconductor, which is capable of uniformly etching and cleaning a wafer by preventing eddy currents from occurring in a chemical reservoir.
도1은 종래의 반도체 제조용 습식식각장치를 설명하기 위한 개략적인 도면이다.1 is a schematic view for explaining a conventional wet etching apparatus for manufacturing a semiconductor.
도2는 본 발명에 따른 반도체 제조용 습식식각장치의 일 실시예를 설명하기 위한 도면이다.2 is a view for explaining an embodiment of a wet etching apparatus for manufacturing a semiconductor according to the present invention.
※도면의 주요부분에 대한 부호의 설명※ Explanation of symbols for main parts of drawing
10, 30 : 캐리어 12, 32 : 웨이퍼10, 30: carrier 12, 32: wafer
14, 34 : 내부저장조 16, 36 : 외부저장조14, 34: internal storage tank 16, 36: external storage tank
18, 38 : 케미컬 방출구 20, 40 : 펌프18, 38: chemical outlet 20, 40: pump
22, 42 : 필터 24, 44 : 케미컬 공급구22, 42: filter 24, 44: chemical supply port
46 : 받침대 48 : 분산판46: pedestal 48: dispersion plate
상기 목적을 달성하기 위한 본 발명에 따른 반도체 제조용 습식식각장치는, 웨이퍼가 적재된 복수의 캐리어가 투입되고 일정량의 케미컬이 담길 수 있는 내부저장조와, 상기 내부저장조를 포함하고 상기 내부저장조에서 오우버플로우되는 상기 케미컬이 저장되는 외부저장조와, 상기 외부저장조의 저면에 형성된 케미컬 방출구와 상기 내부저장조의 저면에 형성된 케미컬 공급구를 연결하며 중간에 펌프가 개재된 순환라인을 구비하는 반도체 제조용 습식식각장치에 있어서, 상기 케미컬 공급구는 상기 내부저장조의 저면에 복수개 형성됨을 특징으로 한다.The wet etching apparatus for manufacturing a semiconductor according to the present invention for achieving the above object includes an internal storage tank into which a plurality of carriers loaded with wafers can be put and a predetermined amount of chemical is contained therein, and the internal storage tank and the over-over from the internal storage tank. A wet etching apparatus for manufacturing a semiconductor having a circulation line connected with an external storage tank in which the flowed chemical is stored, a chemical discharge port formed in the bottom of the external storage tank, and a chemical supply port formed in the bottom of the internal storage tank, and having a pump interposed therebetween. In the, the chemical supply port is characterized in that a plurality formed on the bottom of the inner reservoir.
상기 케미컬 공급구는 상기 내부저장조에 투입되는 복수의 상기 캐리어와 동일한 수로 형성할 수 있다.The chemical supply port may be formed in the same number as the plurality of carriers to be introduced into the internal storage tank.
또한, 상기 케미컬 공급구는 상기 내부저장조에 투입되는 상기 캐리어 중앙부에 해당하는 상기 내부저장조 저면에 각각 형성되어 캐리어에 적재된 웨이퍼 상에 케미컬이 충분히 공급될 수 있도록 함이 바람직하다.In addition, the chemical supply port is preferably formed on the bottom surface of the internal storage tank corresponding to the center portion of the carrier to be introduced into the internal storage tank so that the chemical can be sufficiently supplied onto the wafer loaded on the carrier.
또한, 상기 케미컬 공급구 상부에는 상기 내부저장조 저면과 이격되고, 복수의 받침대가 구비된 분산판이 설치됨이 바람직하다.In addition, the upper portion of the chemical supply port is spaced apart from the bottom of the internal storage tank, it is preferable that the distribution plate provided with a plurality of pedestal is installed.
그리고, 상기 케미컬 공급구 상부에는 복수의 방출구멍이 형성된 노즐이 설치될 수도 있다.In addition, a nozzle having a plurality of discharge holes may be installed above the chemical supply port.
이하, 본 발명의 구체적인 실시예를 첨부한 도면을 참조하여 상세히 설명한다.Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.
도2는 케미컬이 순환공급되는 본 발명에 따른 반도체 제조용 습식식각장치의 일 실시예를 설명하기 위한 도면이다.2 is a view for explaining an embodiment of a wet etching apparatus for manufacturing a semiconductor according to the present invention in which chemical is circulated and supplied.
도2를 참조하면, 내부에 특정 반도체소자 제조공정이 진행된 웨이퍼(32)가 적재된 2개의 캐리어(30)가 위치하고, 일정량 이상이 되면 오우버플로우되는 케미컬이 담기고, 상면이 개방된 내부저장조(34)가 설치되어 있다.Referring to FIG. 2, two carriers 30 in which a wafer 32 on which a specific semiconductor device manufacturing process is performed are loaded are placed, and when a predetermined amount or more is contained, an overflowing chemical is contained and the upper surface is opened. 34 is provided.
또한, 상기 내부저장조(34)에 투입된 캐리어(30)의 중앙부에 해당하는 내부저장조(34) 저면에 2개의 케미컬 공급구(38)가 형성되어 있다.In addition, two chemical supply holes 38 are formed on the bottom surface of the internal storage tank 34 corresponding to the center of the carrier 30 introduced into the internal storage tank 34.
상기 케미컬 공급구(38) 상부에는, 케미컬 공급구(38)를 통해서 공급되는 케미컬이 부딛히며 사방으로 분산될 수 있도록 복수의 받침대(46)에 의해서 지지되어 내부저장조(34) 저면과 일정거리 이격된 분산판(48)이 설치되어 있다.The upper portion of the chemical supply port 38 is supported by a plurality of pedestals 46 so that the chemicals supplied through the chemical supply port 38 are scattered in all directions and spaced apart from the bottom of the internal storage tank 34 by a predetermined distance. Distributed plate 48 is provided.
또한, 내부저장조(34) 외부에는 내부저장조(34)에서 오우버플로우된 케미컬을 수용하도록 내부저장조(34)를 포함하고, 상면이 개방된 외부저장조(36)가 설치되어 있다. 상기 외부저장조(36) 일측 저면에는 케미컬 방출구(38)가 형성되어 있다.In addition, an external storage tank 34 is provided on the outside of the internal storage tank 34 to include an internal storage tank 34 so as to accommodate an overflowed chemical in the internal storage tank 34. A chemical discharge port 38 is formed at one bottom of the external storage tank 36.
또한, 상기 케미컬 방출구(38)와 펌프(40)가 배관라인으로 연결되고, 펌프(40)와 필터(42)가 배관라인으로 연결되어 있다.In addition, the chemical discharge port 38 and the pump 40 is connected to the pipe line, the pump 40 and the filter 42 is connected to the pipe line.
그리고, 필터(42)와 내부저장조(34) 저면에 형성된 2개의 케미컬 공급구(44)가 2개의 분기라인이 형성된 배관라인으로 각각 연결되어 있다.In addition, the two chemical supply ports 44 formed on the bottom surface of the filter 42 and the internal storage tank 34 are connected to pipe lines each having two branch lines.
따라서, 특정 반도체소자 제조공정이 진행된 웨이퍼(32)를 적재한 캐리어(30)가 내부저장조(34)에 투입되어 식각공정이 진행된다.Therefore, the carrier 30 carrying the wafer 32 on which the specific semiconductor device manufacturing process is performed is introduced into the internal storage tank 34, and the etching process is performed.
이때, 내부저장조(34)에 담긴 케미컬은 일정량 이상이 되면 외부저장조(36)로 오우버플로우되어 외부저장조(36) 일측 저면에 형성된 케미컬 방출구(38)를 통해서 펌프(40)로 공급된다.At this time, the chemical contained in the internal storage tank 34 is overflowed to the external storage tank 36 when a predetermined amount or more is supplied to the pump 40 through the chemical discharge port 38 formed on the bottom surface of one side of the external storage tank 36.
펌프(40)로 공급된 케미컬은 펌프(40)의 펌핑에 의해서 높은 압력으로 필터(42)를 통과하여 케미컬에 포함된 이물질이 제거되는 필터링공정이 진행된다.The chemical supplied to the pump 40 passes through the filter 42 at a high pressure by the pumping of the pump 40 to remove the foreign matter contained in the chemical.
필터링공정이 진행된 일정량의 케미컬은 2개의 분기라인을 통과하고, 2개의 케미컬 공급구(44)를 통해서 내부저장조(34)로 각각 공급된다.A certain amount of chemical that has undergone the filtering process passes through two branching lines, and is supplied to the internal storage 34 through two chemical supply ports 44, respectively.
내부저장조(34)에 공급된 케미컬은, 분산판(48)과 부딛힌 후, 복수의 받침대(46)와 받침대(46) 사이의 이격공간을 통해서 캐리어(30)에 적재된 웨이퍼(32) 상에 공급된다.The chemical supplied to the internal storage tank 34, after colliding with the dispersion plate 48, is placed on the wafer 32 loaded on the carrier 30 through a space between the plurality of pedestals 46 and 46. Supplied to.
또한, 제작자의 의도에 따라서, 상기 케미컬 공급구(44) 상부에 복수의 방출구멍이 형성된 노즐을 설치할 수도 있다.In addition, according to the intention of the manufacturer, a nozzle having a plurality of discharge holes may be provided in the upper portion of the chemical supply port (44).
따라서, 본 발명에 의하면 내부저장조에 투입되는 캐리어의 중앙부에 해당하는 내부저장조 저면에 복수의 케미컬 공급구가 형성되고, 상기 케미컬 공급구 상부에 케미컬이 분산될 수 있도록 하는 분산판이 형성됨으로 인해서 캐리어에 적재된 웨이퍼 상에 케미컬이 균일하게 공급된다.Therefore, according to the present invention, a plurality of chemical supply ports are formed on the bottom of the internal storage tank corresponding to the central portion of the carrier to be inserted into the internal storage tank, and a dispersion plate is formed on the chemical supply port so that the chemicals can be dispersed. The chemical is uniformly supplied on the loaded wafer.
그러므로, 내부저장조 내부에서 케미컬이 회전하는 와류현상이 발생하는 것이 방지되어 식각공정 또는 세정공정이 원활히 진행되는 효과가 있다.Therefore, the vortex phenomenon in which the chemical rotates is prevented from occurring in the internal storage tank, so that the etching process or the cleaning process proceeds smoothly.
이상에서 본 발명은 기재된 구체예에 대해서만 상세히 설명되었지만 본 발명의 기술사상 범위 내에서 다양한 변형 및 수정이 가능함은 당업자에게 있어서 명백한 것이며, 이러한 변형 및 수정이 첨부된 특허청구범위에 속함은 당연한 것이다.Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.
Claims (7)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019960056738A KR19980037916A (en) | 1996-11-22 | 1996-11-22 | Wet etching equipment for semiconductor manufacturing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019960056738A KR19980037916A (en) | 1996-11-22 | 1996-11-22 | Wet etching equipment for semiconductor manufacturing |
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| Publication Number | Publication Date |
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| KR19980037916A true KR19980037916A (en) | 1998-08-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| KR1019960056738A Ceased KR19980037916A (en) | 1996-11-22 | 1996-11-22 | Wet etching equipment for semiconductor manufacturing |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119132917A (en) * | 2024-08-26 | 2024-12-13 | 重庆欣晖材料技术有限公司 | Etching device and electrode |
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1996
- 1996-11-22 KR KR1019960056738A patent/KR19980037916A/en not_active Ceased
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119132917A (en) * | 2024-08-26 | 2024-12-13 | 重庆欣晖材料技术有限公司 | Etching device and electrode |
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