GB2330003A - Thermal processing apparatus - Google Patents
Thermal processing apparatus Download PDFInfo
- Publication number
- GB2330003A GB2330003A GB9820636A GB9820636A GB2330003A GB 2330003 A GB2330003 A GB 2330003A GB 9820636 A GB9820636 A GB 9820636A GB 9820636 A GB9820636 A GB 9820636A GB 2330003 A GB2330003 A GB 2330003A
- Authority
- GB
- United Kingdom
- Prior art keywords
- heat transfer
- peltier elements
- electric heater
- heat
- transfer plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/67005—Apparatus not specifically provided for elsewhere
- H01L21/67011—Apparatus for manufacture or treatment
- H01L21/67098—Apparatus for thermal treatment
- H01L21/67103—Apparatus for thermal treatment mainly by conduction
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B21/00—Machines, plants or systems, using electric or magnetic effects
- F25B21/02—Machines, plants or systems, using electric or magnetic effects using Peltier effect; using Nernst-Ettinghausen effect
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Resistance Heating (AREA)
- Cooling Or The Like Of Electrical Apparatus (AREA)
- Control Of Temperature (AREA)
- Container, Conveyance, Adherence, Positioning, Of Wafer (AREA)
- Furnace Details (AREA)
- Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
Abstract
Thermal processing apparatus for a sheet-like workpiece W such as a semiconductor wafer, optical disc or liquid crystal substrate, comprises a heat transfer plate 2 under which an electric heater 3 is installed to heat the heat transfer plate evenly. Peltier elements 5 are additionally provided under the electric heater, and may be used to raise or lower the temperature of the workpiece, there being a cooling section 6 through which cooling liquid flows. There may be an intermediate plate 4 to diffuse heat from the Peltier elements 5. A controller 9 controls the ac power to the electric heater 3 and dc direction and power to the Peltier elements 5 in dependence on the output of a temperature sensor 8.
Description
THERMAL PROCESSING APPARATUS FOR SHEET-LIKE WORKPIECES
The present invention relates to a thermal processing apparatus for sheet-like workpieces such as semiconductor wafers, or optical disc or liquid crystal substrates.
Japanese Patent Application No. 9-140492 describes a thermal processing apparatus for sheet-like workpieces that employs Peltier elements.
As shown in FIG. 4, the known thermal processing apparatus comprises multiple supplementary heating Peltier elements 22; a main heating means 23 which has a built-in electric heater, and a cooling means 25 located via heatexchanging Peltier elements 24 installed under a heat transfer plate 21.
A workpiece W is placed on the heat transfer plate 21 with a small gap therebetween. Heat from the main heating means 23 is transmitted to the heat transfer plate 21 via the Peltier elements 22, and radiant heat from the upper surface of the heat transfer plate 21 is used to heat the workpiece W to a predetermined temperature.
To cool the workpiece W, heat from the heat transfer plate 21 is transferred from the Peltier elements 22 to the cooling means 25 via the main heating means 23 and heat-exchanging Peltier elements 24.
Thermal treatment apparatuses using Peltier elements have the advantage of providing excellent processing efficiency as a result of prompt heat transferral during heating and cooling. If, however, the multiple Peltier elements are assembled on the heat transfer plate 21, then due to restrictions imposed by the shape and size of the Peltier elements 22 and practical problems, it is difficult to install the Peltier elements without leaving gaps between them. As a result of such gaps, the temperature distribution of the heat transfer plate 21 cannot be made completely uniformly, due to the likelihood of a slight difference in temperature between those portions which are adjacent the Peltier elements 22 and those which are not. In normal heating, such a difference in temperature does not create a significant problem. In the case of workpieces for which precise heating is required, however, it is desirable that the difference in temperature be eliminated in order to make the temperature distribution as uniform as possible.
It is an object of this invention to provide a thermal processing apparatus having a high heating accuracy, which can reliably homogenize the temperature distribution of a heat transfer plate used for the thermal processing of workpieces by a simple mechanism.
It is another object of this invention to enable the temperature of the heat transfer plate of a thermal processing apparatus to be increased and decreased promptly in order to improve the efficiency of heating and cooling workpieces.
To achieve these objects, this invention provides a thermal processing apparatus comprising multiple Peltier elements and a cooling section assembled via an electric heater under a heat transfer plate, the top surface of which is a heat transfer surface that transfers heat to workpieces. The electric heater is installed in such away as to evenly heat the heat transfer surface of the heat transfer plate.
In a thermal processing apparatus of this configuration, when the electric heater is interposed between the multiple Peltier elements and the heat transfer plate, the Peltier elements and the electric heater are used to heat the heat transfer plate. Thus, the electric heater can be used to correct the difference in temperature between those portions of the heat transfer plate adjacent which the Peltier elements are present and those from which the Peltier elements are absent, thereby approximately homogenizing the temperature distribution of the heat transfer surface of the heat transfer plate. Furthermore, the amount of power supplied to the Peltier elements can be increased and reduced in order to simply adjust the temperature of the heat transfer plate. Consequently, the temperature of the heat transfer plate can be set and adjusted easily.
In addition, to cool workpieces, the electric heater is turned off and a reverse direct current is allowed to flow through the Peltier elements to use the heat-transfer-plate side of the Peltier elements as the cooled side. Heat from the heat transfer plate is transferred to the cooling section through the Peltier elements in order to reduce the temperature of the heat transfer plate promptly.
Thus, if the temperature of the workpieces is higher than the set temperature of the heat transfer plate or if the heat transfer plate is to be used to cool the workpiece, the power to the electric heater is turned off and the current through the multiple Peltier elements is reversed to cool the heat transfer plate by means of the
Peltier elements. As a result, the temperature of the heat transfer plate can be reduced promptly.
In addition, since the heat in the heated side of the
Peltier elements is released, the cooling efficiency of the
Peltier elements increases.
According to one embodiment, the electric heater is manufactured in the form of a sheet by enclosing a heating element in a casing that resists and transfers heat and that provides electric insulation, and the heater is of a size corresponding to the overall heat transfer surface of the heat transfer plate.
According to another embodiment, an intermediate plate consisting of a material that transfers heat is installed between the electric heater and the Peltier elements in such a way as to cover the entire electric heater. The intermediate plate acts as both a means for pressing and holding the electric heater and a means for diffusing heat from the multiple
Peltier elements in order to transfer it uniformly to the entire heat transfer plate. The intermediate plate enables the temperature distribution of the heat transfer plate to be more reliably homogenized.
Furthermore, multiple Peltier elements may be stacked one atop the other.
According to a specific embodiment, the thermal processing apparatus comprises a temperature sensor for detecting the temperature of the heat transfer plate and outputting a signal; and a controller that controls the power to the electric heater and the Peltier elements in response to the output signal from the temperature sensor.
The invention will now be further described by way of example with reference to the accompanying drawings in which
FIG. 1 is a sectional view showing one embodiment of a thermal processing apparatus according to this invention.
FIG. 2 is a rear view showing an electric heater mounted on a heat transfer plate.
FIG. 3 is a top view showing an arrangement of Peltier elements.
FIG. 4 is a sectional view of a proposed thermal processing apparatus.
FIG. 1 shows a representative embodiment of a thermal processing apparatus according to this invention. A thermal processing apparatus 1 has a heat transfer plate 2 the top surface of which is a heat transfer surface 2a along which heat is transferred to a sheet-like workpiece W; an electric heater 3 installed under the heat transfer plate 2 to evenly heat the overall heat transfer surface 2a; an intermediate plate 4 provided under the electric heater 3; multiple Peltier elements 5 installed adjacent to one another in such a way as to heat the heat transfer plate 2 via the intermediate plate 4 and electric heater 3; and a cooling section 6 installed under the Peltier elements 5.
A workpiece W is placed on the heat transfer plate 2, which heats and/or cools it to a predetermined temperature.
The heat transfer plate is formed as a disk having a larger diameter (for example, 200 to 320 mm) than the workpiece W, and an annular edge 2b is formed on the outer circumference of the bottom surface of the plate 2 in such away as to surround the electric heater 3 as shown in FIG. 2. The inner diameter of the edge 2b is slightly larger than the outer diameter of the workpiece W.
The electric heater 3 is formed as a thin sheet having a size corresponding to the overall heat transfer surface 2a of the heat transfer plate 2, by enclosing a heating element in a casing that resists and transfers heat and that provides electric insulation. The heating element is formed by cutting a thin foil material, which generates heat due to electric resistance, into a predetermined pattern or folding a linear material into a predetermined pattern. The casing is formed of silicone rubber.
In addition, the intermediate plate 4 acts as both a means for holding the electric heater 3 and a means for diffusing heat from the multiple Peltier elements 5 to transfer it uniformly to the entire heat transfer plate 2.
The intermediate plate is preferably formed of a material such as aluminum or copper that transfers heat appropriately and is installed in such a way as to cover the entire electric heater 3. The intermediate plate 4 preferably has a thickness of, for example, 5 mm.
The Peltier elements 5 are arranged radially around the center of the heat transfer plate 2 at equal angles and equal intervals as shown in FIG. 3. In addition, the
Peltier elements 5 are preferably installed in such a way that two elements are stacked as shown in the figure in order to maintain a difference in temperature between the two vertical surfaces.
The cooling section 6 includes a cooling channel 6a through which a cooling liquid flows and which is connected to a cooling water source.
The thermal processing apparatus 1 also includes a temperature sensor 8 that detects the temperature of the heat transfer plate 2 in order to output a signal; and a controller 9. The controller 9 controls the amount of power supplied to the electric heater 3 and each Peltier element 5 in response to the output signal from the temperature sensor 8 in order to adjust the temperature of the heat transfer plate 2. An alternating current is supplied to the electric heater 3, and a direct current is supplied to the Peltier elements 5. The direct current supplied to the Peltier elements 5 can be reversed.
The heat transfer plate 2 has three equilateraltriangular spacers 10 that support the thermally processed workpiece W with a slight gap between the plate 2 and the heat transfer surface 2a and that each have a spherical tip.
An appropriate elevating means (not shown) can be used to elevate these spacers 10 from the illustrated positions to the respective positions at which they protrude.
These spacers 10 allow a slight gap to be maintained between the top surface of the heat transfer plate 2 and the workpiece W. Although the amount of heat transmitted to the workpiece W slightly decreases as result, this gap enables the workpiece W to be heated and cooled more uniformly.
In the thermal processing apparatus of this configuration, to heat the workpiece W, a direct current is allowed to flow through the Peltier elements 5 in a direction such that the heat transfer plate 2 is the heated side, while an alternating current is allowed to flow through the electric heater 3. Thus, the heat transfer plate 2 is heated by the electric heater 3 and the Peltier elements 5 in order to uniformly heat the workpiece W on the heat transfer surface 2a. In this case, a cooling liquid is allowed to flow through the cooling channel 6a in the cooling section 6.
In response to a signal output from the temperature sensor 8, the temperature of the heat transfer plate 2 is precisely controlled by adjusting the amount of power supplied to the electric heater 3 and the Peltier elements 5 by means of the controller 9.
Thus, the electric heater 3 is installed closer to the heat transfer plate 2 than the Peltier elements 5, and the
Peltier elements 5 are provided outside the electric heater 3. Therefore, the electric heater 3 directly heats the heat transfer plate 2 to prevent the temperature of the heat transfer plate 2 from varying between those portions in which the Peltier elements 5 are present and those from which the elements 5 are absent, thereby enabling the temperature distribution of the overall heat transfer surface 2a of the heat transfer plate 2 to be reliably homogenized. Moreover, the heat from the multiple Peltier elements 5 is diffused by the intermediate plate 4 and transmitted to the entire heat transfer plate 2, thereby further facilitating the homogenization of the temperature distribution of the heat transfer plate 2.
In addition, the amount of power supplied to the
Peltier elements 5 can be increased and reduced in order to simply adjust the temperature of the heat transfer plate 2.
Consequently, the temperature of the heat transfer plate 2 can be set and adjusted easily.
To reduce the temperature of the workpiece W, a reverse current can be allowed to flow through the Peltier elements 5. This means that the heat-transfer-plate (2) side of the Peltier elements 5 is the cooled side. The temperature of the heat transfer plate 2 can therefore be reduced.
In addition, to cool the heated workpiece W, the electric heater 3 is turned off and a reverse direct current is allowed to flow through the Peltier elements 5 as described above. Thus, the heat-transfer-plate (2) side of the Peltier elements 5 is used as the cooled side to transfer the heat from the heat transfer plate 2 through the
Peltier elements 5 in order to reduce the temperature of the heat transfer plate 2 promptly.
If the temperature of the workpiece W is higher than the set temperature of the heat transfer plate 2 or if the heat transfer plate 2 is used to cool the workpiece W, the power to the electric heater 3 is turned off and the current is allowed to flow in reverse through the multiple Peltier elements 5.
In addition, since the heat in the heated side of the
Peltier elements 5 is released by the cooling section 6, the cooling efficiency of the Peltier elements 5 increases.
Claims (6)
- CLAIMS 1. A thermal processing apparatus comprising a heat transfer plate, at least part of the top surface of which is a heat transfer surface from which heat is transferred to a sheet-like workpiece, an electric heater installed under the heat transfer plate to evenly heat the heat transfer surface, multiple Peltier elements installed adjacent to one another in such a way as to heat the heat transfer plate via the electric heater, and a cooling section installed under the heater.
- 2. A thermal processing apparatus as claimed in Claim 1 wherein the electric heater is in the form of a sheet of a size corresponding to that of the heat transfer surface of the heat transfer plate, the heater comprising a heating element enclosed in a casing of heat conductive and electrically insulative material.
- 3. A thermal processing apparatus as claimed in either Claim 1 or Claim 2 wherein an intermediate plate of a heat transfer material is installed between the electric heater and the Peltier elements, the intermediate plate covering the entire electric heater, the intermediate plate acting as both a means for holding the electric heater and a means for diffusing heat from the multiple Peltier elements to transfer it uniformly to the heat transfer plate.
- 4. A thermal processing apparatusas claimed in any preceding Claim wherein the multiple Peltier elements are arranged in stacks.
- 5. A thermal processing apparatus as claimed in any preceding Claim further comprising a temperature sensor for detecting the temperature of the heat transfer plate and outputting a signal, and a controller that controls the power to the electric heater and the Peltier elements in response to the output signal from the temperature sensor
- 6. A thermal processing apparatus substantially as hereinbefore described and illustrated in the accompanying drawings.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9282783A JP2954908B2 (en) | 1997-09-30 | 1997-09-30 | Substrate temperature controller |
Publications (3)
Publication Number | Publication Date |
---|---|
GB9820636D0 GB9820636D0 (en) | 1998-11-18 |
GB2330003A true GB2330003A (en) | 1999-04-07 |
GB2330003B GB2330003B (en) | 1999-10-27 |
Family
ID=17657032
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB9820636A Expired - Fee Related GB2330003B (en) | 1997-09-30 | 1998-09-22 | Thermal processing apparatus for sheet-like workpieces |
Country Status (5)
Country | Link |
---|---|
JP (1) | JP2954908B2 (en) |
KR (1) | KR100303167B1 (en) |
CN (1) | CN1106046C (en) |
GB (1) | GB2330003B (en) |
TW (1) | TW429480B (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2792084A1 (en) * | 1999-04-12 | 2000-10-13 | Joint Industrial Processors For Electronics | INTEGRATED HEATING AND COOLING DEVICE IN A HEAT TREATMENT REACTOR OF A SUBSTRATE |
US7155915B2 (en) * | 2003-12-26 | 2007-01-02 | Samsung Electronics, Co., Ltd. | Temperature controller for a semiconductor-fabricating tool |
US7247819B2 (en) | 2004-06-28 | 2007-07-24 | Ngk Insulators, Ltd. | Substrate heating apparatus |
US7804291B2 (en) * | 2004-09-28 | 2010-09-28 | Agere Systems Inc. | Semiconductor test device with heating circuit |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005074450A2 (en) | 2004-01-30 | 2005-08-18 | Tokyo Electron Limited | Substrate holder having a fluid gap and method of fabricating the substrate holder |
US8461674B2 (en) * | 2011-09-21 | 2013-06-11 | Lam Research Corporation | Thermal plate with planar thermal zones for semiconductor processing |
DE102013223430A1 (en) * | 2013-11-18 | 2015-05-21 | BSH Hausgeräte GmbH | Device with a power electronics module for supplying an electrical load of a household appliance with electrical supply voltage, household appliance and method for producing such a device |
CN108195722A (en) * | 2017-11-21 | 2018-06-22 | 国家电网公司 | Thermostat based on the detection of insulating oil interfacial tension |
CN108486649B (en) * | 2018-03-13 | 2019-11-08 | 广州铁路职业技术学院(广州铁路机械学校) | Silicon wafer casting method and device |
CN113412031A (en) * | 2021-06-21 | 2021-09-17 | 合肥联宝信息技术有限公司 | Heating module and electronic equipment |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2261111A (en) * | 1991-09-26 | 1993-05-05 | Stuart Scient Company Limited | Apparatus and method for heating and/or cooling reaction vessels |
JPH09306978A (en) * | 1996-05-15 | 1997-11-28 | Dainippon Screen Mfg Co Ltd | Temp. control of substrate, substrate heat treating apparatus and substrate supporting apparatus |
WO1998005060A1 (en) * | 1996-07-31 | 1998-02-05 | The Board Of Trustees Of The Leland Stanford Junior University | Multizone bake/chill thermal cycling module |
GB2326278A (en) * | 1997-06-10 | 1998-12-16 | Smc Corp | Thin plate cooling device |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS579925A (en) * | 1980-06-19 | 1982-01-19 | Takenaka Komuten Co Ltd | Foundation structure for building |
EP0288022B1 (en) * | 1987-04-22 | 1995-11-15 | Sharp Kabushiki Kaisha | Superconductive apparatus |
-
1997
- 1997-09-30 JP JP9282783A patent/JP2954908B2/en not_active Expired - Fee Related
-
1998
- 1998-09-07 TW TW087114830A patent/TW429480B/en not_active IP Right Cessation
- 1998-09-22 GB GB9820636A patent/GB2330003B/en not_active Expired - Fee Related
- 1998-09-29 KR KR1019980040596A patent/KR100303167B1/en not_active IP Right Cessation
- 1998-09-30 CN CN98120856A patent/CN1106046C/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2261111A (en) * | 1991-09-26 | 1993-05-05 | Stuart Scient Company Limited | Apparatus and method for heating and/or cooling reaction vessels |
JPH09306978A (en) * | 1996-05-15 | 1997-11-28 | Dainippon Screen Mfg Co Ltd | Temp. control of substrate, substrate heat treating apparatus and substrate supporting apparatus |
WO1998005060A1 (en) * | 1996-07-31 | 1998-02-05 | The Board Of Trustees Of The Leland Stanford Junior University | Multizone bake/chill thermal cycling module |
GB2326278A (en) * | 1997-06-10 | 1998-12-16 | Smc Corp | Thin plate cooling device |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2792084A1 (en) * | 1999-04-12 | 2000-10-13 | Joint Industrial Processors For Electronics | INTEGRATED HEATING AND COOLING DEVICE IN A HEAT TREATMENT REACTOR OF A SUBSTRATE |
WO2000062333A1 (en) * | 1999-04-12 | 2000-10-19 | Joint Industrial Processors For Electronics | Integrated heating and cooling device in a reactor for thermal treatment of a substrate |
US7155915B2 (en) * | 2003-12-26 | 2007-01-02 | Samsung Electronics, Co., Ltd. | Temperature controller for a semiconductor-fabricating tool |
US7247819B2 (en) | 2004-06-28 | 2007-07-24 | Ngk Insulators, Ltd. | Substrate heating apparatus |
US7804291B2 (en) * | 2004-09-28 | 2010-09-28 | Agere Systems Inc. | Semiconductor test device with heating circuit |
Also Published As
Publication number | Publication date |
---|---|
CN1106046C (en) | 2003-04-16 |
TW429480B (en) | 2001-04-11 |
JPH11110053A (en) | 1999-04-23 |
CN1213791A (en) | 1999-04-14 |
KR19990030250A (en) | 1999-04-26 |
JP2954908B2 (en) | 1999-09-27 |
GB9820636D0 (en) | 1998-11-18 |
GB2330003B (en) | 1999-10-27 |
KR100303167B1 (en) | 2001-11-22 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20020922 |