WO1991009148A1 - Appareil de traitement sous vide et procede de formation de pellicules utilisant ledit appareil - Google Patents

Appareil de traitement sous vide et procede de formation de pellicules utilisant ledit appareil Download PDF

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Publication number
WO1991009148A1
WO1991009148A1 PCT/JP1990/001601 JP9001601W WO9109148A1 WO 1991009148 A1 WO1991009148 A1 WO 1991009148A1 JP 9001601 W JP9001601 W JP 9001601W WO 9109148 A1 WO9109148 A1 WO 9109148A1
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WIPO (PCT)
Prior art keywords
substrate
temperature
stage
infrared radiation
radiation thermometer
Prior art date
Application number
PCT/JP1990/001601
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English (en)
Japanese (ja)
Inventor
Akira Okamoto
Shigeru Kobayashi
Hideaki Shimamura
Susumu Tsuzuku
Eisuke Nishitani
Satoshi Kishimoto
Yuji Yoneoka
Original Assignee
Hitachi, Ltd.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from JP2225388A external-priority patent/JP2923008B2/ja
Application filed by Hitachi, Ltd. filed Critical Hitachi, Ltd.
Priority to DE19904092221 priority Critical patent/DE4092221T1/de
Priority to DE4092221A priority patent/DE4092221C2/de
Priority to KR1019910700879A priority patent/KR940007608B1/ko
Publication of WO1991009148A1 publication Critical patent/WO1991009148A1/fr
Priority to US08/260,321 priority patent/US6171641B1/en

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    • 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
    • H01L21/67155—Apparatus for manufacturing or treating in a plurality of work-stations
    • H01L21/67161—Apparatus for manufacturing or treating in a plurality of work-stations characterized by the layout of the process chambers
    • H01L21/67173—Apparatus for manufacturing or treating in a plurality of work-stations characterized by the layout of the process chambers in-line arrangement
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/50—Substrate holders
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/54—Controlling or regulating the coating process
    • C23C14/541—Heating or cooling of the substrates
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/56—Apparatus specially adapted for continuous coating; Arrangements for maintaining the vacuum, e.g. vacuum locks
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/458—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for supporting substrates in the reaction chamber
    • C23C16/4582—Rigid and flat substrates, e.g. plates or discs
    • C23C16/4583—Rigid and flat substrates, e.g. plates or discs the substrate being supported substantially horizontally
    • C23C16/4586—Elements in the interior of the support, e.g. electrodes, heating or cooling devices
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/46—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for heating the substrate
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/46—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for heating the substrate
    • C23C16/463—Cooling of the substrate
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/46—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for heating the substrate
    • C23C16/463—Cooling of the substrate
    • C23C16/466—Cooling of the substrate using thermal contact gas
    • 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
    • H01L21/67109—Apparatus for thermal treatment mainly by convection
    • 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
    • H01L21/67242—Apparatus for monitoring, sorting or marking
    • H01L21/67248—Temperature monitoring
    • 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
    • H01L21/683—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 for supporting or gripping
    • H01L21/6838—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 for supporting or gripping with gripping and holding devices using a vacuum; Bernoulli devices

Definitions

  • the present invention relates to a vacuum processing apparatus for performing various types of processing on a substrate in a vacuum, a film forming apparatus and a film forming method using the same, and particularly to a vacuum processing apparatus suitable for use in a semiconductor device manufacturing process and The present invention relates to a film forming apparatus and a film forming method using the same.
  • a typical process equipment whose temperature is the most important setting condition is a so-called furnace body such as an oxidation furnace.
  • the inside of this type of furnace is an oxidizing atmosphere that replaces the atmosphere.
  • the replacement atmosphere is atmospheric pressure or higher, and the silicon wafer in the furnace body, for example, is heated by radiation from the heater installed around the quartz tube and heat conduction by the atmospheric pressure atmosphere in the quartz tube. To be done. That is, since there is a medium that conducts heat, the temperature can be measured relatively accurately by using a probe such as a thermocouple installed in the heat conducting atmosphere.
  • a photoresist baking device used in the step of applying a photoresist used as a mask in the etching step can be cited.
  • baking is performed in an atmospheric pressure atmosphere, Place the silicone on a heat block that has a larger heat capacity than the silicone heated to the specified baking temperature, and then place the silicone vacuum on the heat block side. Presses the entire silicone wafer against the heat block by atmospheric pressure. For this reason, the wafer temperature is balanced with the temperature of the heat block, so that the temperature of the wafer can be accurately controlled and managed by a temperature probe such as a thermocouple attached to the heat block. .
  • Many semiconductor manufacturing processes rely on highly pure materials and well-controlled reactions in a dust-free environment, and therefore often require processing in vacuum.
  • thermocouple It has been attempted to accurately measure the temperature of the uhha during the process by attaching the thermocouple to the woofer, but in order to measure the temperature of the uhah with the thermocouple in point contact with the uhah, the contact state of the It is difficult to stabilize the temperature constant, and there is a drawback that the measurement temperature is not reproducible. Also, when the wafer is heated by infrared radiation, the uhha is almost transparent in a wide range of the infrared region, so heat is not transferred only to the thermocouple by conduction from the wafer, but the thermocouple itself. The temperature of the wafer may be difficult to measure accurately because it may be heated by the lamp heater.
  • the wafer is heated by a small force as compared with the use of the vacuum chuck under the atmospheric pressure.
  • the temperature is not uniform and reproducible because it is clamped on the top block.
  • the biggest drawback is that heat transfer from the heat block to the uhha takes longer due to the lower density of the heat transfer medium. Even if the heat block and the woo reach the thermal equilibrium in the end, it takes several seconds to several tens of seconds as described in the above example, and the reproducibility of the maturing conduction time is further increased. It is thought that various factors have an impact on the above.
  • a method of measuring the radiation intensity from a wafer in the infrared region using an infrared thermometer has been proposed. That is, in this method, the wafer is placed on a heating stage in a sputtering apparatus and heated, while the infrared thermometer is used to heat the wafer through a through hole formed in a target installed facing the wafer. The temperature is measured. That is, the infrared emissivity of wafer at a specific temperature is measured in advance by the calibration sample, and the wafer temperature in the sputter is controlled by the measured value.
  • the same metal as the target material for example, a silicon wafer on which aluminum of several 100 A is deposited is used, but the side to be observed by the infrared thermometer of HUHA. Since the infrared emissivity from the wafer surface differs depending on the presence or absence of a metal film on the surface of the wafer, it is not possible to control the temperature before film formation.
  • the ideal method for controlling the temperature of the HUHA using an infrared thermometer is to calibrate the infrared thermometer using the wafer itself on which the film is actually formed, and to determine the difference in infrared emissivity depending on the presence or absence of the film and its state. It is a method that can be measured without being affected by. However, no one that can be put to practical use has been proposed yet.
  • an object of the present invention is to eliminate the above-mentioned conventional problems, and the first object thereof is to provide an improved vacuum processing apparatus capable of accurately measuring and controlling the temperature of a substrate in a vacuum.
  • the second purpose is to apply this vacuum processing apparatus, for example, a film forming apparatus such as a sputtering apparatus or a CVD (Chemical Vapor Depth Initiation) apparatus, and the third purpose is to A film forming method using an improved film forming apparatus, and a fourth purpose is It is to provide a method for measuring the substrate temperature.
  • a first infrared radiation thermometer for measuring radiant heat of a substrate on a temperature calibration stage which is provided with means for heating or cooling the substrate placed on the stage to a known set temperature;
  • the emissivity is calculated from the output of the infrared radiation thermometer based on the known temperature of the substrate, and the infrared ray sensitivity correction value for displaying the temperature of the substrate correctly by the first infrared radiation thermometer is calculated.
  • thermometer for measuring the radiation heat of the substrate on the stage in this vacuum processing chamber; and an infrared sensitivity correction value obtained from the output of the second infrared radiation thermometer at the temperature calibration stage.
  • thermometer equipped with means for heating or cooling the substrate placed on the stage to a known set temperature; the first infrared radiation temperature for measuring the radiant heat of the substrate on this temperature calibration stage The emissivity is obtained from the output of the first infrared radiation thermometer based on the known temperature of the substrate, and the temperature of the substrate is corrected by the first infrared radiation thermometer. Means for calculating the infrared sensitivity correction value for displaying the temperature; a stage on which the substrate exiting the temperature calibration stage is placed; a means for heating or cooling the substrate to a predetermined set temperature; and a vacuum for the substrate.
  • a vacuum processing chamber provided with a processing means; a second infrared radiation thermometer for measuring the radiant heat of the substrate on the stage in the vacuum processing chamber; and an output of the second infrared radiation thermometer.
  • Each of the above stages was provided with an observation hole for observing the temperature of the substrate by the infrared radiation thermometer, and the infrared light from the substrate was guided to the infrared radiation thermometer.
  • An optical path for the purpose which is in the plane of the stage in contact with the substrate, has a gas introducing means for filling the space formed by the substrate and the stage with a predetermined gas pressure and can close the observation hole.
  • the vacuum processing apparatus described in ⁇ or (2) above which is provided with a means for controlling the temperature of the base plate, which comprises a movable optical path closing shutter, (4)
  • a means for controlling the temperature of the base plate which comprises a movable optical path closing shutter, (4)
  • Each of the above stages has an observation hole for observing the temperature of the substrate by the infrared radiation thermometer, and an optical path for guiding infrared light from the substrate to the infrared thermometer. It has a gas introducing means for filling a predetermined gas with a predetermined gas pressure in the space formed by the base and the stage, which is in the plane of the stage in contact with the substrate.
  • Each of the above stages has a means for controlling the substrate temperature, which comprises a second window plate thinner than the thickness of the first window plate between the first window plate and the infrared thermometer.
  • the above-mentioned first window plate is capable of transmitting even infrared radiant light of a longer wavelength than the second window plate, and is provided with a means for controlling the substrate temperature. (1) or with the vacuum processing device described in ( 2 ),
  • the first and second infrared radiation thermometers are each configured to perform measurement at the same infrared wavelength, and the vacuum processing apparatus according to (1) or) may be used. Also,
  • the means for heating or cooling the temperature of the substrate in the temperature calibration chamber to a known predetermined temperature comprises means for bringing the substrate into thermal contact with a member having a larger heat capacity than the substrate.
  • the means for bringing the base body into thermal contact with a member having a larger heat capacity than the base body has a means for evacuating the space where the base body and the member come into contact with a vacuum, by the vacuum processing apparatus according to the above paragraph). Also,
  • the means for heating or cooling the temperature of the substrate on the temperature calibration stage to a known predetermined temperature is inside the vacuum processing chamber, and means for thermally contacting the substrate with a member having a larger heat capacity than the substrate. , In the space where the base and the forest contact
  • the vacuum processing apparatus according to any one of (1) to (7) above, which is provided with means for enclosing a gas having a pressure of 5 pascals or more. 3) The substrate temperature calibration stage, the vacuum processing chamber, and The vacuum processing apparatus according to (1) or ( 2 ) above, in which a substrate temperature adjusting chamber is provided between the two, and each stage is provided with the first, second, and third infrared radiation thermometers. , Also,
  • At least one of the means for heating the substrate in the vacuum processing chamber is the vacuum processing apparatus according to any one of the above ⁇ to (9), which comprises a lamp heating means.
  • At least one of the means for heating or cooling the substrate on the temperature calibration stage is provided in the stage, and at the same time, the second heating or cooling is provided close to the upper surface of the substrate.
  • Each of the stages in the vacuum processing chamber has a temperature for adjusting the amount of temperature deviated from the predetermined set temperature in the vacuum processing chamber from the temperature of the substrate obtained from the output of the second infrared radiation thermometer.
  • the vacuum processing apparatus according to any one of (1) to (12) above, comprising a control means.
  • a first infrared radiation thermometer for measuring radiant heat of a substrate on temperature calibration which is provided with means for heating or cooling the substrate placed on a stage to a known set temperature; the first infrared ray The emissivity is obtained from the output of the line radiation thermometer based on the known temperature of the substrate, and the emissivity is measured by the first infrared radiation thermometer.
  • a vacuum film formation processing chamber provided with means for performing vacuum film formation processing on the substrate; a second infrared radiation temperature for measuring radiant heat of the substrate on a stage in the vacuum film formation processing chamber.
  • the film is provided in close proximity to the substrate in the chamber and has a shutter mechanism whose main surface is calibrated by a member that is a mirror surface sufficiently for the measurement wavelength of the infrared thermometer. Achieved by the device. And more specifically,
  • the CVD film forming apparatus which comprises the vacuum film forming chamber formed of a vacuum film forming chamber capable of forming a thin film under a predetermined condition by the CVD method. To be done. Also, (21). A substrate temperature adjusting chamber is provided between the substrate temperature calibration chamber and the vacuum film formation chamber, and each chamber is equipped with an infrared radiation thermometer.
  • the set temperature of the substrate temperature adjusting chamber is kept at a temperature lower or higher than those of the substrate temperature calibration chamber and the vacuum film forming chamber on the substrate.
  • a second film forming step of forming a film to a predetermined film thickness by controlling the temperature of the substrate to a third film forming temperature higher than the second set temperature in the substrate temperature adjusting chamber.
  • a rapid cooling step which is achieved by the film forming method by the film forming apparatus according to the above (21).
  • the infrared radiation thermometer for measuring the temperature of the substrate whose temperature is to be measured and the surface of the substrate opposite to the surface of the substrate whose temperature is measured by the infrared radiation thermometer are Achieved by a substrate temperature measurement method in which a mirror surface with sufficient reflectance for the infrared wavelength to be measured is installed almost perpendicular to the optical axis measured by the radiation thermometer, and the temperature of the substrate is measured. To be done. Or
  • the infrared radiation thermometer for measuring the temperature of the substrate to be heat-treated or cooled and the temperature of the substrate, and the infrared radiation thermometer at the measurement wavelength on the opposite side of the substrate should be sufficient.
  • the method of controlling the substrate temperature including the mirror surface having a high reflectance and the heating or cooling means for performing the above treatment it is preferable that (28).
  • the method for controlling a substrate temperature according to (27) wherein the heating or cooling means controls the substrate to a predetermined temperature by the value measured by the infrared radiation thermometer.
  • the heating means performs at least the first and second heating, and after the first heating, the substrate temperature is measured using the mirror surface and the infrared radiation thermometer.
  • the substrate Before subjecting the substrate to the prescribed processing in the vacuum processing chamber, in the temperature calibration stage, the substrate is heated or cooled to a known temperature and the first infrared radiation thermometer and thermocouple are used to The temperature is measured, and the infrared radiation thermometer correction value, that is, the emissivity is calculated based on the measurement result. Based on the result of this deduction, the temperature of the substrate in the subsequent vacuum processing chamber is accurately measured by the second and third thermometers. And that The temperature control system is operated based on the measurement result of 1. to set the temperature of the substrate in the vacuum processing chamber to a predetermined value, and vacuum processing such as film forming processing is performed in a precisely temperature-controlled state.
  • the temperature of the substrate is controlled in the vacuum processing chamber thereafter by measuring the calibration temperature with the first infrared radiation thermometer and thermocouple at different temperatures. It is possible to control the process temperature in a wide temperature range when performing -1.
  • thermometer and thermocouple by providing a plurality of means as heating means or cooling means for measuring the calibration temperature by the above-mentioned first infrared radiation thermometer and thermocouple, calibration at different temperatures can be performed in a shorter time. Can be done in.
  • thermometer instead of using the first infrared thermometer described above, it is also possible to obtain the emissivity by obtaining the absorptance from the reflectance and the transmissivity using the lamp of the measurement wavelength.
  • thermometer In order to observe the substrate with an infrared radiation thermometer while heating or cooling the substrate, it is necessary to provide a through hole (opening window) in the heating or cooling stage, but this through hole does not affect the temperature distribution of the substrate. Uniformity may occur. Therefore, as a countermeasure against this, it is possible to heat both the front and back sides of the substrate, but the stage is divided into two, and one of the substrate heating or cooling stages is not provided with an opening window and is dedicated to temperature control. Opening window on the other temperature measuring stage When providing the temperature measurement, the temperature may be measured by moving the substrate from the one stage to the other stage.
  • disposing the shutter close to the substrate when measuring the temperature of the substrate plays an extremely important role in accurately measuring the temperature of the substrate.
  • the first role is that in the case of a device that deposits a metal film by sputtering or CVD, regardless of the presence or absence of the metal film, the infrared rays are the same as when the metal film is deposited by this shutter. Since the emissivity can be obtained, it is possible to correct the apparent difference in the infrared emissivity before and after film formation, and to enable correct temperature control of the substrate based on accurate temperature measurement.
  • the second role is to block stray light penetrating the substrate and entering the infrared radiation thermometer to prevent measurement errors due to stray light.
  • This shutter mechanism is indispensable especially on the thermometer side of the substrate before film formation.
  • an absorber is used together with the shutter, the level of the stray light component can be accurately obtained in the measurement with the absorber being used, so the measurement boundary due to stray light can always be known.
  • FIG. 1 is a schematic partial cross-sectional block diagram of a vacuum processing apparatus showing an embodiment of the present invention
  • FIG. FIG. 3 is a schematic cross-sectional block diagram showing an example of a stage
  • FIG. 3 is a partial cross-sectional block diagram showing a vacuum processing apparatus according to another embodiment of the present invention
  • FIG. 5 is a partial cross-sectional block diagram for schematically explaining a vacuum processing apparatus showing another embodiment of the present invention
  • FIG. 5 and FIG. 6 are a sputter stage and a substrate, respectively, in which a shutter mechanism is arranged.
  • Fig. 7 is a schematic cross-sectional configuration diagram showing an example of the temperature adjustment stage
  • FIG. 7 is a characteristic curve diagram showing the results of temperature measurement with and without shutters
  • Fig. 8 is a combination of window plate materials.
  • FIG. 9 shows infrared transmission characteristics of Ba F 2 (barium fluoride)
  • FIG. 10 shows the same in the case of Ca F 2 (calcium fluoride).
  • FIG. 11 shows another preferred embodiment of the present invention
  • FIG. 12 shows a sectional view of a stage according to another embodiment of the present invention in which the stage is divided into two in the same chamber
  • FIG. FIG. 14 is a cross-sectional view of a stage in which temperature control means is provided on both sides of a substrate
  • FIG. 14 is an explanatory view showing one temperature profile during film formation.
  • the infrared radiation thermometer is used as the main means of thermometry, it is calibrated for each substrate (for example, silicon wafer). Specifically, each substrate is heated or cooled to a known temperature before the substrate is processed by the target vacuum processing device, and the temperature of one or more points is increased. In, the temperature of the substrate is measured by the first infrared radiation thermometer. From the reading of the first infrared radiation thermometer obtained at this time, correct the infrared radiation thermometer in the vacuum processing chamber after the temperature calibration stage. Of course, the emissivity can be obtained by other means. Depending on the product, it is possible to save labor by doing this for each mouth.
  • the infrared radiation thermometer after the temperature calibration stage is calibrated, for example, with a rough correction, or with a single coefficient for a narrow temperature range. If there are multiple temperature calibration points, there is a method such as importing each temperature calibration data into the computer and performing calculation for correction.
  • the temperature calibration stage described above is not limited to vacuum, but may be under atmospheric pressure. In an atmospheric pressure environment, not only is the structure of the device generally simple, but it is easier to control the temperature of the target uhha to the temperature of the heat block (stage) heated or cooled to a known temperature. It is possible to approach.
  • a vacuum chuck can be used on the stage to bring the substrate into close contact with a heat block having a larger heat capacity than the substrate. This is possible, and by doing so, the temperature of the substrate can be brought closer to the heat block temperature more accurately and in a short time.
  • the atmosphere of the chamber with the temperature calibration stage should be replaced with the atmosphere, for example, nitrogen atmosphere. More preferred.
  • the substrate when the substrate that was in the atmosphere is taken into the vacuum processing tank, the substrate is removed in order to sufficiently remove the moisture adsorbed on the substrate surface.
  • the temperature of the substrate which has already been heated up and raised is lowered to a film formation start temperature of, for example, about 100 in the vacuum chamber.
  • a film formation start temperature for example, about 100 in the vacuum chamber.
  • the substrate is heated or cooled to a known temperature in advance before the predetermined vacuum treatment, and the substrate temperature is measured by the first infrared radiation thermometer.
  • One or more secondary infrared radiation thermometers for use in the processing process Is equipped with a function to calibrate the
  • a film-forming device that needs to accurately control the temperature of the substrate, such as a CVD device, is configured, a process more suitable for electronic components can be realized.
  • the first and second infrared radiation thermometers described above can be calibrated more accurately if they are measured at the same infrared wavelength.
  • the above-mentioned first infrared radiation thermometer is calibrated at a known temperature with a heated substrate, if heating to a known temperature is performed in a vacuum, it is a so-called so-called “removal of moisture adsorbed on the substrate”. Since it can also be used as a single quenching process, the scale of the device can be reduced, which is preferable in some cases.
  • the infrared radiation temperature is set in advance. If the meter is calibrated, the radiant heating by the lamp can be performed instead of using the heat book, and a cheaper sputtering device can be constructed.
  • the lamp light may enter the infrared radiation thermometer as stray light.
  • the measurement wavelength of the infrared radiation temperature Kuraj is the same as the wavelength radiated by the lamp. Are essentially different wavelength ranges.
  • a mirror surface is installed on the side of the substrate opposite to the side where the infrared temperature is present. like this In this way, the temperature can be obtained in this way during the lamp heating, and the additional heating conditions can be determined from the result.
  • the infrared lamp containing silica glass which is widely used, cannot perform efficient heating.
  • this type of infrared lamp is prone to stray light with respect to the infrared radiation thermometer, it is more preferable to use a lamp with a short wavelength, which has a high absorption efficiency in the silicon microwave.
  • the temperature at which film formation on the substrate starts in the vacuum processing chamber is lower than the baking heating temperature in vacuum for removing the adsorbed moisture from the substrate, after baking, It is necessary to cool the substrate to a predetermined temperature in a vacuum chamber and adjust the substrate to a predetermined film formation start temperature.
  • a stage equipped with a first infrared radiation thermometer for performing temperature calibration in the temperature calibration chamber and baking of the substrate in vacuum are provided. And a stage for cooling the film to a temperature at which a predetermined film formation is started before starting the film formation, and the substrate temperature on the cooling stage is calculated by the correction value obtained by the first infrared radiation thermometer.
  • a sputtering device equipped with a second infrared radiation thermometer that can be accurately measured by calculation and use is required.
  • the substrate is close to the surface on the opposite side of the surface observed by the infrared radiation thermometer through the opening window of the stage to the measurement wavelength of the infrared radiation thermometer.
  • a shutter mechanism whose main surface is composed of a member that is sufficiently mirror surface, it is possible to block stray light penetrating the base and entering the infrared radiation thermometer.
  • FIG. 1 is a schematic configuration diagram showing an embodiment in which the vacuum processing apparatus of the present invention is applied to a sputtering film forming apparatus.
  • the substrate to be deposited is a silicon wafer and the A thin film is deposited on the substrate by sputtering.
  • the vacuum processing apparatus 1 of the present invention comprises a substrate temperature calibration chamber 2 having a substrate temperature calibration stage 5, a substrate temperature regulation chamber 3 having a substrate temperature regulation stage 6 for heating and cooling the substrate, and a sputtering system. It consists of a film stage 7, an A target 8 and a sputter deposition chamber 4 with a sputter electrode 9. And these chambers are connected by gate valves GV 1 and GV 2, respectively, and are independent. In addition, an exhaust system is connected to the substrate temperature calibration chamber 2 and the sputtering film formation chamber 4, so that one side can maintain a predetermined vacuum state and the other side uses gas.
  • a predetermined gas is introduced from the inlet, and air or nitrogen gas can be introduced to the substrate temperature calibration chamber 2 to set it to atmospheric pressure, and sputter gas is introduced to the sputter deposition chamber 4 by a predetermined discharge. It is configured so that it can be set in the environment in which plasma occurs. Furthermore, each stage is provided with heating and cooling means as will be described later, and an opening window 19 consisting of a through-hole for observing radiant infrared rays from the substrate 10 is provided. The first, second and third infrared radiation thermometers 11, 1, 14 and 15 are optically coupled to each other through this opening window 19 and are connected to the substrate temperature configuration stage 5. A thermocouple 12 is provided to accurately measure the temperature of stage 5.
  • thermocouple 12 input the output from each infrared radiation thermometer and the output of thermocouple 12 to calculate the emissivity of the first infrared radiation thermometer 11 or to calculate the emissivity of the second infrared radiation thermometer 1 2 based on this calculation result.
  • the infrared radiation thermometers 14 and 15 are corrected to measure the correct temperature of the substrate 10 on each stage, and finally the prescribed stage temperature is also based on these measured data.
  • Substrate temperature controller for controlling the temperature of the entire so-called vacuum processing apparatus by feeding back the command to set to the heating and cooling means of each stage to control the temperature of the stage to a predetermined value 1 Equipped with 3.
  • the substrate temperature calibration chamber normally emits infrared radiation from the substrate 10 which is set to a known temperature higher than the film formation start temperature.
  • Infrared radiation thermometer 1 1 1 Measure and measure the emissivity to calibrate this infrared radiation thermometer.
  • the substrate temperature adjustment chamber 3 has a temperature adjustment function before the substrate is transferred to the next sputter film formation chamber 4, and the sputter film formation chamber 4 has a function of forming a film on the substrate by sputtering.
  • the well-known 10 is set to 2 0 0'C and 300 on the calibration stage 5, and is gradually stepped to 3 temperature points at 4 00. Is heated to.
  • the 0 heating and cooling methods in these stages 5, 6 and 7 will be collectively described later.
  • the back surface of the base body 1.0 heated on the calibration stage 5 is observed and measured by the first infrared radiation thermometer 11 and the thermocouple 12 and the arithmetic processing unit of the base body temperature controller 13 is observed.
  • the temperature readings for each temperature step are obtained with. That is, the temperature of the calibration stage, which is parallel to the substrate temperature, is measured with the thermocouple 12 and the emissivity at that time is taken as the substrate temperature, and the emissivity at that time is observed with the infrared radiation thermometer 11 to determine the substrate temperature controller.
  • the temperature calculation value based on this emissivity is obtained by the arithmetic processing unit of 13.
  • the emissivity obtained from this first infrared radiation thermometer 11 can be inversely determined, and so in subsequent vacuums.
  • the emissivity was used to correct the emissivity from the second and third infrared radiation thermometers 14 and 15. Read.
  • the inside of the substrate temperature calibration chamber 2 is evacuated to the empty state, and then the wafer 10 is set to the gate valve GV 1. It is opened and transferred from the calibration chamber 2 to the substrate temperature adjustment chamber 3 under vacuum, and the temperature is measured by the second infrared radiation thermometer 1 4. Based on the measurement results, the temperature of the stage 6 is adjusted by the substrate degree controller 13 and the temperature of the wafer 10 is adjusted to an arbitrary temperature. In this example, the wafer set at 100 ⁇ and then the wafer 10 is transferred to the stage 7 of the vacuum sputter deposition chamber 4 by opening the gate valve GV2, and the third infrared radiation thermometer.
  • the temperature is measured by 15 and based on the result, the temperature of the stage 7 is adjusted to an arbitrary temperature, and the temperature of the substrate 10 is controlled to an arbitrary temperature to perform sputtering film formation.
  • a set of 2 0 'C, A £ sno. Film formation was performed.
  • the wafer 10 was transported to the calibration chamber 2 again, and the emissivity was re-calibrated, and this emissivity was used to correct the temperature measurement during the subsequent sputter film formation.
  • a transport mechanism using a heat resistant belt such as silicone rubber or a robot is used.
  • the structure of the stage on which the substrate is placed is The outline, the heating and cooling methods, and the method for measuring the emissivity of the wafer will be described using an example of the sputtering stage 7.
  • the sputter stage 7 has a built-in electrothermal heater 18 for heating the stage and transfers heat to the wafer in vacuum.For example, it has a structure in which heat transfer gas such as air or nitrogen gas flows. A clamp 17 is installed to make the heat transfer gas contact uniformly. In addition, the temperature of the woofer
  • an opening window 19 that constitutes a radiation observation cavity for measurement with an external radiation thermometer 15.
  • a cooling medium such as Freon is circulated instead of the heater 18 to cool the stage, and the wafer is cooled by the heat transfer gas in the same manner as above.
  • the heat transfer gas is not used and the chamber is evacuated and the vacuum chuck is used to maintain the adhesion to the stage and transfer heat by heat conduction. It has become.
  • an infrared radiation thermometer lis 1 15 is installed at the bottom of each stage to measure the temperature on the backside of the wafer, so that stray light from inside each chamber does not enter the infrared thermometer.
  • a stray light blocking cylinder 16 is installed between each stage and the infrared radiation thermometer.
  • the treatment in vacuum is the film formation of i ⁇ on the substrate by sputtering 7.
  • the emissivity increases significantly due to the reflection from the A film. Therefore, the emissivity obtained by measuring with the substrate temperature calibration chamber before the film formation process cannot be used due to the subsequent film formation process.
  • the wafer after the film formation process is heated again to a known temperature set in advance by the composition chamber, the emissivity is measured again on the new surface, and recalibration is performed. Therefore, for example, by measuring the wafer just after the film formation with an infrared radiation thermometer and measuring the emissivity after the film formation (second time) to obtain the correct emissivity, It is possible to know the wafer temperature correctly.
  • the heating condition setting is changed so as to reduce the amount of substrate heating performed during film formation or before film formation.
  • the apparent infrared emissivity value may vary greatly depending on the presence or absence of the film.
  • the second temperature calibration chamber 32 is used to calibrate the infrared emissivity of the substrate after film formation, and the spa
  • the figure shows an example in which a film is added to the deposition chamber 4 and added.
  • the temperature of the substrate is measured with an infrared radiation thermometer 15 during film formation by sputtering.
  • the infrared emissivity correction value obtained in the substrate temperature calibration stage 2 cannot be used.
  • the substrate 10 is transferred from the sputtering film formation chamber 4 to the second temperature calibration chamber 32, and the heating or cooling stage 3 3 is transferred in the same manner as the temperature calibration chamber 2. Heating or cooling to a specified temperature with, the temperature is measured with an infrared radiation thermometer 34 and a thermocouple 35, and the infrared emissivity of the substrate 10 after film formation at the specified temperature is calculated from the indicated values of both.
  • the temperature of the substrate during film formation can be accurately known. If the temperature of the substrate 10 during film formation obtained in this way is higher than the predetermined value, the heating means of the substrate temperature adjusting chamber 3 or the heating means of the substrate temperature adjusting chamber 3 must be adjusted to properly adjust the temperature of the substrate. Alternatively, by appropriately feeding feedback to the cooling means, the film forming process for the next substrate can be properly performed.
  • the temperature calibration chamber for calibrating the infrared emissivity of the substrate after film formation is not necessarily separate from the temperature calibration chamber 2 for calibrating the infrared emissivity of the substrate before film formation, as in this example. No need to prepare. That is, after the film formation is performed by the sputter film formation chamber 4, the substrate is conveyed again to the temperature calibration chamber 2 via the substrate temperature adjustment chamber 3 and here, the second temperature calibration chamber 3 is used. The same infrared emissivity calibration as in 2 may be performed.
  • This embodiment also describes an example of an apparatus for forming aluminum A £ on a silicon substrate by sputtering, as in the first embodiment.
  • FIG. 4 shows a schematic configuration diagram of the sputtering apparatus, which is basically the same as FIG. 1, but in this example, as will be described later in detail, the substrate 10 mounted on each stage is The shutters 20, 21 and 22 are arranged in close proximity to each other.
  • the substrate 10 is first heated or cooled to a predetermined temperature by the heating or cooling stage 5 in the temperature calibration chamber 2 and the temperature is measured by the first infrared radiation thermometer 1 1 and the thermocouple 1 2 and both instructions are given.
  • the infrared emissivity of the substrate 10 at a given temperature is calculated from the value.
  • the apparent infrared emissivity value may vary greatly depending on the presence or absence of the film. Therefore, the difference in apparent infrared emissivity due to the presence or absence of the film can be reduced.
  • the shutter 20 should be closed.
  • the substrate 10 is transferred from the temperature calibration chamber 2 to the substrate temperature adjusting chamber 3 and heated or cooled by the heating or cooling soot 6 while the substrate 10 is heated by the second infrared radiation thermometer 14.
  • the temperature of the heating or cooling stage 6 is adjusted to the specified temperature through the substrate temperature controller 13 by correcting the emissivity value of the substrate 10 at the specified temperature obtained by the calibration chamber 2.
  • the temperature of the substrate 10 is adjusted to a predetermined temperature. As with the temperature calibration chamber 2, the temperature on the thermometer side of the substrate temperature adjustment chamber 3 is also measured with the shutter 21 closed.
  • the substrate 10 is transferred to the sputtering film forming chamber 4 and heated or cooled by the sputtering stage 7.
  • the shutter 22 is closed on the substrate, and the third infrared radiation thermometer
  • the temperature of the base body 10 can be measured by means of 15 and the correct temperature can be known by correcting it with the emissivity value of the base body 10 obtained by the calibration chamber 2. Further, by knowing the correct temperature in this way, the temperature of the heating or cooling stage 7 is adjusted to a predetermined temperature through the substrate temperature controller 13 and the temperature of the substrate 10 is controlled to a predetermined temperature to effect sputtering. Start film formation.
  • the substrate 10 is returned to the substrate temperature adjusting chamber 3, and the temperature is measured by the second infrared radiation thermometer 14 while being heated or cooled at the stage 6.
  • the temperature of the stage 6 is adjusted to the predetermined temperature through the substrate temperature controller 13 and the substrate temperature is set to the predetermined value. Set to.
  • the substrate is unloaded from the vacuum processing apparatus 1 through the temperature calibration chamber 2 and proceeds to the next step.
  • the temperature measurement of the first infrared thermometer 11 and the temperature of the substrate 10 by the thermocouple 12 in the substrate temperature calibration stage 2 was performed at a plurality of temperatures, and the second and third infrared radiation thermometers 1
  • the use of 4 and 15 enables more accurate control of the process temperature.
  • by providing a plurality of means for heating or cooling the substrate for measurement with the first infrared radiation thermometer 11 for calibrating the substrate temperature it is possible to measure the substrate at a plurality of similar temperatures. The temperature can be calibrated in a shorter time.
  • the temperature calibration is described as being incorporated in the sputtering device, but it is also possible to prepare it separately as mentioned above.
  • a means for measuring reflection and transmission can be used instead of the first infrared thermometer.
  • Figure 5 shows a schematic diagram of the sputter stage 7 in Figure 4 as a representative example of the stage.
  • the structure of the stage is basically the same as that of the example of FIG. 2, except that the shutter 2 2 is provided in the vicinity of the upper part of the base 10 in this embodiment.
  • the apparent infrared emissivity value may vary greatly depending on the presence or absence of the film. Since the difference in apparent infrared emissivity due to the presence or absence of the film can be reduced by installing the sensor, the measurement by the infrared thermometer for temperature calibration as shown in Fig. 3 and the second temperature calibration chamber 3 2 are installed. As a result, it is no longer necessary to perform twice before and after film formation, and only once.
  • This shutter has an openable and closable mechanism that closes the substrate surface during temperature measurement and opens during film formation.
  • a stainless steel disc is supported by a rotatable drive shaft. It is configured to open and close by rotating.
  • an infrared A shutter 22 whose main surface is composed of a member that is sufficiently specular for the measurement wavelength of the radiation thermometer is provided. Is configured to block so as not to enter.
  • the role of the shutter mechanism is to firstly correct the increase in the apparent emissivity due to the radiated light from the wafer reflected by the metal film when the metal film is formed on the wafer substrate.
  • the second is the improvement of measurement accuracy due to the improvement of the infrared radiation intensity
  • the third is the blocking of stray light.
  • Fig. 6 shows a schematic configuration diagram of stage 6 in Fig. 4, which is basically the same configuration as stage 7 in Fig. 5.
  • the stage 6 has a built-in heater 18 and has a structure in which the heat transfer gas flows in the space between the stage 6 and the base body 10 in vacuum, so that the heat transfer gas can be brought into uniform contact with the base body.
  • Clamp 17 is installed.
  • An opening window 19 for measuring the temperature of the substrate 10 with an infrared radiation thermometer 14 and a stray light blocking cylinder 16 are connected, and a window plate 2 made of a material that transmits infrared rays is provided at both ends of the cylinder 16. 3 and 24 are installed.
  • the structure is such that the cylinder 16 itself is heated and water-cooled so that it does not become a source of stray light. To further reduce the effect of stray light, it is possible to cool it and then subject the inner wall of the cylinder 16 to a blackbody treatment.
  • the shutter 21 is arranged in the vicinity of the base body 10 in the same manner as in FIG.
  • the shutter may have any structure as long as (1) it has an infrared reflectance in a specular state, and ( 2 ) it has a function of blocking stray light. For example, it is synchronized with the temperature measurement timing of the substrate.
  • Various configurations can be adopted, such as a structure in which the substrate is driven to open and close freely, or a fixed shutter is provided in one region of the chamber and the substrate is moved to the lower part of the shutter during measurement. If the shutter temperature drops due to the appearance of this shutter on the wafer, it is advisable to heat the shutter temperature close to the approximate temperature.
  • FIG. 7 is a characteristic curve showing the difference in infrared emissivity of the silicon wafer substrate with and without shutters.
  • FIG. 7 (a) shows the comparative example without a shutter
  • FIG. 7 (b) shows the measurement result of the present example with the shutter.
  • the apparent infrared emissivity of the wafer before the aluminum ⁇ film formation (without the ⁇ film) in Fig. 7) is smaller than the apparent infrared emissivity rate of HUHA after the film formation (with the A £ film).
  • the apparent infrared emissivity after deposition of A is shown in Fig. 7 (b). It turned out to be almost the same as Uha. From this, it can be seen that it is possible to measure at a constant emissivity by measuring the substrate temperature using a shutter.
  • the temperature observation window plate made of a material that is almost transparent to the measurement wavelength of the infrared radiation thermometer has its own temperature raised. As a result, synchrotron radiation is emitted, which limits the lower limit temperature of measurement.
  • the lower limit temperature for measurement can be lowered by using different materials for the first and second window plates will be described using the sputtering stage 7 in FIG.
  • no shutter is used on the substrate, but it goes without saying that the same purpose can be achieved by using a shutter.
  • An electric heater 18 is provided inside the sputter stage 7-1. If a coolant such as liquid nitrogen is introduced into the sputter stage 7 instead of the heater, it can be used for cooling the substrate.
  • Reference numeral 30 denotes a small window provided on the sputter stage 7-1, in which the first window plate 24 is fitted.
  • a material that can transmit infrared rays efficiently such as barium fluoride or calcium fluoride, is used. For this reason, the airtightness of the space formed by the substrate 10 and the sputter stage 7 is maintained, and the pressure in this space is kept at a suitable pressure within a few Torr.
  • the optical path 3 It is provided to pass 6.
  • the infrared thermometer 14 is installed in the atmosphere. For this reason, the optical path 36 must pass through the boundary between the atmosphere and the vacuum. 3 1 is an observation window for this purpose, and the second window plate 2 3 will be described later, but a material that transmits infrared rays efficiently, for example, Futsui Imano, 'ryuum, Futsui Imano canalium, etc. are used. Since this second window plate 23 has to withstand atmospheric pressure, it is usually done with a thickness of about 5 l to secure its strength.
  • '32 is to introduce Ar gas into the space formed by the substrate 10 and the sputter stage.
  • the sputter stage 7-1 is preheated to a predetermined temperature, the substrate 10 is placed, the substrate 10 is pressed against the sputter stage 7-1 by the clamp 17 and Ar gas is introduced. Then, the heat transfer from the sputter stage 7-1 to the substrate 10 starts, and the substrate temperature starts to rise rapidly.
  • the sputtering target 8 installed facing the substrate 10 may start a process such as film formation by sputtering. If it is too low, adjust the temperature of the scatter stage and continue heating until it reaches the specified temperature.
  • the first window plate 24 which comes into direct contact with the gas as the heating medium filling the space created by the substrate 10 and the sputter stage 7-1, is the same as the substrate 10. Is heated by the heat medium.
  • the infrared thermometer 14 "sees" the substrate through the first window plate 2 4 and the second window plate 2 3, but the second window plate 2 3 will be described later.
  • the window plate 24 will be described first. If the thickness of the first window plate 2 4 is large, it will The intensity of the infrared radiant light is reduced. Similarly, the fact that the thickness of the first window plate 24 is large and the absorption loss is large means that when the temperature of the first window plate 24 rises, radiation from the partition plate itself is generated accordingly. I mean.
  • the thickness of the first window plate 24 be as thin as possible. If the first window plate 24 separates the atmosphere directly from the substrate and the space between the sputter stage and the stutter stage, as described above, in order to provide strength to withstand atmospheric pressure, a thickness of about 5 «is provided. Is necessary. However, if barium fluoride with a thickness of 5 «is heated to 400 ⁇ c, extremely strong radiation will occur and the infrared radiation from the substrate 10 placed ahead of it will be observed. Can not. Moreover, since the first window plate 24 and the substrate 10 use the heating method using gas, both of them move to converge to the same temperature. Therefore, from this point as well, the first window plate 24 needs to be thin.
  • both the first and second window plates 24 and 23 must be made of a material such as fluorinated fluoride.
  • the normal pressure of Ar for sputtering the first window plate 24 is several m Torr.
  • the pressure in the space formed by the substrate 10 and the sputter stage 7-1 is several Torr in height. Therefore, the pressure applied to the front and rear of the first partition plate 14 is very small.
  • the partition plate does not need strength. This is because the second window plate 23 is responsible for the interface with atmospheric pressure. Therefore, the first window plate 2 4 is enough for strength if it has a thickness of 1 «.
  • Figure 9 shows the infrared transmission characteristics of barium fluoride. This characteristic was shown at room temperature and 500 ⁇ Data source is “Characteristics of Physical Properties” (Kyoritsu Shuppan, May 15, 1974, 1st printing, 1st printing), pages 4 9 1 to 4 9 2 Barium fluoride), pages 468 to 469 (calcium fluoride).
  • the substrate When depositing by sputtering A, the substrate is
  • the first window plate 24 will be radiated by raising the temperature to 500 ° C. Infrared light is transmitted through the second window plate 23 because the second window plate 23 is at room temperature. It is also observed that it is infrared light from substrate 10.
  • Figure 10 shows the infrared light transmission characteristics of calcium fluoride at room temperature, but the transmission characteristics are extended to longer wavelengths than the transmission characteristics of room temperature fluoride shown in Figure 9. I know that not. If this calcium fluoride is used for the second window plate 23, even if the first window plate 2 is heated and starts to radiate by itself, this infrared radiation will be emitted after the partition plate 24. This unwanted radiation does not enter the infrared thermometer 14 that is being reserved. ⁇ Thus, stable measurement is possible regardless of the temperature of the first window plate 24.
  • Reference numeral 30 is a small window provided on the sputter stage 7 and is used to detect infrared radiation emitted from the back surface of the substrate (in this example, Si uh) 10 placed on the sputter stage 7-1. External line (radiation) It is provided to pass the optical path 36 for observation with the thermometer 5.
  • the infrared thermometer 14 is installed in the atmosphere. For this reason, the optical path 36 must pass through the boundary between the atmosphere and the vacuum.
  • Yes. 2 3 is a window for this purpose, and the window material is made of a material that efficiently transmits infrared rays, such as barium fluoride or fluorine-containing power.
  • the pipe 8 is for introducing Ar gas into the space defined by the substrate 10 and the sputtering stage.
  • the substrate 10 is clamped by the clamp 17 to the spatter stage.
  • the small window 30 of the sputter stage 7-1 is sealed by the lid 35. That is, the lid 35 is supported by the crank-shaped drive shaft 34, and the drive shaft 34 can move up and down. In Fig. 11 the lid is lowered to the midway position, but the lid 35 can be lowered further and it can be rotated after it has reached the position sufficiently lower than the spatter stage 7-1. , It is possible to retract the observation optical path 36 of the infrared thermometer to a position where it does not interfere.
  • the drive shaft 3 4 can be lifted from the position shown in Fig. 9, and at the top dead center, the small window 30 of the sputter stage 7 — 1 can be completely closed by the lid 3 5 from below. ..
  • the drive shaft 34 has risen to the top dead center and is closed by the lid 35 of the small window 30 of the slaughter stage 7-1. In this way, heat transfer from the sputter stage 7-1 to the substrate 10 starts, and the temperature of the substrate begins to rise rapidly.
  • the drive shaft 35 is rotated downward, and it is removed from the optical path 36, so that the infrared thermometer 14 can observe the back surface of the substrate 10. Since the lid 35 is lowered, the gas pressure of several Torr cannot be maintained between the back surface of the substrate 10 and the sputter stage 7-1, so that the temperature rise of the substrate 10 is almost stopped.
  • a sputtering target 8 installed facing the substrate 10 may start a process such as film formation by sputtering, or if it seems too low. If so, use lid 35 again and continue heating by filling it with gas.
  • the through hole (opening window) 19 as shown in Fig. 12 may be used. After heating or cooling the substrate 10 with a stage 25 dedicated to heating or cooling provided separately in a remote place, the substrate 10 is transferred to a stage having an opening window 19 and the infrared radiation thermometer is transferred. With the configuration in which the temperature is measured at 27, the temperature distribution of the substrate 10 can be measured in a more uniform state.
  • Example 7
  • the substrate When the substrate is heated or cooled only from either the front side or the back side, a temperature difference occurs between the front side and the back side of the substrate. Therefore, by providing heating or cooling means 28 and 29 on each side so that the temperature can be controlled from both the front and back sides of the substrate as shown in Fig. 13, the temperature difference between the two sides can be controlled. Can be reduced. Further, by this, the nonuniformity of the temperature distribution on the substrate due to the opening window 19 can also be reduced.
  • the silicon wafer 10 is heated to 500 at the temperature calibration chamber 2 to remove adsorbed moisture, etc., and the temperature is measured by the thermocouple 12 and the infrared radiation thermometer 1 1 is used as a base. The emissivity is calibrated, and the uhha is then transported to the substrate temperature control chamber 3.
  • This emissivity calibration can also be performed by irradiating the uch with light of the measurement wavelength, without depending on this method, to determine the transmissivity / reflectance.
  • the HUHA substrate 10 transferred to the substrate temperature adjustment chamber 3 is measured by the infrared radiation thermometer 14 and cooled to a predetermined temperature of 200 by the temperature control of the stage 6. And transferred to the sputtering film forming chamber 4.
  • the substrate 10 is snow-coated by a temperature profile as shown in FIG. Target 8 had a composition of 1% Si-3% Cu-A ⁇ .
  • the temperature of the substrate 10 is controlled to 230, and the film)! :number
  • the first sputter film formation up to 100 A is carried out, the sputter is once stopped, and the substrate is transferred to the substrate temperature adjusting chamber 3.
  • the temperature of the substrate 10 is controlled to 300 ° (: by heating, and the crystal grains of the A ⁇ film obtained by the first sputter deposition are grown to improve the orientation and the like.
  • the substrate is again conveyed to the subcatalyst film forming chamber 4, and after setting the substrate temperature to about 400, the second sputter film formation is restarted and the film is formed to a film thickness of about 1 m.
  • a silicon substrate is used as a substrate and an A & thin film is formed on the surface by sputtering.
  • the temperature of the substrate can be controlled with high accuracy via the stage, the wafer can be controlled with high accuracy.
  • the crystallinity and the thin film microstructure with good reproducibility were obtained, and it was possible to achieve high quality film formation. For example, when a thin film of several hundred people is heated at a heating temperature of 350, no improvement in crystallinity can be obtained. It was Therefore, such a film forming method cannot be industrially realized without the present invention capable of knowing an accurate temperature.
  • the vacuum processing apparatus of the present invention can be applied to a film forming apparatus using a CVD (Chem Dic Vapor Deposition) in addition to the above sputtering device.
  • CVD Chemical Vapor Deposition
  • this is effective when a tungsten substrate is used as a substrate and a tungsten film is formed on this substrate by a known method using CVD.
  • the degree of camellia of the temperature control of the substrate influences the quality of the formed film, and the film-forming apparatus of the present invention can sufficiently meet such requirements.
  • the film forming apparatus can be realized by using the vacuum processing chamber as the film forming processing chamber as in the above-described embodiment, the vacuum processing chamber can be used not only in the film forming chamber but also in the dry etching such as plasma etching. It is also possible to use a etching treatment chamber, and the temperature control of the substrate to be etched can be realized in the same manner as in the above-mentioned embodiment.
  • the present invention it is possible to accurately control the temperature of a substrate in a vacuum, to realize a vacuum processing apparatus capable of accurately controlling the temperature of a substrate, and to form a film on it.
  • a vacuum processing apparatus capable of accurately controlling the temperature of a substrate
  • a film on it By applying this to an apparatus, it is possible to easily control the temperature before and after film formation, which requires precise temperature control, and during film formation, and thus it is possible to form a high quality film.

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  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
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Abstract

Appareil de traitement sous vide permettant de soumettre à différents traitements des tranches de silicium dans un réservoir sous vide, et procédé de formation de pellicules utilisant ce dispositif, caractérisé par le fait que l'on règle la température des tranches pendant la formation de la pellicule en utilisant un thermomètre à radiation, les tranches étant notamment transportées vers chaque étage dans une chambre de formation de pellicule sous vide, après correction de leurs émittances par un étage de correction de température combiné avec le volet, et leur température est régulée à une valeur définie afin de former une pellicule en surface.
PCT/JP1990/001601 1989-12-11 1990-12-10 Appareil de traitement sous vide et procede de formation de pellicules utilisant ledit appareil WO1991009148A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
DE19904092221 DE4092221T1 (fr) 1989-12-11 1990-12-10
DE4092221A DE4092221C2 (de) 1989-12-11 1990-12-10 Vakuumverarbeitungsapparatur und Vakuumverarbeitungsverfahren
KR1019910700879A KR940007608B1 (ko) 1989-12-11 1990-12-10 진공처리 장치 및 이를 이용한 성막장치와 성막방법
US08/260,321 US6171641B1 (en) 1989-12-11 1994-06-15 Vacuum processing apparatus, and a film deposition apparatus and a film deposition method both using the vacuum processing apparatus

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP1/318749 1989-12-11
JP31874989 1989-12-11
JP2225388A JP2923008B2 (ja) 1989-12-11 1990-08-29 成膜方法及び成膜装置
JP2/225388 1990-08-29

Publications (1)

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WO1991009148A1 true WO1991009148A1 (fr) 1991-06-27

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DE (2) DE4092221C2 (fr)
WO (1) WO1991009148A1 (fr)

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US7601409B2 (en) 2002-09-05 2009-10-13 Exxonmobil Chemical Patents Inc. Stretch film
CN104750140A (zh) * 2013-12-31 2015-07-01 北京北方微电子基地设备工艺研究中心有限责任公司 反应腔加热控制方法及装置
WO2016151968A1 (fr) * 2015-03-25 2016-09-29 住友化学株式会社 Dispositif de traitement de substrat et procédé de traitement de substrat

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US5562947A (en) * 1994-11-09 1996-10-08 Sony Corporation Method and apparatus for isolating a susceptor heating element from a chemical vapor deposition environment
JP4263761B1 (ja) 2008-01-17 2009-05-13 トヨタ自動車株式会社 減圧式加熱装置とその加熱方法および電子製品の製造方法
DE102008026002B9 (de) * 2008-05-29 2013-05-16 Von Ardenne Anlagentechnik Gmbh Verfahren zur Temperaturmessung an Substraten und Vakuumbeschichtungsanlage
US8900663B2 (en) 2009-12-28 2014-12-02 Gvd Corporation Methods for coating articles
DE102010009795B4 (de) * 2010-03-01 2014-05-15 Von Ardenne Anlagentechnik Gmbh Verfahren und Vorrichtung zur Herstellung von metallischen Rückkontakten für waferbasierte Solarzellen
JP5026549B2 (ja) * 2010-04-08 2012-09-12 シャープ株式会社 加熱制御システム、それを備えた成膜装置、および温度制御方法
GB202109051D0 (en) * 2021-06-24 2021-08-11 Lam Res Ag Device for holding a wafer-shaped article

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JPS5928627B2 (ja) * 1979-12-15 1984-07-14 工業技術院長 気相メッキ母材の温度測定方法
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7601409B2 (en) 2002-09-05 2009-10-13 Exxonmobil Chemical Patents Inc. Stretch film
CN104750140A (zh) * 2013-12-31 2015-07-01 北京北方微电子基地设备工艺研究中心有限责任公司 反应腔加热控制方法及装置
CN104750140B (zh) * 2013-12-31 2017-09-01 北京北方微电子基地设备工艺研究中心有限责任公司 反应腔加热控制方法及装置
WO2016151968A1 (fr) * 2015-03-25 2016-09-29 住友化学株式会社 Dispositif de traitement de substrat et procédé de traitement de substrat
US10294566B2 (en) 2015-03-25 2019-05-21 Sumitomo Chemical Company, Limited Substrate processing apparatus and substrate processing method

Also Published As

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DE4092221C2 (de) 1994-04-21
DE4092221T1 (fr) 1992-01-30

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