JP3334162B2 - Vacuum processing apparatus, film forming apparatus and film forming method using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum processing apparatus for performing various processes on a substrate in a vacuum, a film forming apparatus and a film forming method using the same, and more particularly to a semiconductor device manufacturing process. More particularly, the present invention relates to a vacuum processing apparatus, a film forming apparatus and a film forming method using the same.

[0002]

2. Description of the Related Art In a process apparatus used for manufacturing a semiconductor device, it is important to accurately control a process temperature in order to realize a well-controlled reaction or the like. A representative example of a process apparatus in which the temperature is the most important setting condition is a so-called furnace such as an oxidation furnace. The inside of this kind of furnace is an oxidizing atmosphere replaced with the atmosphere. In this case, the replacement atmosphere is at or above atmospheric pressure, and for example, a silicon wafer in the furnace body is heated by radiation from a heater installed around a quartz tube and heat conduction by the atmospheric pressure atmosphere in the quartz tube. . That is, since there is a medium for conducting heat, the temperature can be measured relatively accurately using a measuring element such as a thermocouple installed in the heat conducting atmosphere.

Further, as an example in which a heat conductive medium is not used, a photoresist baking apparatus used in a step of applying a photoresist used as a mask in an etching step can be exemplified. In this apparatus, baking is performed in an atmospheric pressure atmosphere, but the silicon wafer is placed on a heat block having a larger heat capacity than a silicon wafer heated to a predetermined baking temperature, and the silicon wafer is further provided on the heat block side. The entire surface of the silicon wafer is pressed against the heat block by atmospheric pressure using a vacuum chuck. Therefore, the temperature of the wafer 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 measuring element 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, often requiring processing in a vacuum.

Conventionally, accurate temperature control of a wafer in a vacuum in a semiconductor manufacturing apparatus has been essentially difficult for the following reasons.

That is, in the heating by the lamp heater, the wafer is heated only by the radiation because there is no medium for transmitting heat, and therefore, as is well known, only a small absorption occurs on a metal mirror surface and a large absorption occurs on a black body. Absorption occurs, and as a result, the degree of heating varies greatly depending on the surface condition of the heated wafer.

Attempts have been made to accurately measure the temperature of the wafer during processing by attaching a thermocouple to the wafer. However, in order to measure the temperature of the wafer while the thermocouple is in point contact with the wafer, the temperature of the thermocouple is reduced. It is difficult to stabilize the contact state to a constant level, and the measurement temperature has a drawback of poor reproducibility.

When a wafer is heated by infrared radiation, since the wafer is almost transparent in a wide range of the infrared region, heat is not transmitted to the thermocouple only by conduction from the wafer, but the thermocouple itself is heated. In some cases, the wafer may be heated by the lamp heater, and it is difficult to accurately measure the temperature of the wafer.

There is also a method of forcibly bringing a conductive medium into a vacuum. For example, as described in JP-A-56-48132 or JP-A-58-213434, a silicon wafer is clamped to a heat block installed in a vacuum atmosphere, and the back surface of the silicon wafer is connected to the heat block. By filling the gas with a pressure of about 1 Torr in between, the temperature of the wafer is equilibrated with the temperature of the heat block. In this case, the temperature of the heat block can be measured by a temperature measuring element such as a thermocouple attached to the heat block.

However, in this example, since the wafer is clamped to the heat block with a small force as compared with the use of a vacuum chuck under atmospheric pressure, the uniformity and reproducibility of the temperature are not sufficient. The biggest disadvantage is that the heat transfer from the heat block to the wafer takes time due to the low density of the heat transfer medium. Eventually, even if the heat block and the wafer reach thermal equilibrium, it takes several seconds to several tens of seconds as described in the above example,
Further, it is considered that various factors influence the reproducibility of the heat conduction time.

Further, in this method, since the surface of the substrate and the pressing member are in physical contact with each other, the surface of the substrate is contaminated or foreign matter is generated, thereby reducing product non-retention. I have.

As described above, whichever heating means is used, it is necessary to measure the temperature of the wafer in a non-contact manner in a vacuum. As one of the methods, there has been proposed a method of measuring a radiation intensity from a wafer in an infrared region using an infrared radiation thermometer.

That is, in this method, the temperature of a wafer is measured by an infrared radiation thermometer through a through hole formed in a target placed opposite to the wafer while the wafer is placed on a heat stage and heated in a sputtering apparatus. Things. That is, the infrared emissivity of the wafer at a specific temperature is measured in advance by another calibration sample, and the wafer temperature during sputtering is controlled by the measured value.

As a technique related to this kind of technology, for example, Japanese Patent Application Laid-Open No. 1-129966 can be mentioned.

[0014]

However, in this method, since the emissivity of the wafer is not always constant as described below, it is difficult to accurately measure the temperature, and there are some problems.

That is, the same metal as the target material, for example, another silicon wafer on which aluminum is deposited for several hundreds of degrees, is used as the calibration sample, but actually, the metal on the surface of the wafer to be observed by the infrared radiation thermometer is used. Depending on the presence or absence of the membrane,
Since the infrared emissivity from the wafer surface is different, it is not possible to control the temperature before film formation.

Further, even after the start of film formation, accurate temperature measurement cannot be performed until a film is formed to a certain thickness (for example, aluminum of several hundred degrees).

In order to accurately measure the temperature of a wafer in a vacuum and to control the temperature associated therewith, even if a wafer on which the same metal film is formed has a difference in infrared emissivity depending on the product lot, calibration is performed as in this example. In a method of separately preparing a wafer for use, accurate temperature control cannot be performed because the wafer is not a wafer on which a film is actually formed. As described above, in the vacuum processing apparatus conventionally used, various temperature control means are used, but none of them can accurately control the temperature of the process.

In a semiconductor material such as a Si wafer, the infrared emissivity increases with temperature. This is because the radiation and absorption due to the increase in the density of free carriers (metallization) increase with temperature. For details, see T. Sato; Japanese Journal of Applied Physics, Vo
l.6, No. 3 (1967).

Due to the variation of the emissivity with respect to the temperature,
When performing high-precision temperature measurement, emissivity correction at a plurality of temperatures is required. For this purpose, emissivity measurement at a plurality of temperatures in the temperature range to be measured may be performed in advance, but heating at this time substantially increases unnecessary heat treatment steps in the process. .

However, on the other hand, for a process requiring very high-precision temperature control, it is necessary to correct the emissivity for each wafer at a temperature as close as possible to the process temperature.

That is, the ideal method of controlling the temperature of a wafer using the infrared radiation temperature is to calibrate an infrared radiation thermometer using the wafer itself on which a film is actually formed, and to determine whether or not the film is present and the state of the film. This is a method that can be measured without being affected by the difference in emissivity. However, there has not yet been proposed any practical one.

In a vacuum processing apparatus having a plurality of vacuum processing chambers or a so-called multi-chamber type vacuum processing apparatus in which a vacuum processing chamber is arranged around a transfer chamber, a temperature measuring mechanism is installed in the vacuum processing chamber itself. In such a case, there are the following problems (1) obstacles caused by intrusion of thermal noise from a heat source in the vacuum processing chamber, (2) vacuum performance of the vacuum processing chamber, for example, increase in leak potential, ( 3) Contamination of the optical system and generation of dust due to the deposition of the film-forming particles. (4) In the case of application to an existing device, a vacuum device such as a substrate holder for mounting the substrate in a vacuum processing chamber. The necessity of changing design specifications, (5) Economic problems such as the necessity of a temperature measurement mechanism as many as the number of vacuum processing chambers, and high-precision temperature measurement Any practical approach in the coming technology has not been taken into account.

Accordingly, an object of the present invention is to solve the above-mentioned conventional problems, and a first object of the present invention is to provide an improved vacuum processing apparatus capable of accurately measuring and controlling the temperature of a substrate in a vacuum. The second object is to apply this vacuum processing apparatus, for example, a sputtering apparatus or a CVD (Chemical Va).
A third object is to provide a film forming apparatus such as a por deposition apparatus, and a third object of the present invention is to provide a film forming method using the improved film forming apparatus.

[0024]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted studies as described in detail below and obtained various findings.

That is, in the present invention, calibration is performed for each substrate (for example, a silicon wafer) in order to use an infrared radiation thermometer as a main temperature measuring means. Specifically, before performing the processing of the substrate by the target vacuum processing apparatus, at least one point of the lowest temperature as close as possible to the environmental temperature for each substrate in the stage in the temperature calibration chamber,
The temperature of the substrate is measured by a first infrared radiation thermometer. From the indicated value of the first infrared radiation thermometer obtained at this time, a correction is made to the infrared radiation thermometer in the vacuum processing chamber after the temperature calibration chamber. Specifically, by knowing this correction value in advance, the infrared radiation thermometer subsequent to the temperature calibration chamber is calibrated, for example, using a rough correction or a simple coefficient if the correction is for a narrow temperature range. In the case where a plurality of temperature correction points are provided, it is possible to adopt a method in which respective temperature correction data is created in advance by a computer and a calculation for correction is performed.

In a process requiring more accurate temperature measurement and control, a method of calibrating an infrared radiation thermometer at the process temperature can be employed.

The above-mentioned temperature calibration stage is not limited to a vacuum and may be in an environment of atmospheric pressure. Under atmospheric pressure environment, not only the device structure is generally simplified, but also
When heating or cooling to a known temperature, the temperature of the target wafer can be more easily brought close to the temperature of the heat block (stage).

More specifically, when the temperature calibration chamber is set at atmospheric pressure, it is possible to use a vacuum chuck on the stage to bring the substrate into close contact with a heat block having a larger heat capacity than the substrate. By doing so, the temperature of the substrate can be brought closer to the heat block temperature more accurately and in a short time.

Further, even when a heating block is not used and active heating or cooling is not performed, the substrate can be quickly brought to the stage temperature (in this case, the ambient temperature to 20 ° C.) by using the vacuum chuck. Can be balanced.

Further, instead of the above-mentioned vacuum chuck, an electrostatic chuck (by the lines of electrostatic force) can be used.

When it is necessary to raise the temperature at the above-mentioned temperature calibration point, a problem such as oxidation of the surface of the target substrate occurs depending on the atmosphere. Therefore, the atmosphere of the temperature calibration chamber is replaced with the atmosphere, For example, a nitrogen or argon atmosphere is more preferable.

When the temperature calibration chamber is set in a vacuum, in order to improve the heat conduction between the heat block and the base as described above, a heating or cooling gas is applied between the two at a pressure of 5 Pascal or more. By interposing as a conductive medium, the substrate temperature approaches the heat block in a relatively short time.

Further, the electrostatic chuck can be used to bring the base into contact with a heat block.

For example, in an apparatus for forming a thin film on a substrate by a sputtering method, when the substrate in the atmosphere is taken into a vacuum processing tank, moisture adsorbed on the surface of the substrate is sufficiently removed. For this reason, it is necessary to heat the substrate to 150 ° C. or higher, and conversely, it is necessary to lower the temperature of the substrate already heated to a film formation start temperature of about 50 ° C. in a vacuum chamber. There are cases where there is. In the case of the temperature increase and the temperature decrease, it is necessary to accurately measure the temperature each time the temperature is controlled, and it is necessary to calibrate the infrared radiation thermometer for measuring these temperatures in advance for each substrate.

That is, the substrate is controlled to a known temperature before performing a predetermined vacuum treatment, the emissivity of the substrate is measured by a first infrared radiation thermometer, and the subsequent vacuum treatment process is performed based on the measurement result. Provided with a function capable of calibrating one or more second infrared radiation thermometers used in the above, if a film forming apparatus that needs to accurately control the temperature of the substrate such as a sputtering apparatus or a CVD apparatus, A process more suitable for electronic components can be realized.

In general, the infrared radiation characteristics of a substance depend on the wavelength, so that the above-described measurement using the first and second infrared radiation thermometers can be performed at a wavelength in the same infrared region, thereby enabling more accurate calibration. And

When the emissivity measurement by the first infrared radiation thermometer at the above-mentioned known temperature is performed on the heated substrate, if the heating operation to the known temperature is performed in a vacuum, the moisture adsorbed on the substrate is removed. Can also be used as a so-called baking process, so that the scale of the apparatus can be reduced, which is preferable in some cases.

For example, when raising the temperature of the substrate in the vacuum processing chamber of the sputtering apparatus, if the infrared radiation thermometer has been calibrated in advance, instead of using a heat block, radiation heating by a lamp can be performed. A cheaper sputtering apparatus can be configured. When heating with a lamp in a vacuum processing chamber, the light of the lamp may enter the infrared radiation thermometer as stray light, so the measurement wavelength of the infrared radiation thermometer is different from the wavelength radiated by the lamp. Is essentially preferred.

When a silicon wafer is used as the base, for example, the silicon wafer is almost transparent in the infrared region, so that an infrared lamp containing quartz glass, which is widely used, cannot be efficiently heated. In addition, since this type of infrared lamp tends to generate stray light with respect to the infrared radiation thermometer, it is more preferable to use a short wavelength lamp having a high absorption efficiency of a silicon wafer.

If the temperature at which film formation on the substrate is started in the vacuum processing chamber is lower than the baking heating temperature in vacuum for removing adsorbed moisture from the substrate, the baking is performed. Then, the substrate must be cooled to a predetermined temperature in a vacuum chamber and the substrate must be adjusted to a predetermined film formation start temperature. In order to realize such a film forming process with high accuracy, a stage having a first infrared radiation thermometer for performing temperature calibration in a temperature calibration chamber, and a stage for performing baking of a substrate in a vacuum are provided. A stage for cooling to a temperature at which a predetermined film formation is started before further starting film formation;
And a second infrared radiation thermometer capable of automatically and accurately measuring the substrate temperature in the cooling stage by using a correction value calculated based on the emissivity obtained by the first infrared radiation thermometer. Required sputtering equipment.

In the case of an apparatus for forming a metal film by sputtering, an infrared ray radiated on a surface opposite to the surface on which the metal film formed on the substrate is observed is reflected. If not, the magnitude of the radiation incident on the infrared radiation thermometer differs depending on the presence or absence of the film, and the apparent infrared emissivity differs, but to the surface of the substrate opposite to the surface observed by the infrared radiation thermometer by the shutter Since the radiated infrared rays are almost reflected, the difference in apparent infrared emissivity before and after the film formation can be significantly reduced.

Further, in the stage for heating or cooling the substrate, the substrate is brought close to the surface opposite to the surface observed by the infrared radiation thermometer through the opening window of the stage and has sufficient wavelength for the measurement wavelength of the infrared radiation thermometer. By disposing a shutter mechanism whose main surface is constituted by a member which is a mirror surface, stray light penetrating the base and entering the infrared radiation thermometer can be blocked.

Further, as means for solving a practical problem in a multi-chamber type film forming apparatus, a vacuum processing chamber provided with means for heating or cooling a substrate to a predetermined set temperature, a vacuum film forming process for the substrate, A vacuum film forming chamber provided with a means for performing the following steps; a transfer chamber provided with the vacuum processing chamber or a transfer robot for transferring the substrate to the vacuum film formation processing chamber; and radiant heat of the substrate in the transfer chamber. A vacuum processing apparatus comprising: an infrared radiation thermometer for measuring the temperature of the infrared radiation thermometer; and a reflector provided to face the substrate and reflecting radiant heat by a member that is a mirror surface with respect to the measurement wavelength of the infrared radiation thermometer. And loading the substrate into a vacuum processing apparatus, moving the substrate to a transfer chamber, then moving the substrate to a vacuum processing chamber and Performing a predetermined vacuum processing on the substrate in a chamber, and thereafter measuring the temperature of the substrate in a transfer chamber, wherein the vacuum processing includes a step of heating or cooling the substrate, a step of cleaning the substrate, A film forming method for forming a thin film on the substrate, wherein a single or a plurality of steps of the vacuum processing are used in combination may be employed.

[0044]

Before performing a predetermined process on the substrate in the vacuum processing chamber, the substrate is heated or cooled to a known temperature in the temperature calibration chamber, and the temperature of the substrate is measured by the first infrared radiation thermometer and the thermocouple. It measures and calculates the correction value of the infrared radiation thermometer, that is, the emissivity based on the measurement result.
Based on the calculation result, the temperature of the substrate in the subsequent vacuum processing chamber is accurately measured by the second and third thermometers. Then, based on the measurement result, the temperature control system is operated to set the temperature of the substrate in the vacuum processing chamber to a predetermined value, and the vacuum processing such as the film forming processing is performed in an accurately controlled temperature state.

In the present invention, arranging 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 an apparatus for forming a metal film by sputtering or CVD, it is very close to forming a metal film by this shutter regardless of the presence or absence of the metal film. Since the infrared emissivity can be obtained, the difference in apparent infrared emissivity before and after film formation can be corrected, and correct temperature control of the substrate based on accurate temperature measurement can be performed. Is to block stray light that penetrates the base and enters the infrared radiation thermometer, thereby preventing measurement errors due to the stray light.

This shutter mechanism is always necessary especially on the thermometer side of the substrate before film formation.

The other functions which cannot be described here will be specifically described in the section of the embodiment.

[0049]

Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 FIG. 1 is a schematic configuration diagram showing one embodiment in which the vacuum processing apparatus of the present invention is applied to a sputtering film forming apparatus. In this embodiment, a typical example in which a silicon wafer is used as a wafer to be formed and an Al thin film is formed thereon by sputtering.

The vacuum processing apparatus 1 of the present invention comprises a wafer temperature calibration chamber 2 having a wafer temperature calibration stage 5, a wafer temperature adjustment chamber 3 having a wafer temperature adjustment stage 6 for heating and cooling a wafer, It comprises three chambers: a stage 7, an Al target 8, and a sputter deposition chamber 4 having a sputter electrode 9. Each of these chambers has a gate valve G
Connected and independent by V1 and GV2. An exhaust system is connected to each of the chambers 2, 3, and 4. On the one hand, a predetermined vacuum state can be maintained, and on the other hand, a predetermined gas is introduced from a gas inlet so that the wafer temperature calibration chamber 2 can be maintained.
Is configured so that the atmosphere can be set to atmospheric pressure by introducing air or nitrogen gas, and the sputter deposition chamber 4 can be set to an environment in which plasma is generated by introducing a sputter gas and generating a predetermined discharge. I have. Further, each stage is provided with a heating and cooling means as described later, and an opening window 19 comprising a through hole for observing radiant infrared rays from the wafer 10 is provided,
Optically coupled through this opening window 19, the first and second
And the third infrared radiation thermometers 11, 14 and 15 are connected, and the wafer 10 on each of the stages 5, 6, and 7 is connected.
Shutters 20, 21, whose main surfaces are composed of members that are sufficiently specular with respect to the measurement wavelength of the infrared radiation thermometer above,
22 are arranged in close proximity.

The wafer temperature calibration stage 5 is provided with a thermocouple 12 for accurately measuring the temperature of the wafer temperature calibration stage 5. Then, the output of the thermocouple 12 and the infrared emissivity of the wafer 10 measured by the first infrared radiation thermometer 11 are input to the arithmetic processing unit of the wafer temperature controller 13,
Means for estimating the infrared emissivity of the wafer 10 in the temperature range to be measured for the wafer 10 as a function of the temperature of the wafer based on the infrared emissivity based on the infrared emissivity;
Observing the temperature of the wafer during vacuum processing by a thermometer, and converting the electric output of the second thermometer into a temperature based on the infrared emissivity determined as a function of the temperature for the wafer. Wafer 1 on stage
Measure the correct temperature of 0. Finally, a command for setting a predetermined stage temperature based on these measurement data is fed back to each of the heating and cooling means of the stage to set and control the temperature of the stage to a predetermined value. Is provided with a wafer temperature controller 13 for managing the temperature.

Next, the function of each chamber will be described. The wafer temperature calibration chamber 2 normally holds the wafer 10 placed on the calibration stage 5 at the same environmental temperature as that of the calibration stage. Has a function of estimating the infrared emissivity of the wafer 10 as a function of the temperature, and obtaining the relationship between the thermometer output specific to the wafer 10 and the temperature.

The wafer temperature adjusting chamber 3 has a temperature adjusting function before transferring the wafer to the next sputter film forming chamber 4, and the sputter film forming chamber 4 has a function of forming a film on the wafer by sputtering.

A specific example in which the temperature of each stage is controlled to maintain the wafer 10 at a predetermined temperature and an Al thin film is sputter-formed on the wafer 10 from the Al target 8 will be described.

First, the wafer 10 is placed in the calibration stage 5 in the wafer temperature calibration chamber 2 placed in a vacuum atmosphere.
Ar gas of 5 Pascal is introduced into the space between the calibration stage 5 and the wafer 10 by a gas introduction mechanism (not shown).
° C, the back surface of the wafer 10 is observed and measured by the first infrared radiation thermometer 11 and the thermocouple 12, and the arithmetic processing unit of the wafer temperature controller 13 uses the infrared radiation rate of the wafer 10 as a function of temperature. Then, the relationship between the wafer temperature and the wafer temperature specific to the wafer 10 is calculated, and a thermometer output-temperature conversion table is created. The details of the emissivity and thermometer output-temperature conversion table will be described later.

Since the temperature of the wafer 10 on each stage can be obtained from the thermometer output-temperature conversion table obtained from the first infrared radiation thermometer 11, the wafer temperature adjustment in a vacuum thereafter is performed. The processing temperature of the wafer 10 on the chamber 3 and the sputter deposition chamber 4 is determined by using a thermometer electric output-temperature conversion table unique to the wafer 10 and the second and third processing temperatures.
The electric outputs from the infrared radiation thermometers 14 and 15 are converted into temperature and read.

The wafer temperature controller 13 also determines on which stage the wafer 10 measured by the calibration stage 5 is being carried and mounted, and is mounted on the stage using the wafer temperature conversion table. The temperature of the wafer 10 is measured.

After the calibration of the emissivity by the first infrared radiation thermometer 11 is completed, the wafer 10 is moved to the gate valve GV.
1 is opened, transported from the calibration chamber 2 to the wafer temperature adjustment chamber 3, and the temperature is measured by the second infrared radiation thermometer 14. The temperature of the stage 6 is adjusted by the wafer temperature controller 13 from the measurement result, and the temperature of the wafer 10 is adjusted to an arbitrary predetermined temperature. In this example, the temperature was set to 100 ° C. Thereafter, the wafer 10 is moved to the gate valve GV2.
Is opened, conveyed to the stage 7 of the sputtering film forming chamber 4 in a vacuum state, and the temperature is measured by the third infrared radiation thermometer 15. Based on the result, the temperature of the stage 7 is adjusted to an arbitrary predetermined temperature. Then, the temperature of the wafer 10 is controlled to an arbitrary predetermined temperature to form a sputter film. In this example, 2
The film was set at 50 ° C. to form an Al film by sputtering. Then, for another wafer other than the wafer 10 not shown, a thermometer electric output-temperature conversion table unique to another wafer other than the wafer 10 is created in the same procedure as in the case of the wafer 10 described above. Used to measure and control the temperature of the wafer.

Although calibration is essentially required for each wafer, when using an infrared radiation thermometer for detecting the wavelength of an opaque region for a material, a metal film on the wafer surface side is used. Since the emissivity does not change irrespective of the presence or absence of the formation, the emissivity can be measured and corrected without using the shutter. Therefore, all the temperature measurements in each chamber in the vacuum processing apparatus are similarly measured without using a shutter.

As a simple means for transferring between the chambers, for example, a transfer mechanism using a heat-resistant belt such as silicone rubber is used.

Next, the outline of the structure of the stage on which the wafer is mounted, the method of heating and cooling, and the method of measuring the emissivity of the wafer will be described with reference to the example of the wafer temperature adjustment stage 6 with reference to FIG.

(1) Structure of Wafer Temperature Adjustment Stage and Heating / Cooling Method:
8, and a structure in which a heat transfer gas flows in a space between the stage 6 and the wafer 10 in a vacuum. Wafer 1
An opening window 19 for measuring the temperature of 0 with the infrared radiation thermometer 14 and a cylinder 16 for guiding infrared light from the wafer to the infrared radiation thermometer and blocking stray light are connected. Window plates 27 and 28 made of a material that transmits infrared rays are attached to both ends. Further, the cylinder 16 itself is heated and cooled so as not to become a source of stray light. In order to further reduce the influence of stray light, the inner wall of the cylinder 16 can be mirror-finished. Further, a shutter 21 is provided. Note that the shutter is
Any structure may be used as long as it has (1) a mirror surface having infrared reflectance, and (2) a device having a function of blocking stray light. For example, a structure that can be opened and closed in synchronization with a wafer temperature measurement timing, or Various configurations can be adopted, such as providing a fixed shutter in one area of the chamber and moving the wafer to a lower portion of the shutter during measurement. The means for bringing the wafer into contact with the stage may be of an electrostatic chuck type. When cooling the wafer, a cooling mechanism may be provided in the stage instead of the heater 18. In this method, since there is no physical contact on the wafer surface side, there is no contamination on the wafer surface side, and the generation of foreign substances can be suppressed to a low level.

(2) Measurement of emissivity: Next, a method of measuring the temperature of a wafer using an infrared radiation thermometer will be described. In this embodiment, the infrared radiation thermometers 11, 14, and 15 are installed at the lower part of each stage to measure the temperature on the back side of the wafer, and stray light from each chamber is incident on the infrared radiation thermometer. A stray light blocking cylinder 16 is provided between the stage and the infrared radiation thermometer so as not to be disturbed. Shutters 20, 21, and 22 made of a member that reflects external light are provided so as to be respectively installed.

Next, in order to prevent the wafer from being adversely affected on the subsequent stages on the calibration stage, it is effective to control the ambient temperature (room temperature) without heating and measure the emissivity. For that purpose, measurement of the emissivity with a high S / N is indispensable. The configuration of the calibration stage that enables accurate measurement of the emissivity with a high S / N ratio at the environmental temperature (room temperature) in the calibration stage will be described below with reference to FIG.

The wafer 10 is held and placed on the calibration stage 5 at an environmental temperature of 20 ° C. by an electrostatic chuck. The inner surface of the stray light blocking cylinder 16 has a mirror surface, and infrared radiation (stray light) which affects the measurement. ) And intrusion. When measuring, a shutter 20 made of a member that reflects infrared light is installed in the vicinity of the wafer 10 on the side opposite to the side observed by the infrared radiation thermometer. The generation of infrared radiation (stray light) that affects the measurement is eliminated. Further, with respect to the infrared radiation from the infrared radiation thermometer 11 itself, the thermometer is cooled and controlled at a low temperature, preferably at 0 ° C. or less. Similarly, the stray light blocking cylinder 16 and the shutter 20 are also controlled to a low temperature, and the stray light due to the infrared radiation can be sufficiently neglected as compared with the infrared radiation from the wafer when the wafer 10 is at an ambient temperature (room temperature: usually around 20 ° C.). So that it is less.

Further, when high-precision temperature measurement and control are required, for example, in the case of tungsten-CVD, the measurement temperature of the infrared emissivity is made equal to the CVD temperature in order to control the deposition rate with high accuracy. The thermometer correction was realized, and the temperature was controlled. At a temperature of 200 ° C. or more, a film thickness variation of ± 1% was obtained.

Embodiment 2 FIG. Another embodiment in which an aluminum film is formed on a wafer 10 by sputtering using the sputtering apparatus 1 of FIG. 4 will be described.

The temperature of the wafer 10 is measured by the thermocouple 12 in the temperature calibration chamber 2, and the emissivity of the infrared radiation thermometer 11 is measured based on the measured temperature to correct the emissivity specific to the wafer 10 and the output voltage of the thermometer. And the converted value of the temperature
Using the converted value of the thermometer output voltage and the temperature, the temperature is measured in the wafer temperature adjustment chamber 3 and the sputter film formation chamber 4. Next, the wafer 10 is transferred to the load lock chamber 23, evacuated, and then transferred to the wafer temperature adjustment chamber 3. The wafer 10 conveyed to the wafer temperature adjustment chamber 3 is heated by the lamp heater 25, at which time the temperature is measured by the infrared radiation thermometer 14 and is controlled to 400 ° C. Next, it is transported to the sputter deposition chamber 4. The wafer 10 is sputtered in the sputter deposition chamber 4 according to a temperature profile as shown in FIG. The target 8 had a composition of 1% Si-3% Cu-Al.

The wafer temperature controller 13 also determines on which stage the wafer 10 measured by the calibration stage 5 is being carried and mounted, and is mounted on the stage using the wafer temperature conversion table. The temperature of the wafer 10 is measured. Then, the temperature of the stage 6 is adjusted by the wafer temperature controller 13 from the temperature measurement results at each stage, and the temperature of the wafer 10 is adjusted to an arbitrary predetermined temperature.

First, the temperature of the wafer 10 is set to 230 ° C.
Then, the first sputter film is formed to a film thickness of about several hundred degrees, the sputter is stopped once, and the wafer is transferred to the wafer temperature adjusting chamber 3. In the wafer temperature adjustment chamber 3, the temperature of the wafer 10 is controlled to be 300 ° C. by a lamp heater, and the temperature of the Al
The crystal grains of the film are grown to improve the orientation and the like. Next,
The wafer is transported again to the sputter deposition chamber 4 and the temperature of the wafer is set to about 400 ° C., and then the second sputter deposition is restarted to deposit the film to a thickness of about 1 μm. As a result, an Al sputtered film having large crystal grains and good orientation can be obtained. Immediately after the end of sputtering, the wafer is placed in the unload chamber 2
4 and rapidly cooled to about 50 ° C. Thereby, precipitation of Si and Cu in the Al sputtered film could be suppressed.

In the above embodiment, an example was described in which an Al thin film was formed on the wafer surface by sputtering. However, since the temperature of the wafer can be controlled with high precision via a stage, crystallinity with good reproducibility within the wafer can be obtained. As a result, a film having excellent quality could be achieved. For example, when heating a thin film having a thickness of several hundred degrees at a heating temperature of 350 ° C. or higher, no improvement in crystallinity was obtained. Therefore, such a film forming method cannot be industrially realized without the present invention, which can know an accurate temperature.

It should be noted that the vacuum processing apparatus of the present invention is not limited to the above-mentioned spatter apparatus, and may be a CVD (Chemical Vapor Depo)
It is needless to say that the present invention can be applied to a film forming apparatus based on sition).

For example, it is effective when a silicon wafer is used as a base and a tungsten film is formed on the wafer by a known method by CVD.

In any of these types of film forming apparatuses, the accuracy of wafer temperature control affects the quality of a film to be formed, and therefore, the film forming apparatus of the present invention can sufficiently cope with this.

The vacuum processing chamber can be realized by using a vacuum processing chamber as the film forming processing chamber as in the above embodiment. However, this vacuum processing chamber can be replaced by a dry etching process such as plasma etching. And the temperature control of the wafer to be etched can be easily realized as in the above embodiment.

Embodiment 3 FIG. A measurement example of the wafer temperature during the sputter deposition and the lamp heating when the vacuum processing apparatus of the second embodiment is used for the sputter deposition will be described below.

FIG. 6 shows a change over time in the temperature of the wafer during the film formation by sputtering. It can be seen that changing the sputtering power causes a difference in the film forming temperature.

FIG. 7 shows a measurement example when the temperature of the wafer 10 is controlled to be heated by lamp heating in the wafer temperature adjustment chamber 3. As shown in FIG. 8, a stage lamp for heating the lamp is provided with a heating lamp 25 above the wafer, and a shutter 21 is arranged between the wafer and the lamp so as to be close to the upper portion of the wafer only when measuring the temperature. The thermometer 14 is installed below the stage. Further, the shutter 21 is configured to be driven to open and close in synchronization with the temperature measurement timing of the wafer, or a fixed shutter is provided in one region of the chamber,
Various configurations such as a mechanism for moving the wafer to the lower part of the shutter at the time of measurement can be adopted. The broken line in FIG. 7 indicates a value in which infrared light from the lamp is incident on the infrared radiation thermometer as stray light when the shutter 21 is not installed on the wafer 10 when the lamp is heated. Absent. Therefore, when the shutter 21 is inserted on the wafer 10, stray light is removed as shown by the solid line in the figure, and the measured value is reduced. This value is the actual wafer temperature. Thus, in the case of lamp heating, the shutter 21 has an effect of removing stray light from the lamp. At the time of lamp heating, the shutter 21 is installed at a location away from the wafer, and does not hinder lamp heating. FIGS. 9 and 10 show a method of controlling the temperature of the wafer at the time of lamp heating, in which the wafer temperature T ₀ before the start of heating and the temperature T ₁ after a known time t1 has elapsed since the start of heating are represented by infrared radiation temperature. The temperature is measured by a meter and the heating rate up to that is determined. Thereafter, assuming that the heating rate is constant, the remaining heating time t2 for heating to a desired heating temperature (set temperature; T _S ) is determined. And measuring the temperature T ₂ after the completion of heating. As a result, as shown in FIG. 10, control can be performed with an accuracy of ± 2.5 ° C. with respect to the settings of 300 ° C. and 400 ° C.

Embodiment 4 FIG. FIG. 1 shows a method of correcting the emissivity, a method of preparing a thermometer output-temperature conversion table, and a method of measuring the temperature of a wafer when emissivity is measured by a calibration stage
This will be described with reference to FIGS. 1 to 14 and Tables 1 to 5.

FIG. 12 is a configuration diagram of a conventionally used infrared radiation thermometer. The output from the infrared radiation thermometer 30 is proportional to the radiation energy, and has a non-linear relationship with the actual temperature. For this purpose, a linearizer 38 for linearizing the output from the infrared radiation thermometer 30 is required. Data for linearization processing by the linearizer can be obtained by numerical calculation from a well-known blackbody radiation equation. Table 1 summarizes the relationship between the output signal voltage of the infrared radiation thermometer and the measured temperature based on the results of such calculations.

[0082]

[Table 1]

An amplifier 36 is provided before the linearizer 38, and the amplifier 36 has a gain adjusting function 37. Emissivity is a measure of the ease with which an object can emit radiation according to temperature. For example, for an object having an emissivity of 1, the temperature can be measured by setting the gain of the amplifier to 1.

If the emissivity is 0.5, the temperature can be measured by setting the gain of the amplifier to 2. That is, the emissivity is adjusted to the overall sensitivity before performing linearization.

In the case where the infrared emissivity changes with the temperature, it is necessary to change the gain of the amplifier 36 in FIG. 12 so as to follow the temperature. Examples according to the present invention will be described in more detail.

FIG. 11 shows an example in which signal processing of the thermometer shown in FIG. 12 is performed using a computer, and linearization processing is also performed by digital calculation.

An analog signal from the infrared radiation thermometer 30 is converted into a digital signal by the A / D converter 31 and is taken into the computer 32. The result of the arithmetic processing is displayed or recorded via a display 33, a floppy disk 34 and an analog signal for a recorder via a D / A converter 35.

Next, the temperature measurement will be described with reference to the flowchart of FIG. 13 and FIG.

First, when the emissivity of the wafer is measured at a known temperature by the calibration stage and the measured temperature is measured at, for example, T ₀ , the emissivity = ε ₀ is obtained. Then emissivity at Tmax, in semiconductors such as Si wafer, have been found to be constant for metallizing becomes a high temperature above 500 ° C., converges to epsilon _max. The relationship between the wafer temperature and the infrared emissivity is determined by the computer 32 as a temperature function ε (T) by a linear interpolation operation. Table 2 shows an example of this.
R>.

[0090]

[Table 2]

Based on the emissivity characteristic of the wafer, the conversion table of the thermometer output and the temperature specific to the wafer is stored in the computer 32.
Create by This conversion table is created as a linear conversion table by calculating the emissivity in increments of 0.01 from the theory of blackbody radiation. For the emissivity of the wafer, linearization data is picked up from the table at every wafer temperature of 1.0 ° C., and a final conversion table specific to the wafer is made as shown in Table 5. In the measurement of the wafer in the vacuum processing apparatus 1, the temperature is measured by sequentially referring to the conversion table.

Next, a specific description will be given, with reference to Tables 2, 3, 4, and 5, of the arithmetic processing for creating the thermometer output-temperature conversion table specific to the wafer shown in Table 5. However, the numerical values are virtual.

[0093]

[Table 3]

[0094]

[Table 4]

[0095]

[Table 5]

First, a method of calculating the emissivity will be described. FIG. 14 shows the results of separately measuring the temperature change of the emissivity of the wafer whose temperature is to be measured. For example, the emissivity of the wafer is measured at 150 ° C.,
When 0.3 was obtained, linear interpolation was performed between the measured emissivity of 0.3 at 150 ° C. and the emissivity of 0.5 (500 ° C.) which becomes constant at a high temperature, and is shown in Table 2. Such an emissivity can be obtained. Next, the relationship between the output of the thermometer of the wafer and the temperature is calculated from the relationship between the emissivity and the output of the thermometer of the black body and the temperature, and the emissivity shown in Tables 3 and 4 is, for example, 0.30 and 0.31, respectively. The relationship between the thermometer output and the converted temperature at the time of can be obtained. When the emissivity is 0.30 or 0.31, the wafer has a voltage value of 0.3 at the output of the infrared radiation thermometer that gives the same measurement temperature as compared with the black body shown in Table 1.
It is 0.31, 0.3 times. This is natural from the definition of object radiation.

Next, the arithmetic processing inside the computer will be described below.

From Table 2, it is found that the emissivity of the wafer should be 0.3 in the section from 150 ° C. to 151 ° C.
The output voltage of the thermometer giving 150 ° C. is 0.51 from Table 3.
0V. Also, from Table 2, at 152 ° C., the emissivity is 0.3.
From Table 10, it can be seen from Table 4 that the output voltage of the thermometer giving 152 ° C. is 0.530V.

The above operation is performed within the temperature range to be measured. For example, as an example, as shown in Table 5, the relationship between the output voltage of the radiation thermometer and the measured temperature is newly summarized in a table.

If the conversion between the thermometer output voltage and the temperature as shown in Table 5 is performed within the temperature range to be measured, as shown in FIG. 4, even for a semiconductor wafer whose emissivity greatly changes, as shown in FIG. By performing emissivity measurement only at one low temperature close to the temperature, accurate measurement can be performed over the entire temperature range to be measured.

Embodiment 5 FIG. Hereinafter, a method for measuring the emissivity of a Si wafer as a wafer will be described with reference to FIG.

FIG. 15 is a conceptual diagram showing a method for measuring the emissivity of a wafer. The wafer 10 is mounted on the wafer temperature calibration stage 5. A mirror reflector 40 is provided above the wafer 10. The specular reflector 40 must have a sufficiently high reflectivity in the intended measurement wavelength range.

A beam splitter 41 is provided below the wafer temperature calibration stage 5. Reference light generator 42
In this example, the output light having a wavelength of about 10 μm as a main component can be obtained by appropriately using a filter.
3 passes through the beam splitter 41 and enters the wafer 10. The reflected light 44 from the wafer 10 is bent by the beam splitter 41 and enters a photodetector 45.

Light radiated or transmitted above the wafer 10 is reflected by the specular reflector 40, and all of the light is returned to the wafer 10.

In general, the emissivity is equal to the absorptivity α when the incident light intensity is Io, the transmitted light intensity It, and the reflected light intensity Ir are known, and is expressed by the following equation.

Α = (Io−It−Ir) / Io In the example shown in FIG. 14, the transmitted light I
t = 0. Therefore, the absorptance or the emissivity can be calculated by knowing the incident light intensity Io and the reflected light intensity Ir to the wafer 10. In order to apply the emissivity obtained in this way to, for example, a wafer such as the wafer 10 before vapor deposition, the temperature is measured from, for example, the back surface by an infrared radiation thermometer, and at that time, a mirror surface is applied to the front side of the wafer 10. Install a reflector. Since the metal film itself is the specular reflector during or after the deposition of the metal film, the specular reflector 40 is unnecessary.

Embodiment 6 FIG. Sixth Embodiment A sixth embodiment of the present invention will be described with reference to FIGS.

FIG. 16 is a schematic configuration diagram (plan view) in which the vacuum processing apparatus of the present invention is applied to a sputtering film forming apparatus. In this embodiment, a silicon (Si) wafer (hereinafter, referred to as a wafer) is used as a film formation target, and an Al or Al alloy thin film (hereinafter, an Al thin film or an Al film) is formed thereon by sputtering. explain. The vacuum processing apparatus 50 of the present invention includes a wafer load chamber 51 and an unload chamber 5.
2, a vacuum bake chamber 53 as each vacuum processing chamber for performing vacuum processing, and a sputter etch chamber 54 for removing a natural oxide film or the like on the surface which causes wiring continuity failure prior to the formation of the Al film. Film forming chamber 55 for forming Al and Al films
And a transfer chamber 57 provided with a transfer mechanism (for example, an articulated transfer robot) for transferring the wafer 10 to each vacuum processing chamber and transferring the wafer 10 back from each vacuum processing chamber after each vacuum processing. Configuration. Each of the vacuum processing chamber and the transfer chamber is provided with a gate valve 58, 59, 6 respectively.
0, 61, and 62 are independent. Also,
Each chamber is connected to an exhaust system (not shown) and can be maintained in a predetermined vacuum state. An infrared lamp heater (not shown) for heating the wafer is disposed in the vacuum bake chamber 53, and a predetermined gas is introduced from a gas inlet (not shown) into the sputter etch chamber 54 and the sputter film formation chamber 55. It is configured so that it can be set to an environment where plasma is generated by a predetermined discharge. The sputter etching chamber 54 and the sputter film forming chamber 55 are provided with heating means. In the configuration of the present embodiment, the temperature is not measured during the processing in these chambers, but the heating means is set under constant heating conditions. The temperature measurement in the transfer chamber 57 is performed to measure the temperature of the wafer before and after the wafer is put into the vacuum film formation chamber. Furthermore, the load chamber 51 and the unload chamber 52
A loading mechanism (not shown) for introducing a gas (for example, nitrogen gas or air) for returning both chambers from the vacuum state to the atmospheric pressure for loading and unloading the wafer, and doors 63 and 64 for loading and unloading, respectively. In preparation.

FIG. 17 shows the vacuum processing apparatus 50 shown in FIG.
5 is a cross-sectional view taken along line AA ′ of FIG.

In this embodiment, the position of the transfer chamber 57 where the infrared radiation thermometer 65 is installed is a temperature measurement position, and the temperature measurement position is fixed to the transfer chamber 57. FIG.
Shows the optical system at the temperature measurement position in more detail.

As shown in FIG. 18, an opening window 67 for measuring the temperature of the wafer 10 with an infrared radiation thermometer 65 and a stray light blocking cylinder 68 are connected to the temperature measuring optical path 66. It has a structure in which it is heated and cooled with water so that it does not become a source of stray light. In order to further reduce the influence of the stray light, it is possible to cool the inner wall of the cylinder 68 and then perform a black body treatment. The infrared radiation thermometer 65 is installed in the atmosphere.

For this purpose, the optical path 66 must pass through the boundary between the atmosphere and vacuum. The site 67 is an observation window for this purpose, and a window plate 69 for separating atmospheric pressure and vacuum is installed in the observation window 67. The window plate 69 is made of a material that efficiently transmits infrared rays, for example, barium fluoride, calcium fluoride, ZnSe (zinc selenium), or the like. Since the window plate 69 must withstand the atmospheric pressure, it is common to use a window plate having a thickness of about 5 mm to secure the strength. Further, in order to prevent stray light from the periphery from entering as noise detected by the infrared radiation thermometer 65, the wafer 1 is placed on the front side 10-1 of the wafer 10 at the temperature measurement position.
The reflector 70 is set so that the reflection surface faces the wafer 10 so as to approach 0 to about 1 to 3 mm. That is, the size of the reflector 70 is such that infrared radiation from the wafer surface can be reflected by the mirror surface of the reflector 70 and sufficiently incident on the region of the observation optical path 66, and the reflector 70 and the front side 10 of the wafer can be used. -1 is close enough that stray light does not enter as noise detected by the infrared radiation thermometer 65.

The reflector 70 has (1) a specular infrared reflectance. (2) Any structure and material may be used as long as it has a stray light blocking function.

FIG. 19 shows an example of a process flow performed in this embodiment.

The wafer introduced into the vacuum from the load chamber 51 is degassed and baked in the vacuum bake chamber 53, and a sputter etch chamber 54 is used to remove a natural oxide film on the wafer surface. At 55, an Al film is formed on the wafer surface side 10-1 by a sputtering method, and is taken out from the unload chamber 52 to the atmosphere. In order to transfer the wafer to each of the vacuum processing chambers, the wafer must be transferred to and from each of the vacuum processing chambers.
At this time, that is, before and after each vacuum processing, the temperature of the wafer is measured at the temperature measurement position provided in the transfer chamber 57.

The door 63 is opened in the load chamber 51 under the atmospheric pressure, and one or a plurality of wafers are introduced (Step 81).
Thereafter, the load chamber 51 is evacuated to a predetermined pressure.
Thereafter, the gate valve 58 is opened, and the transfer robot 72
The second wafer is taken into the transfer chamber, transferred to the temperature measurement position, and subjected to temperature measurement (process 82).

The apparent emissivity from the wafer varies depending on the type of the semiconductor product and the structure and type of the thin film formed in the manufacturing process, that is, the process performed before the main sputtering film forming process. Different. Therefore, the present infrared radiation thermometer has one
The emissivity is calibrated in advance for each sheet. Incidentally, the case where the emissivity = 1 is a complete blackbody. Si wafers have a relatively low apparent emissivity (0.2-0.5). Since the Si wafer transmits infrared light in a wide range of infrared wavelengths, the infrared light transmitted from the front side 10-1 as stray light when the metal film (Al film) is not yet formed on the wafer as infrared light. The light enters the radiation thermometer and becomes a noise component. In the present invention, the reflector 70 is brought close to the wafer, and the stray light blocking cylinder 68 is closed.
The stray light does not enter the infrared radiation thermometer, and stable temperature measurement without stray light noise becomes possible. Furthermore, since the reflector 70 reflects the infrared light from the front side 10-1 of the wafer to the back side 10-2, it can apparently increase the emissivity of the back side of the wafer.
Temperature can be measured by the noise ratio.

Next, the wafer is transferred to the vacuum bake chamber 53, and the wafer is heated in the vacuum bake chamber 53 to perform degassing bake (Step 83), and then again to the transfer chamber 57.
And the temperature of the wafer after vacuum baking is measured again in the same manner as described above (process 84). The temperature measured at this time is the wafer temperature before the next sputter etching process. Then, after the wafer is transferred to the sputter etch chamber and subjected to the sputter etch process (process 85), the wafer is again transferred to the transfer chamber 57 and the temperature of the wafer after the sputter etch is measured again in the same manner as described above (process 86). ). This temperature is set as the wafer temperature before the subsequent Al film is formed by sputtering.

Next, the wafer is transported to the sputter deposition chamber 55 to form an Al film (Step 87), and then the wafer is transported back to the transport chamber 57 again. Is measured in the same manner as described above (step 88).

After the Al metal film is formed on the surface of the Si wafer, the infrared light radiated from the front side 10-1 of the wafer is reflected by the formed Al film and transmitted through the wafer to the back side 10-2 of the wafer. Since the radiated light is added to the radiated light from the original wafer back surface 10-2, the apparent emissivity from the wafer back surface 10-2 is significantly increased. Therefore, in the temperature measurement by the conventional infrared radiation thermometer, the emissivity calibrated before the film forming process cannot be used by the subsequent film forming process. However, according to the present invention, even if the wafer is not formed with Al, since the reflector 70 exhibits a reflection characteristic equivalent to the Al metal film to be formed on the front side 10-1 of the wafer, Al metal is formed. In all steps of the process flow shown in FIG. 19 before and after the film formation, the temperature can be measured without changing the emissivity of the wafer originally calibrated.

As described above, since the Al film is a very good reflector, it indicates that the emissivity is very low (about 0.01 to 0.15). That is, the emissivity on the front side of the wafer becomes very small after the formation of the Al film, so that it is hardly possible to obtain infrared radiation sufficient for temperature measurement. Therefore, contrary to the present invention, the wafer front side 10
When the temperature is measured from -1 using an infrared radiation thermometer, the emissivity before and after the Al metal film is formed changes more greatly. Can no longer be used. Moreover, in this case, the apparent emissivity changes irrespective of whether or not the reflector 70 is used, so that it is very difficult to measure the temperature on the surface on which the film is formed. On the other hand, in the present invention, the measurement is performed from the back surface of the wafer as described above, and this problem is solved by using the reflector 70.

After the temperature measurement after the formation of the Al film, the wafer is transferred to the unload chamber 52, and thereafter, a gas, for example, air or nitrogen gas, is introduced only into the unload chamber 52 to bring the unload chamber 52 to atmospheric pressure. Thereafter, the door 64 is opened to take out the wafer from the vacuum processing apparatus 50 (process 89). Then, the temperature measurement and vacuum processing are repeatedly performed on the next wafer in the manner described above.

However, the process flow shown in the present invention is not limited to the above-described one embodiment, but can be performed in various forms.
That is, in the case of forming a laminated wiring film structure, the present invention can be easily applied to one or more film forming processing chambers in addition to the flow shown in FIG.

In addition to the process shown in FIG. 19, the vacuum process may be a cooling process for cooling the wafer to a predetermined temperature after a heating process, a sputter etch cleaning process, a sputter film forming process, or the like. The present invention is applicable without any problem.

Further, in the above-described embodiment, the description has been given by taking the example of the Al sputter film formation. The present invention can be applied without departing from the gist of the present invention.

The present invention also relates to a so-called glass wafer containing, as a main component, a material exhibiting a property of being transparent or translucent to infrared wavelengths, such as silicon oxide or aluminum oxide, in addition to the silicon wafer. The invention is also applicable to CaAs (gallium arsenide) wafers and the like.

In the above embodiment, the measured temperature in the transfer chamber 57 is treated as the temperature before and after the vacuum processing as it is. However, the heat radiation speed varies depending on the speed of the transfer robot and the emissivity of the wafer itself. Therefore, strictly speaking, the measured temperature at the temperature measurement position in the transfer chamber 57 is different from the start or end temperature of each vacuum processing. For the process in which this difference in temperature is problematic, by performing temperature measurement for a certain time at the temperature measurement position of the transfer chamber, calculating the heat release rate, and extrapolating each vacuum processing start or end temperature from the value. Further highly accurate temperature measurement is possible.

In the above embodiment, the surface of the Si wafer is
Although an example in which a thin film is formed by sputtering has been described above, since high-precision wafer temperature measurement enables early detection of fluctuations in wafer temperature that cause a decrease in yield, a high-quality film is finally formed. High yield was achieved.

[0129]

As described above, according to the present invention, it is possible to accurately measure and control the temperature of a substrate in a vacuum, and realize a vacuum processing apparatus capable of accurately controlling the temperature of the substrate. In addition, by applying the method to a film forming apparatus, it is possible to easily control the temperature before and after the film formation that requires accurate temperature control and during the film formation, so that a high quality film can be formed.

Further, according to the present invention, a vacuum processing apparatus capable of accurately controlling the temperature of a substrate is realized, particularly in a multi-processing type vacuum processing apparatus, and the formation of a high-quality thin film can be continuously controlled. Thus, the final product defect rate can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a partial cross-section of a vacuum processing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional configuration diagram illustrating an example of a wafer temperature adjustment stage.

FIG. 3 is a schematic cross-sectional configuration diagram illustrating an example of a calibration stage.

FIG. 4 is a schematic configuration diagram of a vacuum processing apparatus showing another embodiment of the present invention.

FIG. 5 is an explanatory diagram showing one temperature profile during film formation.

FIG. 6 is a diagram showing an example of temperature rise characteristics measurement during Al sputtering.

FIG. 7 is a diagram showing an example of wafer temperature measurement by lamp heater heating.

FIG. 8 is a schematic sectional configuration diagram of a lamp heating stage.

FIG. 9 is a diagram showing a method of controlling a wafer temperature by lamp heating.

FIG. 10 is a diagram showing a temperature at the end of heating with respect to a set heating temperature.

FIG. 11 is a schematic configuration diagram of an infrared radiation thermometer of the present invention.

FIG. 12 is a schematic configuration diagram of a conventional infrared radiation thermometer.

FIG. 13 is a flow sheet for emissivity measurement and creation of a thermometer output conversion table.

FIG. 14 is a view showing the emissivity measurement result of a wafer.

FIG. 15 is a configuration diagram of an apparatus including a means for calibrating the emissivity of a wafer according to an embodiment of the present invention.

FIG. 16 is a plan view for explaining an embodiment of the vacuum processing apparatus according to the present invention.

FIG. 17 is a diagram illustrating a cross-sectional structure taken along line AA ′ of the vacuum processing apparatus of FIG. 16;

FIG. 18 is a diagram illustrating an optical system for measuring a wafer temperature provided in a transfer chamber of the vacuum processing apparatus according to the present invention.

FIG. 19 is a view for explaining an example of a vacuum processing process flow when the vacuum processing apparatus according to the present invention is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Vacuum processing apparatus, 2 ... Wafer temperature calibration chamber, 3 ... Wafer temperature adjustment chamber, 4 ... Sputter deposition chamber, 5 ... Wafer temperature calibration stage, 6 ... Wafer temperature adjustment stage, 7, 7-1 ... Sputter stage, Reference numeral 8: Target, 9: Sputter electrode, 10: Base (wafer), 10-1: Wafer front side (film formation surface of metal film (Al etc.)), 10-2: Wafer back side, 11, 14, 15 ... Infrared radiation Thermometer, 13: base temperature controller, 16: stray light blocking cylinder, 18: heat block internal heater, 19: opening window, 20-22: shutter, 23: load lock chamber, 24: unload chamber, 25: lamp Heater 27 lower window plate 28 upper window plate 40 specular reflector 41 beam splitter 42 reference infrared light generator for calibration 43 reference incident light 4 ... reflection light, 45 ... reflection infrared light detector, 50 ... multi-chamber type sputter device, 51 ... load chamber, 52 ... unload chamber, 53 ... vacuum bake chamber, 54 ... sputter etch chamber, 55 ... sputter chamber, 57 ... Transfer chamber, 58-62 ... Gate valve, 63 ... Door for wafer loading, 64 ... Door for wafer unloading, 65 ... Infrared radiation thermometer, 66 ... Optical path for infrared radiation thermometer. 67: peep window between air and vacuum; 68: cylinder for blocking stray light; 69: window material for infrared light path separating air and vacuum; 70: reflector; 71: wall of vacuum chamber; 72: transfer robot;

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI H01L 21/66 H01L 21/66 T // H01L 21/203 21/203 Z (72) Inventor Susumu Tsutake Takeshi Totsuka, Yokohama-shi, Kanagawa 292, Yoshida-cho, Ward, Tokyo Hitachi, Ltd. Production Technology Research Laboratory (72) Inventor Eisuke Nishitani 292, Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa, Japan Hitachi, Ltd. Production Technology Research Laboratory (72) Inventor Satoshi Kishimoto Kanagawa, Japan 292, Yoshida-cho, Totsuka-ku, Yokohama, Japan In-house Research Laboratory of Hitachi, Ltd. (72) Inventor: Tokio Kato 5-2-1, Josuihoncho, Kodaira-shi, Tokyo Judgment: Semiconductor Design & Development Center, Hitachi, Ltd. Government Naoyuki Miyazawa (56) References JP-A-3-232968 (JP, A) JP-A-59-181622 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C23C 14 / 00-16/58 B01J 19/08 G01J 5/00 H01L 21/203-21/31 H01L 21/66

Claims (15)

(57) [Claims] 1. The method according to claim 1, wherein the substrate is controlled at an ambient temperature and an infrared emissivity is controlled.
Temperature calibration stage for measuring; measuring radiant heat of substrate
A first infrared radiation thermometer for determining;
Radiation from the output of the thermometer based on the known temperature of the substrate
The emissivity was determined, and the first infrared radiation thermometer was used.
Infrared sensitivity correction value to display body temperature correctly
Means for calculating the same; the same or different base as the stage
The stage on which the body is placed and the substrate
Means for heating or cooling the substrate and applying a vacuum treatment to the substrate
Vacuum processing chamber with means; radiant heat of the substrate
A second infrared radiation thermometer for measuring the infrared radiation;
Determined by the temperature calibration chamber from the output of the X-ray radiation thermometer
It is placed in the vacuum processing chamber based on the infrared sensitivity correction value.
Means for calculating the true temperature of the substrate;
Placed in close proximity to the substrate on the
A member whose surface is sufficiently mirror-
The vacuum processing apparatus equipped with the formed shutter mechanism
A method for measuring the temperature of a substrate, the method comprising:
A method for calculating the infrared sensitivity correction value of the infrared radiation thermometer of 1.
The stage knows the infrared emissivity of the substrate, and changes the emissivity of the substrate.
Determined as a function of temperature, the emissivity is used to calculate the radiance of the substrate.
Create an output and temperature conversion table and use this table
Infrared radiation thermometer characterized by performing temperature measurement by
Method for measuring the temperature of a semiconductor substrate. Wherein interpolated from the values of the emissivity between the infrared emissivity at the temperature emissivity which is different for two or more of the substrate, according to claim 1, characterized in that the determination as a function of temperature
4. A method for measuring the temperature of a semiconductor substrate by using an infrared radiation thermometer according to item 1. The infrared emissivity in claim 3, wherein the different temperatures, subjected to emissivity measurements at a temperature of at least one certain point of the object, also, the emissivity at a temperature higher than the emissivity measured temperature The method for measuring the temperature of a semiconductor substrate by an infrared radiation thermometer according to claim 2 , wherein the temperature is determined in advance. 4. The method according to claim 1, wherein the temperature of the substrate is controlled to an ambient temperature, and the infrared emissivity is controlled.
Temperature calibration stage for measuring; measuring radiant heat of substrate
A first infrared radiation thermometer for determining;
Radiation from the output of the thermometer based on the known temperature of the substrate
The emissivity was determined, and the first infrared radiation thermometer was used.
Infrared sensitivity correction value to display body temperature correctly
Means for calculating the same; the same or different base as the stage
The stage on which the body is placed and the substrate
Means for heating or cooling the substrate and applying a vacuum treatment to the substrate
Vacuum processing chamber with means; radiant heat of the substrate
A second infrared radiation thermometer for measuring the infrared radiation;
Determined by the temperature calibration chamber from the output of the X-ray radiation thermometer
It is placed in the vacuum processing chamber based on the infrared sensitivity correction value.
Means for calculating the true temperature of the substrate;
Placed in close proximity to the substrate on the
A member whose surface is sufficiently mirror-
A vacuum mechanism.
Chamber is configured to perform a processing for a plurality of substrates having a plurality, temperature measurement when the N-th base is subjected to predetermined processing in the M-th vacuum processing chamber, the operation in advance determined for the N-th base A vacuum processing apparatus characterized in that an electric output of a thermometer provided in an M-th vacuum processing chamber is converted into a temperature based on the emissivity as a function of the temperature determined by the estimation by E. 5. A vacuum processing chamber having means for heating or cooling a substrate to a predetermined set temperature, a vacuum etching chamber having means for performing vacuum etching on said substrate, and said vacuum processing chamber or said vacuum processing chamber. a transport chamber having a transport mechanism for transporting said substrate in an etching process chamber, and at least one infrared pyrometer for measuring the radiation heat of the substrate conveying the chamber, to measure the wavelength of the infrared radiation thermometer the vacuum processing apparatus characterized by having a reflector provided opposite to the substrate for reflecting radiant heat in member are mirror Te. Wherein said infrared radiation thermometer provided on the opposite side with respect to surface to be vacuum processing of the substrate, wherein the reflector before
The vacuum processing apparatus according to claim 5, characterized in that provided in the direction opposite to the surface to be vacuum treatment of the serial base. A plurality of vacuum processing chamber of claim 7 performs vacuum processing on a substrate, a vacuum processing apparatus of a multi-chamber system in which a transport chamber having a transfer mechanism for transferring the substrate to the vacuum processing chamber, said At least one infrared radiation thermometer for measuring radiant heat of the substrate in the transfer chamber, and facing the substrate for reflecting radiant heat from the substrate formed of a member having a mirror surface with respect to the measurement wavelength of the infrared radiation thermometer; A multi-chamber type vacuum processing apparatus characterized by having a reflector provided as follows. Wherein said infrared radiation thermometer provided on the opposite side with respect to surface to be vacuum processing of the substrate, wherein the reflector before
The vacuum processing apparatus according to claim 7, characterized in that provided in the direction opposite to the surface to be vacuum treatment of the serial base. 9. A vacuum processing apparatus according to claim 5,
A method of forming a thin film on a substrate using
To the transfer chamber, and then the substrate is vacuum-processed.
Move to the chamber and place the substrate in the vacuum processing chamber.
Perform a constant vacuum process, subject the substrate to a cleaning process,
After subjecting the substrate to a process of forming a thin film, the substrate is
And a step of moving to the transfer chamber.
Before or after applying the treatment,
A film forming method characterized by measuring a temperature in a bath. 10. The film forming method according to claim 9 , wherein the temperature inside the transfer chamber is measured using an infrared radiation thermometer. 11. During the temperature measurement in the conveying chamber,
Claims reflector for reflecting radiant heat from the configured base in member is a mirror surface with respect to the measurement wavelength of the infrared radiation thermometer, characterized in that provided opposite the <br/> base
10. The film forming method according to item 9 . 12. A vacuum processing apparatus according to claim 5, wherein
A film forming method for forming a thin film on a substrate was used to load the substrate to move the substrate body to the first vacuum processing chamber, heating the pre-Symbol substrate with a first vacuum processing chamber, Previous
The serial base moved to the transfer chamber from the first vacuum processing chamber, and temperature measuring said substrate within the transfer chamber, before
Move the serial base to a second vacuum processing chamber is subjected to an etching treatment of the substrate with a second vacuum processing chamber, moving the <br/> substrate to the transfer chamber inside the said substrate transportable <br A film forming method characterized in that a temperature is measured in a transport chamber. 13. The film forming method according to claim 12 , wherein the temperature inside the transfer chamber is measured using an infrared radiation thermometer. 14. During the temperature measurement in the conveying chamber,
Claims reflector for reflecting radiant heat from the configured base in member is a mirror surface with respect to the measurement wavelength of the infrared radiation thermometer, characterized in that provided opposite the <br/> base
13. The film forming method according to item 12 . 15. calculating the temperature change of the transport time of the substrate, film forming method according to claim 9 or 12, characterized in that to calculate the temperature of the substrate at the start or end of the vacuum treatment.