TW202240136A - Temperature measurement method, temperature measurement device, and thin film formation method - Google Patents

Abstract

In the temperature measurement method of this invention, a temperature measurement substrate, on which a phase-change film a physical quantity of which changes due to a change in the arrival temperature is laminated, is subjected to a heat treatment, after the temperature measurement substrate has been subjected to heat treatment, the physical quantity of the phase-change film is measured to obtain a measured physical quantity, and the temperature and temperature distribution of the temperature measurement substrate in the heat treatment of the temperature measurement substrate are obtained on the basis of the measured physical quantity and a predetermined relationship between the physical quantity and the temperature.

Description

Temperature measuring method, temperature measuring device, and thin film forming method

The present invention relates to a technique suitable for use in a temperature measuring method, a temperature measuring device, and a thin film forming method. This case claims priority based on Japanese Patent Application No. 2021-014575 filed in Japan on February 1, 2021, and the contents thereof are incorporated herein.

In the manufacturing process of display devices such as semiconductor devices, liquid crystal displays, organic EL (electroluminescence, electroluminescence) displays, FPD (flat panel display, flat panel display), etc., it is necessary to measure the temperature of the substrate. The previous substrate temperature measurement was performed by manufacturing and using a measurement device that embedded a thermocouple or a thermistor in a substrate such as a silicon wafer, or attached a thermocouple or a thermistor to a substrate, etc. made.

Although these methods can measure the temperature of the substrate in real time, there are problems such as poor workability: there are few measurement points, or the internal pressure of a vacuum device or the like needs to be returned to atmospheric pressure when measuring the temperature. In particular, when the above-mentioned method is applied to a manufacturing device used in actual production, in many cases, the downtime of the device for more than 1 day is required. The downtime of such a device includes the time required for the operation before the temperature measurement and the time required for the operation after the temperature measurement.

Therefore, there is a problem at the production site that even if a defect occurs due to the stage heater of the manufacturing device, the temperature distribution of the stage cannot be quickly confirmed. Furthermore, when it is desired to improve productivity without using the above-mentioned method, only the following method is feasible: based on two-dimensional information such as the film thickness of the film-forming object and the uniformity of the surface of the film-forming object, etc., the cause of the failure is estimated, and then Confirm the temperature distribution of the platform. In this case, there is a problem that the temperature cannot be measured directly, and there is a problem that there is a lot of time loss.

As a method of avoiding the above-mentioned problems, a method described in Patent Document 1 without using a thermocouple has been proposed. The technique of Patent Document 1 is a method of evaluating a change in sheet resistance due to diffusion of implanted ions. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2004-39776

[Problem to be solved by the invention]

However, in the technique disclosed in Patent Document 1, since the temperature measurement is performed using the phenomenon that implanted ions diffuse in the substrate, there is a problem that the measurement temperature range is limited to a high temperature range of about 1000°C. In addition, the technique of Patent Document 1 has a problem that the temperature measuring wafer cannot be reused because ion diffusion is used. Furthermore, for temperature measurement, it is necessary to use a wafer for monitoring on which ions have been implanted. Therefore, the wafer for monitoring may differ from the actually processed substrate in terms of heat capacity and the like. Therefore, there is a problem that accurate temperature measurement corresponding to the processing in the manufacturing equipment used in actual production cannot be performed. Furthermore, even in processing equipment that processes objects to be processed other than silicon wafers, there is a need to perform temperature measurement.

This invention was made in view of the said situation, and it intends to achieve the following objects. 1. It is possible to measure the distribution of substrate temperature in a wider temperature range. 2. It can easily and accurately measure the difference between the temperature of the substrate in the temperature range (about 100°C ~ 600°C) commonly used in CVD (chemical vapor deposition) and PVD (physical vapor deposition, physical vapor deposition). distributed. 3. For the substrate being processed, the temperature can be accurately measured at multiple points throughout the entire surface of the substrate. 4. Provide temperature measuring elements and temperature measuring devices capable of repeated measurements. 5. It can accurately measure the temperature of the processed substrate. 6. No matter what kind of substrate can accurately measure the temperature. 7. Improve the workability of measuring the temperature of the processed substrate. [Technical means to solve the problem]

A temperature measurement method according to an aspect of the present invention is to heat-treat a temperature-measuring substrate on which a phase-change film whose physical quantity changes according to a temperature attained is laminated (processing temperature measurement heating step), and then heat-treat the above-mentioned temperature-measuring substrate. Afterwards (after the process temperature measurement heating step) the physical quantity of the phase change film is measured to obtain the measured physical quantity (physical quantity measuring step), based on the above-mentioned measured physical quantity (measured physical quantity obtained in the physical quantity measuring step) and the pre-calculated The relationship between the physical quantity and temperature, and the temperature and temperature distribution of the above-mentioned temperature-measuring substrate in the heat treatment of the above-mentioned temperature-measuring substrate (processing temperature measuring and heating step) (temperature calculating step). Thereby, the above-mentioned problems are solved. In the temperature measuring method according to an aspect of the present invention, the physical quantity to be measured and the physical quantity in the above-mentioned relationship may be any one of sheet resistance, optical refractive index, and extinction coefficient. In the temperature measurement method according to one aspect of the present invention, the temperature history of the above-mentioned phase change film may be initialized (initialization step). In the temperature measuring method according to an aspect of the present invention, when initializing the temperature history of the phase change film (initialization step), the phase change film may be heated to initialize the temperature history of the phase change film ( initializing heating step), and causing the phase change film to undergo a phase change by rapidly cooling the phase change film (phase change rapid cooling step). In the temperature measurement method according to an aspect of the present invention, the temperature measurement substrate having the phase change film whose temperature history has been initialized (initialization step) may be used in the heat treatment of the temperature measurement substrate (treatment temperature measurement heating step). substrate. In the temperature measurement method according to an aspect of the present invention, the temperature measurement substrate having the phase change film whose temperature history has been initialized (initialization step) may be reused. In the temperature measurement method according to the aspect of the present invention, the relationship between the physical quantity and the temperature of the surface of the temperature measurement substrate may be obtained in advance (calibration step). In the temperature measurement method according to an aspect of the present invention, when the relationship between the physical quantity and the temperature of the surface of the temperature measurement substrate is obtained in advance (calibration step), the temperature measurement substrate may be heated to a specific attained temperature and maintained. In a constant temperature state (constant temperature heating step), the physical quantity of the above-mentioned phase change film of the above-mentioned temperature measurement substrate is measured (physical quantity measurement step), based on heating the above-mentioned temperature measurement substrate to a specific temperature and maintaining it in a constant temperature state. (Constant temperature heating step), and the above-mentioned measured physical quantity of the above-mentioned phase-change film obtained by measuring the physical quantity of the above-mentioned phase-change film of the above-mentioned substrate for temperature measurement, and derive the relationship between the physical quantity of the above-mentioned phase-change film and temperature (for calibration) data creation steps). In the temperature measurement method according to an aspect of the present invention, the phase change film may be formed of a chalcogenide-based alloy capable of reversibly changing between an amorphous phase and a crystalline phase, and the phase change film may be changed to initialize the temperature history. The heating temperature at which the change film is heated (initialization heating step) is set higher than the temperature range in the heat treatment of the temperature measurement substrate on which the phase change film is laminated (processing temperature measurement heating step). In the temperature measuring method according to an aspect of the present invention, the above-mentioned phase change film may be formed of an alloy mainly composed of two or more selected from Ge, Sb, and Te, and the above-mentioned phase change film is laminated. The temperature range in the heat treatment with the substrate (processing temperature measurement heating step) is 100°C to 600°C. A temperature measuring device according to an aspect of the present invention includes a temperature measuring substrate on which a phase change film is laminated. The above-mentioned phase change film is formed of a chalcogenide-based alloy, and the chalcogenide-based alloy is any two or more selected from Ge, Sb, and Te, which are materials capable of reversibly changing between an amorphous phase and a crystalline phase. main component. Thereby, the above-mentioned problems are solved. In the temperature measurement device according to an aspect of the present invention, the temperature measurement substrate may include a cover film laminated on the phase change film. In the temperature measurement device according to an aspect of the present invention, an insulating film provided between the temperature measurement substrate and the phase change film may be provided. The method of forming a thin film according to an aspect of the present invention forms a film using the temperature distribution in the substrate surface set based on the temperature measured by the temperature measuring method of the above-mentioned aspect. The method of forming a thin film according to an aspect of the present invention forms a film using a temperature distribution in a substrate surface set based on a temperature measured using the temperature measuring device of the above-mentioned aspect.

The temperature measuring method according to an aspect of the present invention includes: a processing temperature measuring and heating step of heat-treating a substrate for temperature measuring on which a phase-change film layered with a phase change film whose physical quantity changes according to the temperature reached; a physical quantity measuring step of using Obtaining the measured physical quantity by measuring the physical quantity of the above-mentioned phase change film after the above-mentioned process temperature measuring and heating step; relationship, and obtain the temperature and temperature distribution of the above-mentioned temperature-measuring substrate in the above-mentioned process temperature measuring and heating step. Thereby, the temperature history of the temperature measuring substrate can be measured from the change of the physical quantity of the phase change film of the temperature measuring substrate. Specifically, it is possible to measure the in-plane temperature distribution of the substrate at the highest attained temperature obtained in the process temperature measurement heating step. Here, in the physical quantity measuring step, the measured physical quantity is obtained by measuring the physical quantity of a plurality of locations of the phase change film. Thereby, the in-plane temperature distribution representing the temperature change of the substrate can be obtained by one processing temperature measurement heating step. In this way, the physical quantity of the film surface is only measured at a plurality of locations, and the temperature distribution at the processing location can be obtained without other detection devices or other processing steps. In addition, there is no need for a thermocouple or other device configuration. Therefore, it is not necessary to return the pressure of the inner space of the vacuum chamber or the like, which is a closed space where the treatment is performed, to atmospheric pressure in the treatment temperature measurement heating step. In addition, in the process temperature measurement heating step, it is also possible to obtain a temperature measurement substrate by laminating a phase change film on a substrate having the same structure as that of the substrate to be processed. In this case, an extremely detailed and precise temperature distribution in film formation and other processes can be obtained. Specifically, the in-plane temperature distribution can be measured at the position where the phase change film is laminated on the surface of the substrate, that is, a processing position such as a film formation position. Furthermore, in an actual production site where a plurality of substrates are processed, the above-mentioned temperature measurement can be performed by merely mixing the substrate for temperature measurement into the plurality of substrates to be processed and performing the processing. Furthermore, there is no influence of putting a measurement device or a measurement machine other than the temperature measurement substrate into the chamber, and temperature measurement can be performed without causing downtime. In the present invention, the measured physical quantity (measurement result) is compared with the physical quantity (such as sheet resistance, refractive index, extinction coefficient), temperature, and correction characteristics of temperature distribution obtained in advance. Thereby, the temperature distribution on the stage of the processing device for processing the substrate can be obtained in detail. In addition, since the temperature can be measured only by forming the phase change film having the above-mentioned composition, the temperature can be accurately measured regardless of the type of the substrate or the type of heat treatment. Also, since the measurement can be performed using a temperature measuring substrate having the same configuration as the substrate to be processed, it is also possible to measure changes in film formation temperature and temperature distribution depending on the substrate and film structure. In addition, since the phase change film is used to measure temperature, the sensitivity and accuracy of temperature measurement will hardly deteriorate after using the phase change film several times, and the accuracy of temperature measurement can also be maintained.

In the temperature measurement method according to an aspect of the present invention, the physical quantity to be measured and the physical quantity of the relationship are any one of sheet resistance, optical refractive index, and extinction coefficient. Thereby, by comparing the measured physical quantity, which is the measurement result of the physical quantity, with the temperature and the correction characteristic of the temperature distribution, the temperature distribution on the stage of the processing apparatus for processing the substrate can be obtained in detail.

The temperature measurement method according to an aspect of the present invention further includes an initialization step of initializing the temperature history of the phase change film. Therefore, in the initialization step, the temperature history of the phase change film can be initialized. Accordingly, the temperature measurement substrate can be repeatedly used for temperature measurement.

In the temperature measurement method according to an aspect of the present invention, the initialization step includes: an initialization heating step of heating the phase change film to initialize the temperature history of the phase change film; and a phase change rapid cooling step by The phase change (for example, amorphization) of the phase change film occurs by rapidly cooling the phase change film. Thereby, in the initialization step, the phase change film is changed (amorphized) by heating and rapidly cooling the phase change film, so that the temperature history of the phase change film can be initialized. Accordingly, the temperature measurement substrate can be repeatedly used for temperature measurement. Also, the initialized (corrected) phase change film hardly deteriorates. Therefore, accurate temperature measurement results can be maintained during multiple temperature measurements. Furthermore, the initialization temperature of the phase change film and the change in sheet resistance caused by the temperature depend on the composition of the phase change film. Therefore, there is no need to recalculate the temperature in particular.

In the temperature measurement method according to an aspect of the present invention, in the process temperature measurement heating step, the temperature measurement substrate having the phase change film whose temperature history is initialized in the initialization step is used. Thereby, the temperature measurement substrate can be repeatedly used for temperature measurement. Also, by the initialization step, the temperature history of the phase change film can be reset, and the temperature characteristics of the phase change film hardly change (degrade). Therefore, accurate temperature measurement results can be maintained in multiple temperature measurements.

In the temperature measurement method according to an aspect of the present invention, the temperature measurement substrate having the phase change film is repeatedly used, and the temperature history of the phase change film is initialized by the initialization step. In this way, accurate temperature measurement results can be maintained during multiple temperature measurements. In addition, there is no need to prepare a new measurement substrate every time the temperature is measured. Therefore, temperature inspection can be performed quickly, and the workability and cost of temperature inspection can be improved.

The temperature measuring method according to one aspect of the present invention includes a calibration step of obtaining in advance the relationship between the physical quantity and temperature of the surface of the temperature measuring substrate. In the calibration step, the relationship between the maximum attainable temperature and the change of the physical quantity of the phase change film formed with a specific composition is clarified. The measurement result of the physical quantity obtained by measuring the physical quantity is the measured physical quantity. Only by comparing the measured physical quantity with the data obtained through the calibration step, the in-plane temperature distribution of the substrate in the temperature inspection can be accurately obtained. Moreover, since the temperature characteristics of the phase change film hardly change (degrade), accurate temperature measurement results can be maintained in multiple temperature measurements.

In the temperature measurement method according to an aspect of the present invention, the calibration step includes: a constant temperature heating step of heating the temperature measurement substrate to a specific temperature and maintaining it at a constant temperature; a physical quantity measurement step of heating the temperature measurement substrate. The physical quantity of the above-mentioned phase-change film on the substrate is measured; and the step of preparing data for calibration is to derive the above-mentioned phase change film according to the temperature achieved in the above-mentioned constant temperature heating step and the measured physical quantity of the above-mentioned phase-change film obtained in the above-mentioned physical quantity measurement step. Change the relationship between the physical quantity of the film and the temperature. Thereby, for a phase change film formed with a specific composition, the relationship between the highest attained temperature and the change in physical quantity is clarified. The measurement result of the physical quantity obtained by measuring the physical quantity is the measured physical quantity. Only by comparing the measured physical quantity with the data obtained through the calibration step, the in-plane temperature distribution of the substrate in the temperature inspection can be accurately obtained. Moreover, since the temperature characteristics of the phase change film hardly change (degrade), accurate temperature measurement results can be maintained in multiple temperature measurements.

In the temperature measuring method according to an aspect of the present invention, the phase change film is formed of a chalcogenide-based alloy capable of reversibly changing between an amorphous phase and a crystalline phase, and the heating temperature in the initial heating step is set higher than the above-mentioned Treatment temperature The temperature range in the heating step was determined. Thereby, in the initialization step, only by heating and rapidly cooling the phase change film, the phase change film can be initialized multiple times easily through phase transfer. Furthermore, the temperature characteristics of the phase change film hardly change (degrade) due to initialization. Therefore, accurate temperature measurement results can be maintained in multiple temperature measurements. Moreover, temperature measurement can be performed only by forming a phase change film having the above-mentioned composition, so accurate temperature measurement can be performed regardless of what kind of substrate is used.

In the temperature measuring method according to an aspect of the present invention, the phase change film is formed of an alloy mainly composed of any two or more selected from Ge, Sb, and Te, and the temperature range in the heating step for measuring the processing temperature is 100°C. ~600°C. Thereby, in the initialization step, only by heating and rapidly cooling the phase change film, the phase change film can be initialized multiple times easily through phase transfer. Furthermore, the temperature characteristics of the phase change film hardly change (degrade) due to initialization. Therefore, accurate temperature measurement results can be maintained in multiple temperature measurements. Furthermore, a substrate for temperature measurement can be prepared only by laminating a phase change film with a specific composition on a substrate having the same structure as the processing substrate.

In the temperature measurement method according to an aspect of the present invention, in the process temperature measurement heating step, the temperature measurement substrate is heated inside a substrate processing apparatus. Thereby, the temperature distribution at the substrate position inside the substrate processing apparatus, that is, the temperature distribution at the actual substrate position during substrate processing can be measured.

A temperature measuring device according to an aspect of the present invention is provided with a substrate for temperature measurement on which a phase change film is laminated. The phase change film is formed of a chalcogenide-based alloy selected from a material capable of forming an amorphous phase and a chalcogenide-based alloy. Any two or more of Ge, Sb, and Te in a material reversibly changing between crystal phases are the main components.

In the temperature measurement device according to one aspect of the present invention, the temperature measurement substrate includes a cover film laminated on the phase change film. Thereby, even if the heat treatment that needs to be measured in the heating step of the treatment temperature measurement is a treatment that damages the surface of the substrate such as plasma treatment, it will not affect the phase change film, and accurate temperature measurement can be performed. Furthermore, if the resistance value of the cover film is higher than that of the phase change film measured in the physical quantity measuring step, the sheet resistance of the phase change film can be adjusted without being affected by the resistance value of the cover film. Changes are measured. Furthermore, the cover film is preferably a film whose physical quantity does not change to such an extent that the physical quantity does not affect the measurement due to heat treatment.

A temperature measurement device according to an aspect of the present invention includes an insulating film provided between the temperature measurement substrate and the phase change film. Thereby, even if the substrate on which the phase change film is laminated has a conductivity distribution that affects the measurement of the physical quantity of the phase change film, it is possible to prevent the influence of the heat treatment on the phase change film from affecting the measurement of the physical quantity. Also, for example, when using a substrate that is not a bare silicon substrate but has wiring, N regions, P regions, insulating films, etc. formed, it is also possible to prevent the influence of the heat treatment on the phase change film from affecting the measurement of physical quantities. Accordingly, accurate temperature distribution can be measured even for a substrate with an uneven structure. Accordingly, even for a substrate having a non-uniform temperature characteristic distribution, it is possible to measure the temperature state distribution during heat treatment.

The method of forming a thin film according to an aspect of the present invention forms a film using the temperature distribution in the substrate surface set based on the temperature measured by the above-mentioned temperature measuring method. The method of forming a thin film according to an aspect of the present invention forms a film using a temperature distribution in a substrate surface set based on a temperature measured using the above-mentioned temperature measuring device. Thereby, the in-plane temperature distribution of the substrate during substrate processing can be made uniform, thereby improving the in-plane uniformity of film-forming characteristics such as film thickness, resistance value, and composition. Here, when setting the in-plane temperature distribution of the substrate used in the film formation step based on the temperature measured by the temperature measurement method, the state of the plasma to be formed, the flow of the supplied gas, or the The control such as the heater control state in the susceptor on which the processed substrate is placed is performed under specific conditions. [Effect of Invention]

According to one aspect of the present invention, the following effects can be obtained. The distribution of the substrate temperature in a wider temperature band can be measured. The temperature distribution of the substrate in the temperature range (about 100°C to 600°C) commonly used in CVD and PVD can be measured easily and accurately. For a substrate in process, it is possible to accurately measure the temperature at multiple points over the entire surface of the substrate. A temperature measuring element and a temperature measuring device capable of repeated measurement can be provided. It is possible to perform temperature measurement which can be regarded as the accurate temperature of the substrate being processed. The temperature can be accurately measured regardless of the substrate. The operability of measuring the temperature of the processed substrate can be improved.

Hereinafter, the temperature measuring method, the temperature measuring device, and the thin film forming method according to the first embodiment of the present invention will be described based on the drawings. Fig. 1 is a schematic sectional view showing a temperature measuring device according to a first embodiment. Fig. 2 is a schematic sectional view showing a device for measuring temperature in the temperature measuring method of the first embodiment. Fig. 3 is a flow chart showing the temperature measurement method of the first embodiment. Fig. 4 is a graph showing the characteristics of the phase change film of the first embodiment. Fig. 5 is a graph showing the characteristics of the phase change film of the first embodiment. In Fig. 3, the symbol MW is a temperature measuring device.

In the first embodiment, the sheet resistance is exemplified as the physical quantity to be measured. In addition, the first embodiment is not limited to the substrate processing apparatus disclosed below. The temperature measuring method of the first embodiment measures the temperature during processing in the device using the temperature measuring substrate MW shown in FIG. 1 as a temperature measuring device. As shown in FIG. 1 , in the substrate MW for temperature measurement of the first embodiment, a phase change film MW2 and a cover film MW3 are laminated on a substrate MW1 .

The substrate MW1 is a silicon single crystal substrate (silicon wafer). The substrate MW1 of the first embodiment is a bare silicon wafer. In addition, an ion implantation region such as an N region, a P region, and the like is not particularly formed on the substrate MW1 of the first embodiment. Moreover, no wiring etc. are formed in the board|substrate MW1 of 1st Embodiment, either. Furthermore, as described below, specific regions, wiring, and the like can be formed on the substrate MW1.

The phase change film MW2 is formed on the whole surface of the board|substrate MW1. The phase change film MW2 is a material capable of reversibly changing between an amorphous phase and a crystalline phase. Specifically, the phase change film MW2 is a chalcogenide-based material represented by, for example, GST (an alloy layer mainly composed of any two or more selected from Ge, Sb, and Te), and a chalcogenide-based material similar to that of a chalcogenide-based material. The material is formed. Here, the GST film has a composition in which a phase change region exists at 100°C to 600°C. GST film is a film whose sheet resistance, optical refractive index, and extinction coefficient change with phase change.

The phase change film MW2 of the first embodiment is formed so as to have the same composition ratio over the entire surface of the phase change film MW2. That is, the phase change film MW2 of the first embodiment is formed so that the in-plane composition distribution is the same over the entire surface of the phase change film MW2. Furthermore, as described below, the phase change film MW2 of the first embodiment may be formed so as to have different composition ratios along the direction along the surface of the substrate MW1. In addition, the phase change film MW2 of the first embodiment is formed so as to have the same composition ratio over the entire length in the film thickness direction.

In addition, the phase change film MW2 of the first embodiment may have a film thickness of 1 nm to 100 μm, more preferably 10 nm to 1000 nm. When the film thickness of the phase change film MW2 is less than the above-mentioned film thickness range, the detection of the sheet resistance may not be accurate, which is not preferable. Moreover, when the film thickness of the phase change film MW2 is larger than the said film thickness range, since manufacturing cost becomes high, it is unpreferable.

The phase change film MW2 of the first embodiment is made of a phase change material having a specific crystallization temperature. When the temperature is raised, part of the amorphous phase change material crystallizes from the amorphous reset state to the crystalline set state. The electrical resistivity differs between the crystalline set state and the amorphous reset state of a phase change material. Therefore, when the phase change material changes from an amorphous state to a crystalline state due to an increase in temperature, it is preserved in this state. For example, for the phase change film MW2, Ge/Sb ₂ Te ₃ , Ge ₂ Sb ₁ Te ₂ , Ge _x Sb _y Te _z (x is 30% or more, 40% or more) as GeSbTe (hereinafter referred to as GST) composition can be exemplified. ), Ge-Sb ₂ Te ₃ , Ge ₂ Sb ₁ Te ₂ , Ge _x Sb _y Tez ( _x is about 42.9%, y is about 20.5%, z is about 36.6%), etc. The material of the phase change film MW2 is, for example, nitrogen, silicon, oxygen, silicon dioxide, silicon nitride, copper, silver, gold, aluminum, aluminum oxide, tantalum, tantalum oxide, tantalum nitride, titanium, and titanium oxide. Specific impurities can be doped into the material of the phase change film MW2. Thereby, the phase change material constituting the phase change film MW2 can be set as the state of the phase change film MW2 in such a manner that it has specific characteristics in terms of conductivity, transition temperature, melting temperature, and other characteristics.

The cover film MW3 protects the surface of the phase change film MW2. The cover film MW3 has a resistance value capable of measuring the sheet resistance of the phase change film MW2 by the four-deep needle method. The sheet resistance value of the cover film MW3 preferably has a value that does not change to such an extent that the sheet resistance value does not affect measurement due to heat treatment. It is preferable to configure the cover film MW3 so that even when the physical quantity to be measured is a refractive index or an extinction coefficient, the physical quantity can be measured without affecting the measurement of the physical quantity. The cover film MW3 is a film that does not allow unnecessary substances to adhere to the phase change film MW2, or does not change the film properties of the phase change film MW2 due to the adsorption of excess substances. In addition, the cover film MW3 is a film that does not expose the phase change film MW2 to the outside. The material of the cover film MW3 is, for example, doped silicon nitride film, silicon oxide, insulating film such as polysilicon, titanium nitride, titanium oxide film, and the like.

In addition, the film thickness of the cover film MW3 in the first embodiment can be set within a range of 0.5 nm to 100 nm, more preferably within a range of 1 nm to 50 nm.

The temperature measurement method of the first embodiment is carried out in a heat treatment apparatus such as a plasma CVD apparatus 1 as shown in FIG. 2 . In addition, the heat treatment apparatus shown in FIG. 2 is shown as an example of a processing apparatus. The temperature measuring method of the first embodiment can also be performed using an apparatus having another configuration.

The plasma CVD apparatus 1 of the first embodiment includes: a first electrode (upper electrode) arranged in the inner space of the vacuum processing tank; a second electrode (lower electrode) arranged in the inner space facing the first electrode. , which is used to mount the substrate (object to be processed) and has a built-in temperature control part; the shower plate is arranged on the second electrode side of the first electrode, and is arranged opposite to the substrate; the first power supply is applied to the first electrode. High-frequency AC voltage above 2 MHz; second power supply, which applies low-frequency AC voltage between 100 kHz and 1 MHz to the second electrode; gas introduction part, which is located on the first electrode and the shower plate from the outside of the vacuum processing tank The process gas is introduced into the space between them; and the exhaust device adjusts the internal space of the vacuum processing tank to the required pressure. Furthermore, in the plasma CVD apparatus 1 of the first embodiment, the distance (T/S) between the surface of the second electrode on which the substrate is placed and the surface of the shower plate facing the second electrode (T/S) is 5 mm or more and 100 mm. the following.

As shown in FIG. 2 , a plasma CVD apparatus 1 (plasma processing apparatus) includes a processing chamber 101 having a film formation space 2 a (inner space) as a reaction chamber. The processing chamber 101 includes a vacuum chamber 2 (vacuum processing tank), an electrode flange 4 (first electrode, upper electrode), and an insulating flange 81 . The insulating flange 81 is sandwiched by the vacuum chamber 2 and the electrode flange 4 .

An opening is formed at the bottom 11 of the vacuum chamber 2 . The strut 25 is inserted through the opening. The pillar 25 is disposed at the lower part of the vacuum chamber 2 . Inside the vacuum chamber 2 , the second electrode 15 (support portion, lower electrode) is connected to the front end of the pillar 25 . The second electrode 15 incorporates a plate-shaped heater 16 (temperature control unit). In addition, an exhaust pipe 27 is connected to the vacuum chamber 2 . A vacuum pump 28 is provided at the front end of the exhaust pipe 27 . The vacuum pump 28 decompresses so that the internal environment of the vacuum chamber 2 becomes a vacuum state.

In addition, the support column 25 is connected to an elevating mechanism (not shown) provided outside the vacuum chamber 2, and can move up and down in the vertical direction of the substrate 10 (object to be processed). That is, the second electrode 15 connected to the front end of the pillar 25 is configured to be able to move up and down in the vertical direction. In addition, a bellows (not shown) is provided outside the vacuum chamber 2 so as to cover the outer periphery of the pillar 25 .

The electrode flange 4 has an upper wall 41 and a peripheral wall 43 . The electrode flange 4 is arranged such that the opening is located below in the vertical direction of the base body 10 (substrate). Moreover, the shower plate 5 is attached to the opening part of the electrode flange 4. As shown in FIG. Thereby, a space 24 is formed between the electrode flange 4 and the shower plate 5 . In addition, the electrode flange 4 has an upper wall 41 facing the shower plate 5 . A gas introduction port 42 is provided on the upper wall 41 .

Furthermore, a gas introduction pipe 7 is provided between the process gas supply unit 21 and the gas introduction port 42 provided outside the processing chamber 101 . One end of the gas introduction pipe 7 is connected to the gas introduction port 42 . The other end of the gas introduction pipe 7 is connected to a process gas supply unit 21 . The process gas is supplied from the process gas supply unit 21 to the space 24 through the gas introduction pipe 7 . That is, the space 24 functions as a gas introduction space into which a process gas is introduced.

The electrode flange 4 and the shower plate 5 are each made of a conductive material. The electrode flange 4 is electrically connected to an RF (radio frequency, radio frequency) power source 9 (first power source) disposed outside the processing chamber 101 . The RF power source 9 is a high-frequency power source that applies a high-frequency AC voltage of 2 MHz or more to the electrode flange 4 . That is, the electrode flange 4 and the shower plate 5 constitute a cathode electrode. A plurality of gas ejection ports 6 are formed in the shower plate 5 . The process gas introduced into the space 24 is ejected from the gas ejection port 6 to the film forming space 2 a in the vacuum chamber 2 .

The process gas introduced into the space 24 from the process gas supply part 21 through the gas introduction pipe 7 and the gas introduction port 42 is ejected into the vacuum chamber 2 through the gas ejection port 6 of the shower plate 5 . The space 24 is the space on the upstream side of the shower plate 5 . The interior of the vacuum chamber 2 is the space on the downstream side of the shower plate 5 .

The second electrode 15 is a plate-shaped member whose surface is formed flat. The substrate 10 is placed on the upper surface of the second electrode 15 . The second electrode 15 functions as a ground electrode, that is, as an anode electrode.

When the process gas is ejected from the gas ejection port 6 with the substrate 10 disposed on the second electrode 15 , the process gas is supplied to the space on the processing surface 10 a of the substrate 10 . Also, a heater 16 is provided inside the second electrode. The temperature of the second electrode is adjusted to a specific temperature by a heater.

On the outer periphery of the second electrode 15 , a plurality of ground wires 30 are arranged at approximately equal intervals to connect the second electrode 15 and the vacuum chamber 2 . The ground wire 30 is made of, for example, a nickel-based alloy, an aluminum alloy, or the like.

A second power source 17 is connected to the second electrode 15 . The second power source 17 is a high-frequency power source that applies a low-frequency AC voltage (bias voltage) of 100 kHz to 1 MHz to the second electrode 15 . When the second electrode receiving the AC voltage generates plasma in the film-forming space 2a, it feeds a negative potential into the plasma space, that is, it functions as a cathode to feed ionic particles into the substrate 10, thereby improving the straight forward movement of the ionic particles relative to the substrate 10. sex. Thereby, the material gas decomposed by the plasma can be smoothly transported in the direction of the substrate, and the film forming speed or the alignment of the film can be improved. Thereby, when a thin film is formed inside a structure having a high aspect ratio (such as a micropore), the covering property (coverage) of the thin film can be improved. Furthermore, for example, by changing the bias power without changing the film-forming speed, the value of internal stress, which is one of the characteristics of the obtained thin film, can be controlled in a wide range. For example, the value of the internal stress of the film can be controlled so as to be in the range of 0 to a positive value (positive), or the value of the internal stress of the film can be controlled to be in the range of a negative value (negative) to 0 .

In the plasma CVD apparatus 1 of the first embodiment, the distance (T/S) between the surface 15a of the second electrode 15 on which the substrate 10 is placed and the surface 5a of the shower plate 5 that faces the second electrode 15 is 15 More than 40 mm and less than 40 mm. According to the plasma CVD apparatus 1 of the first embodiment, by making the distance (T/S ) is not less than 15 mm and not more than 40 mm, and the space where the process gas introduced between the surface 15a and the surface 5a becomes wider. That is, more gas can be introduced into the film-forming space 2a, thereby promoting the decomposition of the process gas. In the plasma CVD apparatus 1 according to the embodiment of the present invention, the film formation rate can be maintained, and the film formation can also be performed in a lower temperature range (180° C. or less) than before (190° C. or higher).

The plasma CVD apparatus 1 of the first embodiment can have T/S in the range of 15 mm to 40 mm. In the plasma CVD apparatus 1, the characteristics of the obtained film can be maintained, and film formation can be performed at a lower temperature (for example, 200° C. or lower) than before.

Next, the case where a thin film is formed on the processing surface 10a of the substrate 10 using the plasma CVD apparatus 1 will be described. Here, a case where a silicon oxide film is formed as a thin film is taken as an example for description.

First, the inside of the vacuum chamber 2 is depressurized using the vacuum pump 28 . With the inside of the vacuum chamber 2 maintained in a vacuum state, the substrate 10 is carried into the film formation space 2 a in the vacuum chamber 2 and placed on the second electrode 15 . Here, before the substrate 10 is placed, the second electrode 15 is positioned below the vacuum chamber 2 . That is, since the distance between the second electrode 15 and the shower plate 5 is widened before the substrate 10 is carried in, the substrate 10 can be easily placed on the second electrode 15 using a robot arm (not shown).

After the substrate 10 is placed on the second electrode 15, the lifting mechanism is activated to lift the pillar 25 upward, and the substrate 10 placed on the second electrode 15 also moves upward. By this operation, the distance between the shower plate 5 and the base 10 is determined to be a desired distance so that the distance between the shower plate 5 and the base 10 is properly formed into a film, and the distance is maintained. Here, the distance between the shower plate 5 and the base 10 is maintained at a distance suitable for forming a film on the base 10 .

Specifically, the distance (T/S) between the surface 15a of the second electrode 15 on which the substrate 10 is placed and the surface 5a of the shower plate 5 and the surface 5a facing the second electrode 15 is set within the range of 15 mm to 40 mm. . Thereby, the space where the process gas introduced can be made wider. That is, more gas can be introduced into the film-forming space 2a, thereby promoting the decomposition of the process gas. As a result, film formation can be efficiently performed even in a low temperature range (180° C. or lower) lower than the conventional temperature (190° C. or higher). As a result, the film formation rate can be maintained, and film formation can be performed at a lower process temperature (for example, 180° C. or lower).

Thereafter, the process gas is introduced from the process gas supply unit 21 into the first space 24 a through the gas introduction pipe 7 and the gas introduction port 42 . In particular, in the first embodiment, tetraethoxysilane (abbreviated as TEOS, tetraethoxysilane (Si(OC ₂ H ₅ ) ₄ ) or monosilane (SiH ₄ ) is used as the raw material of the process gas.

Thereby, a silicon oxide film can be formed on the substrate 10 . Also, by increasing the flow rate of the process gas, the film formation rate can be increased. That is, high-speed film formation can be realized. Then, the process gas is supplied to the film formation space 2 a in the vacuum chamber 2 through the gas ejection port 6 of the shower plate 5 . At this time, the pressure Pe of the film formation space 2 a is reduced by the air conduction A of the shower plate 5 .

Next, the RF power supply 9 is activated to apply a high-frequency voltage to the electrode flange 4 . At this time, the electrode flange 4 is electrically insulated from the vacuum chamber 2 via the insulating flange 81 . Also, the vacuum chamber 2 is grounded. In this structure, a high-frequency voltage is applied between the shower plate 5 and the second electrode 15 to generate a discharge, and plasma is generated between the shower plate 5 provided on the electrode flange 4 and the treated surface 10 a of the substrate 10 .

The process gas is decomposed in the generated plasma to obtain the process gas in the plasma state, and a vapor phase growth reaction occurs on the processing surface 10a of the substrate 10 to form a thin film on the processing surface 10a. At this time, by applying a bias voltage from the second power supply 17 to the substrate 10, the raw material gas decomposed by the plasma can be smoothly transported in the direction of the substrate, thereby improving the film forming speed or the alignment of the thin film.

Specifically, in the film-forming method of the first embodiment, the film-forming rate [nm/min] for forming the silicon oxide film on the substrate 10 is 80 to 360. According to the film forming method of the first embodiment, only by changing the TEOS flow rate, the film forming rate [nm/min] can be increased to about 4.5 times from 80 to 360. Also, within this range, by changing the bias power, it is possible to control the value of the internal stress, which is one of the characteristics of the obtained thin film, in a wide range. For example, the value of the internal stress of the film can be controlled so as to be in the range of 0 to a positive value (positive), or the value of the internal stress of the film can be controlled to be in the range of a negative value (negative) to 0.

The temperature measurement substrate MW which is an example of the temperature measurement device of the first embodiment measures the temperature during the process of the plasma CVD apparatus 1 . Here, as described above, the substrate 10 being processed is in a vacuum environment or a plasma environment. Therefore, it is not possible to directly measure the temperature of such a substrate 10 . Accordingly, the maximum attained temperature of the substrate 10 during processing is measured using the temperature measurement substrate MW as described below.

As shown in FIG. 3, the temperature measurement method of the first embodiment includes a substrate preparation step S00, a calibration step S10 (calibration step), an initialization step S20, a process temperature measurement preparation step S31, a process temperature measurement heating step S32, and a sheet resistance measurement step. S33, temperature calculation step S34, and subsequent step S40.

In the substrate preparation step S00 shown in FIG. 3 , the substrate MW for temperature measurement is prepared. Here, the substrate MW for temperature measurement has a temperature measurement surface whose front MWa corresponds to the processing surface 10 a of the base body 10 . In addition, the substrate MW for temperature measurement is the substrate MW1 having the same properties as the base body 10 such as heat capacity. In the substrate MW for temperature measurement, the composition ratio of the phase change film MW2 is set so that it may be in the range which can perform the assumed temperature measurement. For example, in Ge _{x Sby} Tez representing the composition of the GST film, it can be set such that the atomic percentage concentration _x of Ge is in the range of 10% to 50%, and the atomic percentage concentration y of Sb is 10%. In the range of ~50%, the Te atomic percentage concentration z is in the range of 20% to 80%.

In the substrate preparation step S00, the phase change film MW2 having the above composition ratio is formed on the entire surface of the substrate MW1. Furthermore, the cover film MW3 having the above composition is formed on the entire surface of the phase change film MW2.

The calibration step S10 shown in FIG. 3 includes a constant temperature heating step S11, a sheet resistance measurement step S12, and a calibration data preparation step S13.

In the constant temperature heating step S11 shown in FIG. 3 , the substrate MW for temperature measurement manufactured in the substrate preparation step S00 is heated by a known heat source such as a constant temperature furnace and maintained at a specific high temperature. Here, the constant temperature heating step S11 is a heating step for measuring the temperature-sheet characteristics of the phase change film MW2. After maintaining the high temperature state for a specific time, the temperature is lowered to end the constant temperature heating step S11.

The sheet resistance measuring step S12 shown in FIG. 3 is to measure the sheet resistance with respect to the temperature heated in the constant temperature heating step S11. Here, in order to obtain the sheet resistance value of the entire surface of the phase change film MW2, measurement was performed at multiple points by the four-deep needle measurement method. For example, on a Φ300 mm wafer, it can be measured at about 120 measurement positions. If necessary, the above constant temperature heating step S11 and the sheet resistance measuring step S12 can be repeated to measure a plurality of sheet resistance values corresponding to different temperatures.

In the calibration data creation step S13 shown in FIG. 3 , the temperature-sheet resistance change relationship obtained by repeating the constant temperature heating step S11 and the sheet resistance measurement step S12 is obtained. Here, the obtained data will change according to the assumed ratio of the phase change film MW2, and become the calibration data shown in FIG. 4, for example. If necessary, for the above-mentioned substrate MW for temperature measurement, the corresponding calibration data can be obtained through the phase change film MW2 with different compositions.

The initialization step S20 shown in FIG. 3 includes an initialization heating step S21 and an amorphization step S22 (phase change step). In the initialization heating step S21 shown in FIG. 3 , the phase change film MW2 is heated to a temperature capable of initializing the temperature history of the phase change film MW2 . In the amorphization step S22 shown in FIG. 3 , following the initialization heating step S21 , the phase change film MW2 is rapidly cooled to change its phase (amorphization). Thereby, the temperature history of the phase change film MW2 is initialized. The heating and rapid cooling method at this time is not limited to the method of using a constant temperature bath or the like, but may be a heating and rapid cooling method performed by directly energizing the temperature measurement substrate MW.

In the initialization step S20, the heating temperature in the initialization heating step S21 is set higher than the measurement temperature in the subsequent step. That is, it is set higher than 200° C. to 600° C. which is the phase change region of the GST film as the phase change film MW2 . Thus, the heating temperature in the initialization heating step S21 can be set higher than 600°C. In addition, the heating time in the initialization heating step S21 is preferably set between 1 and 1800 seconds, so as to enable phase transition required for amorphization.

In the initialization step S20, the cooling rate in the amorphization step S22 is set to a value capable of amorphization.

Here, the heating conditions and rapid cooling conditions in the initialization step S20 depend on the composition of the phase change film MW2.

The processing temperature measurement preparation step S31 shown in FIG. 3 is a preparation step for satisfying the conditions for enabling temperature measurement. Specifically, it is performed in the same manner as the film forming step in the CVD apparatus 1 . However, the CVD apparatus 1 of the first embodiment is an example of the embodiment of the present invention, and the embodiment of the present invention is not limited to the plasma CVD apparatus. For example, it can also be applied to a thermal ALD (atomic layer deposition) device, a plasma ALD device, an ALE (atomic layer etching) device, a PVD device, an etching device, etc. having the same structure.

First, the inside of the vacuum chamber 2 is depressurized using the vacuum pump 28 . With the internal environment of the vacuum chamber 2 maintained in a vacuum state, the substrate MW for temperature measurement is carried into the film formation space 2 a in the vacuum chamber 2 and placed on the second electrode 15 . At this time, the substrate MW for temperature measurement is placed such that the front surface MWa corresponds to the processing surface 10 a of the base body 10 . That is, it mounts so that the phase change film MW2 may become an upper surface. Here, the second electrode 15 is located below the inside of the vacuum chamber 2 before the substrate MW for temperature measurement is mounted. That is, since the distance between the second electrode 15 and the shower plate 5 is widened before the base body 10 is carried in, the temperature measurement substrate MW can be easily placed on the second electrode 15 using a robot arm.

After the substrate 10 is placed on the second electrode 15 , the lifting mechanism is activated to lift the pillar 25 upward, and the temperature measurement substrate MW placed on the second electrode 15 also moves upward. Thereby, the space|interval between the shower plate 5 and the board|substrate MW for temperature measurement is determined so that it may become the same condition as the space|interval required for film formation, and this space|interval is maintained. Here, the distance between the shower plate 5 and the temperature measurement substrate MW is kept equal to the distance suitable for forming a film on the base body 10 .

Thereafter, the process gas is introduced from the process gas supply unit 21 into the first space 24 a through the gas introduction pipe 7 and the gas introduction port 42 .

Then, the process gas is supplied to the film formation space 2 a in the vacuum chamber 2 through the gas ejection port 6 of the shower plate 5 . At this time, the pressure Pe of the film formation space 2 a is reduced by the air conduction A of the shower plate 5 . Furthermore, as the ambient gas, it is preferable to use an inert gas suitable for film formation.

Heating is performed in the processing temperature measurement heating step S32 shown in FIG. 3 . Here, the RF power supply 9 may be activated to apply a high-frequency voltage to the electrode flange 4 as in the case of film formation.

In the processing temperature measurement heating step S32 shown in FIG. 3 , the same conditions as those for the processing of the substrate 10 are set. Specifically, the same heating temperature as that for the substrate 10 is set. The same heating time as that for the substrate 10 is set. After the set heating time has elapsed, the application of the high-frequency voltage from the RF power source 9 is stopped. Thereafter, the substrate MW for temperature measurement is carried out from the vacuum chamber 2 .

In the sheet resistance measurement step S33 shown in FIG. 3 , the sheet resistance of the temperature measurement substrate MW is measured in the same manner as in the sheet resistance measurement step S12 . The point to note here is that the environment for performing the above sheet resistance measurement step S12 is preferably an inert gas environment. It should be noted that the sheet resistance measuring step S33 is the same as the sheet resistance measuring step S12 in terms of process conditions such as thermal conductivity, molecular weight, or viscosity.

In the temperature calculation step S34 shown in FIG. 3 , the processing temperature is calculated based on the value of the sheet resistance measured in the sheet resistance measurement step S33 and the temperature-sheet resistance relationship obtained in the calibration data preparation step S13, and the processing temperature measurement heating step S32 is calculated. The highest temperature is reached. Here, based on the calibration curve shown in FIG. 4 corresponding to the phase change film MW2, the in-plane temperature distribution of the temperature measurement substrate MW during the film formation process was calculated by measuring the sheet resistance.

In subsequent step S40 shown in FIG. 3 , the in-plane temperature distribution calculated in step S34 can be calculated according to the temperature, and the heating conditions can be changed to obtain the temperature and in-plane uniformity when forming a film on the substrate 10 to form a film.

In addition, when the temperature measurement substrate MW is used for temperature measurement after the temperature calculation step S34 shown in FIG. 3 is completed, the process proceeds to the initialization step S20 to perform initialization of the temperature measurement substrate MW. Thereby, the temperature measurement substrate MW can be repeatedly used for temperature measurement.

In the first embodiment, temperature measurement can be performed using the resistance change of the phase change film MW2 formed on the substrate MW1 which is a silicon wafer. Here, temperature measurement can be performed at 100° C. to 600° C. which is a phase change region of the GST film which is the phase change film MW2 .

Also, in the first embodiment, the sheet resistance, refractive index, extinction coefficient, temperature correction characteristics of the phase change film MW2 obtained in advance in the calibration data preparation step S13, and the measurement results in the processing temperature measurement and heating step S32 are carried out. Compare. Thereby, the in-plane temperature distribution of the temperature measurement substrate MW on the stage (second electrode) 15 can be obtained in detail. Thereby, the in-plane temperature distribution corresponding to the substrate 10 on the stage (second electrode) 15 during the plasma CVD process can be obtained in detail. In addition, in the initialization step S20, the phase change film MW2 can be returned to amorphization by heating after use and then rapidly cooling, and the temperature measurement substrate MW can also be reused.

In the first embodiment, it is possible to measure the temperature history of the temperature-measuring substrate MW based on the change in the sheet resistance of the phase-change film MW2 of the temperature-measuring substrate MW, specifically, the maximum attained temperature in the process temperature measurement heating step S32. The in-plane temperature distribution of the substrate. At the same time, in the initialization step S20 , the temperature history is initialized by making the phase change film MW2 amorphized, whereby the temperature measurement substrate MW can be repeatedly used for temperature measurement. Conventionally, it was necessary to prepare a new measurement device every time a temperature measurement was performed. On the other hand, in the first embodiment, it is not necessary to prepare a new measurement device, and it is possible to improve the workability of temperature measurement and reduce the cost.

In the sheet resistance measurement step S33, by measuring the sheet resistance of a plurality of parts of the phase change film MW2, the in-plane temperature distribution representing the temperature change of the temperature measurement substrate MW can be obtained by one process temperature measurement heating step S32 . Thus, the sheet resistance of the phase change film MW2 is only measured at a plurality of locations, and the temperature distribution at the processing locations can be obtained without other detection devices or other processing steps.

In addition, only the substrate MW for temperature measurement having substantially the same configuration as the substrate 10 subjected to the plasma CVD process is transferred to the vacuum chamber 2 in the same procedure as the substrate 10 to be processed, and the temperature measurement is carried out in the vacuum chamber 2. After processing, temperature measurement can be carried out. Therefore, complex devices such as thermocouples are not required. In particular, there is no need for a redundant device configuration that needs to communicate with the outside of the processing device or a cause of interference with measurement. Furthermore, there is no need to insert a device configuration that may become a source of contamination into the vacuum chamber 2 that needs to be kept clean in order to maintain film-forming properties. Therefore, in the processing temperature measurement heating step S32, the internal space of the vacuum chamber 2 etc. which is a closed space for processing will not be polluted.

In addition, in the processing temperature measurement and heating step S32, only by laminating the phase change film MW2 on the substrate MW1 having the same structure as the substrate 10 to be processed, it is possible to measure extremely detailed and precise temperature distribution during film formation and other processing. That is, it is possible to measure an extremely accurate in-plane temperature distribution at an accurate processing position on the stage (second electrode) 15 where the phase change film MW2 is deposited on the surface of the substrate MW1, which is the film formation position.

Furthermore, in the first embodiment, at a production site where a plurality of substrates 10 are continuously processed, the temperature measurement process can be easily performed by merely mixing the temperature measurement substrate MW in the middle of processing the plurality of substrates (substrates to be processed) 10 . With this procedure alone, it is possible not to affect the film-forming space 2a serving as the reaction chamber, such as putting measurement devices other than the temperature measurement substrate MW into the chamber, and there is no problem with the processing devices used in actual mass production. The temperature measurement is performed during downtime. At the same time, accurate temperature measurement can be performed without reducing the productivity of multiple processes of the substrate 10 at the manufacturing site.

In the first embodiment, the previously measured sheet resistance, refractive index, extinction coefficient, and temperature correction characteristics of the phase change film MW2 are compared with the measurement results of the process temperature measurement and heating step S32. Thereby, the temperature distribution on the actual platform 15 for processing the substrate 10 can be obtained in detail and easily.

Moreover, temperature measurement can be performed only by forming the phase change film MW2 which has a specific composition as mentioned above on the board|substrate MW1. Therefore, accurate temperature measurement can be performed regardless of the type of substrate and the type of heat treatment of the base body 10 . That is, in any step of processing wafer-shaped substrates such as silicon SiC, silicon nitride, gallium nitride, gallium arsenide, gallium phosphide, indium gallium, and sapphire, or different types of substrates such as glass substrates, it is possible to The in-plane temperature measurement of the substrate 10 to be processed can be easily and accurately performed.

Temperature measurement can be performed only by forming the phase change film MW2 on the substrate MW1. Therefore, temperature measurement can be performed using the temperature measurement substrate MW having substantially the same configuration as the substrate 10 to be processed, that is, the substrate 10 formed into a film by the plasma CVD process.

Therefore, it is possible to use the same substrate MW1 as the substrate 10 that is being processed in a specific process in the middle of the plurality of steps or in the final step of the plurality of steps. That is, the temperature measurement method of the first embodiment can be applied even if the substrate 10 in a state where trenches, wirings, doped regions such as PN, etc. are formed is not processed on a bare wafer. In this case, for example, the temperature measurement method can be performed as follows. First, as the substrate MW for temperature measurement, a substrate in which the phase change film MW2 is added to the substrate MW1 having the same configuration as the above-mentioned grooves, wirings, doped regions such as PN, etc. is prepared. Thereafter, the substrate MW for temperature measurement is mixed into the plurality of substrates 10 and processed continuously. Thereby, the above-mentioned temperature measuring method can be performed.

Thereby, even if the substrate MW1 corresponding to the substrate 10 of the laminated phase change film MW2 has a conductivity distribution that affects the sheet resistance measurement of the phase change film MW2, it is possible to prevent damage to the phase change film MW2 due to heat treatment. Influenced by sheet resistance measurement. Also, for example, even when the substrate MW1 corresponding to the substrate 10 on which wiring, N regions, and P regions, etc. are formed is used instead of a bare silicon substrate, damage to the sheet resistance due to heat treatment of the phase change film MW2 can be prevented. The measurement is affected. Thereby, even if it is the base body 10 with an uneven structure, accurate temperature distribution can be measured. Thereby, even if it is the base body 10 which has a non-uniform temperature characteristic distribution, the temperature state distribution in heat processing can be measured.

Furthermore, the temperature distribution inside the plasma CVD apparatus 1 can be accurately measured in conjunction with this process. That is, even when the substrate 10 to be processed has non-uniform heat capacity distribution or non-uniform electrical properties, it is possible to measure the temperature distribution at an accurate processing position in the plasma CVD apparatus 1 . Thereby, without reducing the productivity of the substrate processing at the manufacturing site, it is possible to perform accurate temperature measurement while eliminating the influence of contamination or the like.

In the initialization step S20 , the phase change (amorphization) occurs by heating and rapidly cooling the phase change film MW2 , so that the temperature history of the phase change film MW2 can be initialized. Accordingly, the temperature measurement substrate MW can be repeatedly used for temperature measurement. Also, temperature measurement can be performed using the phase change film MW2 that can be initialized by the initialization step S20, so even after the phase change film is used for temperature measurement several times, the sensitivity and accuracy of temperature measurement will not deteriorate, and the temperature can be maintained. The accuracy of the measurement.

Furthermore, since the change in sheet resistance due to the initialization temperature of the phase change film MW2 and the heating temperature of the process temperature measurement heating step S32 depends on the composition of the phase change film MW2, it is not necessary to calculate the temperature again. That is, it is not necessary to calibrate temperature and sheet resistance every time temperature is measured. In addition, it is not necessary to prepare a new measurement substrate every time the temperature is measured. Therefore, temperature measurement can be performed quickly, and the workability and cost of temperature measurement can be improved.

A cover film MW3 is laminated on the phase change film MW2. Thereby, even if the heat treatment that should be carried out for temperature measurement in the process temperature measurement and heating step S32 is a treatment that will cause damage to the surface of the phase change film MW2 such as plasma treatment, it will not affect the phase change film MW2, and can be accurately performed. The temperature measurement. Furthermore, if the resistance value of the cover film MW3 is sufficiently higher than the resistance value of the phase change film MW2 measured in the sheet resistance measuring step S33, the change in the sheet resistance of the phase change film MW2 can be controlled independently of the resistance value of the cover film MW3. Quantity is measured.

In the first embodiment, in the thin film forming method in the subsequent step S40, film formation can be performed under set conditions for uniform film formation characteristics based on the temperature measured using the temperature measurement substrate MW which is a temperature measurement device. Thereby, in the film-forming process on the substrate 10 in the subsequent step S40, the in-plane temperature distribution can be made uniform, and the in-plane uniformity of film-forming characteristics such as film thickness, resistance value, and composition can be improved.

In addition, in 1st Embodiment, the sheet resistance accompanying a phase change was measured about the phase change film MW2, and the change amount of the measured sheet resistance was converted into the temperature change amount. The present invention does not limit this method. For example, as shown in FIG. 5 , the change amount of the optical refractive index or the extinction coefficient of the phase change film MW2 can also be measured, and the change amount can be converted into the change amount of temperature.

Furthermore, FIG. 4 shows an example of a calibration curve according to the relationship between the sheet resistance and the temperature change of the phase change film MW2 with different compositions. In FIG. 4 , MW2-1, MW2-2, MW2-3, and MW2-4 represent phase change film MW2 with different compositions, respectively. In addition, Fig. 5 shows an example of calibration data (curve) according to the relationship between the refractive index (n) and extinction coefficient (k) of the phase change film MW2 at a wavelength of 1550 nm and the temperature change.

Hereinafter, a temperature measuring method, a temperature measuring device, and a thin film forming method according to a second embodiment of the present invention will be described based on the drawings.

Fig. 6 is a schematic cross-sectional view of a temperature-measuring substrate showing an example of a temperature-measuring device according to a second embodiment. The second embodiment is different from the above-mentioned first embodiment in terms of the phase change film. The corresponding components of the first embodiment and the second embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the temperature measurement substrate MW of the second embodiment, as shown in FIG. 6 , the phase change film MW2a, the phase change film MW2b, and the cover film MW3 are laminated on the substrate MW1.

The phase change film MW2a and the phase change film MW2b are formed on the whole surface of the board|substrate MW1. The phase change film MW2a and the phase change film MW2b are chalcogenide-based materials represented by GST (alloy layer mainly composed of Ge, Sb, and Te) which is a material capable of reversibly changing between an amorphous phase and a crystalline phase , and materials similar to chalcogenide-based materials. Here, the GST film has a composition in which a phase change region exists at 100°C to 600°C. Sheet resistance and optical refractive index of GST film change with phase change. The composition ratio of the phase change film MW2a and the composition ratio of the phase change film MW2b are different from each other.

As shown in FIG. 6 , the phase change film MW2 a and the phase change film MW2 b are respectively formed on different regions of the substrate MW1 . The phase change film MW2a and the phase change film MW2b have the same film thickness as each other. In the substrate MW1 shown in FIG. 6, the region where the phase change film MW2a is formed and the region where the phase change film MW2b is formed are adjacent to each other. The region where the phase change film MW2a is formed and the region where the phase change film MW2b is formed may also be formed in a state of being separated from each other.

The phase change film MW2a and the phase change film MW2b are the same as the phase change film MW2 of the first embodiment, and are made of GST (mainly Ge, Sb, Te) as a material capable of reversibly changing between an amorphous phase and a crystalline phase. Alloy layer of composition) represented by chalcogenide-based materials, and materials similar to chalcogenide-based materials.

The phase change temperatures of the phase change film MW2a and the phase change film MW2b are different from each other. That is, the composition ratio of the phase change film MW2a is different from the composition ratio of the phase change film MW2b. The composition ratio of the phase change film MW2a and the phase change film MW2b is set so that a change in the sheet resistance capable of detecting the set measurement temperature occurs by heating. The composition ratio of the phase change film MW2a and the composition ratio of the phase change film MW2b are set based on the temperature-sheet resistance curve shown in FIG. 4 .

The phase change film MW2a and the phase change film MW2b are formed so as to have an equal composition ratio over the entire area of each region. In addition, the phase change film MW2a and the phase change film MW2b of the second embodiment are formed so that the composition distribution in the entire surface of each region is equal. Furthermore, as described below, the phase change film MW2a and the phase change film MW2b may also be formed to have different composition ratios in the direction along the surface of the substrate MW1. In addition, both the phase change film MW2a and the phase change film MW2b are formed so as to have an equal composition ratio over the entire length in the film thickness direction.

The phase change film MW2a and the phase change film MW2b are the same as the phase change film MW2 of the first embodiment, and can have a film thickness of 0.5 nm to 1000 μm, more preferably 1 nm to 1000 nm.

The cover film MW3 of the second embodiment is laminated on the entire surfaces of the phase change film MW2a and the phase change film MW2b. The cover film MW3 is laminated on the entire surface of the substrate MW1. The surface of the cover film MW3 is the front MWa which is the temperature measuring surface corresponding to the processing surface 10 a of the substrate 10 .

In the second embodiment, the surface of the substrate MW1 has a region where the phase change film MW2a is formed and a region where the phase change film MW2b is formed. The temperature set in each of the region of the phase change film MW2a and the region of the phase change film MW2b can be detected. Thereby, the temperature-measuring substrate MW of the second embodiment can have regions capable of measuring different temperatures, respectively.

Thus, different temperatures can be measured in specific regions of the substrate 10 respectively. Furthermore, different temperatures can be measured only by setting the composition of the phase change films MW2a and MW2b formed on the substrate MW1.

In the second embodiment, for example, a relatively high temperature of about 50° C. can be measured at the center position in the radial direction of the base body 10 . Furthermore, it may be possible to accurately measure a relatively lower temperature at the radially outer side of the base body 10 , that is, at the peripheral position than at the central position of about 50°C. In this case, the phase change film MW2a is formed at the radially central position of the temperature measuring substrate MW, and the phase change film MW2b is formed at the radially outer side of the temperature measuring substrate MW, that is, at the peripheral position.

In the second embodiment, two different temperature measurements can be performed using two phase change films having different compositions. Different temperatures may be measured in three or more regions using a phase change film having different composition ratios in three or more regions.

Furthermore, in the second embodiment, although two different temperature measurements can be performed in different regions, it is also possible to measure a continuously changing temperature. In this case, instead of a configuration using a phase change film having a different composition ratio for each region, a configuration in which the composition ratio gradually changes in a direction along the surface of the substrate MW1 may be used. In this case, in the calibration step S10 , obtaining the temperature-sheet resistance relationship will become a little more complicated, but it is easy to measure the required temperature in a specific area.

Hereinafter, a temperature measuring method, a temperature measuring device, and a thin film forming method according to a third embodiment of the present invention will be described based on the drawings.

7 is a schematic cross-sectional view showing a temperature measuring substrate as an example of a temperature measuring device according to a third embodiment. The third embodiment is different from the above-mentioned first and second embodiments in terms of the phase change film. Components corresponding to those of the first and second embodiments described above and those of the third embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the temperature measuring substrate MW of the third embodiment, unlike the first and second embodiments, as shown in FIG. 7 , the phase change film MW2c is locally formed on the substrate MW1. In the temperature measurement substrate MW of the third embodiment, the region where the phase change film MW2c is formed is a temperature measurement region. Other configurations of the substrate MW for temperature measurement are the same as those of the substrate 10 processed in the process temperature measurement heating step S32. Thereby, there are few differences in the configuration other than the part where temperature measurement is to be performed, and more accurate temperature measurement can be performed at a specific position.

The phase change film MW2c is set to be a film made of the same material as that of the phase change film MW2 of the first embodiment. The phase change film MW2c of the third embodiment can be formed only at the radially central position of the base body 10, for example. Alternatively, the phase change film MW2c of the third embodiment may be formed only on the outer side in the radial direction of the base body 10 , that is, at the peripheral position.

Furthermore, the phase change film MW2c of the third embodiment may be formed intermittently in a plurality of regions instead of being formed in one place. In this case, the composition ratio of the phase change film MW2c formed in several regions may mutually be the same. Like the second embodiment, the composition ratio of the phase change film MW2c formed in a plurality of regions may be different from each other.

The cover film MW3 of the third embodiment is laminated on the entire surface of the region where the phase change film MW2 is formed and the region where the phase change film MW2 is not formed. The cover film MW3 is laminated on the entire surface of the substrate MW1. The surface of the cover film MW3 is the front MWa which is the temperature measuring surface corresponding to the processing surface 10 a of the substrate 10 . Furthermore, the capping film MW3 can also be formed only in the area where the phase change film MW2 is formed and around the area where the phase change film MW2 is formed.

In the third embodiment, the same effects as those of the above-mentioned embodiment can be exhibited. Furthermore, in the third embodiment, there is an effect that the temperatures of different materials can be directly measured in the device region on the substrate that will eventually become a device.

Hereinafter, a temperature measuring method, a temperature measuring device, and a thin film forming method according to a fourth embodiment of the present invention will be described based on the drawings.

8 is a schematic cross-sectional view showing a temperature measuring substrate as an example of a temperature measuring device according to a fourth embodiment. The fourth embodiment is different from the above-mentioned first to third embodiments in terms of the insulating film. The structures corresponding to those of the first to third embodiments described above and those of the fourth embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the substrate MW for temperature measurement of the fourth embodiment, as shown in FIG. 8 , an insulating film MW4 is laminated between the substrate MW1 and the phase change film MW2 . The insulating film MW4 is formed so as not to affect the local characteristics of the substrate MW1 when the sheet resistance measurement of the phase change film MW2 is performed. The insulating film MW4 is, for example, a silicon oxide film, a silicon nitride film, a hafnium oxide film, a hafnium nitride film, silicon oxycarbide, silicon carbide, fluorine-doped silicon oxide, aluminum oxide, or aluminum nitride. In addition, the insulating film MW4 of the fourth embodiment may have a film thickness of 0.5 nm to 10000 μm, more preferably 10 nm to 1000 nm. The insulating film MW4 is laminated on the entire surface of the substrate MW1.

In the substrate MW for temperature measurement of the fourth embodiment, even if the substrate MW1 on which the phase change film MW2 is laminated has an in-plane conductivity distribution on the surface of the substrate MW1 that affects the measurement of the sheet resistance of the phase change film MW2, it is possible to prevent It affects the sheet resistance measurement in the sheet resistance measurement step S33. For example, even if the substrate MW1 is not a bare silicon substrate but is formed with wiring, N regions, P regions, etc., since the wiring or regions are covered with the insulating film MW4, it is possible to prevent the influence on the sheet resistance measurement in the sheet resistance measurement step S33.

In the fourth embodiment, the same effects as those of the above-mentioned embodiment can be exhibited. Furthermore, in the fourth embodiment, the effect that measurement can be performed even on an electroconductive substrate or an electroconductive film can be exhibited.

Hereinafter, a temperature measuring method, a temperature measuring device, and a thin film forming method according to a fifth embodiment of the present invention will be described based on the drawings.

9 is a schematic cross-sectional view showing a temperature measuring substrate as an example of a temperature measuring device according to a fifth embodiment. The fifth embodiment is different from the above-mentioned first to fourth embodiments regarding the position of the phase change film. Components corresponding to the above-mentioned first to fourth embodiments are denoted by the same reference numerals, and description thereof will be omitted.

In the temperature measurement substrate MW of the fifth embodiment, as shown in FIG. 9 , the phase change film MW2 is formed on the back surface of the substrate MW1 opposite to the front surface MWa which is the temperature measurement surface corresponding to the processing surface 10 a of the substrate 10 . In the temperature measurement substrate MW of the fifth embodiment, the cover film MW3 is not formed as shown in FIG. 9 . The reason is that the surface on which the phase change film MW2 is formed is not the front MWa which is the plasma treated surface, so the plasma does not affect the phase change film MW2. Thereby, there is no need to protect the phase change film MW2.

Moreover, the surface on which the phase change film MW2 is formed is the surface of the substrate MW for temperature measurement that is in contact with the platform 15. Therefore, in the fifth embodiment, strictly speaking, the measured temperature distribution is the surface of the substrate MW for temperature measurement and the platform. 15 In-plane temperature distribution of the connected surfaces. For example, when the substrate MW1 is a bare wafer including a silicon single crystal, the temperature distribution of the front MWa which is the surface to be processed can also be measured by performing correction corresponding to the thickness of the silicon wafer.

Also, when the substrate MW1 is, for example, a glass substrate with a thickness of 1 mm or less, it is possible to directly measure a temperature distribution that can almost approximate the temperature of the front MWa. In this case, it can be applied to the time of temperature measurement in a vertical processing apparatus that processes the substrate 10 as a glass substrate parallel to the vertical direction.

In addition, in the fifth embodiment, for example, when the substrate 10, which is a large glass substrate for FPD, is the measurement object, the temperature measurement substrate MW also needs to be of the same size, but the phase change film can also be formed locally on the large substrate. MW2.

In the fifth embodiment, the same effects as those of the above-mentioned embodiment can be exhibited. Furthermore, in the fifth embodiment, since there is no lateral heat propagation through the base material, it is possible to more significantly evaluate the difference in temperature distribution.

In addition, also in 5th Embodiment, the shape similar to 2nd - 4th Embodiment can be employ|adopted. Specifically, each of the configurations of the above-described embodiments may be arranged on the rear surface. For example, as shown in FIG. 10, the phase change film MW2 is formed on the back side of the substrate MW1, which is opposite to the front MWa of the temperature measuring surface corresponding to the processing surface 10a of the substrate 10, and is laminated between the substrate MW1 and the phase change film MW2. Insulating film MW4. Here, the cover film MW3 may be formed, and the cover film MW3 may not be formed.

Moreover, it is good also as the structure which individually combined each structure in each said embodiment.

1: Plasma CVD device 2: Vacuum chamber 2a: film-forming space 4: electrode flange 5: Shower board 5a: Noodles 6: Gas outlet 7: Gas inlet tube 9: RF power supply 10: matrix 10a: Treatment surface 15: Second electrode 15a: face 16: heater 17: Second power supply 21: Process gas supply department 24: space 25: Pillar 27: exhaust pipe 28: Vacuum pump 30: ground wire 41: upper wall 42: Gas inlet 43: Peripheral wall 81: Insulation flange 101: Processing room MW: Substrate for temperature measurement MW1: Substrate MW2, MW2a, MW2b, MW2c: phase change film MW3: cover film MW4: insulating film MWa: Front T/S:Interval

Fig. 1 is a schematic sectional view showing a temperature measuring device according to a first embodiment of the present invention. Fig. 2 is a schematic sectional view showing a device for measuring temperature in the temperature measuring method according to the first embodiment of the present invention. Fig. 3 is a flowchart showing a temperature measuring method according to the first embodiment of the present invention. Fig. 4 is a graph showing the characteristics of the phase change film in the temperature measuring device according to the first embodiment of the present invention. Fig. 5 is a graph showing the characteristics of the phase change film in the temperature measuring device according to the first embodiment of the present invention. Fig. 6 is a schematic sectional view showing a temperature measuring device according to a second embodiment of the present invention. Fig. 7 is a schematic sectional view showing a temperature measuring device according to a third embodiment of the present invention. Fig. 8 is a schematic sectional view showing a temperature measuring device according to a fourth embodiment of the present invention. Fig. 9 is a schematic sectional view showing a temperature measuring device according to a fifth embodiment of the present invention. Fig. 10 is a schematic cross-sectional view showing another example of the temperature measuring device according to the fifth embodiment of the present invention.

MW: Substrate for temperature measurement

MW1: Substrate

MW2: phase change film

MW3: cover film

MWa: front

Claims (15)

A method for measuring temperature, which involves heat-treating a temperature-measuring substrate on which a phase-change film whose physical quantity changes according to a change in temperature is laminated, The measured physical quantity is obtained by measuring the physical quantity of the above-mentioned phase change film after heat-treating the above-mentioned temperature-measuring substrate, Based on the measured physical quantity and the relationship between the physical quantity and temperature obtained in advance, the temperature and temperature distribution of the temperature-measuring substrate during the heat treatment of the temperature-measuring substrate are obtained. Such as the temperature measurement method of claim 1, wherein The above-mentioned measured physical quantity and the above-mentioned physical quantity of the above-mentioned relationship are any one of sheet resistance, optical refractive index, and extinction coefficient. Such as the temperature measurement method of claim 1 or 2, wherein Initialize the temperature history of the above-mentioned phase change film. Such as the temperature measurement method of claim 3, wherein When initializing the above-mentioned temperature history of the above-mentioned phase change film, heating the phase change film to initialize the temperature history of the phase change film, and The phase change of the phase change film is caused by rapidly cooling the phase change film. Such as the temperature measurement method of claim 3, wherein In the heat treatment of the temperature measuring substrate, the temperature measuring substrate having the phase change film whose temperature history has been initialized is used. The temperature measurement method according to claim 3, wherein the temperature measurement substrate having the phase change film whose temperature history has been initialized is reused. The temperature measurement method according to claim 1 or 2, wherein the relationship between the physical quantity and temperature of the surface of the substrate for temperature measurement is obtained in advance. Such as the temperature measurement method of claim item 7, wherein When the relationship between the physical quantity and temperature of the surface of the above-mentioned temperature measuring substrate is obtained in advance, The above-mentioned substrate for temperature measurement is heated to a specific temperature and maintained at a constant temperature, The physical quantity of the above-mentioned phase change film on the above-mentioned temperature measurement substrate is measured, Based on the above-mentioned measured physical quantity of the above-mentioned phase change film obtained by measuring the physical quantity of the above-mentioned phase change film obtained by heating the above-mentioned temperature-measuring substrate to a specific attainable temperature and maintaining it in a constant temperature state. , and the relationship between the physical quantity and temperature of the above-mentioned phase change film is derived. Such as the temperature measurement method of claim 4, wherein The above-mentioned phase change film is formed of a chalcogenide-based alloy capable of reversibly changing between an amorphous phase and a crystalline phase, The heating temperature for heating the phase change film to initialize the temperature history is set to be higher than the temperature range in the heat treatment of the temperature measuring substrate on which the phase change film is laminated. Such as the temperature measuring method of claim item 9, wherein The above-mentioned phase change film is formed of an alloy mainly composed of any two or more selected from Ge, Sb, and Te, The temperature range in the heat treatment of the substrate for temperature measurement on which the phase change film is laminated is 100°C to 600°C. A temperature measurement device comprising a substrate for temperature measurement on which a phase change film is laminated, The above-mentioned phase change film is formed of a chalcogenide-based alloy, and the chalcogenide-based alloy is any two or more selected from Ge, Sb, and Te, which are materials capable of reversibly changing between an amorphous phase and a crystalline phase. main component. Such as the temperature measuring device of claim 11, wherein The temperature measuring substrate includes a cover film laminated on the phase change film. Such as the temperature measuring device of claim 11 or 12, which An insulating film provided between the temperature measuring substrate and the phase change film is provided. A method of forming a thin film using a temperature distribution in a substrate surface set based on a temperature measured by the temperature measuring method in any one of claims 1 to 10 to form a film. A method of forming a thin film using a temperature distribution in a substrate surface set based on a temperature measured using the temperature measuring device according to any one of Claims 11 to 13.

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