JP2016121384A - Vapor deposition apparatus and vapor deposition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vapor deposition apparatus and a vapor deposition method which are able to more precisely measure the thickness of a vapor-deposited film.SOLUTION: A vapor deposition apparatus evaporates a material 8, which has been vaporized, on the surface of a substrate 4 disposed in a chamber 1. The vapor deposition apparatus includes: a vapor deposition source 3 for vaporizing the material 8; a pipe part 2 which has an opening part 20 connected to the vapor deposition source 3 to supply a vaporized material to the substrate 4, and which has windows 18, 19 for making light 27 go into, pass through, and go out of the vaporized material; a valve 6 which is disposed inside the pipe part 2 to adjust the flow rate of the vaporized material flowing in the pipe part 2; and a heating control part 15 which controls the heating of the vapor deposition source 3, the valve 6, and the pipe part 2 to form a temperature gradient where the temperature of the vicinity of the opening part 20 is higher than that of a valve disposition part of the pipe part 2.SELECTED DRAWING: Figure 1A

Description

  The present disclosure relates to a vapor deposition apparatus and a vapor deposition method for vaporizing a vaporized material on a substrate in manufacturing a thin film such as an organic EL (Electro Luminescence) element.

  Vapor deposition equipment deposits vaporized material on the surface of a substrate by placing the material and the substrate in a chamber, heating the material, melting the material and then evaporating or sublimating the material. The material is deposited on the substrate.

  In recent years, organic devices such as displays, lighting, solar cells, and semiconductors using organic materials have been developed. Film formation of these organic layers using organic materials is generally performed using a vapor deposition apparatus as described above. The film thickness control of the organic layer or the like in the vapor deposition apparatus needs to be performed with high accuracy so as to obtain a predetermined film thickness from the viewpoint of efficiency. In such a film thickness measurement method used for film thickness control, a crystal resonator may be used (see, for example, Patent Document 1).

  Therefore, a conventional film thickness measurement method using a crystal resonator will be described with reference mainly to FIG. FIG. 6 is a schematic cross-sectional view of a conventional vapor deposition apparatus using a crystal resonator. The vacuum chamber 101 can be evacuated to a vacuum state by being evacuated by the vacuum pump 105. Inside the vacuum chamber 101, a substrate 104 on which film formation is performed is disposed at the upper part, and a crucible 107 is disposed at the lower part so as to face the substrate 104.

  The crucible 107 can be heated by controlling the heating element control unit 115 such as a power source connected to the heating element 109 to generate heat. Furthermore, in the upper part in the vacuum chamber 101, for example, a quartz crystal (QCM, Quartz Crystal Microbalance) 128 made of quartz is disposed adjacent to the substrate 104. As a result, a thin film is also deposited on the crystal resonator 128.

  Here, the film thickness of the thin film deposited on the crystal unit 128 is indirectly obtained from a change in the natural frequency of the crystal unit 128 that decreases according to the deposition amount. There is a certain relationship between the film thickness of the thin film deposited on the crystal resonator 128 obtained in this way and the film thickness of the thin film deposited on the substrate 104.

  Therefore, the film thickness of the thin film deposited on the substrate 104 can be obtained from the measurement result of the natural frequency of the crystal resonator 128.

  Therefore, by measuring the natural frequency of the crystal resonator 128, the film thickness of the thin film deposited on the substrate 104 is indirectly acquired, and the heating element controller 115 is obtained based on the acquired film thickness of the thin film. The analysis unit 113 is provided for sending the instruction signal. The heating element control unit 115 controls the heating temperature of the heating element 109 of the crucible 107. Therefore, based on the instruction signal from the analysis unit 113 to the heating element control unit 115, the heating temperature of the heating element 109 of the crucible 107 can be controlled by the heating element control unit 115, and the thin film formed on the substrate 104 can be controlled. The film thickness is controlled.

  Of course, the object used for measuring the film thickness does not have to be the crystal resonator 128, and instead of the crystal resonator 128, a dummy substrate in which film formation is performed under substantially the same conditions as in the case of the substrate 104. It may be.

  Next, in the film thickness measurement method used for such film thickness control, the concentration of the vaporized material 108 may be optically detected using an optical detection means (for example, see Patent Document 2). .)

  Accordingly, a conventional film thickness measurement method in which the concentration of the vaporized material 108 is optically detected using an optical detection means will be described with reference mainly to FIG. FIG. 7 is a schematic sectional view of a conventional vapor deposition apparatus in which the concentration of the vaporized material 108 is optically detected using an optical detection means. The vacuum chamber 101 can be evacuated to a vacuum state by being evacuated by the vacuum pump 105. Inside the vacuum chamber 101, a substrate 104 on which film formation is performed is disposed above, and a heated vapor deposition head 150 is disposed below the substrate 104 so as to face the substrate 104.

  The vapor deposition head 150 is connected to the vapor deposition source 107, and the material 108 evaporated from the heated vapor deposition source 107 passes through the vapor deposition head 150 and reaches the substrate 104. The vapor deposition head 150 is provided with windows 118 and 119 for allowing light 127 to pass therethrough, and windows 116 and 117 for allowing the light 127 to pass are also provided on both side surfaces of the vacuum chamber 101. A light source 111 and a detector 112 are arranged so as to pass through the windows 116, 117, 118, and 119. Light 127 from the light source 111 is received by the detector 112 through the vaporized material 108 in the vapor deposition head 150. There is a certain relationship between the concentration of the vaporized material 108 that is indirectly measured from the comparison between the light at the time of light emission and the light at the time of light reception, and the film thickness of the thin film deposited on the substrate 104.

  For this reason, the film thickness of the thin film deposited on the substrate 104 can be obtained from the measurement result of light at the time of light reception.

  Of course, the comparison between the light during light emission and the light during light reception described above is performed when the vaporized material 108 is present in the vapor deposition head 150. However, in order to obtain the film thickness of the thin film deposited on the substrate 104 by the same comparison, the same measurement result for the case where the vaporized material 108 does not exist in the vapor deposition head 150 is prepared in advance. Used when obtaining film thickness.

  Therefore, an analyzer 113 is provided that measures light at the time of light reception, indirectly acquires the film thickness of the thin film deposited on the substrate 104, and sends an instruction signal to the deposition source 107. The evaporation source 107 can heat the vapor deposition source 107 based on an instruction signal from the analysis unit 113 to control the evaporation amount of the material from the vapor deposition source 107 and the like, and is a thin film formed on the substrate 104. The thickness is controlled.

JP 2005-325391 A JP 2012-046780 A

  However, in the above-described first conventional vapor deposition apparatus (see FIG. 6), the life of the crystal resonator 128 is not so long, so that the film thickness measurement is performed unless the crystal resonator 128 is frequently replaced. Is difficult to perform with high accuracy.

  Next, the second conventional vapor deposition apparatus (see FIG. 7) described above does not require frequent maintenance such as replacement of the crystal unit 128. However, the present inventor has noticed that the correlation between the light measurement result and the thickness of the thin film on the substrate fluctuates when the material 108 or the deposition rate is changed in the second conventional deposition apparatus. It was.

  Then, the present inventor changes the temperature of the piping unit 110 between the vapor deposition source 107 and the vapor deposition head 150 through which the vapor deposition source 107 or the vaporized material 108 passes in order to adjust the material or the vapor deposition rate. It has been analyzed that the cause is that the easiness of flow of the vaporized material 108 in the piping part 110 due to the thermal expansion of the 110 changes.

  That is, the vaporized material 108 passes through the piping unit 110 from the vapor deposition source 107, but when the temperature of the piping unit 110 changes, the distance of the piping unit 110 becomes longer due to thermal expansion of the piping unit 110. When the piping part 110 becomes longer, the vaporized material 108 becomes difficult to flow, so even if the measurement result of light at the vapor deposition head 150 does not change, the correlation between the measurement result and the film thickness of the thin film on the substrate varies. It will end up. Therefore, even if the measurement result of light is kept constant, it is difficult to obtain a target film thickness.

  In view of the above-described conventional problems, an object of the present disclosure is to provide a vapor deposition apparatus and a vapor deposition method that can perform film thickness measurement of a vapor deposition film with higher accuracy.

A vapor deposition apparatus according to the present disclosure is a vapor deposition apparatus that vaporizes a vaporized material on a surface of a substrate disposed inside a chamber,
A vapor deposition source for vaporizing the material;
Connected to the vapor deposition source, and having an opening for supplying the vaporized material from the vapor deposition source to the substrate, allows light to enter the vaporized material, pass through the vaporized material, and emit light. A piping part having a window for causing
A valve that is arranged in the pipe part and flows through the pipe part from the vapor deposition source, and adjusts the flow rate of the vaporized material;
Heating of the vapor deposition source, the valve, and the piping portion so that the piping portion has a temperature gradient such that the temperature in the portion near the opening is higher than the portion where the valve is disposed in the piping portion. A heating control unit for controlling

  According to the above aspect of the present disclosure, for example, it is possible to perform film thickness measurement of a deposited film with higher accuracy.

Schematic sectional view of the vapor deposition apparatus of the first embodiment Flowchart of the vapor deposition method by the vapor deposition apparatus of the first embodiment. Schematic sectional view of the vapor deposition apparatus of the second embodiment Schematic sectional view of the vapor deposition apparatus of the third embodiment Schematic sectional view of the vapor deposition apparatus of the fourth embodiment Schematic sectional view of the vapor deposition apparatus of the fifth embodiment Schematic cross-sectional view of a vapor deposition apparatus that uses a conventional crystal unit A schematic cross-sectional view of a conventional vapor deposition apparatus in which the concentration of vaporized material is optically detected using an optical detection means

  Hereinafter, a vapor deposition apparatus and a vapor deposition method according to an embodiment of the present disclosure will be described in detail with reference to the drawings. In the drawings, substantially the same members or devices are denoted by the same reference numerals.

(First embodiment)
First, the configuration of the vapor deposition apparatus of the first embodiment will be described with reference mainly to FIGS. 1A and 1B. Here, FIG. 1A is a schematic longitudinal sectional view of the vapor deposition apparatus of the first embodiment. FIG. 1B is a flowchart of a vapor deposition method using a vapor deposition apparatus.

  This vapor deposition apparatus is a vapor deposition apparatus that vaporizes the vaporized material 8 on the surface of the substrate 4 disposed inside the vacuum chamber 1. Specifically, this vapor deposition apparatus includes a vacuum chamber 1, a pipe section 2, a vapor deposition source 3, a conductance valve 6, and an optical concentration measuring device 100.

  The vapor deposition source 3 vaporizes the material 8 in the vacuum chamber 1.

  The conductance valve 6 adjusts the flow rate of the vaporized material 8.

  The optical density measuring device 100 makes light incident on the pipe part 2, receives light emitted from the pipe part 2 through the vaporized material 8 in the pipe part 2, and the concentration of the vaporized material 8. Is measured optically.

  The pipe section 2 supplies the vaporized material 8 from the vapor deposition source 3 into the vacuum chamber 1 through the conductance valve 6 and passes through the optical density measuring device 100 in the pipe section 2 at the upper end thereof. An opening 20 for spraying the material 8 onto the substrate 4 is provided.

  The optical density measuring device 100 is disposed in the pipe portion 2 between the conductance valve 6 and the opening 20. The piping part 2 can be set at a plurality of locations, and is provided with a temperature gradient such that the temperature on the opening 20 side is higher than the conductance valve 6 side. As an example of the temperature gradient, the temperature gradient also varies depending on the material or the pipe length, but the temperature gradient is set to 50 ° C. or less with respect to the setting of 200 to 500 ° C. In addition, when a temperature gradient is provided over a plurality of locations, the temperature gradient at each location may be equalized.

  According to this vapor deposition apparatus, as described above, the pipe part 2 is provided with a temperature gradient such that the temperature on the opening 20 side is higher than the conductance valve 6 side, so that the pipe part can be changed by changing the temperature gradient. It is possible to adjust the easiness of the flow of the gas 2 and to correct the correlation between the measured value of the concentration of the vaporized material 8 and the film thickness of the thin film of the substrate, and to control the film thickness with high accuracy. Here, when correcting the correlation between the measured value of the concentration of the vaporized material 8 and the film thickness of the thin film on the substrate, for example, in the analysis unit 13 described later, the correlation is previously set for each temperature setting of the piping unit 2. By acquiring a linear temperature gradient and using it, the correlation can be maintained even if the temperature setting is changed. By correcting in this way, a desired film thickness can be obtained with high accuracy from the corrected correlation.

  Below, the structural member which comprises this vapor deposition apparatus is demonstrated in detail.

<Vacuum chamber>
The vacuum chamber 1 is configured to have a reverse convex shape in the vertical cross section, and the vacuum chamber 1 can be depressurized to a vacuum state by being evacuated by the vacuum pump 5.

  Inside the vacuum chamber 1, a substrate 4 made of glass or silicon with a film formation surface on which film formation is performed on the lower side is disposed at an upper end portion thereof.

<Deposition source>
In the lower part of the vacuum chamber 1, a vapor deposition source 3 having a crucible 7 for vaporizing the material 8 by evaporation or sublimation is disposed. A material 8 is held and filled in the crucible 7. The material 8 is vaporized by the crucible 7.

  The material 8 is an arbitrary vapor deposition material, and is, for example, an organic material such as an organic electroluminescence material or an inorganic material.

<Piping section>
At the upper part of the vapor deposition source 3, a cylindrical pipe part 2 that transports the evaporated material 8 to the central part in the chamber 1 is installed. An opening 20 for spraying the vaporized material 8 onto the substrate 4 is provided at the upper end of the pipe portion 2. The opening 20 is located near the center in the chamber 1. The piping unit 2 transports the vaporized material 8 from the vapor deposition source 3 to the opening 20, that is, the central portion in the chamber 1. Furthermore, a pair of transmission windows 18 and 19 are provided on the side portion of the pipe portion 2 so as to allow light to enter and exit, thereby enabling optical density measurement.

  On the side of the lower part of the vacuum chamber 1, at the same height as the transmission windows 18 and 19 of the pipe section 2, there are provided a pair of transmission windows 16 and 17 that are opposed to allow light 27 to enter and exit. .

<Conductance valve>
In the pipe section 2, a conductance valve 6 that adjusts the flow rate of the vaporized material 8 that is supplied from the vapor deposition source 3 and is guided to the opening 20 is provided. The opening degree of the conductance valve 6 is controlled by a conductance valve opening degree control unit 14 disposed outside the vacuum chamber 1.

<Heating element>
In the vapor deposition source 3 and the piping part 2, heating elements 91, 92, 93, 94 as examples of a heating device are provided outside. The heating element 91 is disposed on the bottom surface and the side surface of the vapor deposition source 3. The heating element 92 is disposed on the outer side surface of the portion of the piping part 2 in which the conductance valve 6 is disposed. The heating elements 93 are arranged on the outer side surfaces around the transmission window 18 and the transmission window 19 in the pipe portion 2. The heating element 94 is disposed on the outer side surface of the upper end near the opening 20 of the pipe 2.

  The heating elements 91, 92, 93, and 94 are connected to a heating power source (not shown) and a heating element control unit 15 as an example of a heating control unit. The heating element control unit 15 supplies a voltage from the heating power source. By heating the heating elements 91, 92, 93, 94 while controlling the application, not only the crucible 7 but also the pipe part 2, the conductance valve 6 and the wall of the vapor deposition source 3 can be heated.

  Each heating element 91, 92, 93, 94 can be controlled independently.

<Optical density measuring device>
The optical density measuring device 100 includes a light source 11 disposed outside the vacuum chamber 1, a detector 12 disposed outside the vacuum chamber 1, and light 27 disposed outside the vacuum chamber 1 and received by the detector 12. And an analysis unit (calculation unit) 13 for analyzing the above.

  As the light source 11, the absorption wavelength of the vapor deposition material, such as a semiconductor laser or lamp in the infrared region, visible light region, or ultraviolet region, a white lamp such as a xenon lamp, a deuterium lamp, a holocathode lamp, or a tunable dye laser. A light source suitable for the region may be used.

  The analysis unit 13 is electrically connected to the heating element control unit 15 and the conductance valve opening control unit 14. The light 47 received by the detector 12 is analyzed by the analysis unit 13 and an instruction signal for the heating element control unit 15 or the conductance valve opening control unit 14 is generated as necessary. The heating element control unit 15 can control the heating temperatures of the heating elements 91, 92, 93, and 94 of the crucible 7 based on the instruction signal from the analysis unit 13. The conductance valve opening control unit 14 can control the opening of the conductance valve 6 based on the instruction signal from the analysis unit 13.

  Light 27 from the light source 11 passes through the transmission window 16 of the chamber 1 along the direction perpendicular to the flow direction of the vaporized material 8 (left-right direction in FIG. 1A) and enters the transmission window 18 of the pipe section 2. To do. Then, the light 27 traverses the vaporized material 8 in the pipe part 2, is emitted from the transmission window 19 of the opposite pipe part 2 to the outside of the pipe part 2, passes through the transmission window 17 of the chamber 1 and passes through the chamber 1. The light is emitted outside and received by the detector 12.

  The light 27 may be subjected to multiple reflection using a mirror instead of the transmission window 19 or after passing through the transmission window 16.

  Further, the light 27 may be incident and output in any direction with respect to the flow direction of the vaporized material 8.

  The optical density measuring device 100 causes the light 27 from the light source 11 to enter the chamber 1 and the pipe portion 2 in order and pass through the vaporized material 8. Then, the light 27 changed by light absorption, light emission, and scattering of the gas molecules is sequentially emitted from the pipe portion 2 and the chamber 1, received by the detector 12, and the received light 27 is analyzed by the analysis portion 13. To do. As described above, when the pipe part 2 has a small cross-sectional area in the direction perpendicular to the material flow of the pipe part 2 with respect to the space of the chamber 1, the vaporized material 8 is contained in the pipe part 2. Small decrease in concentration. Therefore, the concentration of the gas molecules in the vaporized material 8 in the pipe portion 2 can be measured with high sensitivity and high accuracy by the optical concentration measuring device 100.

  As an analysis method in the analysis unit 13, for example, spectroscopic analysis, light absorption analysis, or emission analysis can be used.

  As a spectroscopic analysis method in the optical concentration measuring apparatus 100, for example, ultraviolet-visible spectroscopic analysis, fluorescence spectroscopic analysis, infrared spectroscopic analysis, or Raman spectroscopic analysis can be used.

  Next, referring to FIG. 1B, the operation of the vapor deposition apparatus of the first embodiment will be described, and an embodiment of the vapor deposition method of the present disclosure will also be described (the same applies to other embodiments described later). .)

  (Step S <b> 1) First, the crucible 7 of the vapor deposition source 3 is filled with the material 8 to be vapor deposited and set, and the substrate 4 is set above the vapor deposition source 3 in the vacuum chamber 1.

  (Step S2) Next, the vacuum pump 5 is operated to reduce the pressure so that the inside of the vacuum chamber 1 is in a vacuum state, and the heating element of the pipe section 2 and the conductance valve 6 is controlled by the heating element control section 15. The walls 92, 93, and 94 are caused to generate heat, and the walls of the pipe section 2 and the transmission windows 18 and 19 are controlled to be heated under a temperature gradient that will be described later to be heated to a predetermined temperature.

  (Step S3) When the vapor deposition source 3 and the crucible 7 are heated by the heating element 91 under the control of the heating element control unit 15, the material 8 melts and evaporates or sublimates to vaporize.

  (Step S4) The vaporized material 8 flies in the piping part 2 from the vapor deposition source 3 toward the opening 20 toward the vacuum chamber 1 having a low pressure due to the pressure gradient. When the vaporized material 8 reaches the opening 20 of the pipe part 2, it diffuses from the opening 20 into the central part and the upper part of the vacuum chamber 1 and reaches the surface of the substrate 4.

  (Step S <b> 5) The vaporized material 8 reaches the surface of the substrate 4 and is deposited in this manner, whereby vapor deposition can be performed on the surface of the substrate 4. During the vapor deposition process, basically, the opening is adjusted by the conductance valve 6 so that the amount of the material 8 to be vaporized (the concentration of the material 8) is always constant, and the material 8 is exposed to the surface of the substrate 4 for a predetermined time. Film formation is performed.

  (Step S6) The light 27 including the wavelength absorbed by the material 8 passes through the transmission window 16 of the vacuum chamber 1 and the transmission window 18 of the piping unit 2 from the light source 11, and is vaporized in the piping unit 2. Incident on material 8. Thereafter, the light passing through the vaporized material 8 and emitted from the vaporized material 8 passes through the transmission window 19 of the pipe section 2 and the transmission window 17 of the chamber 1, and is detected by the detector 12 outside the chamber 1. Receive light. The concentration of the vaporized material 8 from the light received by the detector 12 is optically measured by the analysis unit 13. Since the attenuation amount of the light 27 due to the absorption of the vaporized material 8 changes according to the concentration of the vaporized material 8, by measuring the attenuation amount of the light 27 by the analysis unit 13, the concentration of the vaporized material 8 can be reduced. The measured value can be indirectly measured by the analysis unit 13.

  (Step S7) Based on the measured value of the concentration of the vaporized material 8 obtained indirectly by the analysis unit 13, the measured value of the concentration of the vaporized material 8 and the thin film of the substrate 4 obtained in advance are obtained. Based on the correlation with the film thickness, the analysis unit 13 acquires the film thickness of the thin film of the substrate 4. At this time, for example, concentration measurement processing is performed for a predetermined time every predetermined time, an average value of a plurality of measured values is calculated, and based on the average value, the analysis unit 13 determines the thin film of the substrate 4. The film thickness may be acquired.

  (Step S8) The analysis unit 13 determines whether or not the obtained film thickness of the thin film of the substrate 4 is a desired film thickness. If the analysis unit 13 determines that the obtained thin film thickness of the substrate 4 is a desired film thickness, the conductance valve 6 is closed, or the shutter on the substrate side (not shown) is closed, and a series of End the process. On the other hand, if the analysis unit 13 determines that the obtained thin film thickness of the substrate 4 is less than the desired film thickness, the process proceeds to step S9.

  (Step S9) Next, when the amount of the material 8 to be vaporized during the vapor deposition process decreases, an adjustment process is required to maintain a certain amount of vapor deposition on the substrate 4. Therefore, the opening of the conductance valve 6 is adjusted by the conductance valve opening control unit 14 using the measurement value optically measured by the analysis unit 13. Alternatively, when the opening of the conductance valve 6 cannot be adjusted (for example, when the valve opening is 70% or more), the heating element 91 controls the vapor deposition source 3 under the control of the heating element controller 15. The measured value for the desired optical monitor is obtained. Alternatively, by using the measurement value optically measured by the analysis unit 13, the heating element control unit 15 controls the heating elements 91, 92, 93, 94, the vapor deposition source 3, the conductance valve 6, and the piping unit 2. Increase or decrease the temperature. Here, the latter temperature adjustment will be described. First, the analysis unit 13 determines whether temperature adjustment is necessary. Specifically, the analysis unit 13 determines whether the measured value of the concentration of the material 8 measured by the analysis unit 13 is equal to or less than the adjustment start threshold value. If the analysis unit 13 determines that the measured concentration value is not equal to or less than the adjustment start threshold value, the process returns to step S6, the vapor deposition process is continued as it is, and the concentration measurement process is performed at predetermined time intervals in step S6. Perform for a predetermined time. On the other hand, if the analysis unit 13 determines in step S9 that the measured concentration value is equal to or less than the adjustment start threshold, the amount of the material 8 to be vaporized has decreased too much. In step S10, the temperature adjustment is performed. Process.

  (Step S10) In the temperature adjustment process, for example, when at least the temperature of the vapor deposition source 3 is increased, or when the temperatures of the vapor deposition source 3, the conductance valve 6, and the pipe part 2 are increased, the pipe part 2 is thermally expanded. The pipe part 2 becomes longer, and the vaporized material 8 passing through the pipe part 2 is less likely to flow through the pipe part 2. Then, even if the concentration measured by the piping part 2 is constant, the film thickness on the substrate 4 becomes small, and the target film thickness cannot be obtained. Therefore, a temperature gradient is provided so that the heating elements 91, 92, 93, 94 generate heat under the control of the heating element control unit 15, and the temperature increases from the conductance valve 6 of the piping unit 2 toward the opening 20. (T94> T93 ≧ T92 below). By controlling in this way, the vaporized material 8 in the piping part 2 is an ascending airflow due to a temperature gradient, and the influence of difficulty in flowing can be reduced, and a target film thickness can be obtained. The inclination of the temperature gradient is determined by the analysis unit 13 in consideration of the difference between the film thickness acquired based on the measured value and the target film thickness, and an instruction signal is received from the analysis unit 13. What is necessary is just to send to the heat generating body control part 15. Further, by controlling the heating element control unit 15, the temperature gradient in the piping unit 2 is changed by increasing the temperature gradient as the temperature of the piping unit 2 increases through the heating elements 91, 92, 93, 94. Variations in the easiness of flow of the vaporized material 8 can be suppressed, and the correlation between the measured concentration value measured by the analysis unit 13 and the film thickness of the thin film on the substrate 4 can always be kept constant.

  Assuming that the set temperatures of the heating elements 91, 92, 93, and 94 are T91, T92, T93, and T94, respectively, for example, the temperature gradient of the set temperature is set by the following equation.

T94> T93 ≧ T92 ≧ T91
In addition, when correcting the correlation between the measured value of the concentration of the vaporized material 8 and the film thickness of the thin film of the substrate 4, or when the temperature of the vapor deposition source 3 is changed, the temperature of the pipe section 2 is adjusted to cause a temperature gradient. Is changed (in other words, when the temperature gradient of the pipe section 2 is changed for each temperature of the vapor deposition source 3), the following correction is performed. That is, for example, in the analysis unit 13, a temperature gradient such that the correlation is linear is acquired in advance for each temperature setting of the piping unit 2, and the correlation is used even if the temperature setting is changed by using the temperature gradient. Is preferably maintained. Thus, if the temperature gradient is increased as the set temperature is higher, the correlation between the substrate film thickness and the measurement value obtained by the optical density measuring device can be made linear, and therefore the film thickness can be controlled with high accuracy.

  According to this vapor deposition method, the temperature of the vapor deposition source 3, the conductance valve 6, and the piping unit 2 is decreased because the remaining amount of the material 8 is reduced by adjusting the opening degree of the conductance valve 6 or adjusting the temperature by the heating element control unit 15. Even if it is raised, the correlation between the optically measured value and the film thickness of the thin film of the substrate 4 does not vary, so that film formation with a desired film thickness can be performed with high accuracy.

  The adjustment of the present disclosure is more effective as the inner diameter of the pipe portion 2 is smaller and the distance is longer.

  Of course, in the first embodiment, the temperature change depends on the remaining amount of the material 8, but as another example of changing the temperature of the vapor deposition source 3 and the piping unit 2, after maintenance such as long-term stop or material replacement Various specific examples are conceivable, such as starting up the apparatus.

  An apparatus including the analysis unit 13, the conductance valve opening control unit 14, and the heating element control unit 15 is an example of a film formation condition control device of the present disclosure.

  In addition, when a plurality of materials are simultaneously formed, each material is provided with an optical concentration measuring device and a vapor deposition source corresponding to each material is provided, so that a plurality of materials are mixed in each vapor deposition source. Therefore, it is possible to measure the concentration of the gas molecules of the individual material, and hence the film thickness of the deposited film, with high sensitivity and high accuracy.

  Further, the substrate 4 may move or rotate, or the vapor deposition source 3 and the piping unit 2 may move or rotate.

  Further, the arrangement of the substrate 4, the vapor deposition source 3, and the piping part 2, the shape of the opening of the piping part 2, and the configuration in the vacuum chamber 1 are examples of the configuration of the present disclosure.

(Second Embodiment)
Next, the configuration and operation of the vapor deposition apparatus of the second embodiment will be described with reference mainly to FIG. FIG. 2 is a schematic cross-sectional view of the vapor deposition apparatus of the second embodiment. In the second embodiment, the same devices or members as those in the first embodiment are denoted by the same reference numerals.

  The configuration and operation of the vapor deposition apparatus of the second embodiment are similar to the configuration and operation of the vapor deposition apparatus of the first embodiment described above.

  However, in 2nd Embodiment, the piping part 2 is not a linear shape, and there exists a bending location. Specifically, the piping part 2 includes a lateral part 2a having a vapor deposition source 3 at one end, a bent part 2b having one end connected to the lateral part 2a and bent in an L shape, and the bent part 2b. It has the up-and-down direction part 2c connected with the end, and it forms in the L shape as a whole. Therefore, the flow of the material 8 vaporized from the vapor deposition source 3 enters the lateral part 2a of the pipe part 2 and flows in the lateral direction that is the axial direction in the lateral part 2a through the opened conductance valve 6. The bent portion 2b is bent into an L shape. Thereafter, the flow of the material 8 vaporized from the vapor deposition source 3 is guided to the vertical portion 2c and flows in the vertical direction, which is the axial direction of the vertical portion 2c, and from the opening 20 at the upper end of the vertical portion 2c. Guided to fly against a plane.

  In the second embodiment, the heating elements 91 to 96 for providing a temperature gradient as described later are configured as follows.

  The heating element 91 </ b> B is disposed on the bottom and side surfaces of the vapor deposition source 3. The heating element 92B is disposed on the outer side surface of the upstream portion of the lateral portion 2a of the piping portion 2 in which the conductance valve 6 is disposed. The heating elements 93 </ b> B are disposed on the outer side surfaces of the periphery of the transmission window 18 and the periphery of the transmission window 19 in the lateral portion 2 a of the pipe portion 2. The heating element 94B is disposed on the outer side surface of the portion from the downstream portion of the lateral portion 2a of the piping portion 2 to the bent portion 2b. The heating element 95 is disposed on the outer side surface of the upstream portion of the vertical portion 2 c from the bent portion 2 b of the pipe portion 2. The heating element 96 is disposed on the side surface outside the portion including the opening 20 on the downstream side of the vertical portion 2 c of the pipe portion 2.

  Here, the set temperatures of the heating elements 92B, 93B, and 94B having the same configuration as the heating elements 92, 93, and 94 of the first embodiment are T92B, T93B, and T94B, respectively, and the heating elements 92 to 94 of the first embodiment are used. The set temperatures of the heat generating elements 95 and 96, which are heat generating elements having the same configuration as in FIG. Then, for example, the temperature gradient of these set temperatures is set by the following equation.

T96>T94B>T95> T93B ≧ T92B ≧ T91B
According to such a configuration, when the vaporized material 8 passes through the inside of the piping part 2, in the vertical part 2 c, the temperature gradient (in which the temperature is higher in the downstream than in the upstream ( By providing T96> T95), an ascending air current is obtained. However, ascending airflow is unlikely to occur in portions other than the vertical portion 2c. Therefore, a temperature gradient in which, for example, the set temperature T94B at the bent portion 2b from the lateral portion 2a other than the vertical portion 2c is larger than the set temperature T95 at the lower portion (upstream side) of the vertical portion 2c in the pipe portion 2. By providing (T94B> T95), the easiness of flow of the vaporized material 8 in the pipe part 2 can be controlled with high accuracy, and the film thickness measurement of the deposited film can be performed with higher accuracy, so that a desired film can be obtained. Thickness film formation can be performed with higher accuracy.

  In the second embodiment, the number of the bent portions 2b is one, but various specific examples such as having an arbitrary number of bent portions are possible.

(Third embodiment)
Next, the configuration and operation of the vapor deposition apparatus of the third embodiment will be described with reference mainly to FIG. Here, FIG. 3 is a schematic cross-sectional view of the piping section 2 relating to a cross section perpendicular to the direction of flow of the vaporized material 8 of the third embodiment. In the third embodiment, the same members or apparatuses as those in the first and second embodiments are denoted by the same reference numerals.

  The configuration and operation of the vapor deposition apparatus of the third embodiment are similar to the configuration and operation of the vapor deposition apparatus of the first embodiment described above.

  However, in the third embodiment, in addition to the light 27 absorbed by the vaporized material 8, a light source 31 for irradiating light 37 that is not absorbed by the vaporized material 8 and a detection unit 32 that receives the light 37 are installed. A beam splitter 33 for mixing the light 27 and the light 37 and a beam splitter 34 for separating the light 27 and the light 37 are provided. For example, when the material 8 is trisaluminum (Alq3), the light 27 absorbed by the material 8 is light having a wavelength of 400 nm, and the light 37 not absorbed by the material 8 is light having a wavelength of 500 nm. However, the light which has the wavelength which the material 8 absorbs other than these wavelengths, and the light which has the wavelength which the material 8 does not absorb may be sufficient.

  When the piping part 2 is distorted due to heating of the piping part 2 or the like, the inclination angle of the windows 18 and 19 with respect to the light changes. Then, the path of the light 27 is changed, the incident position on the detector 12 is changed, and the measured value is changed although the density is not changed.

  Therefore, in addition to the light 27 absorbed by the vaporized material 8, the incident light 37 which is not absorbed by the vaporized material 8 can be used to detect the distortion of the windows 18 and 19 or the pipe portion 2 due to the heating of the pipe portion 2. . Although various detection methods are conceivable, for example, the variation in the detection position of the light 37 that is not absorbed by the vaporized material 8 at the detector 32 is measured, and the temperature gradient of the pipe section 2 and the light 37 detected in advance are measured. The temperature gradient of the piping part 2 is adjusted using the correlation with the detection position in the detector 32, and control is performed so that the detection position in the detector 32 is always constant. Further, when the measured value of the light 37 that is not absorbed by the vaporized material 8 changes using the light 37 that is not absorbed by the vaporized material 8 as a reference, a film thickness monitor such as a crystal resonator 28 that will be described later changes. Thus, the correlation between the measured value and the film thickness of the thin film on the substrate is reacquired and corrected, or the temperature gradient of the piping part 2 is adjusted and controlled. Here, an example in which the correlation is reacquired and corrected is as follows. For example, the correlation between the substrate film thickness and the measured value is acquired in advance. However, if it is used for a long period of time, it will be deformed due to pipe deterioration, expansion, etc., and the correlation will change. For this reason, using a film thickness monitor such as the crystal resonator 28 instead of the substrate 4 on which the film is formed, a temperature gradient that makes the correlation with the measured value linear for each set temperature is reacquired for correction. Use the reacquired temperature gradient.

  By correcting the measurement value measured with the light 27 by the above method, the film thickness can be controlled with higher accuracy.

  Of course, the optical system of the third embodiment is an example, and various specific examples are conceivable.

(Fourth embodiment)
Next, the configuration and operation of the vapor deposition apparatus according to the fourth embodiment will be described with reference mainly to FIG. FIG. 4 is a schematic cross-sectional view of the vapor deposition apparatus of the fourth embodiment. In addition, in 4th Embodiment, about the same member or apparatus as 1st-3rd embodiment, the same code | symbol is attached | subjected and illustrated.

  The configuration and operation of the vapor deposition apparatus of the fourth embodiment are similar to the configuration and operation of the vapor deposition apparatus of the first embodiment described above.

  However, in the fourth embodiment, in addition to the optical concentration measurement device 100, an optical concentration measurement device is provided in the vicinity of the opening 20 of the pipe portion 2 that is downstream of the pipe portion 2 in the flow direction of the vaporized material 8. 200 is installed. The optical density measuring apparatus 200 includes a light source 41 and a detector 42, and the light 47 emitted from the light source 41 and received by the detector 42 is analyzed by the analysis unit 13. In the piping part 2 of the optical density measuring device 200, transmission windows 45 and 46 for entering and exiting the light 47 are provided, and the transmission windows 43 and 44 are provided at the same height of the vacuum chamber 1. Is provided. Therefore, the light 47 emitted from the light source 41 passes through the transmission window 43 of the vacuum chamber 1 and enters the chamber 1, passes through the transmission window 45 of the piping unit 2, and enters the piping unit 2. The light 47 that has entered the pipe part 2 passes through the vaporized material 8 in the pipe part 2, passes through the transmission window 46 of the pipe part 2, and exits the pipe part 2, and passes through the chamber 1. The light passes through the window 44, exits from the chamber 1, and is received by the detector 42.

  In this way, by arranging the optical density measuring device 100 on the upstream side of the pipe section 2 and the optical density measuring device 200 on the downstream side, the concentration of the vaporized material 8 is measured at two locations, upstream and downstream. It is possible to measure, the setting of the temperature gradient of the piping part 2 can be controlled with higher accuracy, and stable film thickness control can be performed. Here, as an example of controlling the setting of the temperature gradient of the piping unit 2 with higher accuracy, the temperature gradient is set so that the difference between the measured values of the two optical density measuring devices 100 and 200 at the same time is the same. It is sufficient to control the setting.

  The optical density measuring device is not limited to two locations, and may be set at a plurality of three or more locations.

  Further, the optical density measuring device may be set at any different position between the vapor deposition source 3 and the substrate 4.

(Fifth embodiment)
Next, the configuration and operation of the vapor deposition apparatus of the fifth embodiment will be described with reference mainly to FIG. FIG. 5 is a schematic cross-sectional view of the vapor deposition apparatus of the fifth embodiment. In the fifth embodiment, the same members or devices as those in the first to fourth embodiments are denoted by the same reference numerals.

  The configuration and operation of the vapor deposition apparatus of the fifth embodiment are similar to the configuration and operation of the vapor deposition apparatus of the first embodiment described above.

  The difference from the first embodiment is that, in the fifth embodiment, as shown in FIG. 5, the crystal unit 28 and the shutter 29 are disposed in front of the crystal unit 28 in the vacuum chamber 1, and the shutter 29 is opened. As a result, the vaporized material 8 can be deposited on the crystal resonator 28 in the same manner as the substrate 4.

  As described above, there is a certain relationship between the film thickness of the vaporized material 8 deposited on the crystal unit 28 and the film thickness of the thin film deposited on the substrate 4. The film thickness of the thin film deposited on the crystal unit 28 is obtained indirectly from the change in the natural frequency of the crystal unit 28. Specifically, the natural frequency of the crystal unit 28 decreases according to the amount of thin film deposited on the crystal unit 28. Therefore, the thickness of the thin film deposited on the substrate 4 can be calculated by the analysis unit 13 from the measurement result of the natural frequency of the crystal resonator 28 before and after the shutter 29 is opened. That is, the crystal resonator 28 can be used as an example of a film thickness measuring device.

  As a result, the analyzer 13 can obtain the film thickness of the thin film deposited on the substrate 4 by using the crystal resonator 28 simultaneously with the optical density measuring device 100. The result measured by the crystal resonator 28 is processed by the analysis unit 13.

  Specifically, simultaneously with the measurement processing of the optical density measuring device 100, the shutter 29 of the crystal resonator 28 is opened for a predetermined time at predetermined time intervals, and the predetermined thickness is measured by the film thickness measuring device of the crystal resonator 28. The film thickness is measured over time. Next, the film thickness acquired based on the measurement value measured by the optical density measurement device 100 and the measurement value measured by the crystal resonator 28 are compared by the analysis unit 13, and the difference between the two exceeds the threshold value ( When the analysis unit 13 determines that the error range has been exceeded, the analysis unit 13 uses the measurement value measured by the crystal resonator 28 instead of the measurement value measured by the optical density measurement device 100. By doing in this way, the measured value of the optical density measuring device 100 can be corrected with the measured value of the film thickness measuring device.

  With this configuration, the shutter 29 of the crystal resonator 28 is opened only when the material in the vapor deposition source 3, the opening of the conductance valve 6, or the temperature of the piping unit 2 is changed, and the optical density measuring device 100. At the same time, by measuring the film thickness, the measured value of the optical density measuring device 100 can be corrected, and the film thickness can be controlled with higher accuracy.

  Note that the target used for film thickness measurement need not be the crystal resonator 28, but instead of the crystal resonator 28, a dummy substrate or the like that is formed under substantially the same conditions as those when the film is formed on a substrate. It may be.

  Further, the film thickness measuring device may be installed anywhere as long as the vaporized material 8 in the vacuum chamber 1 reaches.

  Moreover, an opening may be provided in a part of the vapor deposition source 3 or the piping part 2, and the film thickness may be measured using the vaporized material 8 leaking from the opening.

  By controlling the correlation between the measured concentration and the film thickness of the thin film on the substrate 4 constantly by the temperature gradient of the piping section 2 controlled as in the first to fifth embodiments described above, Film formation with a desired film thickness can be performed with high accuracy.

  The production of a maintenance-free and long-life vapor deposition apparatus makes it possible to produce a high-efficiency device with a high yield and low cost.

  In addition, it can be made to show the effect which each has by combining arbitrary embodiment or modification of the said various embodiment or modification suitably. In addition, combinations of the embodiments, combinations of the examples, or combinations of the embodiments and examples are possible, and combinations of features in different embodiments or examples are also possible.

  The vapor deposition apparatus and the vapor deposition method in the present disclosure are capable of, for example, measuring a film thickness of a vapor deposition film with higher accuracy, and performing vapor deposition on a substrate with a material vaporized in manufacturing a thin film such as an organic EL element. It is useful for use in an apparatus and a vapor deposition method.

1 Vacuum chamber (chamber)
2 Piping part 2a Lateral part 2b Bending part 2c Vertical part 3 Deposition source 4 Substrate 5 Vacuum pump (evacuation mechanism)
6 Conductance valve 7 Crucible 8 Material 91, 91B, 92, 92B, 93, 93B, 94, 94B, 95, 96 Heating element 10 Heat insulating material 11, 31, 41 Light source 12, 32, 42 Detector 13 Analyzing section 14 Conductance valve Opening control unit 15 Heating element control unit 16, 17, 18, 19, 43, 44, 45, 46 Transmission window 27, 37, 47 Light 28 Crystal resonator 29 Shutter 33, 34 Beam splitter 50 Deposition head 100, 200 Optical Concentration measuring device

Claims (13)

A vapor deposition apparatus for vaporizing a vaporized material on a surface of a substrate disposed inside a chamber,
A vapor deposition source for vaporizing the material;
Connected to the vapor deposition source, and having an opening for supplying the vaporized material from the vapor deposition source to the substrate, allows light to enter the vaporized material, pass through the vaporized material, and emit light. A piping part having a window for causing
A valve that is arranged in the pipe part and flows through the pipe part from the vapor deposition source, and adjusts the flow rate of the vaporized material;
Heating of the vapor deposition source, the valve, and the piping portion so that the piping portion has a temperature gradient such that the temperature in the portion near the opening is higher than the portion where the valve is disposed in the piping portion. And a heating control unit that controls the vapor deposition apparatus. The piping part includes a lateral part having the vapor deposition source at an end part, a bent part having one end connected to the lateral part, and a vertical part connected to the other end of the bent part. And
2. The heating control unit according to claim 1, wherein the heating control unit controls the heating so that the piping unit has a temperature gradient such that the temperature on the downstream side of the lateral direction portion is higher than the temperature on the upstream side of the vertical direction portion. The vapor deposition apparatus of description. In the pipe portion, the light is incident on the vaporized material, passes through the vaporized material, receives light emitted from the vaporized material, and optically controls the concentration of the vaporized material. Equipped with an optical density measuring device
3. The vapor deposition according to claim 1, wherein the light incident on the vaporized material is two lights of light having a wavelength that is absorbed by the vaporized material and light having a wavelength that is not absorbed by the vaporized material. apparatus.   The vapor deposition apparatus according to claim 3, wherein the optical concentration measuring device is installed at a different position between the substrate from the vapor deposition source.   The vapor deposition apparatus of Claim 4 provided with the film thickness measuring apparatus which is arrange | positioned inside the said chamber and measures the film thickness of the vapor deposition film formed in the said board | substrate.   Simultaneously with the measurement by the optical density measuring device, the film thickness measurement is performed for a predetermined time by the film thickness measuring device at predetermined time intervals, whereby the measured value of the optical density measuring device is measured by the film thickness measurement. The vapor deposition apparatus of Claim 5 which correct | amends with the measured value of an apparatus with the said optical density measurement apparatus.   The optical density measuring device measures the concentration of the vaporized material by a method selected from spectroscopic analysis, light absorption analysis, and luminescence analysis. Vapor deposition equipment.   The vapor deposition apparatus according to any one of claims 1 to 7, wherein the vapor deposition source is a crucible disposed inside the chamber and holding the vaporized material. A vapor deposition method in which vaporized material is vapor-deposited on the surface of a substrate disposed inside a chamber,
A vapor deposition source is heated to vaporize the material in the heated vapor deposition source, and a valve disposed in a portion upstream of the piping connected to the vapor deposition source. The temperature at which the temperature of the opening part at the downstream end of the pipe part becomes higher than the temperature of the upstream part of the pipe part while adjusting the flow rate of the vaporized material flowing through The piping unit is heated with a heating element so as to have a gradient, and the vaporized material is supplied from the vapor deposition source to the piping unit, and is passed through the piping unit from the opening of the piping unit to the chamber. Supply to the inside of
Light is incident on the vaporized material passing through the inside of the pipe part, light emitted from the vaporized material is received, and the concentration of the vaporized material is optically measured from the received light. Optically measured by the instrument,
Based on the measured concentration of the material, the flow rate of the vaporized material is adjusted by the valve, and the film thickness of the thin film formed by the vaporized material is acquired by the optical concentration measurement device,
Depositing the vaporized material on a surface of the substrate disposed within the chamber;
Deposition method.   The vapor deposition method of Claim 9 which changes the temperature gradient of the said piping part for every temperature of the said vapor deposition source.   In the measurement by optical density measurement by the optical density measuring device, the light having a wavelength that is not absorbed by the vaporized material simultaneously with the light having a wavelength that is absorbed by the vaporized material in the vaporized material in the pipe portion. The vapor deposition method according to claim 9 or 10, wherein the vapor deposition method is incident, and the measurement value of the optical density measurement is corrected using the intensity of light having a wavelength that does not absorb as a reference.   The optical density measuring device is installed at a different position between the deposition source and the substrate, and the pipe portion is used by using a measured value obtained by optical density measurement with the optical density measuring device at the different position. The vapor deposition method according to claim 9, wherein the temperature gradient is adjusted.   Using the film thickness measuring device arranged inside the chamber, the film thickness is measured by the film thickness measuring device simultaneously with the optical concentration measurement by the optical concentration measuring device, and the measured value obtained The vapor deposition method according to any one of claims 9 to 12, wherein a temperature gradient of the pipe portion is adjusted by using a gas.

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