JP2014152365A - Vacuum evaporation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum evaporation system capable of depositing without lowering film thickness uniformity between substrates, even when depositing continuously on a plurality of substrates for a long time.SOLUTION: A vacuum evaporation system includes a crucible for storing a vapor deposition material to be vapor-deposited on a substrate 2, and also includes an evaporation source 3 for emitting vapor of the vapor deposition material, a calculation part 7 for determining the amount of the vapor deposition material in the crucible, and a control part 8 for controlling distribution of the vapor deposition material arriving at the substrate 2 based on the amount of the vapor deposition material in the crucible.

Description

  The present invention relates to a vacuum deposition apparatus.

  In recent years, organic EL elements used for organic EL displays, organic EL lighting, and the like have attracted attention as a new industrial field. Organic EL displays are expected as next-generation displays that replace liquid crystal displays and plasma displays, and organic EL lighting is expected as next-generation lighting along with LED lighting.

  An organic EL element has a structure in which a multilayer structure in which a light emitting layer made of an organic compound, a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer are stacked is sandwiched between an electrode pair composed of an anode and a cathode. Have. By applying a voltage to the electrode, holes are injected from the anode side and electrons are injected from the cathode side into the light-emitting layer, and the organic EL element emits light by deactivation of excitons (excitons) generated by recombination. .

  The organic material used for forming the light emitting layer includes a high molecular material and a low molecular material. Among these, low molecular weight materials, which are currently mainstream, are formed by vacuum deposition to form a light emitting layer. Vacuum deposition is also used when forming other layers. In order to improve the performance of organic EL elements, doping and alloying by co-evaporation are also performed.

  An evaporation source used for vacuum deposition is installed in a vacuum chamber, and a crucible that encloses the deposition material, a heater that heats the crucible, a housing that stores the crucible and the heater, and the like are provided in the housing and ejects the deposition material. And an opening. The evaporation source is a crucible heated by a heater to evaporate or sublimate the vapor deposition material, and spray the vaporized vapor deposition material onto the substrate installed in the vacuum chamber, thereby forming the substrate and forming each layer. To do. In order to produce an organic EL element for color display, an organic EL material that emits different light is vapor deposited for each pixel in a state where the substrate and the metal mask are aligned.

  In a thin film device such as an organic EL element, since the film thickness greatly affects the characteristics of the device, the film thickness uniformity of the thin film formed on the substrate is important for improving quality and reliability. Various techniques have been developed in order to improve the uniformity of the film thickness distribution formed on the substrate. For example, technology to improve film thickness uniformity by moving / rotating the evaporation source or substrate, or technology to improve film thickness uniformity on the substrate by installing a film thickness correction plate between the evaporation source and the substrate It has been known.

  Patent Document 1 discloses a vacuum deposition apparatus that increases the degree of freedom in designing the film thickness and facilitates fine adjustment. According to claim 1 of Patent Document 1, “a vacuum film forming apparatus including a substrate holding means and a vapor deposition source in a vacuum chamber, and further, a shielding region for the vapor deposition source is provided on the film formation surface of the substrate. An in-plane film thickness of the substrate in a state in which the shielding member does not form the shielding region, comprising: at least one shielding member to be formed; a driving source for the shielding member; and a control device for the driving source. Storage means for storing in advance the measured value or calculated value of the distribution and the target value of the in-plane film thickness distribution of the substrate, and each point on the substrate based on each value input to the storage means A calculation unit that calculates a film formation time corresponding to a position (hereinafter referred to as “substrate position”) and determines an operation amount of the drive source based on the film formation time, and the drive source is based on the operation amount; To move the position of the shielding area to obtain the desired in-plane film thickness distribution. It is described as a vacuum deposition apparatus ", characterized in that configured.

JP 2007-107071 A

  When the vacuum evaporation apparatus is used for mass production of organic EL elements, it is necessary to continuously form a plurality of substrates on a long time without opening the vacuum chamber to the atmosphere. When film formation is continued for a long time, the vapor deposition material initially filled in the crucible gradually decreases. Along with this, the distribution of the vapor deposition material from the crucible to the substrate (deposition distribution of the vapor deposition material) changes, and the film thickness distribution changes between the substrates during continuous film formation of a plurality of substrates. As a result, there is a problem that the film thickness uniformity decreases between the substrates. Patent Document 1 describes a technique for increasing the degree of freedom in designing a film thickness distribution formed on a substrate, but such a problem is not considered.

  The present invention provides a vacuum evaporation apparatus that can form a film without reducing the film thickness uniformity between the substrates even if the plurality of substrates are continuously formed over a long period of time.

  A vacuum vapor deposition apparatus according to the present invention includes a crucible for storing a vapor deposition material to be vapor-deposited on a substrate, an evaporation source that discharges vapor of the vapor deposition material, a calculation unit that calculates an amount of the vapor deposition material in the crucible, And a controller that controls the distribution of the vapor deposition material reaching the substrate based on the amount of the vapor deposition material in the crucible.

  ADVANTAGE OF THE INVENTION According to this invention, even if it forms several board | substrate continuously over a long time, the vacuum evaporation apparatus which can form into a film without reducing the film thickness uniformity between board | substrates can be provided.

FIG. 2 is a schematic view schematically showing a part of the vacuum vapor deposition apparatus according to Example 1; Sectional drawing which shows the outline of the internal structure of an evaporation source before starting film-forming, and the figure which shows typically the film thickness distribution on the board | substrate corresponding to the quantity of the vapor deposition material in a crucible. Sectional drawing which shows the outline of the internal structure of an evaporation source after continuing continuous film-forming for a long time, and the figure which shows typically the film thickness distribution on the board | substrate corresponding to the quantity of the vapor deposition material in a crucible. The graph which shows the simulation result which shows the influence on the film thickness distribution of the quantity of the vapor deposition material in a crucible. FIG. 5 is a schematic view schematically showing a part of a vacuum vapor deposition apparatus according to Example 2. FIG. 5 is a schematic view schematically showing a part of a vacuum vapor deposition apparatus according to Example 3. Schematic which shows typically a part of vacuum deposition apparatus by Example 4. FIG. Schematic which shows typically a part of vacuum evaporation system by Example 5. FIG. Sectional drawing which shows the outline of the internal structure of the evaporation source of the vacuum evaporation system by Example 5, and a material supply part.

  Embodiments of a vacuum deposition apparatus according to the present invention will be described below with reference to the drawings. Below, the example which applied the vacuum evaporation system by this invention to manufacture of an organic EL element is demonstrated. The following description shows specific examples of the contents of the present invention, and the present invention is not limited only to these descriptions, but by those skilled in the art within the scope of the technical idea disclosed in this specification. Various changes and modifications are possible. The problems to be solved by the present invention and the configuration and effects of the present invention other than those described above will be clarified by the following description of embodiments.

  FIG. 1 is a schematic view schematically showing a part of the vacuum evaporation apparatus according to the first embodiment. The vacuum deposition apparatus includes a vacuum chamber 1, an evaporation source 3 having an opening, a shutter 4, a detection unit 5, a film thickness control unit 6, a calculation unit 7, a control unit 8, and a rate control unit 16. Vapor of vapor deposition material to be deposited on the substrate 2 is discharged from the opening to form a film on the substrate 2. The evaporation source 3, the shutter 4, the film thickness controller 6, and the substrate 2 are disposed in a vacuum chamber 1 that is maintained in a vacuum. In this embodiment, as an example, a film formation method for rotating the substrate 2 to improve the film thickness uniformity will be described. The substrate 2 is installed substantially horizontally in the vacuum chamber 1 and is rotated around the rotation shaft 17 by a substrate rotating unit 18 having a rotation shaft 17 in a substantially vertical direction of the substrate 2. The vertical direction is the vertical direction (the vertical direction in FIG. 1), and the horizontal direction is the direction orthogonal to the vertical direction. Details of the evaporation source 3, the shutter 4, the detection unit 5, the film thickness control unit 6, the calculation unit 7, the control unit 8, and the rate control unit 16 will be described later.

  In the geometrical arrangement of the substrate 2 and the evaporation source 3 shown in FIG. 1, the film thickness is thick at a location near the evaporation source 3 on the substrate 2 and the film thickness is thin at a location far from the evaporation source 3. Therefore, it is known that the film thickness distribution of the substrate 2 can be made uniform by rotating the substrate 2. The position of the rotating shaft 17 of the substrate 2 is not particularly limited. However, when the rotating shaft 17 passes through the approximate center of gravity of the substrate 2, the approximate rotational symmetry of the film thickness distribution with respect to the rotating shaft 17 is ensured, which is advantageous for making the film thickness distribution uniform. The substrate 2 rotates at least once during film formation.

  The film thickness control unit 6 is moved by the control unit 8 (one or both of rotational movement and parallel movement) and shields at least a part of the vapor of the vapor deposition material released from the evaporation source 3 toward the substrate 2. It is a member that controls the distribution of the vapor deposition material that reaches the substrate 2. Accordingly, the film thickness control unit 6 can improve the uniformity of the film thickness distribution formed on the substrate 2. The film thickness controller 6 is a fan-shaped plate-like member, for example, and is also referred to as a film thickness correction plate. The film thickness controller 6 rotates around a rotation axis (a rotation axis that is not parallel to the rotation axis 17) that faces in a direction intersecting the rotation axis 17 of the substrate 2. By rotating in such a direction, the distribution of the vapor deposition material reaching the substrate 2 can be effectively controlled.

  The shutter 4 can control the release of vapor of the vapor deposition material from the opening of the evaporation source 3 toward the substrate 2 by the opening / closing operation thereof. When the shutter 4 is closed, all of the imaginary straight lines from the opening of the evaporation source 3 to each point on the substrate 2 intersect with the shutter 4, and vapor of the vapor deposition material flowing from the opening of the evaporation source 3 to the substrate 2 is generated. The substrate 2 is not deposited by being blocked by the shutter 4. When the shutter 4 is opened, the imaginary straight line from the opening of the evaporation source 3 to each point on the substrate 2 does not intersect the shutter 4, and the vapor of the vapor deposition material reaches the substrate 2 from the opening of the evaporation source 3. The substrate 2 is deposited. By opening and closing the shutter 4, the film formation time can be controlled for each substrate, and a desired film thickness can be obtained.

  FIG. 1 shows an example in which one shutter 4 is directly attached to the evaporation source 3. The present invention is not limited to this aspect, and a plurality of shutters 4 may be attached to the evaporation source 3. Further, the shutter 4 may be provided separately from the evaporation source 3 without being attached directly to the evaporation source 3.

  The detection unit 5 is a general rate sensor that detects a deposition rate, and monitors the deposition rate. The deposition rate is also referred to as a deposition rate or a film formation rate, and represents a film formation rate. For the detection unit 5, for example, a film thickness sensor can be used. In the detection unit 5, the virtual straight line from the opening of the evaporation source 3 to the detection unit 5 and the shutter 4 do not intersect so that the vapor from the evaporation source 3 to the detection unit 5 is not blocked by the shutter 4. It is necessary to arrange in such a position. The vapor deposition rate detected by the detection unit 5 is transmitted to the rate control unit 16.

  The rate control unit 16 feedback-controls the input power to the heater included in the evaporation source 3 so that the vapor deposition rate detected by the detection unit 5 becomes a predetermined numerical value or a numerical range. As will be described later, the evaporation source 3 heats the vapor deposition material with a heater and vaporizes the vaporized material on the substrate 2. Therefore, the evaporation source 3 can be controlled by the rate control unit 16 to change the amount of vapor released (vapor deposition rate). The vacuum vapor deposition apparatus can perform stable rate control such that the vapor deposition rate is constant by the detection unit 5 and the rate control unit 16. In order to make the film thickness on the substrate 2 uniform, stable rate control is necessary.

  Note that the angle from the opening of the evaporation source 3 to the detection unit 5 with respect to the vertical direction is preferably substantially equal to the angle θ from the opening of the evaporation source 3 to the rotation center of the substrate 2. The rotation axis 17 of the substrate 2 is a fixed point of rotation, and even when the substrate 2 rotates, substantially the same amount of vapor deposition material is always deposited and is not affected by the distribution control of the vapor deposition material by the film thickness controller 6. For this reason, when these angles are made substantially equal, the deposition rate at the rotation center of the substrate 2 can be kept substantially constant by controlling the rate so that the detection value of the detection unit 5 is kept substantially constant.

  Next, an outline of a film forming process in the vacuum evaporation apparatus according to the present embodiment will be described. First, the single substrate 2 is transferred into the vacuum chamber 1, aligned with the mask, attached to the substrate holder, and rotated around the rotation shaft 17. The shutter 4 is opened to start vapor deposition, and a film is formed on the substrate 2 for a predetermined time. When film formation is completed, the shutter 4 is closed and then the rotation of the substrate 2 is stopped. Thereafter, the substrate 2 is removed from the substrate holder and carried out of the vacuum chamber 1. By repeating the above steps, film formation is continuously performed on the plurality of substrates 2. After continuous film formation, the vacuum chamber 1 is opened to the atmosphere and maintenance is performed. The maintenance is performed as necessary, such as replenishment of the vapor deposition material 10 and removal of the vapor deposition material 10 attached to the shutter 4 and the film thickness controller 6.

  2A and 2B are a cross-sectional view showing an outline of the internal structure of the evaporation source 3 and a diagram schematically showing a film thickness distribution on the substrate 2 corresponding to the amount of the vapor deposition material 10 in the crucible 9. 2A and 2B, the lower diagram is a cross-sectional view showing an outline of the internal structure of the evaporation source 3, and the upper diagram schematically shows the film thickness distribution on the substrate 2 corresponding to the amount of the vapor deposition material 10 in the crucible 9. FIG.

  2A and 2B, the evaporation source 3 includes a crucible 9 for storing a vapor deposition material 10 to be deposited on the substrate 2, a heater 11 for heating the crucible 9, and a housing 12 for storing these. FIG. 2A shows the state (state A) of the evaporation source 3 before starting film formation. FIG. 2B shows a state (state B) of the evaporation source 3 after continuous film formation for a long time, and the amount of the vapor deposition material 10 stored in the crucible 9 is smaller than that in the state of FIG. 2A. ing.

  2A and 2B, the vertical axis schematically shows the film thickness on the substrate 2, and the horizontal position in the substrate 2 (horizontal axis) is the position of the crucible 9 shown at the bottom. It corresponds. The film thickness distribution in the state B shown in FIG. 2B is intensively thicker at a position near the center of the opening of the crucible 9 than the film thickness distribution in the state A shown in FIG. 2A.

  As the vapor deposition material 10, an organic material, an inorganic material, a metal material, or the like is used, and the vapor deposition material 10 is classified into a sublimation system and a melting system depending on whether the vapor deposition temperature is lower than the melting point or higher than the melting point. The crucible 9 is heated by radiant heat from the heater 11 heated by resistance to heat the vapor deposition material 10. The heated vapor deposition material 10 is vaporized by sublimation or evaporation. The evaporation source 3 (including the crucible 9) has an opening, and discharges the vaporized deposition material 10 (vapor of the deposition material 10) from the opening toward the substrate 2. The housing 12 is cooled by cooling water or the like.

  When continuous film formation is continued for a long time, the amount of the vapor deposition material 10 in the crucible 9 gradually decreases and changes from the state A in FIG. 2A to the state B in FIG. 2B. The distribution (deposition distribution of the vapor deposition material 10) when the vapor deposition material 10 is released from the opening of the crucible 9 toward the substrate 2 is the position of the evaporation surface (or sublimation surface) of the vapor deposition material 10 in the crucible 9. It depends on the amount of the vapor deposition material 10 because it is affected by the influence, that is, the distance from the evaporation surface (or sublimation surface) of the vapor deposition material 10 to the opening of the crucible 9.

  When the amount of the vapor deposition material 10 in the crucible 9 decreases and changes from the state A in FIG. 2A to the state B in FIG. 2B, the position of the evaporation surface (or sublimation surface) of the vapor deposition material 10 decreases, and the evaporation surface of the vapor deposition material 10 The distance from the (or sublimation surface) to the opening of the crucible 9 is increased. As a result, the directivity of vapor released from the evaporation surface (or sublimation surface) to the substrate 2 is increased. That is, the emission distribution of the vapor deposition material 10 is such that when the amount of the vapor deposition material 10 in the crucible 9 decreases, the vapor of the vapor deposition material 10 concentrates at a position near the center of the opening of the crucible 9. Since the emission distribution of the vapor deposition material 10 is highly correlated with the film thickness distribution on the substrate 2, the film thickness distribution on the substrate 2 when the amount of the vapor deposition material 10 is reduced is as shown in the upper part of FIG. The position near the center of the opening of the crucible 9 is intensively thick, which is different from the film thickness distribution (film thickness distribution spread on the substrate 2) when the amount of the vapor deposition material 10 shown in the upper part of FIG. 2A is large. .

  Therefore, in the conventional vacuum vapor deposition apparatus, as the amount of the vapor deposition material 10 during the continuous film formation decreases, the emission distribution of the vapor deposition material 10 changes and the film thickness distribution formed on the substrate 2 has a plurality of substrates. There is a problem that the film thickness uniformity is lowered and the film thickness uniformity is lowered.

  FIG. 3 is a graph showing a simulation result showing the influence of the amount of the vapor deposition material 10 in the crucible 9 on the film thickness distribution. The graph of FIG. 3 shows the calculation result when the film thickness distribution formed on the substrate 2 is obtained for each of the states A and B shown in FIGS. 2A and 2B. The height difference between the nozzle and the substrate was 740 mm, and the horizontal distance between the center of the substrate 2 (position of the rotation axis 17 of the substrate) and the center of the opening of the evaporation source 3 was 530 mm.

  As shown in the graph of FIG. 3, in both the state A and the state B, the film thickness is thick at a place near the evaporation source 3 and the film thickness is thin at a place far from the evaporation source 3. However, the film thickness uniformity in the substrate 2 is 3.64% in the state A and 7.56% in the state B. Thus, with the change in the amount of the vapor deposition material 10 in the crucible 9, the vapor release distribution of the vapor deposition material 10 changes, and the film thickness distribution formed on the substrate 2 also changes. As a result, when continuous film formation is performed, the film thickness distribution changes with a change in the amount of the vapor deposition material 10 in the crucible 9 between a plurality of substrates, and the film thickness uniformity decreases.

  In this embodiment, the movement (one or both of the rotational movement and the parallel movement) of the film thickness control unit 6 is controlled based on the amount of the vapor deposition material 10 in the crucible 9, and a plurality of substrates generated during continuous film formation are controlled. Reduce the change in film thickness distribution at.

  First, the amount of the vapor deposition material 10 in the crucible 9 is calculated using the detection unit 5 and the calculation unit 7. An example of the calculation method will be described below.

  The detector 5 observes the vapor released spatially from the crucible 9 from a specific direction and detects the deposition rate. Here, since the purpose is to calculate an approximate value of the amount of the vapor deposition material 10 in the crucible 9, the flow rate of the vapor deposition material (unit: kg / second, for example) is considered to be approximately proportional to the detected value of the vapor deposition rate by the detection unit 5. It is done. This proportionality factor can be determined in advance by experiment or calculation. Therefore, it is possible to estimate the flow rate of the vapor deposition material 10 from the detected value of the vapor deposition rate by the detection unit 5.

  The calculation unit 7 obtains the flow rate of the vapor deposition material 10 from the vapor deposition rate detected by the detection unit 5, and obtains the decrease amount of the vapor deposition material 10 and the amount of the vapor deposition material 10 in the crucible 9. The decrease amount of the vapor deposition material 10 can be obtained by integrating the flow rate over time. The time integration may be performed continuously or discontinuously. The amount of the vapor deposition material 10 in the crucible 9 can be calculated by subtracting the reduction amount of the vapor deposition material 10 from the initial value of the amount of the vapor deposition material 10 in the crucible 9. The amount of the vapor deposition material 10 may be obtained either by the weight of the vapor deposition material 10 or by the volume. If the volume density is known, the weight and volume can be converted. The calculation unit 7 also calculates the height of the evaporation surface of the vapor deposition material 10 (the height of the vapor deposition material 10 in the crucible 2) from the amount of the vapor deposition material 10 by using information on the internal shape of the crucible 2. Is possible.

  Next, the control unit 8 controls the film thickness control unit 6 based on the amount of the vapor deposition material 10 in the crucible 9 obtained by the calculation unit 7 and the control information of the film thickness control unit 6. The control information of the film thickness control unit 6 includes information about the correspondence between the amount of the vapor deposition material 10 in the crucible 9 and the movement amount (movement distance and rotation angle) of the film thickness control unit 6. Therefore, the control unit 8 moves the film thickness control unit 6 according to the amount of the vapor deposition material 10 in the crucible 9 to control the distribution of the vapor deposition material reaching the substrate 2.

  The calculation part 7 and the control part 8 are comprised from PC, a microcomputer, etc. which have a memory | storage part and a calculation part, for example. The storage unit of the calculation unit 7 stores the proportionality coefficient used to obtain the flow rate of the vapor deposition material 10 from the vapor deposition rate detected by the detection unit 5, the initial value of the amount of the vapor deposition material 10 in the crucible 9, and the internal shape of the crucible 2. Information such as information required by the calculation unit 7 is held. The storage unit of the control unit 8 holds information required by the control unit 8 such as control information of the film thickness control unit 6. The storage unit of the calculation unit 7 can also hold information about the amount of the vapor deposition material 10 in the crucible 9 and the release distribution of the vapor deposition material 10 corresponding thereto. These pieces of information can be acquired or set in advance through experiments or calculations, and can be stored in advance in the calculation unit 7 or the control unit 8. For example, the information about the amount of the vapor deposition material 10 in the crucible 9 and the release distribution of the vapor deposition material 10 corresponding to the amount can be obtained in advance from experiments and calculations, and the control information of the film thickness control unit 6 is It can be set in advance. The storage unit of the calculation unit 7 further holds the obtained information such as the amount of the vapor deposition material 10 in the crucible 9.

  Therefore, even if the amount of the vapor deposition material 10 in the crucible 9 changes, the control unit 8 mechanically moves the film thickness control unit 6 according to the amount of the vapor deposition material 10 and the control information of the film thickness control unit 6 to continuously It is possible to reduce a change in film thickness distribution among the plurality of substrates 2 that occurs during film formation. For example, when the amount of the vapor deposition material 10 is smaller than a predetermined amount, the vapor of the vapor deposition material 10 is further concentrated at a position near the center of the opening of the evaporation source 3, so that the film thickness control unit 6 is moved. Thus, a part or all of the vapor of the vapor deposition material 10 from the evaporation source 3 toward the portion of the substrate 2 near the center of the opening of the evaporation source 3 is shielded. In this way, the amount of the vapor deposition material 10 deposited on the portion of the substrate 2 close to the center of the opening of the evaporation source 3 can be reduced, and the change in the film thickness distribution among the plurality of substrates 2 can be reduced. .

  As can be seen from the simulation result shown in FIG. 3, the film thickness on the substrate 2 is thicker immediately above the evaporation source 3 than in the vicinity of the rotating shaft 17. Therefore, the thickness of the substrate 2 is thicker at the end than the center of rotation. Therefore, when the film thickness distribution on the substrate 2 is as shown in FIG. 3, the film thickness control unit 6 is a plate-like member, and connects the center of the opening of the evaporation source 3 and the rotation center of the substrate 2. A shape whose area increases as the distance from the virtual straight line increases is preferable (see FIG. 1). For example, the film thickness control unit 6 is formed in a fan shape, and the area increases in proportion or more as the distance from the virtual straight line connecting the center of the opening of the evaporation source 3 and the rotation center of the substrate 2 increases. By adopting the shape, the uniformity of the film thickness distribution on the plurality of substrates 2 can be further improved.

  The timing at which the control unit 8 moves the film thickness control unit 6 is not particularly limited. For example, it may be performed periodically each time a film is formed on a plurality of predetermined substrates 2. The installation position of the film thickness control unit 6 is not particularly limited, but should not intersect with an imaginary straight line from the opening of the evaporation source 3 toward the rotation center of the substrate 2. This is because the center of rotation of the substrate 2 is not always deposited by the film thickness controller 6 when the film thickness controller 6 and the virtual straight line intersect. The shape of the film thickness controller 6 is controlled by the controller 8 and can change the amount of vapor of the vapor deposition material 10 deposited on the substrate 2 in accordance with the change in the amount of the vapor deposition material 10 in the crucible 9. If there is, it will not be specifically limited.

  In the present embodiment, an example in which the calculation unit 7 and the control unit 8 are separated has been described, but these may be integrated. The calculation method of the quantity of the vapor deposition material 10 in the crucible 9 is not limited to said example, A number of methods are possible.

  As described above, in this embodiment, the amount of the vapor deposition material 10 in the crucible 9 is calculated based on the vapor deposition rate detected by the detection unit 5, and the film thickness control unit 6 is controlled based on the amount of the vapor deposition material 10. Then, the film thickness distribution on the substrate 2 is controlled by changing the distribution of the vapor deposition material 10 deposited on the substrate 2. Thus, in the vacuum vapor deposition apparatus according to the present embodiment, by controlling the film thickness distribution on the substrate 2 based on the amount of the vapor deposition material 10 in the crucible 9, a plurality of continuous film depositions for a long time are performed. It is possible to form a film stably without reducing the film thickness uniformity between the substrates 2.

  FIG. 4 is a schematic view schematically showing a part of the vacuum evaporation apparatus according to the second embodiment. 4, the same reference numerals as those in FIG. 1 denote the same or common elements as those in FIG. 1, and the description of these elements will be omitted.

  The vacuum vapor deposition apparatus according to the present embodiment is the same as the vacuum vapor deposition apparatus described in the first embodiment, except that the weight measuring unit 14 that measures the weight of the crucible 9 or the evaporation source 3 and the amount of the vapor deposition material 10 in the crucible 9 are calculated. The weight measurement unit 14 sends the measurement value to the calculation unit 7, and the calculation unit 7 calculates the amount of the vapor deposition material 10 in the crucible 9 based on the measurement value.

  For the weight measuring unit 14, for example, a weight scale can be used. The weight measuring unit 14 and the calculating unit 7 may be integrated. When the vacuum deposition apparatus has a plurality of crucibles 9 or a plurality of evaporation sources 3, one weight measuring unit 14 may measure the weight of the plurality of crucibles 9 or the plurality of evaporation sources 3, or the weight measuring unit. A plurality of 14 may be provided, and one weight measuring unit 14 may measure the weight of one crucible 9 or the evaporation source 3.

  The calculation unit 7 uses the information from the detection unit 5 in the first embodiment, but calculates the amount of the vapor deposition material 10 in the crucible 9 using the information from the weight measurement unit 14 in the present embodiment. . That is, the calculation unit 7 sets the decrease in the weight of the crucible 9 or the evaporation source 3 measured by the weight measurement unit 14 as the decrease in the vapor deposition material 10, and calculates the vapor deposition material 10 from the initial value of the amount of the vapor deposition material 10 in the crucible 9. The amount of the vapor deposition material 10 in the crucible 9 is calculated by subtracting the decrease amount.

  Other configurations are the same as those in the first embodiment. Based on the amount of the vapor deposition material 10 in the crucible 9, the film thickness controller 6 changes the amount of vapor of the vapor deposition material 10 deposited on the substrate 2 to change the substrate 2. The film thickness distribution is controlled. Similarly to the first embodiment, the present embodiment also requires rate control so that the deposition rate is constant, and for this purpose, the detector 5 such as a film thickness sensor and the rate controller 16 are provided.

  In the present embodiment, the weight of the crucible 9 or the evaporation source 3 can be measured in real time, and the measured value does not depend on the past measurement history. Therefore, compared with Example 1, the amount of the vapor deposition material 10 in the crucible 9 can be directly calculated, and a more reliable value can be obtained.

  Thus, in the vacuum vapor deposition apparatus according to the present embodiment, the amount of the vapor deposition material 10 in the crucible 9 can be calculated more accurately by using the measurement value of the weight measurement unit 14, and the film thickness on the substrate 2. The distribution can be controlled with higher accuracy. Therefore, the effect of preventing the film thickness uniformity among the plurality of substrates 2 from being deteriorated with respect to continuous film formation for a long time is even greater.

  FIG. 5 is a schematic view schematically illustrating a part of the vacuum evaporation apparatus according to the second embodiment. 5, the same reference numerals as those in FIG. 1 denote the same or common elements as those in FIG. 1, and the description of these elements is omitted.

  The vacuum vapor deposition apparatus according to the present embodiment is the vacuum vapor deposition apparatus described in the first embodiment, and includes at least a plurality of evaporation sources 3 and an exchange unit 13 on which these evaporation sources 3 are placed and moved. The exchange unit 13 is, for example, a disk-shaped rotary table on which a plurality of evaporation sources 3 can be placed, and the position of each evaporation source 3 can be moved by rotating. In this embodiment, a case where there are two evaporation sources 3 will be described. The evaporation source 3 may be a plurality of three or more.

  In the plurality of evaporation sources 3 used in the present embodiment, when the amount of the evaporation material 10 in the crucible 9 decreases, the position of each evaporation source 3 is moved by the exchanging unit 13 and the evaporation sources 3 used for evaporation can be replaced. Is possible. Therefore, the time during which continuous film formation can be performed without opening the vacuum chamber 1 to the atmosphere can be extended. In the evaporation source 3 used for vapor deposition, the release of vapor of the vapor deposition material toward the substrate 2 is controlled by the opening / closing operation of the shutter 4.

  In the present embodiment, the calculation unit 7 holds an initial value of the amount of the vapor deposition material 10 stored in each evaporation source 3 in the storage unit of the calculation unit 7 in advance, and the evaporation source 3 used for vapor deposition. The amount of the vapor deposition material 10 in the crucible 9 is obtained. In addition, when replacing the evaporation source 3 by the exchanging unit 13, the calculating unit 7 holds the information on the amount of the evaporation material 10 of the evaporation source 3 before the exchange that is held, and the evaporation material of the evaporation source 3 after the exchange. Update to 10 quantities of information. Thus, by linking the exchanging unit 13 and the calculating unit 7, the same effect as that of the vacuum vapor deposition apparatus of the first embodiment can be obtained even in the vacuum vapor deposition apparatus of the present example including the plurality of evaporation sources 3.

  In the present embodiment, an example of a vacuum deposition apparatus including the exchange unit 13 that moves the plurality of evaporation sources 3 by rotation is described. However, the exchange unit 13 moves the positions of the plurality of evaporation sources 3 by rotation. It is not limited to only. For example, it is also possible to use an exchange unit 13 in which a plurality of evaporation sources 3 are arranged on a straight line and the evaporation source 3 is moved in this linear direction.

  Similarly to the first embodiment, the present embodiment also requires rate control so that the deposition rate is constant, and for this purpose, the detector 5 such as a film thickness sensor and the rate controller 16 are provided. The vacuum vapor deposition apparatus of the present embodiment may include only one detection unit 5 or the same number as the number of evaporation sources 3. When only one detection unit 5 is provided, one detection unit 5 is used for a plurality of evaporation sources 3. When the same number of detection units 5 as the number of evaporation sources 3 are provided, the detection units 5 are switched for use with the respective evaporation sources 3.

  FIG. 6 is a schematic view schematically illustrating a part of the vacuum evaporation apparatus according to the fourth embodiment. 6, the same reference numerals as those in FIG. 1 denote the same or common elements as those in FIG. 1, and the description of these elements will be omitted.

  The vacuum vapor deposition apparatus according to the present embodiment includes a plurality of detection units 5 provided at different locations in the vacuum vapor deposition apparatus described in the first and second embodiments, and the calculation unit 7 includes a plurality of detection units 5. Based on the above information, the amount of the vapor deposition material 10 in the crucible 9 is calculated. FIG. 6 shows an example in which the vacuum vapor deposition apparatus according to the first embodiment includes two detection units 5 as an example.

  The calculation part 7 calculates | requires the flow volume of the vapor deposition material 10 using the several vapor deposition rate which the several detection part 5 detected in the mutually different place. When the obtained flow rate is integrated by the film formation time, the reduction amount of the vapor deposition material 10 can be calculated.

  An example of a method for obtaining the flow rate of the vapor deposition material 10 from a plurality of vapor deposition rates will be described. The vapor release distribution of the vapor deposition material 10 exiting from the opening of the crucible 9 can be practically expressed by an approximate expression using a power (cos θ) ^ N of a cosine function. Since the flow rate is obtained by integrating the vapor discharge distribution with the solid angle θ, the coefficient of the expression representing the discharge distribution is normalized by this integration. From a plurality of vapor deposition rates detected using a plurality of detectors 5, the exponent N and the flow rate in the equation representing the vapor release distribution can be obtained.

  The vacuum vapor deposition apparatus according to the present embodiment includes a plurality of detection mechanisms 5 and obtains the flow rate of the vapor deposition material 10 from the vapor deposition rates measured at a plurality of locations. It is not necessary to use a proportional coefficient between the vapor deposition rate and the flow rate determined by calculation, and the flow rate of the vapor deposition material 10 can be obtained with higher accuracy.

  Therefore, in this embodiment, the amount of the vapor deposition material 10 in the crucible 9 can be calculated more accurately, and the film thickness distribution on the substrate 2 can be controlled more accurately. Therefore, the effect of not reducing the film thickness uniformity among the plurality of substrates 2 with respect to continuous film formation for a long time is even greater.

  FIG. 7 is a schematic view schematically illustrating a part of the vacuum evaporation apparatus according to the fifth embodiment. 7, the same reference numerals as those in FIG. 1 denote the same or common elements as those in FIG. 1, and the description of these elements will be omitted.

  The vacuum vapor deposition apparatus according to the present embodiment is the vacuum vapor deposition apparatus described in the first embodiment, and includes at least a material supply unit 15 that supplies the vapor deposition material 10 to the crucible 9 of the evaporation source 3, and the film thickness control unit 6 does not necessarily include. There is no need. The material supply unit 15 is controlled by the control unit 8 and supplies the vapor deposition material 10 to the crucible 9. The material supply unit 15 is not particularly limited as long as it can be controlled by the control unit 8 and can supply the vapor deposition material 10 to the crucible 9. For example, a hopper having an on-off valve may be used, and the deposition material 10 may be supplied to the crucible 9 when the on-off valve is opened under the control of the control unit 8.

  FIG. 8 is a cross-sectional view showing an outline of the internal structure of the evaporation source 3 and the material supply unit 15 of the vacuum evaporation apparatus according to the fifth embodiment. 8, the same reference numerals as those in FIG. 2A indicate the same or common elements as those in FIG. 2A, and the description of these elements is omitted.

  As described in Example 1, when continuous film formation is continued for a long time, the amount of the vapor deposition material 10 in the crucible 9 gradually decreases as shown in FIGS. 2A and 2B. Along with this, since the position of the evaporation surface (or sublimation surface) of the vapor deposition material 10 changes, the emission distribution of the vapor deposition material 10 also changes. As a result, the film thickness distribution changes between the plurality of substrates 2 during continuous film formation.

  The vacuum vapor deposition apparatus according to this embodiment has a material supply unit 15 and supplies the vapor deposition material 10 to the crucible 9 as described below. The calculation part 7 calculates | requires the quantity of the vapor deposition material 10 in the crucible 9 by any of the methods described in Example 1 to Example 4, for example. The control unit 8 controls the material supply unit 15 each time the amount of the vapor deposition material 10 in the crucible 9 decreases by a predetermined amount compared to the initial value. The material supply unit 15 is controlled by the control unit 8 to supply the reduced amount of the vapor deposition material 10 into the crucible 9, and the amount of the vapor deposition material 10 in the crucible 9 is set to the same amount as or the same amount as the initial value. Increase to.

  In this case, since the amount of the vapor deposition material 10 in the crucible 9 is decreased, the discharge distribution of the vapor deposition material 10 that is concentrated at a position close to the center of the opening of the crucible 9 is distributed over the entire opening. The distribution of the vapor deposition material 10 can be controlled. The calculation unit 7 holds the above-described predetermined amount in the storage unit of the calculation unit 7 in advance.

  The vacuum vapor deposition apparatus of the present embodiment includes a material supply unit 15, and the control unit 8 controls the material supply unit 15 based on the amount of the vapor deposition material 10 in the crucible 9 to supply the vapor deposition material 10 to the crucible 9. Thus, the decrease in the amount of the vapor deposition material 10 in the crucible 9 can be kept within the range of the predetermined amount described above. Since the crucible 9 can always hold the vapor deposition material 10 in an amount within a certain range (a value between the initial value and the value obtained by subtracting the above-mentioned predetermined amount from the initial value), the vacuum of the present embodiment. In the vapor deposition apparatus, a change in the distribution of the vapor deposition material 10 that reaches the substrate 2 can be suppressed. For this reason, compared with the vacuum vapor deposition apparatus of Example 1 to Example 4, there exists an advantage that members, such as the film thickness control part 6 which controls distribution of the vapor deposition material 10 which reaches | attains the board | substrate 2, are not necessarily required.

  As described above, the vacuum vapor deposition apparatus according to the present embodiment includes the material supply unit 15 that supplies the vapor deposition material 10 to the crucible 9 and is obtained by any one of the methods described in the first to fourth embodiments. Since the control unit 8 controls the material supply unit 15 based on the amount of the vapor deposition material 10 in 9, the crucible 9 can always hold an amount of the vapor deposition material 10 within a certain range. It is possible to reduce the change in the film thickness distribution on the substrate 2 occurring therein. As described above, the vacuum deposition apparatus according to the present embodiment can stably form a film without deteriorating the film thickness uniformity between the plurality of substrates 2 for a long-time continuous film formation.

  In addition, this invention is not limited to said Example, Various modifications are included. For example, the above-described embodiments are described in detail for easy understanding of the present invention, and the present invention is not necessarily limited to an aspect including all the configurations described.

  Each configuration of the control device according to the present invention may be realized by hardware, for example, by designing a part or all of them with an integrated circuit. Some or all of these may be realized by software so that the processor interprets and executes a program that realizes each function. Information such as programs, tables, files, measurement information, and calculation information for realizing each function is stored in a recording device such as a memory, a hard disk, and an SSD (Solid State Drive), or an IC card, an SD card, and a DVD. It can be recorded on a recording medium. Therefore, each function of the control device according to the present invention can be realized as a processing unit, a processing unit, a program module, and the like.

  Further, in each drawing, control lines and information lines are described as necessary for explanation, and not all control lines and information lines necessary as products are necessarily described. In an actual product, it may be considered that almost all components are connected to each other.

  DESCRIPTION OF SYMBOLS 1 ... Vacuum chamber, 2 ... Board | substrate, 3 ... Evaporation source, 4 ... Shutter, 5 ... Detection part, 6 ... Film thickness control part, 7 ... Calculation part, 8 ... Control part 8, 9 ... Crucible, 10 ... Evaporation material, DESCRIPTION OF SYMBOLS 11 ... Heater, 12 ... Housing, 13 ... Exchange part, 14 ... Weight measuring part, 15 ... Material supply part, 16 ... Rate control part, 17 ... Substrate rotation axis, 18 ... Substrate rotation part.

Claims (7)

Comprising a crucible for storing a vapor deposition material to be vapor-deposited on a substrate, and an evaporation source for releasing the vapor of the vapor deposition material;
A calculation unit for obtaining the amount of the vapor deposition material in the crucible;
Based on the amount of the vapor deposition material in the crucible, a control unit that controls the distribution of the vapor deposition material reaching the substrate;
A vacuum vapor deposition apparatus comprising: A plate-like member for shielding vapor of the vapor deposition material released from the evaporation source to the substrate;
A detector that detects a vapor deposition rate of the vapor of the vapor deposition material, and
The calculation unit obtains the amount of the vapor deposition material in the crucible based on the vapor deposition rate,
The vacuum deposition apparatus according to claim 1, wherein the control unit controls the distribution of the deposition material that reaches the substrate by moving the plate-like member based on the amount of the deposition material in the crucible. A plurality of the detection units;
The vacuum deposition apparatus according to claim 2, wherein the calculation unit obtains the amount of the deposition material in the crucible based on the plurality of deposition rates detected by the plurality of detection units. Comprising a plurality of said evaporation sources;
A plurality of the evaporation sources are placed, and an exchange unit that replaces the evaporation sources used for vapor deposition by moving the positions of these evaporation sources is further provided,
The calculation unit obtains the amount of the vapor deposition material in the crucible of the evaporation source used for vapor deposition, and holds the vapor deposition of the evaporation source before being held when replacing the evaporation source by the exchange unit. The vacuum evaporation system according to claim 1, wherein the information on the amount of material is updated to information on the amount of the evaporation material of the evaporation source after replacement. A material supply unit for supplying the vapor deposition material to the crucible;
A detector that detects a vapor deposition rate of the vapor of the vapor deposition material, and
The calculation unit obtains the amount of the vapor deposition material in the crucible based on the vapor deposition rate,
The control unit controls the distribution of the vapor deposition material reaching the substrate by controlling the material supply unit based on the amount of the vapor deposition material in the crucible and supplying the vapor deposition material to the crucible. The vacuum evaporation apparatus according to claim 1. A plate-like member for shielding vapor of the vapor deposition material released from the evaporation source to the substrate;
A weight measuring unit for measuring at least the weight of the crucible,
The calculation unit obtains the amount of the vapor deposition material in the crucible based on the weight of the crucible,
The vacuum deposition apparatus according to claim 1, wherein the control unit controls the distribution of the deposition material that reaches the substrate by moving the plate-like member based on the amount of the deposition material in the crucible. A substrate rotation unit that rotates the substrate around an axis perpendicular to the substrate;
The vacuum deposition apparatus according to claim 2, wherein the control unit rotates and moves the plate member around an axis in a direction intersecting the axis.

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