KR20200115029A - Film formation apparatus and film formation method - Google Patents

Abstract

Provided is a film formation apparatus capable of realizing both a uniform film thickness distribution and an improved material yield. An evaporation source container, in a chamber, accommodating a film formation material, disposed below a film formation target, and having an ejection port open upward, performs a reciprocating movement by moving from a separate position away from a rotating axis to a proximity position adjacent to the rotating axis and returning to the separate position in the direction perpendicular to the rotating axis of the film formation target. A crystal oscillator, which is provided in a film formation monitor obtaining a film formation rate of the film formation material evaporated from the evaporation source container with respect to the film formation target, moves in the chamber so that an opposite state to the evaporation source container, which performs the reciprocating movement, is maintained.

Description

A film forming apparatus and a film forming method TECHNICAL FIELD [FILM FORMATION APPARATUS AND FILM FORMATION METHOD}

The present invention relates to a film forming apparatus and a film forming method for forming a thin film on a film-forming object by a vacuum evaporation method.

A film forming apparatus that forms a thin film on a substrate as a film-forming object. A container (crucible) containing a film-forming material is heated in a vacuum chamber, and the film-forming material is evaporated (sublimated or evaporated) to be sprayed out of the container. There is a film forming apparatus of a vacuum evaporation method that adheres and deposits on. In the configuration of forming a film using a crucible with an upwardly open injection port of the film-forming material as an evaporation source for a rotating substrate with the film-forming surface facing downward, the film thickness distribution varies depending on the arrangement of the evaporation source with respect to the substrate. do. The amount of deposition per unit time of the film-forming material (film-forming rate) on the horizontal plane arranged above the evaporation source peaks just above the injection port, and decreases while gradually smoothing the gradient radially outward from the center of the peak. To form.

In the conventional device design, the uniformity of the film thickness distribution is emphasized, and the structure in which the evaporation source is arranged so that the film-forming surface of the substrate is off the position immediately above the evaporation source (ejection port) has been mainstream. That is, it is an arrangement configuration in which film formation is performed in a region where the gradient of the change in the film formation rate is gentle in the above-described mountain-shaped film thickness distribution. However, since most of the film-forming material discharged directly upward from the injection port is not used for film-forming and becomes useless, an arrangement structure with poor material yield results.

In recent years, a vapor deposition material of a high-performance material (ie, high cost) has been used, and the material yield is important. In other words, there is a tendency to adopt a configuration in which the evaporation source is disposed immediately below the substrate (in a position where the evaporation source overlaps (includes) the substrate when projected in the vertical direction). However, in the vicinity of the crucible where the film formation rate peaks, the gradient of the change in the film formation rate is steep (the change in the amount of adhesion per unit time with respect to the distance from the center of the peak is large). It becomes a difficult area to form. That is, the film thickness distribution tends to deteriorate, and there is always a risk of deteriorating production quality.

In Patent Documents 1 and 2, an apparatus configuration for achieving uniform film thickness by changing the position of the evaporation source disposed immediately below the substrate is described. However, in the apparatus described in Patent Document 1, since the relative position of the evaporation source changes with respect to the film formation rate monitor (crystal vibrator) fixed in the chamber, the monitor condition is reset every time the evaporation source is moved. In addition, the apparatus described in Patent Document 2 is not described with respect to the film formation rate monitor, and is not configured in consideration of the film formation rate monitor environment.

Patent Document 1: Japanese Patent Laid-Open No. 2007-224354 Patent Document 2: Japanese Patent Laid-Open Publication No. 2004-307880

An object of the present invention is to provide a film forming apparatus capable of achieving both uniform film thickness distribution and improvement in material yield.

In order to achieve the above object, the film forming apparatus of the present invention,

Chamber,

A rotation support portion rotatably supporting a film-forming object about a rotation axis perpendicular to the film-forming surface in the chamber, with the film-forming surface facing downward;

An evaporation source container containing a film-forming material in the chamber, and having an injection port disposed below the film-forming object and opening upward;

A film formation monitor having a crystal vibrator to which the film-forming material evaporated from the evaporation source container is adhered, and obtaining a film-forming rate of the film-forming material evaporated from the evaporation source container with respect to the film-forming object;

A film forming apparatus having a heating source for heating the evaporation source container, and comprising a heating control unit that controls power supplied to the heating source based on the film formation rate acquired by the film formation monitor,

The evaporation source container, in a direction orthogonal to the rotation axis, moves from a spaced position away from the rotation axis to a proximity position close to the rotation axis, and performs a reciprocating movement back to the separation position,

The crystal vibrator is characterized in that it moves so as to maintain a state facing the evaporation source container performing the reciprocating movement.

In order to achieve the above object, the film forming method of the present invention,

By heating an evaporation source container having an ejection opening disposed below the object to be formed in the chamber and opening upward, and evaporating the film-forming material contained in the evaporation source container, the film-forming surface is directed downward in the chamber. A film-forming method of forming a film made of the film-forming material on the film-forming object rotated around a rotation axis perpendicular to the film-forming surface,

A first step of positioning the evaporation source container at a spaced position that does not overlap the film-forming object when the evaporation source container is viewed from the direction of the rotation axis;

A second step of moving the evaporation source container from the spaced position in a direction orthogonal to the rotation axis to a proximity position close to the rotation axis,

Having a third step of moving the evaporation source container from the proximity position to the spaced position,

A crystal vibrator provided in a film formation monitor for acquiring a film formation rate of the film-forming material evaporated in the evaporation source container and the evaporation source container are maintained during the first to third steps. It characterized in that the crystal vibrator is moved so as to be.

According to the present invention, it is possible to achieve both uniform film thickness distribution and improvement in material yield.

1 is a schematic cross-sectional view of a film forming apparatus according to an embodiment of the present invention.
Fig. 2 is a schematic diagram showing a configuration of a film forming rate monitor device in an embodiment of the present invention.
Fig. 3 is a schematic diagram showing a configuration of a crystal monitor head and a shield member in an embodiment of the present invention.
4 is an explanatory diagram of a movable support mechanism of the evaporation source device in the embodiment of the present invention.
Fig. 5 is an explanatory diagram of a difference in a film thickness distribution and a material yield due to a difference in arrangement of a substrate and an evaporation source device.
6 is a diagram showing a film thickness distribution by a film forming process of a film forming apparatus according to an embodiment of the present invention.
Fig. 7 is an explanatory diagram of a configuration when a plurality of evaporation source devices are provided in the embodiment of the present invention.

Hereinafter, preferred embodiments and examples of the present invention will be described with reference to the drawings. However, the following embodiments and examples are merely illustrative of the preferred configuration of the present invention, and the scope of the present invention is not limited to these configurations. In addition, in the following description, the hardware configuration and software configuration of the device, processing flow, manufacturing conditions, dimensions, materials, shapes, etc. are intended to limit the scope of the present invention only to them, unless otherwise specified. It is not.

[Example 1]

With reference to Figs. 1 to 4, a film forming apparatus according to an embodiment of the present invention will be described. The film forming apparatus according to the present embodiment is a film forming apparatus that forms a thin film on a substrate by vacuum evaporation.

The film forming apparatus according to the present embodiment is a thin film on a substrate (including those in which a laminate is formed on a substrate) in the manufacture of various electronic devices such as various semiconductor devices, magnetic devices, and electronic components, and optical components. Is used to form a sediment. More specifically, the film forming apparatus according to the present embodiment is preferably used in the manufacture of electronic devices such as light-emitting elements, photoelectric conversion elements, and touch panels. Among them, the film forming apparatus according to the present embodiment is particularly preferably applicable in the manufacture of organic light-emitting elements such as organic EL (Erectro Luminescence) elements and organic photoelectric conversion elements such as organic thin-film solar cells. In addition, the electronic device in the present invention includes a display device (for example, an organic EL display device) with a light-emitting element, a lighting device (for example, an organic EL lighting device), and a sensor with a photoelectric conversion element ( For example, organic CMOS image sensors) are also included. The film forming apparatus according to this embodiment can be used as a part of a film forming system including a sputtering apparatus or the like.

<Schematic configuration of film forming apparatus>

1 is a schematic diagram showing a configuration of a film forming apparatus 1 according to an embodiment of the present invention. The film forming apparatus 1 includes a vacuum chamber (film forming chamber, evaporation chamber) 200 in which the interior is maintained in a vacuum atmosphere or an inert gas atmosphere such as nitrogen gas by an exhaust device 24 and a gas supply device 25. Have. In addition, in this specification, "vacuum" refers to a state in a space filled with a gas having a pressure lower than atmospheric pressure.

When the substrate 100 as a film-forming object is conveyed into the vacuum chamber 200 by a transfer robot (not shown), it is held by the substrate holding unit 210 provided in the vacuum chamber 200. The substrate holding unit 210 holds the substrate 100 horizontally, and the film-forming surface 100a, which is the surface to be processed, of the substrate 100 faces downward. The substrate holding unit 210 is supported by being suspended above the inside of the vacuum chamber 200 via a rotation shaft 220. The rotation shaft 220 is provided so as to penetrate substantially vertically through the ceiling of the vacuum chamber 200, is axially supported by a bearing or the like with respect to the shaft hole of the ceiling of the vacuum chamber 200, and the gap with the shaft hole is a magnetic fluid seal. It is encapsulated. The rotation shaft 220 rotates by a driving force of a rotation driving unit 230 including a motor or the like provided outside the vacuum chamber 200, and rotates the substrate holding unit 210. As the substrate holding unit 210 as a rotation support part rotates, the substrate 100 rotates around a predetermined rotation center axis (rotation axis Y1) inside the vacuum chamber 200.

In addition, as a specific configuration for holding the substrate 100 by the substrate holding unit 210, a configuration in which the end portion of the substrate 100 is held to be held, or a configuration in which the back surface of the substrate 100 is held by suction Such as, conventionally known configurations can be appropriately adopted. In addition, the film formation surface 100a of the substrate 100 is covered with a mask having an opening pattern corresponding to the thin film pattern formed on the film formation surface 100a (the substrate 100 is placed on the upper surface of the mask). In some cases, a configuration for holding the substrate 100 is employed.

An evaporation source device 300 is provided below the substrate 100 in the vacuum chamber 200. The evaporation source device 300 schematically includes an evaporation source container (crucible) 301 (hereinafter, referred to as a container 301) for accommodating a film forming material (deposition material) 304, and a film forming material 304 accommodated in the container 301. ) And a heater 302 as a heating means (heating source) for heating. The film forming material 304 in the container 301 evaporates in the container 301 by heating by the heater 302, and a nozzle 303 that forms an injection port of the film forming material 304 provided on the container 301 It is ejected out of the container 301 through. The film forming material 304 sprayed out of the container 301 is deposited on the film forming surface 100a of the substrate 100 rotated at a predetermined rotational speed above the apparatus 300.

Further, as the configuration of the container 301, the nozzle 303 is not an essential configuration, and may be a configuration in which only the injection port is opened without the nozzle 303.

The heater 302 has a configuration in which one linear (wire-shaped) heating element that generates heat by energization is wound around the outer periphery of the cylindrical portion of the container 301 a plurality of times. Moreover, it may be a configuration in which a plurality of heating elements are wound. As the heater 302, a metal heating resistor such as stainless steel may be used as the heating element, or a carbon heater or the like may be used.

In addition, the evaporation source device 300 is a reflector and a heat transfer member for increasing the heating efficiency by the heater 302, a frame body and a shutter that accommodates the entire configuration of the evaporation source device 300 including them, although not shown, Etc. may be provided.

The film forming apparatus 1 according to the present embodiment is a means for detecting the vapor amount of the film forming material 304 ejected from the container 301 or the film thickness of a thin film formed on the substrate 100, and is a film forming rate monitor. It has a device (4). The film-forming rate monitor 4 is a crystal monitor head (a part of the film-forming material 304 ejected from the container 301) while the shielding member 42 as a rotating body intermittently repeats the shielded state and the non-shielded state. Attach to the crystal vibrator provided in 41). By detecting the amount of change (reduction) in the resonant frequency (intrinsic frequency) of the crystal vibrator due to the deposition of the film-forming material 304, as a film-forming rate (deposition rate) corresponding to a predetermined control target temperature, the film-forming material per unit time ( 304) adhesion amount (deposition amount) can be obtained. By feeding back this film formation rate to the setting of the control target temperature in heating control of the heater 302, the film formation rate can be arbitrarily controlled. Therefore, by monitoring the discharge amount of the film forming material 304 or the film thickness on the substrate 100 at all times during the film forming process by the film forming rate monitor device 4, high-precision film formation becomes possible.

The control unit (operation processing unit) 20 of the film forming apparatus 1 according to the present embodiment includes a monitor control unit 21 that controls the operation of the monitor unit 40, measures and acquires the film forming rate, and an evaporation source device. It has a heating control part 22 which performs heating control of 300. In addition, the control unit 20, in addition to the rotation of the substrate 100 by the rotation driving unit 230, reciprocating movement of the evaporation source device 300 by the movable support mechanism 50, which will be described later, opening and closing the shutter 60 Controls such as movement operation are also performed.

<Film formation rate monitor device>

2 is a schematic diagram showing a schematic configuration of the film forming rate monitor device 4 according to the present embodiment. As shown in Fig. 2, the film formation rate monitor device 4 according to the present embodiment includes a monitor unit 40 including a monitor head 41, a shield member (chopper) 42, and the like, and a monitor control unit ( 21). The monitor unit 40 includes a servo motor 46 as a rotation drive source of a monitor head 41, a shield member 42, and a crystal holder (rotation support) 44 fitted in the monitor head 41, A servo motor 45 is provided as a rotation driving source of the shield member 42. The monitor control unit 21 includes a shielding member control unit (rotation control unit) 212 that controls rotational driving of the shielding member 42, and a film formation rate acquisition unit that acquires the resonance frequency (change amount of) of the crystal vibrator 43 It has 213 and a holder control part 214 which controls rotational drive of the crystal holder 44.

3 is a schematic diagram showing an arrangement relationship between the monitor head 41 (crystal holder 44) and the shield member 42 when viewed along the respective rotation axis directions. As shown in FIG. 3, inside the monitor head 41, the crystal holder 44 which arranges and supports a plurality of crystal vibrators 43 (43a, 43b) at equal intervals in the circumferential direction is fitted. The monitor head 41 is provided with one monitor opening 41a slightly larger than the crystal vibrator 43, and the crystal holder 44 holds one of the supporting crystal vibrators 43 and the monitor opening 41a. It is supported at a position (rotation phase) exposed to the outside (evaporation source device 300) through.

As shown in FIGS. 2 and 3, the center of the crystal holder 44 is connected to the motor shaft 46a of the servo motor 46 and is rotationally driven by the servo motor 46. Thereby, it is comprised so that the crystal vibrator 43 exposed to the outside through the monitor opening 41a can be sequentially switched. That is, of the plurality of crystal vibrators 43 supported by the crystal holder 44, one crystal vibrator 43a is in a position where the phase overlaps with the monitor opening 41a, and the other crystal vibrator 43b is not used. As a finished or exchangeable crystal vibrator, it is in a hidden position inside the monitor head 41. When the crystal vibrator 43 exposed to the outside through the monitor opening 41a exceeds a predetermined amount of the film-forming material 304 and reaches its service life, the crystal holder 44 rotates and a new crystal vibrator 43 To the exposed position overlapping the monitor opening 41a.

The rotation control of the servo motor 46 by the holder control unit 214 is performed at the rotational position (rotation phase) of the crystal holder 44 detected by the phase position detection means 48 composed of the detection unit 48a and the detected unit 48b. ) On the basis of. Further, as the position (phase) detecting means, a known position sensor such as a rotary encoder may be used.

As shown in FIG. 3, the shield member 42 is a substantially disk-shaped member, its center is connected to the motor shaft 45a of the servo motor 45, and rotationally driven by the servo motor 45. The shielding member 42 is a position where the fan-shaped opening slit (opening portion, non-shielding portion) 42a is off the center of rotation, and the rotational trajectory is provided at a position overlapping the monitor opening 41a of the monitor head 41 .

2 and 3, when the shield member 42 rotates, the relative position (relative phase) of the opening slit 42a with respect to the monitor opening 41a overlaps with the monitor opening 41a (opening It is changed to a position, a non-shielded position) and a position that does not overlap (a closed position, a closed position). As a result, when the area portion of the shielding member 42 excluding the opening slit 42a becomes the shielding portion 42b, and it is at a position (phase) overlapping (covering) the monitor opening 41a, the crystal vibrator ( A shielding state (non-opening state) in which adhesion of the film-forming material 304 to 43a) is impeded. Further, when the opening slit 42a is in a position (phase) overlapping with the monitor opening 41a, it is in an unshielded state (opened state) in which adhesion of the film forming material 304 to the crystal vibrator 43a is allowed.

The rotation control of the servo motor 45 by the shield member control unit 212 is performed by the rotation position (rotation) of the shield member 42 detected by the phase position detection means 47 composed of the detection unit 47a and the detected unit 47b. Phase). Further, as the position (phase) detecting means, a known position sensor such as a rotary encoder may be used.

Although the opening slit 42a is a closed hole in this embodiment, it may have a cutout shape opened at the peripheral end of the shield member 42. In addition, the number of installation may be two or more, and the slit shape is not limited to the fan shape shown in the present embodiment, and various shapes can be adopted. In the case where a plurality of opening slits 42a are provided, they may have different shapes individually.

The crystal resonator 43a is connected to the external resonator 49 via an electrode, a coaxial cable, or the like. The transmission signal generated by applying a voltage between the thin film of the film-forming material 304 deposited on the surface of the crystal resonator 43a and the electrode on the back surface is the resonant frequency (change amount) of the crystal resonator 43 It is transmitted from 49 to the film formation rate acquisition unit 213 and acquired.

Although not shown, the monitor unit 40 is provided with a flow path for flowing coolant for cooling the heat of the motors 45 and 46 serving as heat sources.

In addition, the configuration of the film forming rate monitor device shown here is merely an example, and is not limited thereto, and known various configurations may be appropriately employed.

<heater power supply control>

The amount of heat generated by the heater 302 is controlled by controlling the amount of electric power (current value) supplied to the heater 302 by the heating control unit 22 including a power supply circuit. The power supply amount is adjusted by PID control so that, for example, the temperature detected by the temperature detection means (not shown) is maintained at a predetermined control target temperature suitable for obtaining a desired film formation rate. A thin film having a desired film thickness can be formed on the film-forming surface 100a of the substrate 100 by holding the heating value (power supplied to the heater 302) of the heater 302 capable of maintaining a prescribed film-forming rate for a prescribed time. (Film thickness = film formation rate [Å/S]×time [t]).

The film forming apparatus 1 according to the present embodiment is a method of controlling supply power in the heating control of the heater 302 and is configured to be executed by switching between rate control and average power control. In addition, the power control method is not limited to these.

In the rate control, the control target temperature is changed in a timely manner so that the monitor value (actual value) of the film formation rate acquired by the film formation rate monitor device 4 matches the desired target rate (theoretical value), so that the control target temperature is set. Accordingly, the amount of power supplied to the heater 302 is controlled.

In the present embodiment, the average power control is used as the power control for determining the amount of power supplied to the heater 302 regardless of the monitor value (actual value) of the film formation rate acquired by the film formation rate monitor device 4. In the average power control, it is a control method of controlling the supply of electric power to the heater 302 so as to maintain the target electric energy by using the moving average of the past number sampling of the supplied electric power as the target electric energy. In addition, power control for supplying electric power to the heater 302 may be used so as to maintain a preset electric power amount (target electric power amount). In these power controls, the film thickness is controlled using a theoretical value set based on film formation conditions such as the type of film formation material and the relative speed between the substrate and the evaporation source.

<Features of this embodiment>

The film forming apparatus 1 according to the present embodiment performs a film forming process while moving the evaporation source device 300 relative to the rotating substrate 100, at that time, the evaporation source device 300 and the monitor unit 40 It is characterized in that it does not change the relative position of. In addition, there is a feature in the method of moving the evaporation source device 300 relative to the substrate 100. The evaporation source device 300 is configured to reciprocate between a spaced position spaced apart from the rotation axis of the substrate 100 and a proximity position close to the rotation axis. The separation position is the evaporation source device 300 (the opening of the nozzle 303) when viewed in a direction perpendicular to the film formation surface 100a of the substrate 100 (the direction of the rotation axis Y1 of the substrate 100). ) Is a position away from directly under the substrate 100. The proximity position is a position where the evaporation source device 300 is hidden directly under the substrate 100 when viewed from the same direction, and is a position close to the rotation center of the substrate 100 (rotation axis Y1). During the film forming process, the evaporation source device 300 performs a reciprocating movement from the spaced position to the proximity position and from the close position to the spaced position again at least once. In the meantime, the relative position of the evaporation source device 300 and the monitor unit 40 (the opposite state such as the opposite direction or the opposite distance between the evaporation source device 300 and the crystal vibrator 43) is maintained.

Referring to Figs. 1, 4, 5, and 6, a characteristic configuration of the film forming apparatus 1 according to this embodiment will be described.

4 is a schematic diagram illustrating the configuration of the movable support mechanism 50 of the evaporation source device 300 in the film forming apparatus 1 according to the present embodiment, (a) is a schematic diagram of the movable support mechanism 50 A perspective view, (b) is a schematic plan view illustrating the displacement of the evaporation source device 300 by the movable support mechanism 50, and is a view when viewed along the rotation axis direction of the substrate 100.

The film forming apparatus 1 according to the present embodiment includes an arm (arm part) 51 supporting the evaporation source device 300 and the monitor unit 40, a rotation shaft 52 supporting the arm 51, and a rotation shaft. It includes a movable support mechanism 50 provided with a rotation drive part 53 for rotating 52.

As shown in Fig. 4A, the arm 51 extends in a substantially horizontal direction in the vacuum chamber 200, the evaporation source device 300 is disposed at one end, and a monitor unit ( 40) is placed. The monitor unit 40 is supported by the arm 51 so that the crystal vibrator 43 faces the evaporation source device 300 at a predetermined relative position. The rotation shaft 52 is installed so as to penetrate substantially vertically through the bottom of the vacuum chamber 200, supports the arm 51 at the upper end of the vacuum chamber 200, and the lower end outside the vacuum chamber 200 rotates It is connected to the drive part 53. The rotary shaft 52 is axially supported by a bearing or the like with respect to the bottom shaft hole of the vacuum chamber 200, and the gap with the shaft hole is sealed with a magnetic fluid seal. The rotation driving unit 53 disposed outside the vacuum chamber 200 rotates the rotation shaft 52 by rotation driving force obtained from a power source such as a motor under the control of the control unit 20. The evaporation source device 300 and the monitor unit 40 supported by the arm 51 rotate integrally within the vacuum chamber 200 by the rotation of the rotation shaft 52. The rotation axis (second rotation axis) Y2 of the rotation shaft 52 is parallel to the rotation axis line Y1 of the substrate 100. The evaporation source device 300 draws an arc-shaped trajectory centered on the rotation axis Y2 by the rotation of the rotation shaft 52, and moves in a horizontal direction with respect to the rotation axis Y1 of the substrate 100. (Rotation with rotation axis Y2 as a point) is performed. The rotation axis Y2 which is the swing point of the arm 51 is located between one end where the evaporation source device 300 is disposed and the other end where the monitor unit 40 is disposed.

The solid line in FIG. 4B shows the arrangement configuration of each part when the evaporation source device 300 is in a proximity position close to the rotation axis (rotation axis) Y1 of the substrate 100. When viewed from the direction of the rotation axis Y1, the evaporation source device 300 is directly under the substrate 100, the whole of which is hidden in the substrate 100, and is arranged close to the rotation axis Y1. .

The broken line in FIG. 4B shows the arrangement configuration of each part when the evaporation source device 300 is in a spaced position separated from the rotation axis Y1 of the substrate 100. When viewed from the direction of the rotation axis Y1, the entire evaporation source device 300 is located outside the substrate 100 and is arranged largely away from the rotation axis Y1.

As shown in FIG. 4B, the film forming apparatus 1 according to the present embodiment is a shield for restricting adhesion of the film forming material 4 evaporated from the evaporation source device 300 to the substrate 100. A shutter 60 is provided as a means. The shutter 60 is attached to one end of the arm 61 extending horizontally inside the vacuum chamber 200, and by rotation of the rotation shaft 62 connected to the other end of the arm 61, the vacuum chamber 200 The position can be changed in the horizontal direction within. The mechanism for rotating the rotation shaft 62 is the same as the movable support mechanism 50, and a description thereof is omitted. The shutter 60 is a shield covering (blocking) the opening (ejection port) of the nozzle 303 with respect to the evaporation source device 300 in the spaced position by the rotation of the rotation shaft 62 controlled by the control unit 20 It is configured to be movable to a position (closed position) and an uncovered position (open position).

Preparatory heating to stabilize the evaporation state of the film-forming material 304 before the start of the film-forming process, or after completion of the film-forming process, etc., the film-forming material 304 evaporated from the evaporation source device 300 flies to the substrate 100 , When it is desired to regulate the attachment, the shutter 60 is moved to the shielding position. The heating of the crucible 301 once started is preferably continued until, for example, replenishment of the film-forming material 304 is required so as to maintain the evaporation state of the film-forming material 304 in a state suitable for vapor deposition. That is, even when the substrate 100 is being replaced, heating of the crucible 301 may continue. The shutter 60 is moved to the shielding position in order to regulate the scattering of the film forming material 304 during such a non-film forming step.

The shutter 60 is provided with a cutout (cutout) 60a, and even when the shutter 60 is in the shielding position, the opposing state of the crystal oscillator 43 to the evaporation source device 300 is the cutout 60a. It is configured to be maintained through. That is, it is comprised so that acquisition of the film formation rate of the evaporation source device 300 by the monitor unit 40 can be continued even during a non-film formation process.

5 is a schematic diagram for explaining a difference between a film thickness distribution and a material yield due to a difference in the arrangement of the substrate 100 and the evaporation source device 300. FIG. 5A is a schematic plan view similar to FIG. 4B when the evaporation source device 300 is at a position spaced apart from the rotation axis Y1 of the substrate 100. FIG. 5B is a schematic plan view similar to FIG. 4B when the evaporation source device 300 is in a position close to the rotation axis Y1 of the substrate 100. FIG. 5C is a schematic perspective view showing an arrangement relationship when the evaporation source device 300 is at a position separated from the rotation axis Y1 of the substrate 100. FIG. 5D is a schematic perspective view showing an arrangement relationship when the evaporation source device 300 is in a position close to the rotation axis Y1 of the substrate 100.

In the film forming apparatus 1 according to the present embodiment, the film forming process is started from the relative arrangement of the evaporation source device 300 and the substrate 100 shown in Figs. 5A and 5C. That is, when the evaporation source device 300 is in a spaced position, which is the origin position, and the shutter 60 is in the shielding position, heating of the crucible 301 is started under the control of the control unit 20, and the film is formed. The heating state (evaporation state) of the film-forming material 304 is monitored by the rate monitor 4. When the heating state of the crucible 301 (the evaporation state of the film-forming material 304) is in order, the control unit 20 rotates the substrate 100 at a predetermined rotational speed and moves the shutter 60 from the shielding position. It moves to the unshielded position, and starts the film forming process at the spaced position shown in Fig. 5(a) and Fig. 5(c) (first step).

Then, under the control of the control unit 20, the movable support mechanism 50 starts the rotation of the arm 51, and from the spaced position shown in Figs. 5(a) and 5(c), Fig. 5(b) ), a relative movement of the evaporation source device 300 with respect to the substrate 100 toward the proximity position shown in Fig. 5D is started (second step). During this time as well, the film formation rate of the film formation material 304 is monitored by the film formation rate monitor 4. In addition, the evaporation source device 300 is a proximity position shown in Figs. 5B and 5D, and a position at a predetermined approach distance with respect to the rotation center of the substrate 100 (rotation axis Y1). Reach.

When the evaporation source device 300 reaches the proximity position shown in Figs. 5(b) and 5(d), the movable support mechanism 50 reverses the rotation direction (rotation direction) of the arm 51 Then, the direction of the relative movement of the evaporation source device 300 is reversed toward the separation position shown in Figs. 5A and 5C (3rd step). Even while the evaporation source device 300 moves back to the spaced position shown in Figs. 5A and 5C, the film formation rate of the film formation material 304 is monitored by the film formation rate monitor 4. Then, when the evaporation source device 300 returns to the spaced position shown in Figs. 5A and 5C, the shutter 60 is moved from the unshielded position to the shielded position, and the film forming process is terminated.

Even after the film-forming process is ended as described above, heating of the crucible 301 and monitoring of the film-forming rate by the film-forming rate monitor 4 continue to prepare for the next film-forming process.

6 is a graph showing an experiment result by the inventor of the present application as an example of a film thickness distribution by a film forming process of the film forming apparatus 1 according to the present embodiment. The horizontal axis in Fig. 6 represents the radial position of the film-forming surface 100a of the substrate 100 with the position through which the rotation axis Y1 passes as the origin, and the vertical axis is based on the film thickness of the peak ("1 "), and the film thickness is expressed as a ratio with the peak.

A φ300 mm Si wafer substrate 100 is rotated at 10 to 30 rpm, and the height h from the nozzle 303 (injection port) to the substrate 100 is 300 mm, and the nozzle 303 and the rotation axis at a spaced position (Y1) The distance d1 in the horizontal direction with respect to the head was set to 300 mm, and the distance d2 in the horizontal direction between the nozzle 303 and the rotation axis Y1 at the adjacent position was set to 50 mm.

Overall, the distribution gradually decreases as it deviates from the center (rotation axis (Y1)), but the difference between the film thickness at the center and the outer circumferential end formed in the film formation of the path (one way) from the spaced position to the adjacent position is separated from the adjacent position. It can be seen that the film formation of the path returning to the position is added, thereby reducing. Specifically, the film thickness distribution was reduced from ±6.5% in one way to ±5.0% by reciprocation. In addition, a result was obtained that the material yield by reciprocating film formation was 2.5%.

Here, the experimental results of the present embodiment will be described in comparison with a comparative example in which film formation is performed by fixing the evaporation source device 300 to the substrate 100 as in the present embodiment without moving it with respect to the substrate 100. A case in which film formation was performed by fixing the relative position of the evaporation source device 300 with respect to the substrate 100 at a spaced position shown in FIGS. 5A and 5C is referred to as Comparative Example 1, and FIG. The case where (b) and film formation was performed by fixing at the proximity position shown in FIG. 5(d) was referred to as Comparative Example 2. Comparative Example 1 has an apparatus configuration similar to that of the prior art document that emphasizes the above-described material yield. In addition, Comparative Example 2 has an apparatus configuration similar to that of the prior art in which the uniformity of the above-described film thickness distribution is emphasized.

In Comparative Example 1, since immediately above the evaporation source device 300 is outside the outer circumferential end of the substrate 100, a distribution reaching a peak gently from the center to the outer circumferential end is formed, and the film thickness distribution is ±3.7. In %, better results were obtained than in this example. However, since the area immediately above the evaporation source device 300 in which the ejection amount of the film forming material 304 is relatively large is outside the film forming surface 100a of the substrate 100, the film formation is consumed without contributing to the film formation. The amount of the material 304 was increased, and the material yield was 1.1%, resulting in a lower result than in this embodiment.

In Comparative Example 2, since the evaporation source device 300 is in a position close to the rotation axis Y1, and the film formation surface 100a covers the evaporation source 300 immediately above, the rotation center of the substrate 100 This peak was formed, and a distribution in which the film thickness was decreased due to a steep gradient toward the outer peripheral edge was formed. Since the number of film-forming materials 304 that do not contribute to film-forming decreases, the material yield is 4.2%, resulting in better results than in this embodiment, but the film thickness distribution is ±10.9%, which is lower than in this embodiment.

<Excellent point of this example>

According to this embodiment, as explained in comparison with Comparative Examples 1 and 2, film formation with good balance in terms of film thickness distribution and material yield is possible. That is, due to the reciprocating movement between the spaced position and the adjacent position, the time for the evaporation source device 300 to be located under the substrate 100 during the film formation process (both overlapping when viewed from the vertical direction) is increased, and Comparative Example 1 In comparison, the amount of the film-forming material 304 that does not contribute to film-forming can be reduced. On the other hand, since the time during which the evaporation source device 300 stays at the center of rotation of the substrate 100 (near the rotation axis Y1) during the film formation process is shortened, the bias of the local adhesion amount of the film formation material 304 is reduced, and comparison. Compared to Example 2, fluctuations in the film thickness distribution are suppressed. Therefore, according to the present embodiment, it is possible to achieve both uniform film thickness distribution and improvement in material yield.

In addition, according to this embodiment, while the evaporation source device 300 moves relative to the substrate 100, the monitor unit 40 is also in a relative position with the evaporation source device 300 (a crystal oscillator relative to the evaporation source device 300). It is configured to move so as to maintain the opposite state of (43). Thereby, the monitor environment of the film formation rate can be maintained in a constant state, and rate control with high precision becomes possible. Moreover, in this embodiment, the notch 60a is provided in the shutter 60, and it is comprised so that the film formation rate can be monitored even during a non-film formation process. Accordingly, acquisition of the film formation rate can be continued even during the non-film formation process, and rate control with higher precision becomes possible. For example, it is highly accurate to cope with changes in evaporation state over time due to a change in the capacity of the film forming material 304 in the crucible 301, or temporary change in evaporation state due to occurrence of boulders, etc. Acquisition of the film formation rate becomes possible.

<Other>

In the present embodiment, the number of reciprocating movements between the spaced position and the adjacent position is set to one reciprocation, but the number of reciprocations is not limited. For example, the evaporation source device 300 may be moved at a moving speed faster than the moving speed in the case of one reciprocating, and two or more reciprocating movements may be performed.

In addition, the moving speed in the reciprocating movement of the evaporation source device 300 may be the same or different for each of the going path and the return path. Further, during the reciprocation, the speed may be constant, or may be changed in the middle. That is, it may be appropriately combined with the film forming conditions in the above-described rate control, average power control, and the like, and set appropriately according to the control contents.

In this embodiment, the movable support mechanism 50 is configured to reciprocate the evaporation source device 300 (and the monitor unit 40) on an arc orbit, but is not limited to this configuration. For example, the evaporation source device 300 and the monitor unit 40 are supported at a constant opposite distance at the tip of the arm mechanism capable of stretching and contracting, and the evaporation source device 300 against the substrate 100 by the stretching operation of the arm The configuration may be such that the relative position is changed in a linear trajectory.

In this embodiment, the evaporation source device 300 and the monitor unit 40 are configured to be able to move inside the vacuum chamber 200 integrally by a single movable support mechanism 50, but limited to this configuration. It is not. That is, the mechanism for moving the evaporation source device 300 and the mechanism for moving the monitor unit 40 are separate mechanisms, and both are interlocked to maintain the relative arrangement of the evaporation source device 300 and the monitor unit 40 You may configure it to be.

The configuration of the restricting means for regulating the injection of the film-forming material 304 from the evaporation source device 300 is not limited to the configuration of the shutter 60 shown in this embodiment. At least, the film-forming material 304 sprayed from the injection port of the crucible 301 may be configured to prevent adhering to the film-forming object. That is, even if the configuration is not completely blocked the jetting port, for example, a configuration such as forming a wall that prevents the flight of the film forming material locally only in a direction in which the flight of the film forming material is to be regulated may be used.

As shown in FIG. 7, the present invention can also be applied to a film forming apparatus provided with a plurality of evaporation source devices 300. 7A shows a state in which the three evaporation source devices 300 are in a separate position (origin position), and the three shutters 60 are in each shielding position, that is, a standby in which a film forming process is not performed. It shows the state. FIG. 7B shows a state in which the three evaporation source devices 300 are respectively in a spaced position (origin position), and the three shutters 60 are each in an unshielded position, that is, a state in which the film forming process is started. Is shown. Fig. 7(c) shows a state in which the three evaporation source devices 300 are located in proximity to each other, and are located at the return point in the reciprocating movement of the film forming process.

In addition, although the configuration example shown in FIG. 7 includes three evaporation source devices 300, a configuration including two evaporation source devices 300 or a configuration including four or more may be used.

1: film forming device
100: substrate
20: control unit
200: vacuum chamber (film formation chamber)
300: evaporation source device
301: evaporation source container (crucible)
302: heater (heating source)
303: nozzle
40: monitor unit
50: movable support mechanism
51: cancer
52: rotating shaft
53: rotation drive unit
60: shutter
60a: notch

Claims (8)

Chamber,
A rotation support portion rotatably supporting a film-forming object about a rotation axis perpendicular to the film-forming surface in the chamber, with the film-forming surface facing downward;
An evaporation source container containing a film-forming material in the chamber, and having an injection port disposed below the film-forming object and opening upward;
A film formation monitor having a crystal vibrator to which the film-forming material evaporated from the evaporation source container is adhered, and obtaining a film-forming rate of the film-forming material evaporated from the evaporation source container with respect to the film-forming object;
A film forming apparatus having a heating source for heating the evaporation source container, and comprising a heating control unit that controls power supplied to the heating source based on the film formation rate acquired by the film formation monitor,
The evaporation source container, in a direction orthogonal to the rotation axis, moves from a spaced position away from the rotation axis to a proximity position close to the rotation axis, and performs a reciprocating movement back to the separation position,
The crystal vibrator is moved so as to maintain an opposing state with the evaporation source container performing the reciprocating movement. The method of claim 1,
The separation position is a position where the evaporation source container does not overlap the film-forming object when viewed from the direction of the rotation axis. The method according to claim 1 or 2,
And a movable support mechanism for integrally supporting the evaporation source container and the monitor unit provided with the crystal vibrator and moving the inside of the chamber. The method of claim 3,
The movable support mechanism has an arm portion extending in a direction orthogonal to the second rotation axis, capable of swinging a second rotation axis parallel to the rotation axis of the film-forming object to a point in the chamber,
The film forming apparatus, wherein the evaporation source container is disposed on one side of the arm portion with respect to the second rotational shaft, and the monitor unit is disposed on the other side. The method according to any one of claims 1 to 4,
And a shutter configured to be movable to a closed position covering the injection port and an open position not covered when the evaporation source container is in the spaced position. The method of claim 5,
The shutter, when in the closed position, has a notch that allows attachment of the film forming material evaporated from the evaporation source container to the crystal vibrator. The method according to any one of claims 1 to 6,
A film forming apparatus comprising a plurality of each of the evaporation source container and the film forming monitor. By heating an evaporation source container having an ejection opening disposed below the object to be formed in the chamber and opening upward, and evaporating the film-forming material contained in the evaporation source container, the film-forming surface is directed downward in the chamber. A film-forming method of forming a film made of the film-forming material on the film-forming object rotated around a rotation axis perpendicular to the film-forming surface,
A first step of positioning the evaporation source container at a spaced position that does not overlap the film-forming object when the evaporation source container is viewed from the direction of the rotation axis;
A second step of moving the evaporation source container from the spaced position in a direction orthogonal to the rotation axis to a proximity position close to the rotation axis,
Having a third step of moving the evaporation source container from the proximity position to the spaced position,
A crystal vibrator provided in a film formation monitor for acquiring a film formation rate of the film-forming material evaporated in the evaporation source container and the evaporation source container are maintained during the first to third steps. The film forming method, characterized in that the crystal vibrator is moved so as to be able to do so.

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