KR20160115717A - Sputtering apparatus and sputtering method - Google Patents

Abstract

The present invention provides a sputtering apparatus which forms an indium tin oxide (ITO) film having high-flatness and low-resistance, and a sputtering method. The sputtering power supplied to a pair of rotary magnetron cathodes is less than or equal to 1.5 1.5 kW/m, thereby the flatness of the ITO film formed in a state that a low inductance antenna (LIA) supports sputtering is higher than the flatness of the ITO film formed in a state the LIA does not support sputtering. Therefore, the present invention enables the formation of the ITO film having high-flatness. And, the resistivity of the ITO film is less than or equal to 120 cm.

Description

[0001] SPUTTERING APPARATUS AND SPUTTERING METHOD [0002]

The present invention relates to a sputtering apparatus and a sputtering method.

As the transparent electrode (anode) of the organic EL device, an ITO (Indium Tin Oxide) film is generally used.

When the flatness of the ITO film is low, the protruding portion of the ITO film may pierce a part of the organic EL forming layer in its thickness direction. As a result, the opened point becomes a dark spot on the organic EL light emitting surface, and the amount of light decreases or disappears in the dark spot. When the flatness of the ITO film is particularly low, the protruding portion of the ITO film sometimes penetrates all of the organic EL forming layer (multiple layers). As a result, a short circuit occurs between the anode and the cathode of the organic EL element at this penetrating point.

When the electrical resistivity of the ITO film is high, it is necessary to form the ITO film with a thicker film thickness than when the electrical resistivity of the ITO film is low. As a result, the transmittance of light in the ITO film is lowered, and the light amount of the entire organic EL light emitting surface is lowered.

Japanese Patent Publication No. 3865358 Japanese Patent Publication No. 3797317

From these viewpoints, a technology for forming an ITO film having a high flatness and a low resistivity is required. For example, Patent Document 1 discloses a technique for forming an ITO film having a low resistivity and excellent flatness by performing crystallization annealing in the air after deposition of an amorphous ITO film. Patent Document 2 discloses a technique of producing a transparent conductive film having a high flatness and a low resistivity by using a special sputtering target material obtained by combining indium oxide powder and tungsten oxide powder.

Although the field of organic EL has been described above as an example, the technology of forming an ITO film having a high flatness and a low resistivity is also required in various fields other than organic EL such as semiconductor field, flat panel display field, and solar cell field Technology.

It is therefore an object of the present invention to provide a sputtering apparatus and a sputtering method for forming an ITO film having a high flatness and a low resistivity.

A sputtering apparatus according to a first aspect of the present invention is a sputtering apparatus for sputtering an ITO (Indium Tin Oxide) film on a main surface of a substrate to be transported, the apparatus comprising: a vacuum chamber for forming a processing space therein; A reactive gas supply unit for supplying a reactive gas to the processing space; at least one plasma processing unit for performing a plasma process in the processing space; and a plasma processing unit for supplying a reactive gas to the at least one plasma processing unit And a transport mechanism for transporting the substrate along a transport path surface including at least one to-be-coated film formation point facing each other, wherein each of the at least one plasma processing sections is cylindrical and has an outer peripheral surface of indium (In) ) And two rotating cathodes coated with a target material containing oxygen (O) in a predetermined distance in the processing space A rotating unit rotating the two rotating cathodes about respective central axes, sputter power supplying means for supplying sputter power of 1.5 kW / m or less to each of the two rotating cathodes, Two magnetic field generating units respectively accommodated in the rotating cathodes to form a magnetic field in the vicinity of the outer circumferential surfaces of the rotating cathodes and at least two magnetic field generating units for generating inductively coupled plasma in a space including a portion in which the magnetic field is formed, One LIA (Low Inductance Antenna), and a high-frequency power supply means for supplying high-frequency power to the at least one LIA.

The sputtering apparatus according to the second aspect of the present invention is the sputtering apparatus according to the first aspect of the present invention, wherein the sputter power supply means supplies sputter power of 1.0 kW / m or less to the two rotating cathodes .

The sputtering apparatus according to the third aspect of the present invention is the sputtering apparatus according to the second aspect of the present invention, wherein the sputter power supply means supplies sputter power of 0.5 kW / m or more to the two rotating cathodes do.

A sputtering apparatus according to a fourth aspect of the present invention is characterized in that the sputtering apparatus according to the first aspect of the present invention further comprises a heating section for heating the substrate to 200 ° C or higher.

A sputtering apparatus according to a fifth aspect of the present invention is the sputtering apparatus according to the first aspect of the present invention, wherein the ITO film is used as an anode of the organic EL element.

A sputtering apparatus according to a sixth aspect of the present invention is the sputtering apparatus according to any one of the first to fifth aspects of the present invention, comprising: a first measuring unit for measuring a concentration of the reactive gas in the vacuum chamber; A second measuring unit for measuring a concentration of the water vapor in the vacuum chamber; a second measuring unit for measuring a concentration of the reactive gas in the sputtering chamber to a predetermined first target value, And a control unit for performing feedback control of the reactive gas supply unit based on a result of measurement by the first measuring unit and for controlling the concentration of the water vapor during the sputter deposition to a predetermined second target value, And a control unit for feedback-controlling the supply unit.

The sputtering apparatus according to the seventh aspect of the present invention is the sputtering apparatus according to the sixth aspect of the present invention, wherein the resistivity of the ITO film formed is different from that of the first A first step of setting a concentration of the reactive gas when the concentration of the reactive gas becomes smaller than a threshold value as the first target value; and a step of setting the concentration of the reactive gas under the feedback control with the concentration of the reactive gas as the first target value, And the second step of setting the concentration of the water vapor as the second target value when the flatness of the deposited ITO film becomes higher than the second threshold value is executed based on the result of each film formation.

A sputtering apparatus according to an eighth aspect of the present invention is the sputtering apparatus according to the seventh aspect of the present invention, wherein the first target value is a value obtained by subtracting the resistance value of the ITO film when the resistivity of the ITO film is the smallest And is a concentration of the reactive gas.

The sputtering apparatus according to the ninth aspect of the present invention is the sputtering apparatus according to the seventh aspect of the present invention, wherein the second target value is a value obtained by subtracting, from the film formation result of the second step, And is a concentration of water vapor.

A sputtering method according to a tenth aspect of the present invention is a sputtering method using a device including a vacuum chamber for forming a process space therein and at least one plasma processing section for performing a plasma process in the process space, Wherein at least one of the at least one plasma processing portion is cylindrical and the outer peripheral surface thereof contains indium (In), tin (Sn), and oxygen (O) A pair of cathodes which are disposed opposite to each other with a predetermined distance in the processing space, two magnetic field forming units which form a magnetic field in the vicinity of the outer peripheral surface, At least one LIA (Low Inductance Antenna) for generating inductively coupled plasma in a space including a portion where a magnetic field is formed, The method includes: a sputter gas supplying step of supplying a sputter gas to the processing space; a reactive gas supplying step of supplying a reactive gas to the processing space; a rotating step of rotating each rotating cathode around each central axis; A high frequency electric power supply step of supplying a high frequency electric power to the at least one LIA; and a high frequency electric power supply step of supplying at least one And a transporting step of transporting the substrate along a transport path surface including a film formation point.

A sputtering method according to an eleventh aspect of the present invention is the sputtering method according to the tenth aspect of the present invention, wherein the sputtering power supply step supplies sputter power of 1.0 kW / m or less to each of the rotating cathodes do.

The sputtering method according to the twelfth aspect of the present invention is the sputtering method according to the eleventh aspect of the present invention, wherein the sputtering power supply step supplies sputter power of 0.5 kW / m or more to each of the rotating cathodes .

A sputtering method according to a thirteenth aspect of the present invention is the sputtering method according to the tenth aspect of the present invention, characterized by further comprising a heating step of heating the substrate to 200 占 폚 or higher.

A sputtering method according to a fourteenth aspect of the present invention is the sputtering method according to the tenth aspect of the present invention, wherein the ITO film is used as an anode of an organic EL device.

A sputtering method according to a fifteenth aspect of the present invention is the sputtering method according to any one of the tenth to fourteenth aspects of the present invention, the sputtering method comprising: a first measuring step of measuring a concentration of the reactive gas in the vacuum chamber; And a second measuring step of measuring a concentration of the water vapor in the vacuum chamber, wherein in the reactive gas supplying step, the concentration of the reactive gas during the sputtering film formation The supply of the reactive gas is feedback-controlled based on the measurement result by the first measurement unit so that the concentration of the water vapor during the sputter deposition is lower than the second target value The supply of the water vapor based on the measurement result by the second measurement unit Characterized in that the feedback control.

A sputtering method according to a sixteenth aspect of the present invention is the sputtering method according to the fifteenth aspect of the present invention, wherein, as the preparation step of setting the first target value and the second target value, the sputtering method is carried out under the condition that the concentration of the reactive gas is different A first step of setting the concentration of the reactive gas when the resistivity of the deposited ITO film becomes smaller than the first threshold value as the first target value based on the deposited film formation results; And setting the concentration of the water vapor when the flatness of the deposited ITO film becomes higher than the second threshold value as the second target value based on the result of each film formation performed under the condition that the concentration of the water vapor is different under the feedback control of 2 < / RTI > process.

The sputtering method according to the seventeenth aspect of the present invention is the sputtering method according to the sixteenth aspect of the present invention, wherein the first target value is a sputtering rate of the ITO film when the resistivity of the ITO film is the smallest And is a concentration of the reactive gas.

The sputtering method according to the eighteenth aspect of the present invention is the sputtering method according to the sixteenth aspect of the present invention, wherein the second target value is a sputtering rate of the ITO film when the flatness of the ITO film is the highest, And is a concentration of water vapor.

In the present invention, a rotary-type magnetron cathode pair is used. In the rotary-type magnetron cathode pair, the nodule is not generated well during the film forming process as compared with the playner-type magnetron cathode. For this reason, in the present invention, various problems (such as high resistivity of the ITO film, particles arising in the ITO film due to occurrence of arcing, etc.) arising from the generation of nodules do not occur well.

Further, in the present invention, LIA (Low Inductance Antenna: registered trademark of EMD Corporation) generates an inductively coupled plasma in a space including a portion where a magnetic field is formed by the magnetic field forming portion in the processing space. Thereby, the inductively coupled plasma by the LIA contributes to the sputter processing by the magnetron cathode pair. Therefore, the deposition rate is improved, and an ITO film having a lower resistivity can be formed, which is preferable.

In the present invention, the sputter power supplied to the magnetron cathode pair of the rotary type is 1.5 kW / m or less. For this reason, the flatness of the ITO film deposited in the mode in which the LIA supports the sputter processing is higher than the flatness of the ITO film deposited in the mode in which the LIA does not support the sputter processing. As a result, in the present invention, it is preferable to form an ITO film having a high flatness. Also, the resistivity of the ITO film is preferably a low resistivity of 120 占 cm or less.

1 is a schematic cross-sectional view showing a configuration example of a sputtering apparatus.
2 is a schematic cross-sectional view showing the periphery of the plasma processing section.
3 is a side view showing an inductively coupled antenna.
4 is a perspective view showing the periphery of the plasma processing section.
5 is a graph showing the relationship between the sputtering power and the resistivity of the ITO film.
FIG. 6 is a graph showing the relationship between the amount of sputtering in the case where five kinds of sputter power are supplied in the embodiment in which the LIA supports sputter processing and the case where five kinds of sputter power are supplied in the embodiment in which the LIA does not support the sputter processing. And the film surface is enlarged and shown.
7 is a graph showing the relationship between the deposition thickness of the ITO film and the carrier density, the relationship between the deposition thickness and the hole mobility of the ITO film, and the deposition thickness and resistivity of the ITO film.
8 is a graph showing the relationship between the DC sputter power supplied to the magnetron cathode pair of the rotary type and the flatness of the ITO film surface.
9 is a graph showing the relationship between the heating temperature of the substrate by the heating section and the flatness of the surface of the ITO film.
10 is a schematic cross-sectional view showing a configuration example of the sputtering apparatus according to the second embodiment.
11 is a diagram showing the relationship between the resistivity of the ITO film, the flatness of the surface of the ITO film, and the concentration of each gas in the processing space.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant description is omitted. The following embodiments are illustrative of the present invention and do not limit the technical scope of the present invention. In the drawings, the dimensions and numbers of the portions are exaggerated or simplified for ease of understanding. In the drawings, XYZ orthogonal coordinate axes may be attached to explain directions. The + Z direction in the coordinate axis is the vertical upward direction, and the XY plane is the horizontal plane.

<Embodiment 1>

<1.1 Overall Configuration of Sputtering Apparatus 1>

1 is a schematic cross-sectional view schematically showing a schematic structure of a sputtering apparatus 1. Fig. 2 is a schematic cross-sectional view showing the plasma processing section 50 and the periphery thereof. 3 is a side view showing an example of the inductively coupled antenna 151 of the plasma processing unit 50. Fig. 4 is a perspective view showing the plasma processing unit 50 and its periphery.

The sputtering apparatus 1 is an apparatus for sputtering an ITO film on the main surface of a substrate 91 to be transported. The substrate 91 is made of, for example, a glass substrate or the like.

The sputtering apparatus 1 includes a chamber 100 (vacuum chamber), a plasma processing unit 50 disposed therein, a transport mechanism 30 for transporting the substrate 91, And a control unit (190) for controlling the components in a general manner. The chamber 100 is a hollow member having a rectangular parallelepiped shape. The chamber 100 is arranged such that the upper surface of the bottom plate is in a horizontal posture. The X axis and the Y axis are axes parallel to the side wall of the chamber 100, respectively.

The sputtering apparatus 1 further includes a chimney 60 which is a tubular shielding member disposed to surround the plasma processing unit 50. The chimney 60 has a function as a shield for limiting the range of plasma generated in the plasma processing unit 50 and the scattering range of the sputtered particles sputtered from the target and an atmosphere cutoff function for blocking the atmosphere inside the chimney from the outside. The processing space (V) is a space defined by the chimney (60) and surrounding the plasma processing unit (50). For this reason, the chamber 100 has a processing space V therein.

In the chamber 100, a horizontal transport path surface L is defined above the chimney 60. The extending direction of the transport path surface L is the X axis direction, and the base material 91 is transported along the X axis direction.

The sputtering apparatus 1 also includes a plate-shaped heating section 40 for heating the substrate 91 conveyed in the chamber 100. The heating section 40 is constituted by, for example, a sheath heater arranged on the upper side of the conveying path surface L.

A gate 160 for carrying the substrate 91 into the chamber 100 is formed at the end of the transfer path L of the chamber 100 on the -X side. On the other hand, at the end on the + X side of the transport path surface L of the chamber 100, a gate 161 for transporting the substrate 91 out of the chamber 100 is formed. In addition, openings of other chambers such as a load lock chamber and an unload lock chamber can be connected to the both ends in the X direction of the chamber 100 in a sealed manner. Each of the gates 160 and 161 is configured to be openable and closable.

A high vacuum exhaust system 170 is connected to the chamber 100 so that the internal space of the chamber 100 can be decompressed to a vacuum state. The high vacuum exhaust system 170 includes, for example, a vacuum pump, an exhaust pipe, and an exhaust valve, which are not shown. One end of the exhaust pipe is connected to the vacuum pump and the other end is connected to the inner space of the chamber 100. Further, the exhaust valve is formed in the middle of the path of the exhaust pipe. Specifically, the exhaust valve is a valve that can automatically adjust the flow rate of gas flowing through the exhaust pipe. In this configuration, when the exhaust valve is opened while the vacuum pump is operated, the internal space of the chamber 100 is exhausted. The high vacuum exhaust system 170 is controlled by the control unit 190 to maintain the pressure in the processing space V at a predetermined process pressure.

The conveying mechanism 30 includes a plurality of pairs of conveying rollers 31 arranged in opposition to each other with the conveying path surface L interposed therebetween in the Y direction within the chamber 100, And a driving unit (not shown). The conveying rollers 31 are formed in a plurality of pairs along the X direction which is the extending direction of the conveying path surface L. In Fig. 1, two rollers positioned on the front side (-Y side) of the two pairs of conveying rollers 31 are drawn.

The substrate 91 is detachably held under the carrier 90 by a claw-like member (not shown) formed on the lower surface of the carrier 90. [ The carrier 90 is constituted by a plate-like tray or the like. In addition, the carrier 91 may be retained in the carrier 90 in various modes other than those of the present embodiment. For example, even if the substrate 91 is held in a state in which the lower surface of the substrate 91 can be formed by fitting the substrate 91 into the hollow portion of the plate-shaped tray having the hollow portion penetrating in the vertical direction none.

When the carrier 90 on which the base material 91 is disposed is introduced into the chamber 100 through the gate 160, each of the conveying rollers 31 is moved in the vicinity of the end edge of the carrier 90 As shown in FIG. Each carrier roller 31 is rotated synchronously by a driving unit (not shown), whereby the carrier 90 and the base material 91 held by the carrier 90 are conveyed along the conveying path surface L. [ In this embodiment, each of the conveying rollers 31 is rotatable in both the clockwise and counterclockwise directions, and the substrate 90 held by the carrier 90 and the carrier 90 is conveyed in both directions The mode will be described. The transport path surface L includes a film formation point P opposed to the plasma processing portion 50. For this reason, a film forming process is performed at a point located on the film formation point P in the main surface of the substrate 91 conveyed by the transport mechanism 30. [

The sputtering apparatus 1 includes a sputter gas supplying unit 510 for supplying a sputter gas such as argon gas as an inert gas to the processing space V and a reactive gas supplying unit 52 for supplying a reactive gas such as oxygen gas, And a supply unit 520. Thus, a mixed atmosphere of a sputter gas and a reactive gas such as oxygen is formed in the processing space (V).

Specifically, the sputter gas supply unit 510 includes, for example, a sputter gas supply source 511 as a supply source of the sputter gas and a pipe 512. The pipe 512 is connected to each nozzle 514, one end of which is connected to the sputter gas supply source 511 and the other end is in communication with the processing space V. A valve 513 is formed in the middle of the path of the pipe 512. The valve 513 adjusts the amount of the sputter gas supplied to the processing space V under the control of the control unit 190. [ The valve 513 is preferably a valve capable of automatically regulating the flow rate of the gas flowing through the piping. Specifically, it is preferable that the valve 513 includes a mass flow controller or the like.

Specifically, the reactive gas supply unit 520 includes, for example, a reactive gas supply source 521 serving as a reactive gas supply source and a pipe 522. The piping 522 is connected to the reactive gas supply source 521 at one end and is divided into a plurality of nozzles 12 (see FIG. 4 (Six nozzles 12 in total, three each on the + X side and the -X side). A valve 523 is formed in the path of the pipe 522. The valve 523 adjusts the amount of the reactive gas supplied to the process space V under the control of the control unit 190. [

Each of the nozzles 12 is formed so as to extend in the Y direction in the region on the + Z side in the processing space V. The other end of the pipe 522 is connected to each outer end of each of the X-direction cross-sections of the respective nozzles 12. Each of the nozzles 12 is connected to the other end of the pipe 522 which is open at each end surface and is branched into a plurality of channels in the nozzle. The tip ends of the respective flow paths are opened to the respective inner end surfaces of both the X-direction end surfaces of the nozzle 12, and a plurality of discharge ports 11 are formed in the respective end surfaces.

On the lower side of each nozzle 12 on the -X side, a probe 13 of an optical fiber is formed. Further, a spectroscope 14 capable of measuring the spectral intensity of plasma emission incident on the probe 13 is formed. The spectroscope 14 is electrically connected to the control unit 190 and the measured value of the spectroscope 14 is supplied to the control unit 190. [ The control unit 190 controls the valve 523 by the plasma emission monitor (PEM) method based on the output of the spectroscope 14 so that the reactive gas supplied from the reactive gas supply unit 520 into the chamber 100 Is controlled. The valve 523 is preferably a valve capable of automatically regulating the flow rate of the gas flowing through the pipe, and it is preferable that the valve 523 is configured to include, for example, a mass flow controller.

The respective components of the sputtering apparatus 1 are electrically connected to the control unit 190 included in the sputtering apparatus 1, and the respective components are controlled by the control unit 190. [ Specifically, for example, the control unit 190 includes a CPU for carrying out various arithmetic processing, a ROM for storing programs and the like, a RAM serving as a work area for arithmetic processing, a hard disk for storing programs and various data files, And a data communication unit having a data communication function via a bus line or the like are connected to each other by a general FA computer. The control unit 190 is connected to an input unit including a display for performing various displays, a keyboard, a mouse, and the like. In the sputtering apparatus 1, a sputtering process is performed under the control of the control unit 190. [

&Lt; 1.2 Plasma Treatment Unit 50 &gt;

Hereinafter, the plasma processing unit 50 for executing the plasma processing in the processing space V will be described in detail.

The plasma processing unit 50 includes two rotating cathodes 5 and 6 and two rotating units 19 for rotating the two rotating cathodes 5 and 6 around their respective central axes and two rotating cathodes 5 And 6 (magnetic field forming units) respectively accommodated in the magnet units 21 and 22, respectively.

The rotating cathodes 5 and 6 are arranged as a pair of cathodes facing each other with a certain distance in the X direction in the processing space V. By forming the rotating cathodes 5 and 6 in this manner in this manner, the film quality in which radicals are concentrated more on the film formation point P on the substrate 91 can be improved.

The plasma processing section 50 includes a sputter power source 163 (sputter power supply means) for supplying sputter power to the two rotating cathodes 5 and 6, a plurality of inductively coupled antennas 151, A high frequency power supply 153 (high frequency power supply means) for supplying high frequency power to the inductively coupled antenna 151 is additionally provided.

The magnet unit 21 (22) forms a magnetic field (a static magnetic field) in the vicinity of itself in the outer peripheral surface of the rotating cathode 5 (6). Each inductively coupled antenna 151 is an LIA that generates inductively coupled plasma in a space including a magnetic field formed by the magnet units 21 and 22 in the processing space V. [ The inductively coupled plasma is a high density plasma having a spatial density of electrons of 3 x 10 ¹⁰ atoms / cm 3 or more.

The rotating cathode 5 (6) includes a tubular base member 8 extending in the Y direction perpendicular to the carrying direction in the horizontal plane, and a cylindrical target 16 covering the outer periphery of the base member 8, As shown in FIG. The base member 8 is a conductor and a material containing indium (In), tin (Sn), and oxygen (O) for ITO film formation is used as a material of the target 16. The rotating cathode 5 (6) may not include the base member 8 but may be constituted by the cylindrical target 16. The target 16 is formed, for example, by compression molding powder of a target material into a cylindrical shape, and thereafter inserting and brazing the base member 8.

In the present specification, when the rotating cathodes 5 and 6 formed side by side and the magnet units 21 and 22 disposed in each of them are integrally expressed, they are called a magnetron cathode pair.

Both end portions in the direction of the center axis 2 (3) of each base member 8 are closed by a lid portion formed with a circular opening at the center. The length of the rotating cathode 5 (6) in the direction of the central axis 2 (3) is set to, for example, 1,400 mm, and the diameter is set to, for example, 150 mm.

The plasma processing section 50 further includes two pairs of seal bearings 9 and 10 and two cylindrical support rods 7. Each pair of the seal bearings 9 and 10 is formed with the rotating cathode 5 (6) therebetween in the longitudinal direction (Y direction) of the rotating cathode 5 (6). Each of the seal bearings 9 and 10 has a pedestal formed upright from the upper surface of the bottom plate of the chamber 100 and a substantially cylindrical portion formed on the upper portion of the pedestal.

One end of each support rod 7 is supported by a cylindrical portion of the seal bearing 9 and the other end is supported by a cylindrical portion of the seal bearing 10. Each supporting rod 7 is inserted into the rotating cathode 5 (6) from the opening of the lid portion at one end of the base member 8 so that the rotating cathode 5 (6) is moved along the central axis 2 (3) And comes out of the rotary cathode 5 (6) from the opening of the lid portion at the other end of the base member 8.

The magnet unit 21 (22) includes a yoke 25 (supporting plate) formed of a magnetic material such as an investment steel and a plurality of magnets (a central magnet 23a , And a surrounding magnet 23b).

The yoke 25 is a flat plate member and extends in the longitudinal direction (Y direction) of the rotary cathode 5 so as to face the inner peripheral surface of the rotary cathode 5 (6). A central magnet 23a extending in the longitudinal direction of the yoke 25 is disposed on the center line along the longitudinal direction of the yoke 25 on the surface of the yoke 25 opposed to the inner peripheral surface of the rotating cathodes 5, . An annular (non-endless) peripheral magnet 23b surrounding the center magnet 23a is additionally formed at the outer edge of the surface of the yoke 25. The central magnet 23a and the peripheral magnet 23b are constituted by, for example, permanent magnets.

The polarities of the target 16 side of each of the center magnet 23a and the peripheral magnet 23b are different from each other. The polarities of the two magnet units 21 and 22 are complementary. For example, in the magnet unit 21, the polarity of the center magnet 23a on the side of the target 16 becomes the N pole, the polarity of the peripheral magnet 23b becomes the S pole, while on the magnet unit 22, The polarity of the center magnet 23a on the side of the target 16 becomes the S pole and the polarity of the peripheral magnet 23b becomes the N pole.

One end of the fixing member 27 is joined to the back surface of the yoke 25. The other end of the fixing member 27 is joined to the support rod 7. Thereby, the magnet units 21, 22 are connected to the support rods 7. In this embodiment, the magnet units 21 and 22 constituting the pair of magnetron cathodes are fixed in a state of being rotated by a predetermined angle in the + Z direction approaching the film formation point P from the positions facing each other. Therefore, a relatively strong static magnetic field is formed between the rotating cathodes 5, 6 and between the magnet units 21, 22 in the space on the side of the film formation point P side.

A rotating portion 19 having a motor and gears (not shown respectively) for transmitting the rotation of the motor is formed on the base of each seal bearing 9. A gear (not shown) is formed around the opening of the lid portion on the + Y side of the base member 8 of the rotating cathodes 5 and 6 so as to mesh with the gears of the rotating portions 19.

Each rotary section 19 rotates the rotary cathode 5 (6) about the center axis 2 (3) by the rotation of the motor. More specifically, the rotating portion 19 is disposed so that the portions of the outer circumferential surfaces of the rotating cathodes 5 and 6 facing each other are moved from the side of the inductively coupled antenna 151 toward the side of the substrate 91, 2, 3) of the rotating cathode 5, 6 in the opposite direction to each other. The rotation speed is set to, for example, 10 to 20 revolutions / minute, and is constantly rotated in the rotation speed and the rotation direction during the film forming process. The rotating cathodes 5 and 6 are cooled appropriately by circulating cooling water through the seal bearing 10 and the support rod 7 inside.

The electric wires connected to the sputtering power source 163 are branched into two and guided into the respective seal bearings 10 of the rotating cathodes 5, 6. At the tip of each electric wire, a brush is formed which contacts the lid portion on the -Y side of the base member 8 of the rotating cathodes 5, 6. The sputter power source 163 supplies sputter electric power to the base member 8 via this brush. In the present embodiment, the sputter power source 163 supplies the rotating cathodes 5 and 6 with DC power of negative potential. Alternatively, for example, the power source 163 for sputtering may supply alternating-current sputtering power having opposite phases to the rotating cathodes 5 and 6, and the power source 163 for sputtering may be applied to the rotating cathodes 5 and 6 ) May be supplied to the non-inverting input terminal and the non-inverting input terminal.

A plasma of sputter gas is generated on the surface of each target 16 of the processing space V when the sputtering power is supplied to each base member 8 (and further, each target 16). This plasma is trapped at high density in the space between the rotating cathodes 5 and 6 and on the side of the film forming point P by the static magnetic field formed by the magnet units 21 and 22. [ In this specification, the plasma that is densified due to the magnetic field confinement effect is called a magnetron plasma. In the embodiment in which the magnetron cathode pair generates the magnetron plasma as in the present embodiment, the plasma becomes denser than when one magnetron cathode generates the magnetron plasma. Therefore, the embodiment of the present embodiment is preferable from the viewpoint of the improvement of the film formation rate.

The plurality of inductively coupled antennas 151 are arranged at intervals in the longitudinal direction (Y direction) of the rotating cathodes 5, 6 at intervals between the rotating cathodes 5, 6 in the bottom plate of the chamber 100 And are arranged in a line. In the example of Fig. 4, the case where the number of the inductively coupled antenna 151 is five is described, but the number thereof can be appropriately changed according to the length of the rotating cathode 5 (6).

Each of the inductively coupled antennas 151 is covered with a dielectric protective member 152 made of quartz glass or the like and is formed so as to penetrate through the bottom plate of the chamber 100. A pair of nozzles 514 for introducing the sputter gas supplied from the sputter gas supply source 511 to the processing space V are formed on the ± X side of each inductively coupled antenna 151.

As shown in Fig. 3, each of the inductively coupled antennas 151 is formed by bending a metal pipe-shaped conductor into a U-shape, and the bottom plate of the chamber 100 is connected to the U- And is protruded from the inside of the processing space V through the through-hole. The inductively coupled antenna 151 is appropriately cooled by circulating cooling water inside.

One end of each inductively coupled antenna 151 is electrically connected to the high frequency power source 153 via a matching circuit 154. The other end of each inductively coupled antenna 151 is grounded. The high frequency power supply 153 supplies high frequency power to each inductively coupled antenna 151 so that inductively coupled plasma is generated in the processing space V.

When high frequency power is supplied from the high frequency power supply 153 to the inductively coupled antenna 151, a high frequency induction magnetic field is generated around the inductively coupled antenna 151, and the sputter gas and the reactive gas Inductively coupled plasma (ICP) is generated.

Each inductively coupled antenna 151 generates inductively coupled plasma in a space including a portion where a magnetic field is formed by the magnet units 21 and 22 in the processing space V. [ As a result, the magnetron plasma generated by the pair of magnetron cathodes and the inductively coupled plasma generated by the inductively coupled antenna 151 overlap each other to form a mixed plasma. The high-density inductively coupled plasma generated by the inductively coupled antenna 151 is also reflected by the magnet units 21 and 22 together with the magnetron plasma by the magnetic field formed in the vicinity of the outer circumferential surface of the rotating cathodes 5 and 6, Contributes to the sputtering.

When the inductively coupled plasma is contributed to the sputtering as described above, the sputter voltage can be lowered even if the sputtering power supplied to the rotating cathodes 5 and 6 is the same, compared with the case where the inductively coupled plasma is not contributed Can be lowered). As a result, the film forming process is performed at a high film forming rate, with the detrimental effect of recoil argon and negative ions flying from the target 16 on the surface of the substrate 91 to be coated.

As described above, the inductively coupled antenna 151 is U-shaped. Such U-shaped inductively coupled antenna 151 is equivalent to an inductively coupled antenna having a number of turns of less than one week and has a lower inductance than an inductively coupled antenna having a number of turns of one week or more. Therefore, the high frequency voltage generated at both ends of the inductively coupled antenna 151 is reduced, and the high frequency oscillation of the plasma potential accompanying the electrostatic coupling to the generated plasma is suppressed. As a result, excessive electron loss accompanying the plasma potential fluctuation with respect to the earth potential is reduced, and the plasma potential is particularly suppressed to be low. This makes it possible to reduce the damage to the base 91.

The sputtering apparatus 1 described above can be manufactured by sputtering a target 16 of ITO that covers the outer periphery of the rotating cathodes 5 and 6 by introducing a sputter gas and a reactive gas into the processing space V of the chamber 100 , And an ITO film is formed on the substrate 91 facing the target 16.

<1.3 Film Deposition Treatment>

In the film forming process, first, the sputter gas supplying section 510 supplies a sputter gas such as argon gas, which is an inert gas, to the processing space V (sputter gas supplying step).

Also, the reactive gas supply unit 520 supplies reactive gas such as oxygen gas to the processing space V (reactive gas supply step). As a result, a mixed atmosphere of the sputter gas and the reactive gas is formed in the processing space (V).

Each rotary section 19 rotates the rotary cathodes 5 and 6 around the respective central axes 2 and 3 by the rotation of the motor (rotation step). More specifically, the rotating portion 19 is disposed so that the portions of the outer circumferential surfaces of the rotating cathodes 5 and 6 facing each other are moved from the side of the inductively coupled antenna 151 toward the side of the substrate 91, 2, 3) of the rotating cathode 5, 6 in the opposite direction to each other.

The sputter power source 163 supplies sputter power of 1.5 kW / m or less to the rotating cathodes 5 and 6 (sputter power supply step). This sputter power is, for example, 0.6 kW / m. Here, kW / m is a unit of the sputtering power in the rotating cathodes 5 and 6 and means the number of watts to be applied per 1 meter in the axial direction of the target 16 wound around the outer periphery of the rotating cathodes 5 and 6 do. Sputter power is supplied to the rotating cathodes 5 and 6, thereby generating a magnetron plasma.

The high frequency power supply 153 supplies the high frequency power to each of the inductively coupled antennas 151 (high frequency power supply step). This high frequency power is, for example, a power of 13.56 MHz in frequency. Thereby, an inductively coupled plasma is generated. A mixed plasma of the magnetron plasma and the inductively coupled plasma is formed between the rotating cathodes 5 and 6 and in the space on the side of the film formation point P side.

The transport mechanism 30 transports the substrate 91 along the transport path surface L (transport step). More specifically, the transport mechanism 30 moves the substrate 91 along the transport path surface L in the ± X direction so that the substrate 91 passes through the film formation point P a plurality of times.

The heating section 40 heats the substrate 91 to be conveyed (heating step). The heating section 40 heats the base material 91, for example, at 300 占 폚. When the heating temperature of the substrate 91 is 200 DEG C or more, the ITO film is crystallized with a low resistivity relative to the substrate 91. [

As a result, ITO particles sputtered from the target 16 of the rotating cathodes 5 and 6 are crystallized and deposited on the main surface on the -Z side of the conveyed substrate 91, and an ITO film is formed. This ITO film is used, for example, as an anode of an organic EL device.

<1.4 Resistivity and flatness of ITO film>

5 is a graph showing the relationship between the sputtering power and the resistivity of the resulting ITO film. &Quot; Planar DC-Bias power &quot; which is the horizontal axis on the upper side of the city represents the DC sputter power value applied to the magnetron cathode of the planer type. &Quot; Rotary DC-Bias power &quot;, which is the horizontal axis of the lower side of the figure, represents the DC sputter power value applied to the magnetron cathode pair of the rotary type. The "Bottom Resistivity", which is the vertical axis in the figure, represents the lowest resistivity of the ITO film obtained by the film forming process.

The white square in the figure is a plot of the resistivity in the case where the magnetron cathode is a planer cathode and the LIA does not support sputtering. The black square in the figure is a plot of the resistivity when the magnetron cathode is a planer cathode and the LIA supports sputter processing. A white circle in the drawing is a plot of the resistivity when the magnetron cathode pair is of a rotary type and the LIA does not support sputtering. The black circle display in the drawing is a plot of the resistivity when the magnetron cathode pair is a rotary type and the LIA supports sputter processing. Here, "LIA supports sputter processing" means that inductively coupled plasma by the LIA contributes to the sputter processing by the magnetron cathode pair as in the present embodiment.

5, the deposition rate of the ITO film at the sputtering power of 2.0 W / cm &lt; 2 &gt; for the spinner type magnetron cathode and the sputtering power for the rotary-type magnetron cathode pair were 1.4 kW / m, the deposition rate of the ITO film was substantially the same. For this reason, in FIG. 5, the abscissa of the sputtering power of 2.0 W / cm 2 and the abscissa of the sputtering power of 1.4 kW / m have substantially the same positional relationship.

As can be seen by comparing the square display and the circle display in Fig. 5, when the film forming speed is made approximately the same, the ITO film formed by the magnetron pair of the rotary type is formed by the magnetron cathode of the planer type The resistivity becomes lower than that of the ITO film. In the rotary-type magnetron cathode pair, the magnetron plasma becomes higher in density as compared with the magnetron cathode of the planer type, and the effect of the ITO target proceeds more uniformly. As a result, in the rotary-type magnetron cathode pair, activation of Sn ions is promoted (doping efficiency of Sn is increased) on the film formation surface in the film forming process as compared with the magnetron cathode pairs of the planar type, It does not happen very well. The higher doping efficiency of Sn leads to a lowering of the resistivity of the ITO film. The presence of nodules causes the resistivity of the ITO film to be deposited to increase. Therefore, by using a magnetron cathode pair of a rotary type, an ITO film having a low resistivity is stably formed. In addition, since the presence of the nodule causes arcing, the use of a rotary-type magnetron cathode pair suppresses the generation of particles in the ITO film due to arcing.

In this embodiment, since a rotary-type magnetron cathode pair including the rotating cathodes 5 and 6 is used, it is preferable that an ITO film having a lower resistivity and a low number of particles can be stably formed.

5, when the sputtering power is in the range of 0.8 to 3.0 kW / m, the resistivity is lowered as the sputtering power is lowered, and the sputtering power is 0.5 to 0.8 kW / m, the sputtering power becomes almost constant. Therefore, with respect to the resistivity of the ITO film, the smaller the sputtering power is in the range of 0.8 to 3.0 kW / m, the better, and the sputtering power is preferably in the range of 0.5 to 0.8 kW / m.

Although not shown in Fig. 5, if the sputtering power is less than 0.5, the proportion of the impurities in the ITO film to be formed due to the lowering of the film formation rate is increased, and the activation rate of Sn ions is lowered The resistivity of the ITO film is increased. Therefore, in terms of the deposition rate and resistivity of the ITO film, the sputtering power is preferably 0.5 kW / m or more.

The low resistivity required for the ITO film differs depending on the product using the ITO film, but it is preferable that the resistivity required for the ITO film is 120 占 cm (micro-ohm centimeter) or less. Therefore, as can be seen from Fig. 5, when the sputtering power is 2.1 kW / m or less, the resistivity of the ITO film is preferable to be a low resistivity of 120 占 cm or less.

In the present embodiment, the LIA supports the sputter processing, and the sputter power supplied to the rotary-type magnetron cathode pair is 0.6 kW / m. Therefore, in the present embodiment, an ITO film having a sufficiently low resistivity can be formed, which is preferable.

FIG. 6 is a graph showing the relationship between the amount of sputtering in the case where five kinds of sputter power are supplied in the embodiment in which the LIA supports sputter processing and the case where five kinds of sputter power are supplied in the embodiment in which the LIA does not support the sputter processing. And the film surface is enlarged and shown. 6 shows the resistivity (Res.), The average roughness (Ra), and the maximum roughness (Rmax) for a total of ten cases. The average roughness and the maximum roughness will be described later in detail with reference to FIG.

7 is a graph showing the relationship between the deposition thickness of the ITO film and the carrier density, the relationship between the deposition thickness and the hole mobility of the ITO film, and the deposition thickness and resistivity of the ITO film. The &quot; Deposition thickness &quot; which is the abscissa in the figure indicates the deposition thickness of the ITO film. The &quot; Carrier density &quot;, which is the vertical axis on the right side of the city, indicates the carrier density of the ITO film. &Quot; Hall Mobility &quot;, which is the vertical axis on the left side of the figure, represents the hole mobility of the ITO film. "Resistivity", which is the vertical axis on the left side of the figure, represents the resistivity of the ITO film.

The white rectangular display in the figure is a plot of the carrier density when the LIA does not support sputter processing. The black rectangular display in the drawing is a plot of the carrier density when the LIA supports the sputter processing. The white circle display in the drawing is a plot of hole mobility when the LIA does not support the sputter processing. The black circle display in the drawing is a plot of hole mobility when the LIA supports the sputter processing. The white triangle in the figure is a plot of the resistivity when the LIA does not support sputtering. The black triangle in the drawing is a plot of the resistivity when the LIA supports sputter processing.

As can be seen by comparing the white square display and the black square display in Fig. 7, the carrier density of the ITO film in the case where the LIA supports the sputter processing is the same as that in the case where the LIA does not support the sputter processing Is larger than the carrier density of the ITO film.

As can be seen by comparing the white circle display and the black circle display in Fig. 7, the hole mobility of the ITO film in the case where the LIA supports the sputter processing is determined in the case where the LIA does not support the sputter processing Is approximately the same as the hole mobility of the ITO film. Strictly speaking, the hole mobility of the ITO film when the LIA supports the sputter processing is slightly smaller than the hole mobility of the ITO film when the LIA does not support the sputter processing.

Since the product of the carrier density and the hole mobility is inversely proportional to the resistivity, as can be seen by comparing the white triangle and the black triangle in Fig. 7, the resistivity of the ITO film in the case where the LIA supports the sputtering process, Is lower than the resistivity of the ITO film when the sputtering process is not supported. When the black square display and the white square display in Fig. 5 are compared with each other and the black circle display and the white circle display in Fig. 5 are compared with each other, the LIA supports the sputter processing so that the resistivity of the ITO film It can be seen that the effect is lowered.

In the present embodiment, since the inductively coupled antenna 151 (LIA) supports sputter processing, it is possible to form an ITO film with a lower resistivity, which is preferable.

8 is a graph showing the relationship between the DC sputter power supplied to the magnetron cathode pair of the rotary type and the flatness of the ITO film surface within 5 mu m. The "DC-Bias power", which is the horizontal axis in the figure, represents the DC sputter power supplied to the magnetron cathode pair of the rotary type. "R max", which is the vertical axis on the right side of the city, is the maximum illuminance of the surface of the ITO film, and represents the height difference between the highest position (mountain) and the lowest position (bone) in the thickness direction of the ITO film surface. The vertical axis "Ra" on the left side of the figure indicates the average roughness of the surface of the ITO film and the average value of the deviation from the reference height with respect to the thickness direction of the ITO film surface. The smaller the maximum roughness and the average roughness, the higher the flatness of the ITO film. That is, in the present specification, "the flatness of the ITO film is high" means that the maximum illuminance and the average illuminance of the ITO film are small, and "the flatness of the ITO film is low" means that the maximum illuminance and average illuminance of the ITO film are large .

The white square display in the figure is a plot of the maximum illuminance in the mode in which the LIA does not support sputter processing. The black square in the drawing is a plot of the maximum roughness in the mode in which the LIA supports sputter processing. The white circled display in the figure is a plot of the average roughness in the mode in which the LIA does not support sputter processing. The black circle display in the drawing is a plot of the average roughness in the mode in which the LIA supports the sputter processing.

As can be seen by comparing the white square display and the black square display in Fig. 8, when the sputter power is larger than 1.5 kW / m, the maximum illuminance of the ITO film in the mode in which the LIA supports the sputter processing is larger than the LIA Is larger than the maximum illuminance of the ITO film in the mode in which the sputter processing is not supported. On the other hand, when the sputter power is 1.5 kW / m or less, the maximum illuminance of the ITO film in the mode in which the LIA supports the sputter processing is smaller than the maximum illuminance of the ITO film in the mode in which the LIA does not support the sputter processing.

As can be seen by comparing the white circle display and the black circle display in Fig. 8, when the sputter power is larger than 1.5 kW / m, the average illuminance of the ITO film in the mode in which the LIA supports the sputter processing is larger than the LIA Is larger than the average roughness of the ITO film in the mode in which the sputter processing is not supported. On the other hand, when the sputter power is 1.5 kW / m or less, the average roughness of the ITO film in the mode in which the LIA supports the sputter process is smaller than the average roughness of the ITO film in the mode in which the LIA does not support the sputter process.

Thus, in the case where the sputter power supplied to the rotary-type magnetron cathode pair is 1.5 kW / m or less, the flatness of the ITO film to be formed in the mode in which the LIA supports the sputter processing is such that the LIA does not support the sputter processing, Which is higher than the flatness of the ITO film. Therefore, it is preferable that the sputtering power is 1.5 kW / m or less.

The high level of flatness required for the ITO film differs depending on the product using the ITO film, but it is preferable that the average roughness required for the ITO film is 1.5 nm (nanometer) or less, for example. Therefore, as can be seen from Fig. 8, when the sputtering power is 1.3 kW / m or less, the average roughness of the ITO film becomes high flatness of 1.5 nm or less, which is preferable.

In the present embodiment, the LIA supports the sputter processing, and the sputter power supplied to the rotary-type magnetron cathode pair is 0.6 kW / m. For this reason, in the present embodiment, it is preferable to form an ITO film having a sufficiently small maximum roughness and a small average roughness (that is, a sufficiently high flatness).

9 is a graph showing the relationship between the heating temperature of the substrate 91 by the heating section 40 and the flatness of the surface of the ITO film in the case of performing the film forming process of the ITO film by using a rotary type magnetron cathode pair to be. The horizontal axis "Substrate depo.Temp" in the figure indicates the temperature of the substrate 91 on which the ITO film is formed. "R max", which is the vertical axis on the right side of the city, is the maximum illuminance of the surface of the ITO film, and represents the height difference between the highest position (mountain) and the lowest position (bone) in the thickness direction of the ITO film surface. The vertical axis "Ra" on the left side of the figure indicates the average roughness of the surface of the ITO film and the average value of the deviation from the reference height with respect to the thickness direction of the ITO film surface.

The black square in the drawing is a plot of the maximum roughness in the mode in which the LIA supports sputter processing. The black circle display in the drawing is a plot of the average roughness in the mode in which the LIA supports the sputter processing.

As can be seen from the transition of the black square display in Fig. 9, the maximum illuminance decreases as the temperature increases in the range of 230 to 300 deg. C, and the maximum illuminance decreases in the range of 300 to 330 deg. Is almost constant. Therefore, with respect to the maximum roughness of the surface of the ITO film, the higher the temperature is, the better the temperature is in the range of 230 to 300 캜, and the more preferably the temperature is in the range of 300 to 330 캜.

In this embodiment, a rotary type magnetron cathode pair is used, the LIA supports sputter processing, and the heating temperature of the substrate 91 by the heating part 40 is 300 占 폚. For this reason, in the present embodiment, it is preferable to form an ITO film having a sufficiently low maximum roughness.

&Lt; 2 &lt; Second Embodiment &gt;

<2.1 Overall Configuration of Sputtering Device 1A>

10 is a schematic cross-sectional view showing a configuration example of the sputtering apparatus 1A according to the second embodiment. Hereinafter, the sputtering apparatus 1A of the second embodiment will be described, but the same elements as those of the sputtering apparatus 1 of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

The sputtering apparatus 1A according to the second embodiment is different from the sputtering apparatus 1 according to the first embodiment in that the sputtering apparatus 1A according to the second embodiment further includes a water vapor supply unit 530 for supplying water vapor to the processing space V, (Oxygen concentration in the present embodiment) and the concentration of water vapor (moisture concentration) in the reaction gas (reaction gas). The sputtering apparatus 1A includes a control unit 190A capable of communicating with each part of the sputtering apparatus 1A including the steam supply unit 530 and the measurement unit 18 in place of the control unit 190 of the sputtering apparatus 1. [ . Hereinafter, the difference between the sputtering apparatus 1 and the sputtering apparatus 1A will be mainly described.

The water vapor supply unit 530 includes, for example, a water vapor supply source 531 serving as a supply source of water vapor and a pipe 532. One end of the pipe 532 is connected to the water vapor source 531 and the other end is connected to the pipe 522 of the reactive gas supply unit 520. A valve 533 is formed in the middle of the path of the pipe 532. The valve 533 adjusts the amount of water vapor supplied to the processing space V under the control of the control unit 190A. The valve 533 is preferably a valve capable of automatically regulating the flow rate of the gas flowing through the piping. Specifically, the valve 533 is preferably configured to include, for example, a mass flow controller.

The water vapor supplied from the water vapor supply source 531 and the reactive gas supplied from the reactive gas supply source 521 are merged in the pipe and discharged from the plurality of nozzles 12 into the processing space V. [ Thus, the water vapor and the reactive gas are discharged into the processing space V through the common path, so that the distribution of the water vapor and the reactive gas in the processing space V becomes more uniform.

The measuring section 18 is constituted by a quadrupole mass spectrometer and it is possible to measure the total pressure of the gas in the processing space V and the partial pressure of each gas. Therefore, the measuring section 18 has a function as a first measuring section for measuring the concentration of the reactive gas in the processing space V by measuring the total pressure in the processing space V and the partial pressure of the reactive gas, And has a function as a second measuring section for measuring the concentration of water vapor in the processing space V by measuring the total pressure in the space V and the partial pressure of water vapor. Here, the concentration of the gas is represented by the partial pressure ratio of the gas to the total pressure in the processing space (V).

The control unit 190A performs feedback control of the valve 523 of the reactive gas supply unit 520 on the basis of the measurement result of the measuring unit 18 so that the concentration of the reactive gas during the sputtering film formation is the first target value set in advance. The control unit 190A performs feedback control of the valve 533 of the water vapor supply unit 530 based on the measurement result of the measurement unit 18 so that the concentration of the water vapor during the sputter deposition becomes the second target value set in advance.

During the sputtering film forming period, the measuring section 18 performs the measurement a plurality of times at regular intervals (for example, at intervals of 4 seconds), and whenever the measurement result from the measuring section 18 is obtained, And supplies a control signal to the gas supply unit 520 and the steam supply unit 530. Thus, the feedback control described above is realized.

&Lt; 2.2 Process in Sputtering Apparatus 1A &

11 is a graph showing the relationship between the resistivity of the ITO film and the flatness of the ITO film surface measured by the measuring section 18 in the processing space (V) when the film forming process of the ITO film is performed using the magnetron- And the concentration of each gas. Also the horizontal axis is "O ₂ / Total pressure" in 11 shows a ratio of the pressure of the reactive gas (oxygen) for the total pressure in the processing space (V) in percentage display. The vertical axis "Ra" in the center of the right side of the center is the average roughness of the surface of the ITO film to be formed, and represents the average value of the displacement of the surface of the ITO film viewed from the reference height with respect to the thickness direction. The vertical axis "R max" on the upper right of the city indicates the highest illuminance of the surface of the ITO film to be formed and the highest position (mountain) and the lowest position (trough) of the ITO film surface in the thickness direction. Resistivity, which is the vertical axis on the left side of the figure, indicates the resistivity of the ITO film to be formed.

11 shows that the substrate 91 is heated to 280 占 폚, RF power of 1.6 kW is supplied to the LIA, sputter power of 0.6 kW / m is supplied to the pair of magnetron cathodes, and the total pressure in the processing space (V) 0.5 Pa. &Lt; tb &gt; &lt; TABLE &gt; The white triangle in the figure is a plot of resistivity when the concentration of water vapor is 0.3%. A black triangle in the drawing is a plot of resistivity when the concentration of water vapor is 1.0%. The white circles in the drawing are plots of the average roughness when the concentration of water vapor is 0.3%. The black circles in the figure are plots of the average roughness when the concentration of water vapor is 1.0%. The white square in the figure is a plot of the maximum illuminance when the concentration of water vapor is 0.3%. The black rectangular display in the drawing is a plot of the maximum illuminance when the concentration of water vapor is 1.0%.

Hereinafter, the processing in the sputtering apparatus 1A will be described with reference to Figs. 10 and 11. Fig.

In the processing in the sputtering apparatus 1A, a preparation step (a first step and a second step described later) for setting the first target value and the second target value is performed first.

In the first step, the concentration of the water vapor is 0.3%, and the concentration of the reactive gas is different (for example, the concentration of the oxygen gas is 0.15%, 0.19%, 0.23%, 0.25%, 0.29% (Under the conditions of the five concentrations of the sputtering apparatus 1A). By examining the resistivity and the flatness of the ITO film thus obtained, each plot of the white triangle display, each plot of the white circle display, and each plot of the white square display in FIG. 11 is obtained.

The concentration of the reactive gas when the resistivity of the deposited ITO film becomes smaller than the first threshold value is set as the first target value based on the result of the film formation. At this time, a threshold value (for example, a resistivity of 100 [micro-ohm cm]) required for the final product is used as the first threshold value and the first target value is set as the resistivity of the ITO film. Therefore, by passing through this first step, the reduction of the resistivity of the ITO film is realized.

Hereinafter, the case where the concentration of the reactive gas (0.19%) when the resistivity of the ITO film is the smallest in each deposition result in the first step is set as the first target value will be described. In the embodiment in which the first target value is set by minimizing the resistivity as described above, the lowering of the resistivity of the ITO film is realized.

Next, the second step of the preparation step is executed. In the second step, under the condition that the concentration of the reactive gas is set to the first target value (0.19%) and the concentration of the steam is different (for example, the concentration of the water vapor is 0.5%, 1.0%, 1.5% Sputtering is performed by the sputtering apparatus 1A under the conditions of three concentrations.

Based on the result of the film formation, the concentration of the water vapor when the flatness of the ITO film formed when the concentration of the reactive gas is the first target value (0.19%) becomes higher than the second threshold value is set as the second target value (1.0%) Setting. At this time, as the flatness of the ITO film, the threshold value (for example, the maximum roughness Rmax = 15 [nm] and the average roughness Ra = 1.5 [nm]) required for the final product is used as the second threshold value, Is set. Therefore, by passing through this second step, the ITO film becomes a high flatness trajectory. 11, the concentration of the reactive gas among the respective concentrations of water vapor formed in the second step (for example, three concentrations of water vapor concentrations of 0.5%, 1.0%, and 1.5%) is the first target value %) And the concentration of water vapor is the second target value (1.0%). 11 shows the reference plot for explaining the effect described later. In addition to the respective plots obtained in the first and second steps, the concentration of the reactive gas is 0.11% and the concentration of the water vapor is the second target value (1.0% ) And each plot when the concentration of the reactive gas is 0.27% and the concentration of water vapor is the second target value (1.0%).

Hereinafter, the concentration of water vapor (1.0%) when the flatness of the ITO film becomes the highest (in other words, the maximum roughness Rmax and the average roughness Ra are the smallest) 2 &quot; target value &quot; In this embodiment in which the second target value is set by maximizing the flatness, the ITO film has a higher trajectory.

<2.3 Deposition process>

When the preparation process is completed, film formation is sequentially performed on the plurality of substrates 91 to be transported.

In the film forming process, first, the sputter gas supplying section 510 supplies a sputter gas such as argon gas, which is an inert gas, to the processing space V (sputter gas supplying step). Also, the reactive gas supply unit 520 supplies reactive gas such as oxygen gas to the processing space V (reactive gas supply step). In addition, the water vapor supply part 530 supplies water vapor to the processing space V (water vapor supply step). Thus, a mixed atmosphere of the sputter gas, the reactive gas, and the water vapor is formed in the processing space (V).

Each rotary section 19 rotates the rotary cathodes 5 and 6 around the respective central axes 2 and 3 by the rotation of the motor (rotation step). More specifically, the rotating portion 19 is disposed so that the portions of the outer circumferential surfaces of the rotating cathodes 5 and 6 facing each other are moved from the side of the inductively coupled antenna 151 toward the side of the substrate 91, 2, 3) of the rotating cathode 5, 6 in the opposite direction to each other.

The sputter power source 163 supplies sputter power of 1.5 kW / m or less to the rotating cathodes 5 and 6 (sputter power supply step). This sputter power is, for example, 0.6 kW / m. Sputter power is supplied to the rotating cathodes 5 and 6, thereby generating a magnetron plasma.

The high frequency power supply 153 supplies the high frequency power to each of the inductively coupled antennas 151 (high frequency power supply step). This high frequency power is, for example, a power of 13.56 MHz in frequency. Thereby, an inductively coupled plasma is generated. A mixed plasma of the magnetron plasma and the inductively coupled plasma is formed between the rotating cathodes 5 and 6 and in the space on the side of the film formation point P side.

The transport mechanism 30 transports the substrate 91 along the transport path surface L (transport step). More specifically, the transport mechanism 30 moves the substrate 91 along the transport path surface L in the ± X direction so that the substrate 91 passes through the film formation point P a plurality of times.

The heating section 40 heats the substrate 91 to be conveyed (heating step). The heating section 40 heats the base material 91, for example, at 280 占 폚. When the heating temperature of the substrate 91 is 200 DEG C or more, the ITO film is crystallized with a low resistivity relative to the substrate 91. [

During the film forming process, the measuring section 18 measures the concentration of the reactive gas in the process space V a plurality of times at a constant cycle (first measurement process), and further, in the process space V Is measured a plurality of times at a constant cycle (second measurement step). In the above-described reactive gas supply step, the supply of the reactive gas is feedback-controlled based on the measurement result by the measuring unit 18 so that the concentration of the reactive gas during the sputtering is the first target value set in advance. In addition, in the above-described steam supplying step, the supply of the steam is feedback-controlled based on the measurement result by the measuring part 18 so that the concentration of the water vapor during the sputtering is a second target value set in advance.

<2.4 Resistivity and flatness of ITO film>

Hereinafter, from the viewpoint of the resistivity and flatness of the ITO film, the effect of the sputtering apparatus 1A of the second embodiment will be described.

As described in the first embodiment, by supplying sputter power of 1.5 kW / m or less (in this embodiment, 0.6 kW / m) to the rotary-type magnetron cathode pair and performing sputtering under LIA support, The low resistivity and high flatness of the ITO film can be realized.

As can be seen from Fig. 11, in the second embodiment, by adjusting the concentration of oxygen and the concentration of water vapor, a low resistivity and high flatness of the ITO film are realized. Hereinafter, this point will be described in detail.

As shown by the six curves in Fig. 11 (two curves for resistivity, two curves for average roughness, and two curves for maximum roughness), under the conditions of this embodiment, The curves of the ITO film having the abscissa and the resistivity, the average roughness and the maximum roughness as the ordinate are convex curves having the minimum values ". Here, the conditions in this embodiment refer to a condition in which sputtering power of 1.5 kW / m or less (specifically, 0.6 kW / m 2) is supplied to a rotary-type magnetron cathode pair and ITO sputtering is performed under LIA support .

When the concentration of water vapor is changed under this condition, the minimum value of the resistivity and the concentration of the corresponding reactive gas are sufficiently small, while the minimum value of the average roughness and the corresponding concentration of the reactive gas and the maximum roughness And the concentration of the corresponding reactive gas has a large amount of change &quot;.

Further, even when the concentration of water vapor is changed under this condition, the curves of the curve relating to the average roughness and the curve relating to the maximum roughness are similar, and the minimum value of the curves and the corresponding concentration of the reactive gas are almost the same The third knowledge was obtained.

According to the above-described findings, in the preparation step of the second embodiment, the first step of firstly setting the concentration of the reactive gas when the resistivity of the ITO film formed becomes smaller than the first threshold value, Then, the second step of setting the concentration of the water vapor when the flatness of the ITO film formed becomes higher than the second threshold value is set as the second target value.

In the first step, since the concentration of the reactive gas is determined from the viewpoint of lowering the resistivity of the ITO film, the lowering of the resistivity of the ITO film can be realized. At this time, when the first target value that minimizes the resistivity of the ITO film is set according to the first knowledge, the lowering of the resistivity of the ITO film can be further realized. In the second step, since the concentration of water vapor is determined from the viewpoint of increasing the flatness of the ITO film, the high flatness of the ITO film can be realized from the above third knowledge. At this time, when the second target value that minimizes the average roughness and the maximum roughness of the ITO film is set according to the first knowledge, the high flatness of the ITO film can be realized more. Although the concentration of water vapor, which is different from that of the first step, is set to the second target value by the second step, from the second knowledge, the inhibition of the lowering of the resistivity of the ITO film is suppressed.

In the present embodiment, the supply amount of the gas is feedback-controlled based on the measured value (the partial pressure ratio of gas) obtained within the processing space V by the measuring unit 18. [ Therefore, in the embodiment of the present embodiment, compared with other embodiments in which the supply amount of gas is feedback-controlled based on the measured value obtained by the gas supply amount by, for example, the mass flow controller, the actual processing in the processing space Precision feedback control conforming to the conditions can be performed.

&Lt; 3 Modified Example &

Although the embodiment of the present invention has been described above, the present invention can be modified in various ways other than the above-described one as long as it does not deviate from the purpose.

In the above embodiment, the film forming process is performed on the substrate 91 conveyed above one plasma processing unit 50 formed in one chimney 60, but the present invention is not limited thereto. The substrate 91 transported above the plurality of plasma processing sections 50 formed in the plurality of chimneys 60 may be subjected to the film forming process.

In the above-described embodiment, the film forming process is performed on the base material 91 transported in the horizontal direction. However, the present invention is not limited to this. For example, And the conveying direction of the substrate 91 can be appropriately selected.

The respective processing conditions (the sputter power value supplied to the pair of magnetron cathodes, the heating temperature of the substrate 91, etc.) in the above embodiment can be appropriately changed within the scope of the present invention.

In the second embodiment, the case where the concentration of the water vapor in the first step is performed at one value (0.3%) has been described, but the present invention is not limited thereto. The concentration of water vapor in the first step may be a different value or a plurality of values.

In the second embodiment, the case where the measuring section 18 is constituted by a quadrupole mass spectrometer has been described, but the present invention is not limited thereto. The measuring section 18 may have another configuration (for example, a configuration using the PEM method) as long as the configuration can measure the gas concentration in the processing space. In the second embodiment, the case where the partial pressure ratio of the gas to the total pressure in the processing space V is used as the concentration of the gas has been described. However, an approximate value of this value may be used as the concentration of the gas. For example, when the concentration of water vapor is measured by the PEM method, the partial pressure ratio of the hydrogen gas to the argon partial pressure in the processing space V is used as the concentration of the water vapor.

In the second embodiment, the measurement section 18 (quadrupole mass spectrometer) measures the total pressure and the partial pressure of each gas, and functions as a first measuring section for measuring the concentration of the reactive gas and a concentration of water vapor And a function as the second measuring unit has been described, the present invention is not limited to this. For example, the measuring part for measuring the total pressure of the gas, the measuring part for measuring the partial pressure of the reactive gas, and the measuring part for measuring the partial pressure of the water vapor may be separately formed.

In the second embodiment, the measuring section 18 (quadrupole mass spectrometer) is connected below the processing space V, and the measuring section 18 measures the concentration of the reactive gas in the processing space V, The description has been made on the mode in which the concentration of water vapor can be measured, but the present invention is not limited thereto. In general, the ratio of the gas inside and outside the processing space V in the chamber 100 is measurable and reproducible. Therefore, the measuring unit 18 measures the concentration of the reactive gas in the chamber 100 and the concentration of the water vapor Is sufficient. The measuring section 18 is connected to the inside of the chamber 100 outside the process space V (outside the chamber 60) and the chamber 100 is connected to the inside of the chamber 100 by the measuring section 18, The concentration of the reactive gas and the concentration of the water vapor in the reaction gas.

In the second embodiment, the case where the measuring section 18 is constituted by a quadrupole mass spectrometer has been described, but the present invention is not limited thereto. The measurement section 18 may have another configuration (for example, a configuration using the PEM method) as long as it can measure a value reflecting the gas concentration or the gas concentration in the processing space.

In the second embodiment, the description has been given of the aspect in which the water vapor supplied from the water vapor source 531 and the reactive gas supplied from the reactive gas supply source 521 are combined in the pipe and discharged to the processing space V, But is not limited thereto. The steam supplied from the steam supply source 531 and the sputter gas supplied from the sputter gas supply source 511 may be combined in the piping and discharged to the processing space V. The steam, the reactive gas, and the sputter gas Or may be fed in different routes and discharged to the processing space V, respectively.

The sputtering apparatus and the sputtering method according to the embodiment and its modified examples have been described above. However, the embodiments are not intended to limit the scope of the present invention. The present invention can be freely combined with each embodiment, or a modification of any component of each embodiment within the scope of the invention, or an arbitrary component in the embodiment can be increased or decreased.

1, 1A: sputtering device
50: Plasma processing section
100: chamber
151: Inductively Coupled Antenna
153: High frequency power source
163: Power source for sputtering
30:
31: conveying roller
5, 6: Rotating cathode
7: Support rod
8: Base member
16: Target
19:
21, 22: magnet unit
60: Chimney
90: Carrier
91: substrate
510: Sputter gas supply unit
520: Reactive gas supply unit
530: Water vapor supply unit
18:
V: processing space

Claims (18)

A sputtering apparatus for forming an ITO (Indium Tin Oxide) film on a main surface of a substrate to be transported by sputtering,
A vacuum chamber in which a processing space is formed,
A sputter gas supply unit for supplying a sputter gas to the processing space;
A reactive gas supply unit for supplying a reactive gas to the process space;
At least one plasma processing section for performing plasma processing in the processing space,
And a transport mechanism for transporting the substrate along a transport path surface including at least one film formation point opposed to the at least one plasma processing section,
Wherein each of the at least one plasma processing units comprises:
A cathode pair in which two rotating cathodes whose circumferential surfaces are coated with a target material containing indium (In), tin (Sn), and oxygen (O) are disposed opposite to each other with a certain distance in the processing space ,
A rotating portion for rotating the two rotating cathodes around respective central axes,
Sputter power supply means for supplying sputter power of 1.5 kW / m or less to each of the two rotating cathodes,
Two magnetic field generating units each accommodated in the two rotating cathodes and forming a magnetic field in the vicinity of the outer peripheral surface,
At least one LIA (Low Inductance Antenna) generating an inductively coupled plasma in a space of the processing space including a portion where the magnetic field is formed,
And a high-frequency power supply means for supplying high-frequency power to the at least one LIA. The method according to claim 1,
Wherein the sputter power supply means supplies sputter power of 1.0 kW / m or less to the two rotating cathodes. 3. The method of claim 2,
Wherein the sputter power supply means supplies sputter power of 0.5 kW / m or more to the two rotating cathodes. The method according to claim 1,
Further comprising a heating portion for heating the substrate to 200 DEG C or higher. The method according to claim 1,
Wherein the ITO film is used as an anode of an organic EL device. 6. The method according to any one of claims 1 to 5,
A first measurement unit for measuring a concentration of the reactive gas in the vacuum chamber,
A water vapor supply unit for supplying water vapor to the processing space,
A second measurement unit for measuring the concentration of the water vapor in the vacuum chamber,
Feedback control of the reactive gas supply unit based on the result of measurement by the first measurement unit such that the concentration of the reactive gas during the sputter deposition is a first target value set in advance, And a control unit for feedback-controlling the steam supply unit based on the measurement result of the second measurement unit so as to satisfy the two target values. The method according to claim 6,
A first step of setting, as the first target value, the concentration of the reactive gas when the resistivity of the deposited ITO film becomes smaller than the first threshold, based on each deposition result performed under the conditions where the concentration of the reactive gas is different;
Based on the result of each film formation performed under the condition that the concentration of the reactive gas is different from that of the reactive gas under the feedback control under the first target value, And a second step of setting the concentration as the second target value is carried out. 8. The method of claim 7,
Wherein the first target value is the concentration of the reactive gas when the resistivity of the ITO film is the smallest in the film forming results of the first step. 8. The method of claim 7,
Wherein the second target value is the concentration of the water vapor when the flatness of the ITO film becomes the highest in the film forming results of the second step. An ITO (Indium Tin Oxide) film is formed on the main surface of the substrate to be transferred by using a device including a vacuum chamber for forming a processing space therein and at least one plasma processing section for performing plasma processing in the processing space, As the sputtering method,
Wherein each of the at least one plasma processing unit is configured such that two rotating cathodes which are cylindrical and whose outer circumferential surfaces are coated with a target material containing indium (In), tin (Sn), and oxygen (O) And a magnetic field generating unit for generating a magnetic field in the vicinity of the outer circumferential surface of the cathode pair, the inductively coupled plasma generating unit generating a inductively coupled plasma in a space including a portion of the processing space where the magnetic field is formed At least one LIA (Low Inductance Antenna)
The method comprises:
A sputter gas supplying step of supplying a sputter gas to the processing space;
A reactive gas supplying step of supplying a reactive gas to the processing space;
A rotating step of rotating each rotating cathode around each central axis;
A sputter power supply step of supplying sputter power of 1.5 kW / m or less to each of the rotating cathodes,
A high frequency power supply step of supplying a high frequency power to the at least one LIA;
And a transporting step of transporting the substrate along a transport path surface including at least one film formation point opposed to the at least one plasma processing section. 11. The method of claim 10,
Wherein the sputtering power supply step supplies sputter power of 1.0 kW / m or less to each of the rotating cathodes. 12. The method of claim 11,
Wherein the sputter power supplying step supplies sputter power of 0.5 kW / m or more to each of the rotating cathodes. 11. The method of claim 10,
Further comprising a heating step of heating the substrate to 200 DEG C or higher. 11. The method of claim 10,
Wherein the ITO film is used as an anode of an organic EL device. 15. The method according to any one of claims 10 to 14,
A first measuring step of measuring a concentration of the reactive gas in the vacuum chamber,
A water vapor supplying step of supplying water vapor to the processing space,
And a second measuring step of measuring the concentration of the water vapor in the vacuum chamber,
In the reactive gas supplying step, the supply of the reactive gas is feedback-controlled based on the measurement result of the first measuring unit so that the concentration of the reactive gas during the sputtering is a first predetermined target value,
Wherein the supply of the water vapor is feedback-controlled based on a measurement result of the second measurement unit so that the concentration of the water vapor during the sputter deposition is a second target value in the water vapor supply step. 16. The method of claim 15,
A preparation step of setting the first target value and the second target value,
A first step of setting, as the first target value, the concentration of the reactive gas when the resistivity of the deposited ITO film becomes smaller than the first threshold, based on each deposition result performed under the conditions where the concentration of the reactive gas is different;
Based on the result of each film formation performed under the condition that the concentration of the reactive gas is different from that of the reactive gas under the feedback control under the first target value, And setting a concentration as the second target value. 17. The method of claim 16,
Wherein the first target value is a concentration of the reactive gas when the resistivity of the ITO film is the smallest in each film forming result of the first step. 17. The method of claim 16,
Wherein the second target value is the concentration of the water vapor when the flatness of the ITO film becomes the highest in the film forming results of the second step.

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