JP7201448B2 - Plasma processing apparatus and plasma processing method - Google Patents

Description

The present application relates to a plasma processing apparatus and a plasma processing method.

Patent Document 1 discloses an inductively coupled plasma CVD (Plasma-enhanced Chemical Vapor Deposition) apparatus. This plasma CVD apparatus is an apparatus for forming a thin film on a substrate. This plasma CVD apparatus includes a chamber, a holding/transporting section, an inductively coupled antenna, and a gas introducing section. The holding and transporting part holds the substrate substantially horizontally in the chamber and transports the substrate along the substantially horizontal transport path. The gas introduction part introduces gas into the chamber. As the gas, for example, a raw material gas such as silane (SiH ₄ ) and an additive gas such as argon (Ar) can be used. The inductively coupled antenna is arranged above the conveying route in the middle of the conveying route. When a high-frequency current flows through an inductively coupled antenna, plasma (inductively coupled plasma) is generated around the inductively coupled antenna.

In such a plasma CVD apparatus, the holding/conveying unit conveys the substrate along the conveying path so that the substrate moves directly below the inductively coupled antenna. Since plasma is generated around the inductive coupling antenna, the plasma acts on the surface of the substrate when the substrate moves directly under the inductive coupling antenna. Thereby, a thin film is formed on the surface of the substrate. That is, since the thin film is formed while the substrate is being transported, the throughput is high.

Patent Literature 2 discloses a plasma deposition apparatus. This plasma film forming apparatus includes an airtight container having a gas inlet, a plurality of electrodes, and a workpiece holder. The work holding unit holds a work, which is an object to be film-formed, in a stationary state inside the closed container. A plurality of electrodes are arranged above the workpiece holder so as to be vertically movable. Each electrode and work holder function as a counter electrode that causes an electric discharge within the sealed container. Each electrode moves up and down according to the irregularities on the surface of the workpiece. When a high-frequency voltage is applied to the electrodes while the work is held stationary on the work holding portion, electric discharge and plasma are generated in the sealed container, forming a thin film on the surface of the work.

In Patent Document 2, since the electrodes can be moved up and down, it is possible to suppress variations in the facing distance between each electrode and the workpiece. Therefore, variations in plasma intensity distribution on the surface of the workpiece can be suppressed, and a thin film having a more uniform thickness can be formed on the surface of the workpiece.

JP 2015-74792 A JP 2010-168604 A

When the surface of the object to be processed to be plasma-processed is not flat and has a three-dimensional shape, it is difficult to form a thin film with a more uniform thickness using the technique described in Patent Document 1. . In a more general concept, it is difficult to adjust the plasma intensity distribution on the surface to be processed over a wide range.

On the other hand, the technique described in Patent Document 2 can form a thin film with a more uniform thickness by vertically moving the electrode with respect to the stationary object to be processed. However, in Patent Document 2, the workpiece is processed in a stationary state, so the throughput is low.

Accordingly, an object of the present application is to provide a plasma processing apparatus and a plasma processing method capable of performing plasma processing with high throughput while adjusting the plasma intensity distribution on the surface to be processed.

In order to solve the above problems, a first aspect of a plasma processing apparatus is a plasma processing apparatus that applies plasma to a surface of an object to be processed, comprising: a chamber; and a holding/conveying unit for conveying the object to be processed along the conveying path; an electrode provided at a position facing the surface of the object to be processed in the middle of the conveying path in the vertical direction; An elevating unit that raises and lowers an electrode, a power supply unit that supplies power to the electrode, a gas introduction pipe that introduces gas into the chamber, and a state in which the power is supplied to the power supply unit to generate plasma. while controlling the holding/transporting unit to transport the object to be processed along the transport path, controlling the lifting unit to determine the transport position of the object to be processed based on the shape of the surface to be processed; and a control unit for raising and lowering the electrode in response to the elevation , wherein the chamber includes a fixed plate having a through hole extending in the vertical direction formed thereon, and a cylindrical shape that can be expanded and contracted in the vertical direction, a peripheral edge portion on one end side of the cylindrical shape is connected to the movable plate, and a peripheral edge portion on the other end side of the cylindrical shape A portion includes a bellows connected to a peripheral portion of the fixed plate surrounding the through hole, and the electrode is fixed to the movable plate .

A second aspect of the plasma processing apparatus is the plasma processing apparatus according to the first aspect, further comprising a storage medium for storing the shape of the surface to be processed of the object to be processed.

A third aspect of the plasma processing apparatus is the plasma processing apparatus according to the first or second aspect, wherein the plasma processing apparatus is provided upstream of the transport path from the electrode, and the object to be processed is held and transported. A sensor is further provided for measuring the shape of the surface to be treated while held by the part.

A fourth aspect of the plasma processing apparatus is the plasma processing apparatus according to any one of the first to third aspects, wherein the introduction port of the gas introduction pipe through which gas is introduced into the chamber includes the electrode and the gas introduction pipe moves up and down together with the electrode.

A fifth aspect of the plasma processing apparatus is the plasma processing apparatus according to any one of the first to fourth aspects, wherein the electrodes are provided at positions sandwiching the electrodes from opposite sides in the extending direction of the transport path. A pair of partition members are further provided, and the pair of partition members move up and down together with the electrodes.

A mode of the plasma processing method is a plasma processing method in which a plasma is applied to a surface of an object to be processed . a movable plate disposed at a position; and a cylindrical shape that can be expanded and contracted in the vertical direction, the peripheral edge portion of one end side of the cylindrical shape is connected to the movable plate, and the peripheral edge portion of the other end side of the cylindrical shape is connected to the movable plate. a step of introducing a gas into a chamber including a bellows connected to a peripheral portion of the fixing plate surrounding the through hole ; a step of generating plasma by supplying electric power to an electrode arranged to face the surface to be processed in a vertical direction and fixed to the movable plate ; conveying the object to be processed along the conveying path while raising and lowering the movable plate according to the conveying position of (1) to raise and lower the electrode;

According to the first and second aspects of the plasma processing apparatus and the aspect of the plasma processing method, the plasma can be applied to the surface of the object to be processed while the object to be processed is being transported, so plasma processing can be performed with high throughput. It can be carried out.

Moreover, the distance between the surface to be processed and the electrode can be dynamically adjusted while the object to be processed is being transported. Therefore, it is possible to control the plasma intensity distribution in the transport direction on the surface to be processed. For example, by moving the electrode so that the distance between the surface to be processed and the electrode is substantially constant, variations in plasma intensity distribution on the surface to be processed can be suppressed. Furthermore, the electrodes can be attached to the chamber so as to be able to move up and down.

According to the third aspect of the plasma processing apparatus, the sensor measures the shape of the surface to be processed while being held by the holding/conveying section. Therefore, the controller can raise and lower the electrode according to the shape of the surface to be treated with high accuracy.

According to the fourth aspect of the plasma processing apparatus, it is possible to further reduce variations in plasma intensity distribution on the surface to be processed.

According to the fifth aspect of the plasma processing apparatus, it is possible to further reduce variations in plasma intensity distribution on the surface to be processed.

It is a figure which shows roughly an example of a structure of a plasma processing apparatus. FIG. 4 is a diagram for explaining an example of an arrangement of inductively coupled antennas arranged along a virtual axis; 1 is a diagram schematically showing an example of an inductively coupled antenna; FIG. It is a flow chart which shows an example of operation of a plasma treatment apparatus. It is a figure which shows roughly an example of the state inside the plasma processing apparatus during plasma processing. It is a figure which shows roughly an example of the state inside the plasma processing apparatus during plasma processing. It is a figure which shows roughly an example of the state inside the plasma processing apparatus during plasma processing. It is a figure which shows roughly an example of the state inside the plasma processing apparatus during plasma processing. 4 is a graph showing an example of change in height position of an inductively coupled antenna; It is a figure which shows roughly another example of a structure of a plasma processing apparatus.

Hereinafter, embodiments will be described based on the drawings. In the drawings, parts having similar configurations and functions are denoted by the same reference numerals, and redundant description will be omitted in the following description. In addition, each drawing is schematically shown, and for ease of understanding, the dimensions and numbers of each part may be exaggerated or simplified. Also, XYZ orthogonal coordinate axes are appropriately attached to some of the drawings in order to explain the directions. The direction of the Z-axis in these coordinate axes indicates the direction of the vertical line, and the XY plane is the horizontal plane. Also, each of the X-axis and the Y-axis is parallel to the side wall of the chamber 1 . Further, hereinafter, one direction in the Y-axis direction is also called the +Y direction, and the other direction is also called the -Y direction.

First embodiment.
<Overall Configuration of Plasma Processing Apparatus 100>
FIG. 1 is a diagram schematically showing an example of the configuration of a plasma processing apparatus 100. As shown in FIG. The plasma processing apparatus 100 is an apparatus that generates plasma and causes the plasma to act on the processing target surface 9 a of the processing target 9 . As such a plasma processing apparatus 100, a plasma film forming apparatus that forms a film on the processing target surface 9a by plasma CVD (Plasma-enhanced Chemical Vapor Deposition) can be exemplified. In the following, the plasma film deposition apparatus will be described as an example of the plasma processing apparatus 100 .

The processing target surface 9a of the processing target 9 is not flat, for example, and has a three-dimensional shape. An example of such an object 9 to be processed may be a front window or a rear window of a vehicle. A silicon oxide film or a silicon nitride film can be exemplified as the type of film formed on the surface 9a to be processed. In addition, the processing object 9 is not limited to the above example, and may be changed as appropriate. Similarly, the type of film formed on the processing object 9 is not limited to the above example, and may be changed as appropriate.

The plasma processing apparatus 100 includes a chamber 1 , a holding/transporting section 2 , a plasma generating section 4 , a gas introduction section 61 , an elevating section 7 and a control section 8 . Below, each configuration will be described in detail after an outline of each configuration is given.

<Overview of each configuration>
The chamber 1 forms a processing space V inside it. In this processing space V, plasma processing is performed on the processing object 9 . The holding/conveying unit 2 holds the processing object 9 in the processing space V and conveys the processing object 9 along a predetermined conveying path Y1. The gas introduction part 61 introduces gas into the processing space V. As shown in FIG. As the gas, a gas corresponding to the type of film to be formed on the processing target surface 9a of the processing target 9 is appropriately employed.

The plasma generator 4 includes an electrode 41 for plasma generation. The electrode 41 is provided at a position facing the processing target surface 9a of the processing target 9 being transported in the middle of the transport path Y1. According to this, the processing object 9 is transported across the electrodes 41 . Also, the electrode 41 is provided in the chamber 1 so as to be movable up and down. The elevating unit 7 elevates the electrode 41 .

Electric power for plasma generation is supplied to the electrode 41 by a power supply unit 45 . As a result, the gas is turned into plasma in the processing space V, and the plasma acts on the processing target surface 9a of the processing target 9 being transported.

During the transportation of the object 9 to be treated, the elevating unit 7 raises and lowers the electrode 41 according to the shape of the surface 9a to be treated. As a more specific example, the lifting unit 7 lifts and lowers the electrode 41 so that the distance between the electrode 41 and the processing target surface 9a (the distance along the Z-axis direction) is maintained substantially constant (see FIG. 5). See also Figure 8).

According to this plasma processing apparatus 100, since the processing target surface 9a is plasma-processed while the processing target 9 is transported, the throughput is high. Moreover, by moving the electrode 41 up and down so that the distance between the electrode 41 and the surface 9a to be processed is substantially constant, variations in plasma intensity distribution on the surface 9a to be processed can be reduced. Therefore, a thin film can be formed on the processing target surface 9a with a more uniform film thickness.

An example of each configuration will be described in detail below.

<Chamber 1>
The chamber 1 is a hollow member having a rectangular parallelepiped outer shape and forms a processing space V inside. In the processing space V, a transport path Y1 for the object 9 to be processed by the holding/transporting section 2 is defined. The extending direction of the transport path Y1 is the Y-axis direction, and the transport direction of the processing object 9 on the transport path Y1 is the +Y direction. Of the two ends of the chamber 1 along the transport path Y1, the upstream end in the transport direction is provided with a carry-in port 121 for transporting the object to be processed 9 into the chamber 1, and the downstream end in the transport direction is provided. is provided with a carry-out port 122 for carrying out the processing object 9 out of the chamber 1 . A gate (“loading gate”) 123 is provided at the loading port 121 on the upstream side, and a gate (“loading gate”) 124 is provided at the loading port 122 on the downstream side. Each gate 123, 124 can be switched between an open state and a closed state. In addition, each of the loading port 121 and the loading port 122 is configured to be airtightly connectable to an opening of another chamber such as a load lock chamber or an unload lock chamber.

<Holding and Conveying Unit 2>
Here, the processing target 9 is arranged on the upper surface of a plate-shaped carrier 90 . The carrier 90 is arranged so that its thickness direction is along the Z-axis direction. The processing object 9 is placed on the upper surface of the carrier 90 with the processing object surface 9a facing upward. In the example of FIG. 1, the processing target surface 9a of the processing target 9 has an upwardly convex curved shape.

The holding/conveying unit 2 holds the carrier 90 carried into the processing space V through the carry-in port 121 of the chamber 1 (that is, the carrier 90 on which the object 9 to be processed is arranged), and transports it to the processing space V. It is transported along a substantially horizontal transport path Y1 defined inside.

The holding/conveying section 2 specifically includes, for example, a pair of conveying rollers 21 and a driving section (not shown). The pair of transport rollers 21 are arranged on both sides of the transport path Y1 in the width direction (the X-axis direction in the illustrated example), and face each other in the X-axis direction. For example, a plurality of pairs of transport rollers 21 are provided along the extending direction of the transport path Y1 (the Y-axis direction in the illustrated example). The drive unit synchronously drives the conveying rollers 21 to rotate. In this configuration, the carrier 90 is conveyed along the conveying path Y1 in the processing space V by rotating each conveying roller 21 in contact with the lower surface of the carrier 90 . That is, the processing object 9 held by the carrier 90 is transported along the transport path Y1.

<Plasma generator 4>
The plasma generator 4 generates plasma within the processing space V. As shown in FIG. The plasma generator 4 includes an electrode 41 for generating plasma. This electrode 41 is provided in the middle of the transport path Y1, for example above the transport path Y1. The electrode 41 is, for example, an inductive coupling type antenna, which is an inductive coupling type high frequency antenna. The electrode 41 is hereinafter also referred to as an inductively coupled antenna 41 .

An inductively coupled antenna 41 is provided in the chamber 1 so as to be able to move up and down. In the illustrated example, the top plate 11 of the chamber 1 includes a fixed plate 111 , a movable plate 112 and a bellows 113 . The fixed plate 111 mainly constitutes the top plate 11 . A through hole 111 a is formed in the fixing plate 111 . The through-hole 111 a extends in the Z-axis direction and penetrates the fixed plate 111 . The through-hole 111a is formed in the fixed plate 111 so as to include the inductively coupled antenna 41 in plan view (that is, when viewed along the Z-axis direction).

The movable plate 112 is provided at a position facing the through hole 111a of the fixed plate 111 in the Z-axis direction. In the example of FIG. 1 , the movable plate 112 is provided above the through hole 111 a of the fixed plate 111 .

The bellows 113 has a substantially cylindrical shape, and its side surface is formed in a bellows shape. The bellows 113 is provided with its central axis along the Z-axis direction, and can be expanded and contracted along the Z-axis direction. A peripheral edge portion on one end side of the bellows 113 is airtightly connected to a peripheral edge portion of the movable plate 112, and a peripheral edge portion on the other end side is airtightly connected to a peripheral edge portion of the fixed plate 111 forming the through hole 111a. there is

According to such a chamber 1 , the movable plate 112 can move up and down with respect to the fixed plate 111 while maintaining the airtightness of the chamber 1 . The movable plate 112 is connected to the elevating section 7 . The elevating unit 7 has, for example, a ball screw mechanism, and elevates the movable plate 112 to control its height position.

The inductive coupling antenna 41 is, for example, a metal pipe-shaped conductor bent into a U shape, and protrudes inside the processing space V in a "U" shape. The projecting portion of the inductively coupled antenna 41 is covered with a dielectric protection pipe 42 made of quartz or the like. The upper end of the inductive coupling antenna 41, that is, both ends of the inductive coupling antenna 41 penetrate the top plate 11 (more specifically, the movable plate 112) of the chamber 1 and protrude upward. Also, the inductively coupled antenna 41 is cooled by, for example, circulating cooling water inside.

Since the inductive coupling antenna 41 is fixed to the movable plate 112 , the inductive coupling antenna 41 can be raised and lowered by raising and lowering the movable plate 112 by the elevating section 7 . That is, the height position of the inductively coupled antenna 41 can be controlled.

In the example of FIG. 1, a plurality of inductively coupled antennas 41 are provided. Therefore, the top plate 11 of the chamber 1 includes a plurality of movable plates 112 and a plurality of bellows 113 corresponding to the number of the inductive coupling antennas 41, and the fixed plate 111 has the number of the inductive coupling antennas 41. A plurality of through holes 111a are formed accordingly. Each set of movable plate 112 and bellows 113 is attached to fixed plate 111 in the positional relationship described above, and inductively coupled antenna 41 is fixed to movable plate 112, respectively. Also, the plurality of movable plates 112 are connected to the plurality of elevating units 7, respectively. According to this, the plurality of movable plates 112 and, in turn, the plurality of inductively coupled antennas 41 can be raised and lowered independently of each other.

The plurality of inductively coupled antennas 41 are arranged at intervals (preferably at equal intervals) along a predetermined direction and fixed to the top plate 11 (more specifically, the movable plate 112). be done. Specifically, the plurality of inductively coupled antennas 41 are arranged in the chamber 1 so as to face the transport path Y1 along the extending direction of the transport path Y1 and a virtual axis K (see also FIG. 2) described later. Arranged in a matrix. For example, a line in which four inductively coupled antennas 41 are arranged in one line along the imaginary axis K is arranged in three lines along the direction of the transport path Y1.

In addition, in the chamber 1, only one row in which a plurality of inductively coupled antennas 41 are arranged in one row along the virtual axis K may be provided along the direction of the transport path Y1. Only one row may be provided along the imaginary axis K, in which the plurality of inductively coupled antennas 41 are arranged in one row along the direction of the transport path Y1. Also, only one inductive coupling antenna 41 may be provided in the chamber 1 . That is, in the chamber 1, at least one inductive coupling antenna 41 is provided facing the transport path Y1.

FIG. 2 is a diagram for explaining an example of the arrangement of the inductively coupled antennas 41 arranged along the virtual axis K in the plasma processing apparatus 100. As shown in FIG. In FIG. 2, illustration of the top plate 11 is omitted. As described above, in the chamber 1, a row in which a plurality of (four in the example of FIG. 2) inductively coupled antennas 41 are arranged along the imaginary axis K extends in the direction in which the transport path Y1 extends. A plurality (three rows in the example of FIG. 1, and three virtual axes K are set) may be provided along the line, and FIG. 2 shows one of the plurality of rows.

Specifically, as shown in FIG. 2, by arranging the center point C of a line segment L connecting both ends of each of the plurality of inductively coupled antennas 41 on the virtual axis K, a plurality of inductively coupled antennas 41 are arranged. The type antennas 41 are arranged in one row along the imaginary axis K. FIG. However, the virtual axis K is preferably an axis extending in a direction intersecting the extending direction (Y-axis direction) of the transport path Y1. is preferably an axis substantially parallel to .

In addition, in the example of FIG. 2, four inductive coupling antennas 41 are provided along the virtual axis K, but the number of inductive coupling antennas 41 arranged along the virtual axis K is necessarily four. It is not necessary, and the number can be appropriately selected according to the dimensions of the chamber 1 and the like. Similarly, in the example of FIG. 1, three rows of four inductively coupled antennas 41 arranged along the imaginary axis K are provided along the extending direction of the transport route Y1. need not be provided. Also, the inductively coupled antennas 41 do not necessarily have to be arranged in a matrix, and may be arranged in a zigzag pattern, for example.

<Power supply unit 45>
A power supply unit 45 supplies power for plasma generation to the inductively coupled antenna 41 . In the example of FIG. 1, a plurality of power supply units 45 are provided corresponding to a plurality of inductively coupled antennas 41 . In the example of FIG. 1, each power supply 45 includes a matching box 43 and a high frequency power supply 44 . A high frequency power supply 44 supplies high frequency power to the inductively coupled antenna 41 via the matching box 43 .

One end of each inductively coupled antenna 41 is connected to a high frequency power supply 44 via a matching box 43 . The other end of each inductive coupling antenna 41 is grounded. In this configuration, when a high-frequency current (specifically, a high-frequency current of 13.56 MHz, for example) flows from the high-frequency power supply 44 to each inductive coupling antenna 41, an electric field around the inductive coupling antenna 41 (high-frequency induction electric field ) accelerates electrons to generate plasma (inductively coupled plasma (ICP)).

As described above, the inductively coupled antenna 41 has a U shape. Such a U-shaped inductive coupling antenna 41 corresponds to an inductive coupling antenna having less than one turn, and has a lower inductance than an inductive coupling antenna having one or more turns. is reduced, and the high-frequency oscillation of the plasma potential due to electrostatic coupling to the generated plasma is suppressed. As a result, excessive electron loss associated with plasma potential fluctuations to the ground potential is reduced, and the plasma potential is suppressed to a particularly low level. Such inductive coupling type high-frequency antennas are disclosed in Japanese Patent No. 3836636, Japanese Patent No. 3836866, Japanese Patent No. 4451392, and Japanese Patent No. 4852140.

As wiring that connects the matching box 43 and the inductively coupled antenna 41, a bendable wiring (for example, an electric wire) is employed. Thereby, the inductive coupling antenna 41 can be raised and lowered while maintaining the electrical connection between the matching box 43 and the inductive coupling antenna 41 .

<Partition member 5>
In the example of FIG. 1, a partition member 5 is provided inside the chamber 1 . The partition members 5 are provided on the upstream side and the downstream side of the transport path Y1 with respect to one inductive coupling antenna 41, respectively. The partition member 5 moves the processing space V in the chamber 1 (more specifically, part of the processing space V on the top plate 11 side of the chamber 1) to the upstream side of the transport path Y1 with respect to the partition member 5. It is a member that partitions into a space on the downstream side and a space on the downstream side.

The partition member 5 protrudes downward (−Z direction) from the top plate 11 of the chamber 1 . The partition member 5 has a plate-like shape, for example, and is provided so that its thickness direction is along the transport path Y1. The partition member 5 is made of a dielectric. Between the upper surface of the carrier 90 and the lower end of the partition member 5, a gap is provided through which the object 9 to be processed can pass.

The plasma generated in the processing space V stays in a space defined by a pair of partition members 5 provided facing each other on the upstream side and the downstream side of the inductive coupling antenna 41 in the processing space V. the intensity of the plasma increases. When a plurality of inductive coupling antennas 41 are provided along the virtual axis K, each partition member 5 corresponding to each inductive coupling antenna 41 is provided.

The partition member 5 may also be attached to the chamber 1 so as to be movable up and down. In the example of FIG. 1 , the partition member 5 protrudes from the lower surface of the movable plate 112 of the chamber 1 . That is, one inductively coupled antenna 41 and a pair of partition members 5 are fixed to one movable plate 112 . FIG. 3 is a diagram of one inductively coupled antenna 41 viewed along the Y-axis direction. In the example of FIG. 3, the movable plate 112, the partition member 5, and the gas introduction pipe 62, which will be described later, are also shown. In the example of FIG. 3, the partition member 5 has a rectangular shape when viewed along the Y-axis direction. As shown in FIG. 3 , the width of the partition member 5 (the width along the X-axis direction) may be set wider than the width of the inductively coupled antenna 41 . Also, the length of the partition member 5 (the length along the Z-axis direction) may be set longer than the amount of protrusion of the inductive coupling antenna 41 from the lower surface of the movable plate 112 .

If the partition member 5 is fixed to the movable plate 112 in this manner, the partition member 5 also moves up and down as the movable plate 112 moves up and down. That is, the pair of partition members 5 moves up and down integrally with the inductive coupling antenna 41 .

<Gas supply unit 6 and gas introduction unit 61>
Referring to FIG. 1 again, the gas supply unit 6 supplies a gas determined according to the purpose of the plasma processing apparatus 100, for example, a raw material gas (specifically, silane (SiH ₄ ) or ammonia (for example, silane (SiH 4 )) as a processing gas. NH ₃ )) and, for example, an additive gas (specifically, for example, argon (Ar), oxygen (O ₂ ), hydrogen (H ₂ ), or a mixed gas thereof) are introduced into the processing space V through the gas introduction portion 61. supply to Specifically, the gas supply unit 6 includes, for example, a gas supply source 611 and an introduction pipe 612 having one end connected to the gas supply source 611 .

In the processing space V, as described above, a space defined by a pair of partition members 5 facing each other with the inductive coupling antenna 41 interposed therebetween is formed. communicates the introduction pipe 612 and the processing space V with each other. Each gas introduction pipe 62 forms a gas introduction portion 61 . The opening of the gas introduction pipe 62 in the processing space V is hereinafter referred to as an introduction port 62a (see also FIG. 3).

The introduction pipe 612 of the gas supply section 6 is connected to each gas introduction pipe 62 of the gas introduction section 61 . A supply valve 613 is inserted in the middle of the path of the introduction pipe 612 . The supply valve 613 is preferably a valve capable of automatically adjusting the flow rate of the gas flowing through the introduction pipe 612. Specifically, for example, it preferably includes a mass flow controller or the like. In this configuration, when the supply valve 613 is opened, the gas supplied from the gas supply source 611 is supplied to each gas introduction portion 61 through the introduction pipe 612, and the gas introduction pipe 62 of each gas introduction portion 61 is introduced. It is discharged into the processing space V from the port 62a.

The gas introduction pipe 62 is provided corresponding to the inductive coupling antenna 41 , and the introduction port 62 a thereof is arranged in the processing space V at a position adjacent to the corresponding inductive coupling antenna 41 . More specifically, the gas introduction pipe 62 is provided so as to be adjacent to the inductive coupling antenna 41 in the space where the introduction port 62 a is sandwiched between the pair of partition members 5 .

What kind of gas and at what flow rate are to be introduced from the gas introduction part 61 are appropriately selected according to, for example, the type of thin film to be formed on the object to be processed 9, the processing conditions, the details of the processing, and the like. . That is, the supply valve 613 is electrically connected to the control unit 8, and the control unit 8 controls the supply valve 613 based on a value or the like designated by the operator to supply the type of gas designated by the operator. , is introduced into the processing space V from the gas introduction portion 61 at a flow rate designated by the operator.

The gas introduction pipe 62 may also be provided so as to be able to move up and down. In the example of FIG. 1, the gas introduction pipe 62 penetrates through the movable plate 112 of the chamber 1 and is fixed to the movable plate 112 . At least a portion of the gas introduction pipe 62 between the introduction pipe 612 and the movable plate 112 is formed of a bendable member. According to such a configuration, when the movable plate 112 moves up and down, the gas introduction pipe 62 fixed to the movable plate 112 (more specifically, the portion of the gas introduction pipe 62 inside the chamber 1) also moves up and down. That is, the gas introduction pipe 62 (more specifically, the portion inside the chamber 1) moves up and down integrally with the inductively coupled antenna 41. As shown in FIG.

<Heating part 3>
In the example of FIG. 1, a heating section 3 is provided within the processing space V of the chamber 1 . The heating unit 3 is a member that heats the processing object 9 held and transported by the holding and transporting unit 2, and is positioned below the holding and transporting unit 2 (i.e., below the transport path Y1 of the processing object 9). is provided. The heating unit 3 can be composed of, for example, a ceramic heater. In addition, the plasma processing apparatus 100 may further include a mechanism for cooling the processing object 9 held by the holding/conveying unit 2 .

<Exhaust part 65>
In the example of FIG. 1, an exhaust section 65 is provided. The exhaust unit 65 is a high-vacuum exhaust system, and specifically includes, for example, a vacuum pump, an exhaust pipe, and an exhaust valve, all of which are not shown. The exhaust pipe has one end connected to a vacuum pump and the other end connected to the processing space V. FIG. Also, the exhaust valve is provided 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 in operation, the processing space V is evacuated. Control to maintain pressure.

<Control unit 8>
The control unit 8 is electrically connected to each component included in the plasma processing apparatus 100 and controls each component. More specifically, the control unit 8 controls the holding/conveying unit 2 , the power supply unit 45 , the supply valve 613 , the exhaust unit 65 and the lifting unit 7 . Specifically, the control unit 8 includes, for example, a CPU (Central Processing Unit) that performs various arithmetic processing, a storage medium 81 (for example, a ROM (Read Only Memory) that stores programs and the like, and a RAM that serves as a work area for arithmetic processing. (random access memory) and a hard disk for storing programs and various data files), a data communication unit having a data communication function via a LAN (Local Area Network), etc. are connected to each other by a bus, etc. It consists of an FA (Factory Automation) computer. The control unit 8 is also connected to a display for displaying various information, an input unit including a keyboard and a mouse, and the like. In the plasma processing apparatus 100 , under the control of the control unit 8 , a predetermined process is performed on the processing object 9 .

<Lift Control of Inductively Coupled Antenna 41>
FIG. 4 is a flow chart showing an example of the operation of the plasma processing apparatus 100. FIG. First, in step S1, the control unit 8 controls the exhaust unit 65 to exhaust the gas inside the chamber 1 to the outside so that the pressure inside the chamber 1 is within a predetermined range (process pressure).

Next, in step S<b>2 , the control unit 8 opens the supply valve 613 of the gas supply unit 6 to discharge the gas into the processing space V from the introduction port 62 a of the gas introduction pipe 62 .

Next, in step S<b>3 , the control unit 8 causes the power supply unit 45 to supply high-frequency power to the inductively coupled antenna 41 . As a result, the gas around the inductively coupled antenna 41 is turned into plasma.

Next, in step S4, the control section 8 controls the heating section 3 to generate heat. Note that step S4 does not necessarily have to be performed after step S3, and may be performed before step S3.

Next, in step S5, the control unit 8 controls the lifting unit 7 to raise and lower the inductively coupled antenna 41, and controls the holding/conveying unit 2 to convey the processing object 9 along the conveying path Y1. . Specifically, the control unit 8 controls the height position of the inductive coupling antenna 41 according to the transport position of the processing target 9 based on the shape of the processing target surface 9 a of the processing target 9 . That is, the control unit 8 dynamically controls the height position of the inductively coupled antenna 41 while the processing object 9 is being transported.

For example, the control unit 8 adjusts the height of the inductive coupling antenna 41 so that the distance between the inductive coupling antenna 41 and the processing target surface 9a of the processing target 9 (distance along the Z-axis direction) is substantially constant. position control.

5 to 8 are diagrams schematically showing an example of the internal state of the plasma processing apparatus 100 during plasma processing. 5 to 8 show the internal state of the plasma processing apparatus 100 in chronological order. 5 shows the state inside the plasma processing apparatus 100 at the earliest timing, and FIG. 8 shows the state inside the plasma processing apparatus 100 at the latest timing.

The three inductively coupled antennas 41 arranged along the Y-axis direction are hereinafter also referred to as inductively coupled antennas 41A to 41C. The inductive coupling antenna 41A is located at the end in the -Y direction, the inductive coupling antenna 41C is located at the end in the +Y direction, and the inductive coupling antenna 41B is located between the inductive coupling antenna 41A and the inductive coupling antenna 41C. positioned.

Further, hereinafter, "A" to "C" may be added to the end of the reference numerals in order to distinguish the partition member 5, the gas introduction pipe 62, and the lifting section 7 corresponding to the inductive coupling type antenna 41 from each other. For example, the partition member 5A is the partition member 5 provided corresponding to the inductive coupling antenna 41A.

In the example of FIG. 5, the processing object 9 is positioned directly below the inductive coupling antenna 41A and has not yet reached directly below the inductive coupling antenna 41B and the inductive coupling antenna 41C. Therefore, the control unit 8 controls the lifting unit 7A so that the distance between the inductively coupled antenna 41A and the processing target surface 9a of the processing target 9 substantially coincides with the predetermined value D1. In the example of FIG. 5, the height positions of the inductive coupling antenna 41B and the inductive coupling antenna 41C are controlled to the initial positions.

In the example of FIG. 6, the processing object 9 is positioned directly below the inductively coupled antenna 41A and the inductively coupled antenna 41B, and has not yet reached directly below the inductively coupled antenna 41C. Therefore, the control unit 8 controls the elevation unit 7A and the elevation unit 7B so that the distances between the inductive coupling antenna 41A and the inductive coupling antenna 41B and the surface to be processed 9a substantially coincide with the predetermined value D1. to control. In the example of FIG. 6, the inductive coupling antenna 41A faces the vicinity of the top of the processing target surface 9a, and the inductive coupling antenna 41B faces the vicinity of the end of the processing target surface 9a. The height position of 41A is higher than the inductively coupled antenna 41B. On the other hand, in the example of FIG. 6, the height position of the inductive coupling antenna 41C is controlled to the initial position.

In the example of FIG. 7, the processing object 9 is located directly under the inductive coupling antenna 41A to the inductive coupling antenna 41C. Therefore, the control section 8 moves the elevation section 7A to the elevation section 7C so that the distances between the inductive coupling antennas 41A to 41C and the surface to be processed 9a substantially coincide with the predetermined value D1. to control. In the example of FIG. 7, the inductive coupling antenna 41B faces the vicinity of the apex of the surface 9a to be processed, and the inductive coupling antenna 41A and the inductive coupling antenna 41C are located near the opposite ends of the surface 9a to be processed. are facing Therefore, the height position of the inductive coupling antenna 41B is higher than both the inductive coupling antenna 41A and the inductive coupling antenna 41C.

In the example of FIG. 8, the processing object 9 has passed directly under the inductive coupling antenna 41A and is positioned directly under the inductive coupling antenna 41B and the inductive coupling antenna 41C. Therefore, the control unit 8 moves the elevators 7B and 7C so that the distances between the inductively coupled antennas 41B and 41C and the surface to be processed 9a substantially coincide with the predetermined value D1. Control. In the example of FIG. 8, the height position of the inductively coupled antenna 41A is controlled to the initial position.

FIG. 9 is a graph showing an example of changes in the height position of the inductively coupled antenna 41A during the plasma processing described above. In the example of FIG. 9, the transport position of the processing object 9 is adopted on the horizontal axis. The transport positions y1 to y4 correspond to FIGS. 5 to 8, respectively.

In the above example, the height position of the inductive coupling antenna 41A is controlled so that the distance between the inductive coupling antenna 41A and the processing target surface 9a substantially matches the predetermined value D1. Therefore, as illustrated in FIG. 9, the graph showing the height position of the inductive coupling antenna 41A shows the shape of the surface 9a to be processed and It also has an upwardly convex shape. The waveforms of the graphs showing the height positions of the inductive coupling antenna 41B and the inductive coupling antenna 41C are obtained by appropriately translating the graph of FIG. 9 along the horizontal axis.

Information indicating the relationship between the height position of the inductively coupled antenna 41 and the transport position of the processing target 9 (hereinafter also referred to as control information) may be set in advance according to, for example, the shape of the processing target surface 9a. good. It can be said that this control information is data indicating the shape of the surface 9a to be processed. The control information may be stored in advance in the storage medium 81 of the control section 8 . The control unit 8 refers to the control information and controls the holding/conveying unit 2 and the lifting unit 7 as described above.

As described above, in the plasma processing apparatus 100, plasma is caused to act on the surface 9a to be processed while the processing target 9 is being transported. Therefore, plasma processing (here, film formation processing) can be performed with high throughput.

Moreover, the control unit 8 controls the height position of the inductively coupled antenna 41 according to the shape of the surface 9a to be processed. For example, the control unit 8 controls the height position of each inductive coupling antenna 41 so that the distance between each inductive coupling antenna 41 and the processing target surface 9a substantially matches the predetermined value D1. According to this, it is possible to suppress variations in plasma intensity distribution on the surface 9a to be processed during transportation. Therefore, a thin film can be formed on the processing target surface 9a with a more uniform film thickness.

Moreover, in the above example, the partition member 5 also moves up and down integrally with the corresponding inductive coupling antenna 41 . For example, the pair of partition members 5A moves up and down together with the inductive coupling antenna 41A. According to this, the distance between the space sandwiched by the pair of partition members 5 in which plasma is generated with high intensity and the surface 9a to be processed is also controlled to be substantially constant during the transportation of the object 9 to be processed. .

For comparison, consider a structure in which a pair of partition members 5 are fixed to the top plate 11 (fixed plate 111) of the chamber 1 so as not to move up and down. In this configuration, the inductively coupled antenna 41 moves up and down relative to the pair of partition members 5 . Therefore, the plasma intensity distribution in the space sandwiched by the pair of partition members 5 fluctuates according to the height position of the inductively coupled antenna 41 . As a result, the plasma intensity distribution on the processing target surface 9a may also vary.

On the other hand, if the pair of partition members 5 moves up and down together with the inductively coupled antenna 41, fluctuations in the plasma intensity distribution in the space sandwiched by the pair of partition members 5 can be reduced. Further, since the distance between the space and the surface 9a to be processed is also kept substantially constant, variations in the plasma intensity distribution on the surface 9a to be processed can be further suppressed. Therefore, a thin film can be formed on the processing target surface 9a with a more uniform film thickness.

Further, in the above example, the gas introduction pipe 62 (specifically, the portion inside the chamber 1) also moves up and down together with the corresponding inductive coupling antenna 41 . For example, the gas introduction pipe 62A moves up and down integrally with the inductive coupling antenna 41A. According to this, the distance between the introduction port 62a of the gas introduction pipe 62 and the surface 9a to be processed is also controlled to be substantially constant during the transportation of the object 9 to be processed. As a result, variations in plasma intensity distribution on the processing target surface 9a during transportation can be further suppressed. Therefore, a thin film can be formed on the processing target surface 9a with a more uniform film thickness.

Second embodiment.
FIG. 10 is a diagram schematically showing an example of the configuration of the plasma processing apparatus 100A. The plasma processing apparatus 100A has the same configuration as the plasma processing apparatus 100 except for the sensor 75. As shown in FIG. The sensor 75 is provided upstream of the inductive coupling antenna 41 in the transport direction (-Y direction) and above the transport path Y1. The sensor 75 measures the shape of the processing target surface 9 a of the processing target 9 while the processing target 9 is being held by the holding/conveying unit 2 . The sensor 75 outputs shape data indicating the measurement result to the control section 8 .

The sensor 75 may be, for example, a non-contact distance sensor using electromagnetic waves or ultrasonic waves. In this case, the sensor 75 transmits a measurement wave, which is an ultrasonic wave or an electromagnetic wave, downward (-Z direction) and receives the measurement wave reflected by the object. The sensor 75 can measure the distance between the sensor 75 and the object based on the timing of transmitting the measurement wave and the timing of receiving the measurement wave.

In the example of FIG. 10 , the measurement wave transmitted by the sensor 75 is reflected by the processing target surface 9 a of the processing target 9 being transported by the holding/transporting section 2 and received by the sensor 75 . The time series distance data obtained by the sensor 75 when the processing object 9 crosses directly under the sensor 75 indicates the shape of the processing target surface 9 a of the processing object 9 . Therefore, the sensor 75 outputs the distance data to the controller 8 as shape data.

The sensor 75 is preferably provided at a position aligned with the inductively coupled antenna 41 in the extending direction of the transport path Y1 (here, the Y-axis direction) when viewed along the Z-axis direction. Thereby, the sensor 75 can measure the shape of the portion facing the inductively coupled antenna 41 of the surface 9a to be processed. When a plurality of inductively coupled antennas 41 are arranged in the X-axis direction, it is preferable that a plurality of sensors 75 are provided corresponding to each inductively coupled antenna 41 . More specifically, each sensor 75 is provided side by side with the corresponding inductively coupled antenna 41 in the extending direction of the transport path Y1 in plan view.

The control unit 8 generates control information based on shape data input from the sensor 75 . The control information is information indicating the relationship between the height position of each inductively coupled antenna 41 and the transport position of the processing object 9, as illustrated in FIG. Based on the control information, the control unit 8 controls the lifting unit 7 as in the first embodiment. According to this, as in the first embodiment, variations in plasma intensity distribution on the processing target surface 9a of the processing target 9 can be suppressed.

Moreover, according to the second embodiment, the sensor 75 is provided at a position facing the transport path Y1, and measures the shape of the processing target surface 9a of the processing target 9 held by the holding/transporting section 2. ing. According to this, as described below, the height position of the inductively coupled antenna 41 can be controlled with higher accuracy according to the shape of the surface 9a to be processed.

Now, when the shape of the processing target surface 9a of the processing target 9 is measured at a measurement location different from the holding/conveying unit 2, the placement posture of the processing target 9 during measurement is the placement posture during plasma processing ( That is, it may be different from the holding attitude by the holding/conveying unit 2). For example, if the mounting surface at the measurement location is tilted with respect to the upper surface of the carrier 90 on the transport roller 21, the mounting attitude of the processing object 9 at the measurement location is different from the mounting attitude during plasma processing. become. If the height position of the inductively coupled antenna 41 is controlled using the shape data of the processing target surface 9a measured at the measurement location, the difference in the mounting posture can cause an error in the height position. As a result, the difference can be a factor in variations in plasma intensity distribution.

On the other hand, in the second embodiment, the sensor 75 measures the shape of the surface 9 a to be processed while the object 9 is being held by the holding/conveying unit 2 . In other words, the sensor 75 can measure the shape of the processing target surface 9a of the processing target 9 that takes substantially the same mounting posture as that during the plasma processing. Therefore, the control unit 8 can raise and lower the inductively coupled antenna 41 according to the shape of the surface 9a to be processed with high accuracy. Therefore, variations in plasma intensity distribution on the processing target surface 9a can be suppressed more appropriately, and a thin film having a more uniform film thickness can be formed on the processing target surface 9a.

Modification.
In the above example, the control unit 8 controls the lifting unit 7 so that the distance between the inductively coupled antenna 41 and the processing target surface 9a substantially coincides with the constant predetermined value D1. However, it is not necessarily limited to this. For example, the control unit 8 may control the lifting unit 7 so as to vary the intensity of the plasma according to each position on the surface 9a to be processed. As a more specific example, the control unit 8 adjusts the height position of each inductive coupling antenna 41 so that the plasma intensity near the top of the processing target surface 9a is greater than the plasma intensity near the edge. may be controlled.

In short, the control unit 8 may control the height position of the inductively coupled antenna 41 based on the transport position of the processing object 9 according to the shape of the processing object surface 9a. Thereby, plasma processing can be performed with high throughput while adjusting the plasma intensity distribution on the processing target surface 9a.

Further, in the above example, the plasma film forming apparatus is illustrated as the plasma processing apparatus 100, but it is not necessarily limited to this. For example, the plasma processing apparatus 100 may be a plasma processing apparatus for surface modification. Specifically, the plasma processing apparatus 100 plasma-processes the processing target surface 9a (metal surface) of the metal processing target 9 with a gas such as argon, nitrogen, hydrogen, or ammonia, thereby increasing the processing target. Modify the surface 9a. Thereby, the adhesion between the thin film formed on the processing target surface 9a and the processing target surface 9a can be improved.

Although the plasma processing apparatus has been shown and described in detail, the above description is illustrative in all aspects and not restrictive. Therefore, the plasma processing apparatus can be appropriately modified or omitted from the embodiments within the scope of the disclosure. Also, the above-described embodiments can be appropriately combined.

100, 100A Plasma processing apparatus 1 Chamber 2 Holding and transporting part 5 Partition member 7 Elevating part 41, 41A to 41C Electrode (inductively coupled antenna)
45 power supply unit 62 gas introduction pipe 111 fixed plate 112 movable plate 113 bellows

Claims (6)

A plasma processing apparatus that applies plasma to the surface of an object to be processed,
a chamber;
a holding and transporting unit that holds the object to be processed in the chamber and transports the object to be processed along a transport path;
an electrode provided at a position facing the processing target surface of the processing target in the middle of the transport path in the vertical direction;
an elevating unit that elevates the electrode;
a power supply unit that supplies power to the electrodes;
a gas introduction pipe for introducing gas into the chamber;
controlling the lifting unit while controlling the holding/transporting unit to transport the object to be processed along the transport path in a state in which the electric power is supplied to the power supply unit to generate plasma, a control unit that raises and lowers the electrode according to the transport position of the object to be processed based on the shape of the surface to be processed ;
The chamber is
a fixing plate formed with a through hole extending along the vertical direction;
a movable plate arranged at a position facing the through hole and connected to the elevating section;
It has a cylindrical shape that can be expanded and contracted in the vertical direction, a peripheral edge portion on one end side of the tubular shape is connected to the movable plate, and a peripheral edge portion on the other end side of the tubular shape is connected to the fixed plate. a bellows connected to a peripheral edge surrounding the through hole;
including
A plasma processing apparatus, wherein the electrode is fixed to the movable plate . The plasma processing apparatus according to claim 1,
A plasma processing apparatus comprising a storage medium for storing a shape of the surface to be processed of the object to be processed. The plasma processing apparatus according to claim 1 or 2,
A plasma processing apparatus further comprising a sensor provided on the upstream side of the transport path relative to the electrodes, the sensor measuring the shape of the surface of the object to be processed while the object to be processed is held by the holding/transporting unit. The plasma processing apparatus according to any one of claims 1 to 3 ,
an introduction port of the gas introduction pipe through which gas is introduced into the chamber is arranged at a position adjacent to the electrode;
The plasma processing apparatus, wherein the gas introduction pipe moves up and down together with the electrode. The plasma processing apparatus according to any one of claims 1 to 4 ,
further comprising a pair of partition members provided at positions sandwiching the electrodes from opposite sides in the extending direction of the transport path,
The plasma processing apparatus, wherein the pair of partition members move up and down together with the electrodes. A plasma processing method for applying plasma to the surface of an object to be processed,
A fixed plate formed with a through hole extending along the vertical direction, a movable plate arranged at a position facing the through hole, and a cylindrical shape that can be expanded and contracted in the vertical direction, and the cylindrical shape A chamber including a bellows whose peripheral edge portion on one end side is connected to the movable plate, and whose peripheral edge portion on the other end side of the cylindrical shape is connected to the peripheral edge portion of the fixed plate surrounding the through hole. introducing a gas;
Plasma is generated by supplying electric power to an electrode which is arranged at a position facing the surface of the object to be treated in the vertical direction in the middle of the transport path defined in the chamber and which is fixed to the movable plate . process and
a step of transporting the object to be processed along the transport path while moving the movable plate up and down according to the transport position of the object to be processed based on the shape of the surface to be processed to move the electrode up and down. plasma processing method.

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