TWI757506B - Plasma processing device - Google Patents

Abstract

[Problem] When a plurality of substrates are placed in parallel on the lower electrode and subjected to plasma treatment, the occurrence of abnormal discharge in the lower electrode is suppressed. [Solution] In the lower electrode (4) in which a plurality of, for example, two substrates (G) are placed in parallel, the belt-shaped members (61 to 67) constituting the ring portion (6) are arranged in the following relationship: , when viewed along the four sides of the substrate (G) in a clockwise or counterclockwise circuit, such that the side surface of the front end portion of the belt member on the rear side contacts the rear end surface of the belt member on the front side. is configured. Two strip-shaped members arranged on a straight line in the lateral direction so as to contact the rear end surface of the strip-shaped member (vertical member) (64) provided in the boundary region (44) between the two substrates (G) A gap (60) for absorbing the elongation caused by the heat of the cross member is formed between the end surfaces of the (cross member) (63, 67). Since the lower electrode (4) is not exposed from the gap (60), even if the plasma enters the gap (60), the occurrence of abnormal discharge can be suppressed.

Description

Plasma processing device

The present invention relates to a plasma processing apparatus that mounts a quadrangular substrate on a lower electrode having at least an upper side surface surrounded by a ring portion made of an insulating member over the entire circumference, and processes the substrate by plasma.

In the manufacture of flat panel displays (FPD) such as liquid crystal display devices (LCD), there is a process of supplying a plasma treatment gas to a glass substrate as a substrate to be treated, and performing plasma treatment such as etching treatment and film formation treatment. For example, plasma processing is carried out in a state where a substrate is mounted on a mounting table provided in a processing container formed in a vacuum atmosphere. The mounting table is formed, for example, in the shape of a rectangular cylinder, and an insulating ring member called a so-called focus ring or the like is provided on the outer peripheral portion thereof to distribute the plasma on the substrate with good uniformity. This ring member is a corner-shaped annular body, for example, formed by combining a plurality of members forming one side of the corner type. These members have the property of thermal expansion, so the thermal expansion members push against each other, which may cause deformation or breakage of the ring member. In addition, when a gap is formed between members, plasma enters the gap and causes abnormal discharge or erosion of the spray film formed on the surface of the mounting table.

Patent Document 1 proposes that an angle-shaped shield member is formed by four constituent elements, and the end face on one end side of one constituent element abuts on the side face of the other adjacent constituent element, and the side face on the other end side abuts and adjoins. The above-mentioned other constituent element is different from the end face of one end side of the other constituent element, and the technique of combining constituent elements in this way. In this example, even if one of the constituent elements expands due to thermal expansion, the other adjacent constituent element is not pressed, and the generation of a gap between the shield member and the lower electrode can be prevented. However, Patent Document 1 places one substrate on a stage and performs plasma treatment, and does not take into consideration when a plurality of substrates are placed in parallel on a stage and the plurality of substrates are subjected to plasma treatment at the same time.

In addition, Patent Document 2 describes that in a shadow frame for suppressing deformation of the substrate by pressing the edge of a large-area substrate such as a flat panel display against a substrate support body, a shadow frame is provided that covers the outer edge of the substrate, and a The composition of the mask panel covering the center of the . In addition, Patent Document 3 describes that when an EL material is formed by vacuum deposition on the surface of a member to be vapor-deposited such as an EL (Electro-Luminescence) display, a vapor-deposition mask is fixed to the member to be vapor-deposited for vapor deposition. In the tooling, the technology of absorbing the thermal deformation of the vapor deposition mask is formed by forming the mask expansion and contraction buffer groove in the vapor deposition tool. However, these Patent Documents 2 and 3 do not take into consideration the formation of gaps between members constituting the ring member or the suppression of abnormal discharge, and cannot solve the problem of the present invention. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Patent No. 5885939 [Patent Document 2] Patent No. 5064217 [Patent Document 3] Patent No. 4795842

[The problem to be solved by the invention]

The present invention has been made in view of such a situation, and an object of the present invention is to provide a technique capable of suppressing the occurrence of abnormal discharge in the lower electrode when a plurality of substrates are placed in parallel on the lower electrode to perform plasma processing. [means to solve the problem]

The plasma processing apparatus according to the present invention, in which a quadrangular substrate is placed on a lower electrode surrounded by a ring portion composed of an insulating member over the entire circumference at least on the side surface of the upper portion, and the substrate is processed by plasma, is characterized by: The lower electrode is configured such that a plurality of substrates are placed side by side in the lateral direction at intervals, and each substrate is placed on each ring portion, and one of the ring portions adjacent to each other is constituted by a band-shaped member, and the band-shaped member is, When viewed on a cruising path circling clockwise along the four sides of the substrate, if the cruising direction is defined as the front, the side surface of the front end portion of the belt member on the rear side contacts the rear end surface of the belt member on the front side. In the case of forming four sides in such a way that they are related to each other, the other side of the adjacent ring portions is constituted by a belt-shaped member, and the belt-shaped member is such that, when viewed on a circuit that travels counterclockwise along the four sides of the substrate, The traveling direction is defined as the front, and the four sides are formed in such a way that the side surface of the front end portion of the belt-shaped member on the rear side contacts the rear end surface of the belt-shaped member on the front side. The rear side is provided with a restricted portion for restricting the movement in the longitudinal direction, and the extension direction of the boundary region between the lower electrodes corresponding to the adjacent substrates is defined as the longitudinal direction, and the belt-shaped member provided in the boundary region is defined as the longitudinal direction. When it is defined as a vertical member, and a belt-shaped member extending in the lateral direction is defined as a horizontal member, the vertical member provided in the above-mentioned boundary area is common to each circuit system of the above-mentioned mutually adjacent ring parts, and at the front end part. A gap for absorbing elongation caused by heat of the horizontal member is formed between the lateral member belonging to one of the ring portions, the lateral members of which are in contact with the rear end face of the vertical member, and the other lateral member belonging to the ring portion.

In another aspect of the present invention, a plasma processing apparatus is configured such that a quadrangular substrate is placed on a lower electrode surrounded by a ring portion made of an insulating member over the entire circumference at least on the side surface of the upper portion, and the substrate is processed by plasma. The above-mentioned lower electrode is configured such that a plurality of substrates are placed side by side in the lateral direction at intervals, and each substrate is placed on each ring portion, and the ring portions adjacent to each other are all constituted by a band-shaped member, and the band-shaped The member is, when viewed along the four sides of the base plate, a circling path clockwise and a cruising path counterclockwise, and when the direction of the above-mentioned traversing is defined as the front, the front end of the belt-shaped member on the rear side is used. Each of the belt-shaped members constituting the above-mentioned ring portion is provided with a restricted portion for restricting movement in the longitudinal direction on the rear side thereof. The extension direction of the boundary region between the lower electrodes corresponding to the adjacent substrates is defined as the vertical direction, the strip-shaped member provided in the boundary region is defined as the vertical member, and the strip-shaped member extending in the lateral direction is defined as In the case of a horizontal member, the vertical member installed in the boundary region is composed of one vertical member and the other vertical member respectively belonging to the one circuit path and the other circuit path of the adjacent ring portions, and in the above-mentioned Between the side surface of the front end portion of one of the vertical members and the front end surface of the transverse member on the circuit path of the other ring portion facing the side surface, a space for absorbing the elongation caused by the heat of the transverse member is formed. The gap is formed between the side surface of the front end portion of the other vertical member and the front end surface of the transverse member that is opposite to the side surface and belongs to the circuit path of the one ring portion. [Inventive effect]

According to the present invention, when the ring portion is provided so that the plurality of substrates are surrounded by the side surfaces of at least the upper portion of the lower electrode placed in parallel, the belt-shaped member constituting the ring portion is tied so that one end side in the extension direction of the belt-shaped member is open. , or in such a manner that a gap for absorbing heat-induced elongation is formed between the belt-shaped members facing each other. Therefore, even if the band-shaped member is thermally expanded during the plasma treatment, the band-shaped member can be prevented from being damaged or deformed due to the pressing of the band-shaped members. In addition, the gap for absorbing the elongation caused by the heat of the belt-shaped members is formed in the region not in contact with the lower electrode, so that the lower electrode is not exposed from the gap between the belt-shaped members. Therefore, the lower electrode is not exposed. The side surface of the electrode is not directly exposed to the plasma, and the erosion of the spray film formed on the surface of the lower electrode or the generation of abnormal discharge can be suppressed. [Simple description of the drawing]

[ Fig. 1 ] A longitudinal cross-sectional side view of an embodiment of a plasma processing apparatus. [Fig. 2] A plan view showing an embodiment of the lower electrode and the ring portion provided in the plasma processing apparatus. [Fig. 3] A longitudinal cross-sectional side view showing the transverse member of the belt-shaped member constituting the ring portion. [Fig. 4] A plan view showing the lower electrode and the ring portion. [Fig. 5] A plan view showing another example of the ring portion. [Fig. 6] A plan view showing another embodiment of the ring portion. [Fig. 7] A plan view showing another embodiment of the ring portion. [Fig. 8] A plan view showing another embodiment of the ring portion.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification and the drawings, components having substantially the same configuration are denoted by the same reference numerals, and overlapping descriptions are omitted. FIG. 1 is a longitudinal cross-sectional side view showing an embodiment of a plasma processing apparatus 1 of the present invention. The plasma processing apparatus 1 is configured as a plasma processing apparatus that generates inductively coupled plasma, for example, an inductively coupled plasma processing that performs etching processing or ashing processing on a quadrangular substrate such as a G6 half substrate. G6 half-substrate means a substrate in which the length of the long side of a G6 size (1500mm×1850mm) substrate is divided into half. For example, it is suitable for an organic EL display using an organic light emitting diode (OLED: Organic Light Emitting Diode). By. Hereinafter, the G6 half-substrate is used as the substrate G for description.

The plasma processing apparatus 1 includes a rectangular-shaped, airtight processing container 10 that is electrically grounded and is made of a conductive material, for example, aluminum whose inner wall surface has been anodized. The processing chamber 10 is divided into an antenna chamber 11 and a processing chamber 12 up and down by a dielectric window 2 made of, for example, ceramics such as alumina (Al ₂ O ₃ ), or quartz or the like. A support member 13 protruding inward is provided between the side wall 111 of the antenna chamber 11 and the side wall 121 of the processing chamber 12 in the processing container 10 , and the dielectric window 2 is placed on the support member 13 . On the side surface of the processing container 10 , an unloading port 14 for transferring the plasma-processed substrate G is provided, and is configured to be freely openable/closeable by a gate valve 15 .

A gas supply portion 21 is fitted into the lower side of the dielectric window 2 . The gas supply part 21 is made of, for example, a conductive material, for example, aluminum whose inner surface or outer surface has been anodized, and is electrically grounded. A gas flow path 22 extending horizontally is formed inside the gas supply unit 21 , and a plurality of gas discharge holes 23 extending downward are communicated with the gas flow path 22 . The dielectric window 2 is provided with a gas supply pipe 24 in communication with the gas flow path 22. The gas supply pipe 24 penetrates through the outside of the processing container 10 from the patio, and is connected to a processing gas supply source, a valve system, and the like. The process gas supply system 25 is connected.

A high frequency (RF) antenna 3 is installed in the antenna chamber 11 . The high-frequency antenna portion 3 is configured by arranging an antenna 31 made of a metal with good conductivity such as copper or aluminum into an arbitrary shape such as a ring shape or a spiral shape, and is formed by a spacer 32 made of an insulating member and a dielectric material. Window 2 is installed separately. The high-frequency antenna unit 3 may be a multiple antenna including a plurality of antenna units. A power feeding member 34 extending above the antenna chamber 11 is connected to the terminal 33 of the antenna 31 .

In the lower part of the processing chamber 12, a plurality of lower electrodes 4 on which, for example, two G6 half substrates G are mounted are provided so as to face the high-frequency antenna part 3 with the dielectric window 2 interposed therebetween. The lower electrode 4 includes a first electrode body 41 and a second electrode body 42 provided below the first electrode body 41 . The first electrode body 41 and the second electrode body 42 are made of, for example, aluminum, stainless steel, or the like whose surfaces have been anodized.

The surface of the first electrode body 41 serves as a substrate placement surface. For example, as shown in FIG. 2 , it includes a first substrate placement surface 51 and a second substrate placement surface 52 so that two substrates G are placed in parallel with a gap therebetween. . These 1st board|substrate mounting surface 51 and the 2nd board|substrate mounting surface 52 are comprised so that it may fit the shape of the board|substrate G so that it may become a square shape in a planar view. As shown in FIG. 1 , for example, a recessed portion 43 is formed on the surface of the first electrode body 41 . The concave portion 43 forms the boundary region 44 between the lower electrodes 4 corresponding to the adjacent substrates G, and the surface of the first electrode body 41 is divided into two by the concave portion 43 to form two substrate placement surfaces. 51, 52. Therefore, the concave portion 43 is parallel to the long sides of the first and second substrate placement surfaces 51 and 52 , and is formed, for example, in the center portion of the long side of the first electrode body 41 .

On the upper surface and the side surface of the first electrode body 41 , including the inner surface and the bottom surface of the concave portion 43 , an insulating spray film 45 made of, for example, aluminum oxide is formed. In addition, for example, inside the spray films 45 provided on the first and second substrate mounting surfaces 51 and 52 are disposed electrodes for clamping (not shown), and the substrate G is formed by electrostatic attraction force. Keep.

The bottom of the lower electrode 4 is supported by the hollow support 47 via the insulating member 46 . The support column 47 penetrates while maintaining the bottom of the processing container 10 in an airtight state, and is connected to a lifting mechanism (not shown) disposed outside the processing container 10 . For example, at the bottom of the processing chamber 12 , substrate transfer mechanisms such as a plurality of transfer pins (not shown) are provided at positions corresponding to the first substrate mounting surface 51 and the second substrate mounting surface 52 , respectively. When the lower electrode 4 is raised and lowered, the transfer pin extends/retracts from the surface of the lower electrode 4 . Accordingly, the lower electrode 4 is driven up and down by the raising and lowering mechanism when the substrate G is carried in and out. Between the insulating member 46 and the bottom of the processing container 10, a corrugated tube 48 airtightly surrounding the support column 47 is arranged. The lower electrode 4 formed by the first electrode body 41 and the second electrode body 42 is connected to a high frequency power supply 55 through a matching device 54 through a power supply line 53 provided in a hollow support 47 . The high-frequency power supply 55 applies a high-frequency power for bias voltage to the lower electrode 4 during plasma processing.

Inside the first electrode body 41, for example, an annular cooling flow path 411 extending in the circumferential direction is provided. A heat transfer medium such as Galden (registered trademark) having a predetermined temperature is circulated and supplied to the cooling channel 411 from a cooling unit (not shown), and the processing temperature of the substrate G on the lower electrode 4 is controlled by the temperature of the heat transfer medium. In addition, on the upper surface of the first electrode body 41, the upper end of the gas supply path 412 provided inside the first electrode body 41 is opened, and a heat transfer gas such as helium (He) gas is supplied to the surface of the lower electrode 4 and the substrate G formed between the backsides.

The second electrode body 42 includes a flow path 421 that communicates with the lower end of the gas supply path 412 of the first electrode body 41 , and the flow path 421 is connected to a pipe for heat transfer gas. In addition, the exhaust port 16 on the bottom surface of the processing container 10 is connected to a vacuum exhaust mechanism 18 via an exhaust passage 17 . The vacuum evacuation mechanism 18 is connected to a pressure adjustment unit (not shown), and is configured to maintain a desired degree of vacuum in the processing chamber 10 by this.

A ring portion 6 made of an insulating member such as insulating ceramics such as alumina is disposed on the lower electrode 4 so as to surround the first and second substrate placement surfaces 51 and 52 over the entire circumference, respectively. Since the ring portion 6 is arranged so as to face the plasma generating space, the plasma is respectively concentrated on the two substrates G on the lower electrode 4 through the ring portion 6 . For example, when the ring portion 6 is mounted, the upper surface of the ring portion 6 is aligned with the first and second substrate mounting surfaces 51 and 52 , and the side surface of the upper portion of the lower electrode 4 is surrounded by the ring portion 6 over the entire circumference. The ring portion 6, as shown in FIG. 2, is formed, for example, by combining the strip-shaped members 61 to 67 of the elongated body.

FIG. 2 is a plan view of the lower electrode 4 , showing the first and second substrate placement surfaces 51 and 52 and the ring portion 6 . When viewing along the four sides of the substrate (the first substrate mounting surface 51 and the second substrate mounting surface 52 ) G on a traveling path that travels clockwise or counterclockwise, the traveling direction is defined as the front. A first circuit path 71 is formed around the first board mounting surface 51 in a counterclockwise circuit, and along the first circuit path 71, the belt-shaped members 61 to 64 become the side surfaces of the front end portions of the belt-shaped members on the rear side. It is arranged so as to contact the relationship between the rear end faces of the belt-shaped member on the front side. In addition, a second traveling path 72 that travels clockwise is formed around the second substrate placement surface 52, and along the second traveling path 72, the belt-shaped members 64 to 67 become the front end portions of the belt-shaped members on the rear side. It is arranged in such a way that the side surface of the belt contacts the rear end surface of the belt-shaped member on the front side.

The band-shaped member 64 is arranged in the recessed portion 43 forming the boundary region 44 of the lower electrode 4 . The recessed portion 43 and the band-shaped member 64 are arranged so that the plasma does not enter the gap between the recessed portion 43 and the band-shaped member 64 when the band-shaped member 64 is arranged in the recessed portion 43 , and the height position of the surface of the band-shaped member 64 The first and second substrate placement surfaces 51 and 52 are formed in accordance with their shapes so that they are aligned with each other.

These belt-shaped members 61 to 67 expand in the longitudinal direction due to thermal expansion due to heat, and therefore, are provided on the rear side of the belt-shaped members 61 to 67 that restrict movement in the longitudinal direction. Among the both end portions of the belt-shaped members 61 to 67 , the front side in the extension direction is referred to as one end side, and the rear portion side in which the restricted portion is provided is referred to as the other end side. The other end side is defined as the restricting ends 611 , 621 , 631 , 641 , 651 , 661 , and 671 , and the one end side is defined as the free ends 612 , 622 , 632 , 642 , 652 , 662 , and 672 . In addition, let the belt-shaped member 64 provided in the border region 44 be the vertical member 64 , the extension direction of the vertical member 64 be the vertical direction, and the side-adjacent belt-shaped member at the restriction end 641 of the vertical member 64 63 and 67 are made into the horizontal members 63 and 67, and the extension direction of the horizontal members 63 and 67 is made into a horizontal direction.

In this way, among the belt-shaped members 61 to 64 forming the first traveling path 71 , the respective end surfaces of the restricting ends 611 to 641 of the belt-shaped members 61 to 64 are adjacent to the free ends 612 of the other belt-shaped members 61 to 64 . In a state where the side surfaces of ~642 are in contact with each other, the band-shaped members adjacent to each other are arranged so as to be perpendicular to each other. In addition, in the belt-shaped members 64 to 67 forming the second traveling path 72 , the respective end surfaces of the restricting ends 641 to 671 of the belt-shaped members 64 to 67 are adjacent to the free ends 642 to 67 of the other belt-shaped members 64 to 67 . In a state where the side surfaces of 672 are in contact with each other, the band-shaped members adjacent to each other are arranged so as to be perpendicular to each other. In the configuration in which the border regions 44 of the adjacent ring portions 6 include the common vertical members 64 like the ring portions 6 of this configuration, the directions of the loops of the mutually adjacent ring portions are opposite to each other.

The transverse member 63 provided in the first circuit path 71 and the transverse member 67 provided in the second circuit path 72 are arranged on a straight line. The end faces (free ends) 632 of the cross members 63 and the end faces (free ends) 672 of the cross members 67 are opposed to each other, and between the end faces is used to absorb the elongation caused by the heat of the cross members 63 and 67 . The gap 60 is formed on the extension line of the boundary area 44 . In this example, the vertical member 64 provided in the boundary area 44 is common to each of the first circuit path 71 and the second circuit path 72 . are arranged opposite to each other. The gap 60 is formed on the extension line of the boundary area 44 , which means that the gap 60 is formed within the range of the width of the limiting end 641 of the vertical member 64 . The width A of the gap 60 is formed in consideration of the elongation caused by the heat of the cross members 63 and 67 .

FIG. 3 shows a longitudinal cross-sectional side view of the transverse members 63 and 67 in the vicinity of the gap 60 . As shown in this figure, the end surfaces 632 and 672 of the cross members 63 and 67 which face each other are formed with step portions, respectively, and the respective step portions are combined to form a structure. Specifically, the end face 632 of the cross member 63 is configured such that the upper portion 633 protrudes from the cross member 67 side, and the end face 672 of the cross member 67 is configured such that the lower portion 673 protrudes from the cross member 63 side. They are combined with each other so that the upper end portion 633 of the end surface of the cross member 63 is positioned above the lower end surface portion 673 of the cross member 67 . A gap 60 is formed in the opposing portions of the end surfaces 632 and 672 of the cross members 63 and 67, respectively. Therefore, when viewed from the upper side, on the lower side of the gap 60 between the transverse member 63 and the transverse member 67, there is a lower portion 673 of the end surface of the transverse member 67, and the surface that becomes the structure does not appear from the lower side of the transverse members 63 and 67. exposed state.

A side insulating member 73 is arranged around the first electrode body 41 and the second electrode body 42 and on the lower side of the ring portion 6 so as to cover the side surfaces of the first electrode body 41 and the second electrode body 42 . The side insulating member 73 is formed into a ring shape having a quadrangular shape in a plan view, for example, by insulating ceramics such as alumina or insulating resin such as polytetrafluoroethylene. In addition, around the side insulating member 73 , an outer ring portion 74 that covers the side surface of the side insulating member 73 and is located at the outermost side of the side portion of the lower electrode 4 is disposed. The outer ring portion 74 is formed of, for example, the same material as the ring portion 6 in a quadrangular ring shape in plan view, and the rear side peripheral portion of the ring portion 6 is placed on the surface of the outer ring portion 74 . The lower surfaces of the side insulating members 73 are supported by the insulating members 46 . In FIG. 1, 49 is an O-ring which forms a sealing member.

Next, the attachment structure of the ring portion 6 will be described with reference to FIG. 2 . The belt-shaped members 61 to 67 have holes 75 for restriction provided at the respective restriction ends 611 to 671 , and holes 76 for support provided in front of the holes 75 for restriction and spaced apart in the longitudinal direction. At least one hole 76 for support is provided, but two or more may be provided corresponding to the lengths of the belt-shaped members 61 to 67 . The hole portion 75 for restriction functions as a restricted portion that restricts movement of the restriction ends 611 to 671 of the belt-shaped members 61 to 67 in the longitudinal direction, and for example, there are few gaps in the cross section perpendicular to the hole portion 75 for restriction. , the shape on the plane is formed as a perfect circle.

The hole portion 76 for support functions as a guided portion for guiding the free ends 612 to 672 of the belt-shaped members 61 to 67 to be freely displaced in the longitudinal direction. The cross section has a slit in the longitudinal direction, and the shape on the plane is a rectangle whose both ends are semicircles. The long diameter of the support hole 76 is formed so that even if the belt members 61 to 67 thermally expand, a support pin, which will be described later, fitted into the support hole 76 does not limit the degree of thermal expansion of the belt members 61 to 67 . of length.

The restricting ends 611 to 671 of the belt-shaped members 61 to 67 are respectively fixed to, for example, the upper surface of the side insulating member 73 or the upper surface of the first electrode body 41 by the restricting pins 77 fitted into the restricting holes 75 . . In addition, the belt-shaped members 61 to 67 are supported by the support pins 78 inserted into the supporting holes 76 so that the free ends 612 to 672 of the respective belt-shaped members are supported relative to the upper surface or the upper surface of the side insulating member 73 . The upper surface of the first electrode body 41 can be freely displaced. Accordingly, each of the belt-shaped members 61 to 67 is supported so as to be thermally expandable or thermally shrinkable along the longitudinal direction starting from the restricting ends 611 to 671 . It is also possible to provide an insulating covering member (not shown) on the upper portion of the hole portion 75 for restriction and the hole portion 76 for support, so that the restriction pin 77, the support pin 78, and the holes 75 and 76 are not arranged. exposed to plasma. Moreover, the hole 75 for restriction and the hole 76 for support are provided as countersunk holes on the back side of each of the belt-shaped members 61 to 67 , and the restriction pin 77 and the support pin 78 are provided on the side of the side insulating member 73 . Alternatively, on the first electrode body 41 side, the restriction pin 77 , the support pin 78 , and the hole portions 75 and 76 may be configured so that they are not exposed to the plasma.

The plasma processing apparatus 1 is provided with the control part 100 which consists of a computer, for example. The control unit 100 includes a program, a memory, a data processing unit composed of a CPU, and the like. The program incorporates commands. The control unit 100 can transmit control signals to the various units of the plasma processing apparatus 1, and perform the steps described later to control the substrate G. Plasma treatment was performed. The program is stored in a memory unit (not shown) of a computer storage medium such as a floppy disk, an optical disk, and a MO (Optical Magnetic Disk), and is installed in the control unit 100 .

In the plasma processing apparatus 1 described above, first, the gate valve 15 is opened, and two substrates G are held in the processing chamber 12 by a transfer mechanism not shown, for example, laterally held in parallel, and the lower electrode 4 is moved up and down, and placed on the first substrate. The surface 51 and the second substrate placement surface 52 are simultaneously placed on the first substrate placement surface 51 and the second substrate placement surface 52 by means of a substrate transfer mechanism (not shown), so that these substrates G are placed on the first substrate placement surface 51 and the second substrate placement surface 52 at the same time. It is electrostatically attracted to the lower electrode 4 . It is also possible to carry in the substrates G one by one and place the substrates G one by one on the first substrate placement surface 51 and the second substrate placement surface 52 by an external conveyance mechanism. Next, the gate valve 15 is closed, the process gas is supplied into the process chamber 12 from the process gas supply system 25 through the gas discharge hole 23 of the gas supply part 21 , and the process gas is supplied from the exhaust port 16 through the exhaust passage 17 by the vacuum exhaust mechanism 18. The inside of the processing chamber 12 is evacuated, and the inside of the processing chamber 12 is maintained at a pressure atmosphere of, for example, about 0.66 to 26.6 Pa. In addition, in order to avoid the temperature rise or temperature change of the substrate G, He gas is supplied to the back surface side of the substrate G via the gas supply path 412 .

Next, a high frequency of, for example, 13.56 MHz is applied from the high frequency power supply 37 to the high frequency antenna portion 3 , whereby a uniform induced electric field is formed in the processing chamber 12 through the dielectric window 2 , and the induced electric field is In the processing chamber 12, a high-density inductively coupled plasma in which the processing gas is plasmatized is generated. By this plasma, plasma processing is performed on two substrates G, for example, a predetermined film of the substrate G is plasma-etched at the same time. At this time, a high-frequency power having a frequency of, for example, 6 MHz is applied from the high-frequency power supply 55 to the lower electrode 4 as a high-frequency power for a bias voltage, thereby attracting ions in the plasma generated in the processing chamber 12 to the lower portion. On the electrode 4 side, etching treatment with high verticality is performed. In addition, by the ring portion 6 formed of an insulating member provided around the substrate G, the plasma is concentrated on the substrate G, and the etching rate can be increased.

The ring portion 6 is heated by being exposed to the plasma, and as shown in the schematic view of FIG. 4 , the band-shaped members 61 to 67 constituting the ring portion 6 thermally expand and elongate in the longitudinal direction. In FIG. 4 , the belt members 61 to 67 are extended in the direction of the free ends 612 to 672 with the restraint pins 77 that restrain the restraint ends 611 to 671 as a starting point, and the distal ends of the free ends 612 to 672 are displaced by the lengths due to thermal expansion. comparable size. In addition, although the end faces 632 and 672 of the cross members 63 and 67 facing each other are elongated so as to approach each other, a gap 60 is formed between these extension directions, so that the elongation caused by heat is absorbed by the gap 60 .

In this way, among the belt-shaped members 61 to 67 constituting the ring portion 6, one end side (free ends 612 to 672) in the direction of elongation during thermal expansion is open, and between the transverse members 63 and 67 facing each other, a space for absorption is formed. Gap 60 for thermally induced elongation. Therefore, even if the belt-shaped members 61 to 67 thermally expand during the plasma treatment, the adjacent belt-shaped members 61 to 67 are not pressed against each other to generate stress, and the ring portion 6 is not deformed or damaged.

In addition, the gap 60 between the cross members 63 and 67 is provided on the extension of the border region 44 , and is formed in a region not in contact with the lower electrode 4 . Therefore, when viewed from the gap 60, the rear end surface (restriction end) 641 of the vertical member 64 exists on the lower electrode 4 side, and the lower electrode 4 is not exposed. Therefore, even if the plasma enters the gap 60 at the start of the plasma treatment, It is also possible to suppress the direct exposure of the side surface of the lower electrode 4 to the plasma. As a result, the electric field generated by the plasma can be prevented from concentrating on the corner between the upper surface and the side surface of the lower electrode 4 , abnormal discharge caused by the lower electrode 4 , erosion of the spray film 45 on the surface of the lower electrode 4 , and the spray film 45 can be suppressed. Insulation cannot be maintained, and the risk of abnormal discharge increases. In addition, since the end faces 632 and 672 of the transverse members 63 and 67 facing each other are formed by combining the segments, there is one of the transverse members on the lower side of the gap 60 . Even if the plasma enters the gap 60 , the electric current can be suppressed. Contact between the slurry and the side insulating member 73 on the lower side.

Here, as shown in FIG. 5, the example in which the belt-shaped members 681-685 which comprise the ring part 68 are arrange|positioned is demonstrated. The belt-shaped members 681 to 684 provided so as to surround the entire circumference of the side surface of the upper part of the lower electrode 4 are in contact with the side surface of the front end portion of the belt-shaped member that becomes the rear side when viewed on the circuit that travels counterclockwise. The belt-shaped member on the front side is arranged so as to have a relationship between the rear end faces. A hole for restriction (not shown) and a restriction pin 691 are provided on the rear side (restriction end side) of the band-shaped members 681 to 684 , and a support pin 691 is provided at a position separated from the restriction pin 691 in the longitudinal direction. The hole portion 692 and the support pin 693 are configured so that the free end sides of the belt-shaped members 681 to 684 expand when thermally expanded. In addition, the restricting end of the belt-shaped member 685 arranged in the boundary region 44 is in contact with the side surface of the central region of the belt-shaped member 683, and a space for absorbing the belt-shaped member 685 is formed between the free end and the side surface of the belt-shaped member 681. Gap 69 based on thermal elongation.

In such a configuration, when viewed from the gap 69 , the lower electrode 4 constituting the first substrate placement surface 51 and the lower electrode 4 constituting the second substrate placement surface 52 exist on the side of the gap 69 . Therefore, when the plasma enters the gap 69, the plasma contacts the lower electrode 4, and there is a high risk that abnormal discharge of the lower electrode 4 or erosion of the spray film 45 occurs.

On the other hand, according to the above-described embodiment, when the ring portion 6 is provided so as to surround the side surface of the upper portion of the lower electrode 4 on which the two substrates G are placed, even the belt-shaped members 61 to 6 constituting the ring portion 6 during plasma processing Even in the case of thermal expansion, deformation or breakage of the ring portion 6 can be suppressed. In addition, the gap 60 formed in advance in order to absorb elongation caused by heat is configured so that the lower electrode 4 is not exposed at a position not in contact with the lower electrode 4, so that abnormal discharge of the lower electrode 4 due to plasma can be prevented. , or the generation of erosion of the spray film 45 .

Next, the ring portion 8 of another embodiment will be described with reference to FIG. 6 . The ring portion 8 is formed by combining the belt-shaped members 81 to 84 provided along the four sides of the first substrate placement region 501 and the belt-shaped members 85 to 88 provided along the four sides of the second substrate placement region 502 . The belt-shaped members 81 to 84 are arranged in such a manner that the side surfaces of the leading end portions of the rear-side belt-shaped members contact the rear end surface of the front-side belt-shaped members when viewed on the circuit path 711 that travels counterclockwise. The belt-shaped members 85 to 88 are arranged in such a manner that the side surfaces of the front end portions of the rear-side belt-shaped members contact the rear end surface of the front-side belt-shaped members when viewed on the circuit path 712 that travels counterclockwise. .

The belt-shaped member (vertical member) installed in the boundary region of the first and second substrate placement regions 501 and 502 is composed of a first vertical member 84 and a second vertical member 86 which belong to the traversing paths 711 and 712 adjacent to each other, respectively. constitute. Moreover, the 1st vertical member 84 is arrange|positioned between the belt-shaped members (horizontal members) 81 and 85 which belong to the circuit paths 711 and 712 and are arrange|positioned on a straight line, respectively. Between the end surface (free end) of the cross member 85 and the side surface of the front end portion of the first vertical member 84, a first gap 891 for absorbing the elongation caused by the heat of the cross member 85 is formed.

Moreover, the 2nd vertical member 86 is arrange|positioned between the belt-shaped members (horizontal members) 83 and 87 which belong to the circuit paths 711 and 712 and are arrange|positioned on a straight line, respectively. Between the end surface (free end) of the cross member 83 and the side surface of the front end portion of the second vertical member 86 is a second gap 892 for absorbing elongation caused by the heat of the cross member 83 . The first and second gaps 891 and 892 are formed on the extension line of the boundary region, and the lower electrodes 4 are not exposed when viewed from the side of the first and second gaps 891 and 892 .

On the rear side of each of the belt-shaped members 81 to 88 are provided a restriction hole portion (not shown) for forming each restricted portion and a restriction pin 801 , and on the front side of the restriction pin 801 are respectively provided with The supporting hole 802 and the supporting pin 803 of the lead portion are provided. The restriction hole portion, the restriction pin 801, the support hole portion 802, and the support pin 803 have the same configuration as in the above-described embodiment. Each of the belt-shaped members 81 to 88 is configured so that the free end side is extended by heat in a state where the movement in the longitudinal direction is restricted by the restriction pin 801 . Like the ring portions of this configuration, in the configuration in which vertical members are provided corresponding to each ring portion in the boundary region of the ring portions 8 adjacent to each other, the directions in which the ring portions adjacent to each other travel are the same direction.

In such a configuration, when the ring portion 8 is provided so as to surround the side surface of the upper portion of the lower electrode 4 on which the two substrates G are placed, even if the band-shaped members 81 to 88 constituting the ring portion 8 are thermally expanded during plasma treatment In this case, deformation or breakage of the ring portion 8 can also be suppressed. In addition, the gaps 891 and 892 formed in advance to absorb elongation caused by heat are formed at positions not in contact with the lower electrode 4 so that the lower electrode 4 is not exposed, so that the lower electrode 4 can be prevented from being caused by plasma. abnormal discharge or erosion. In addition, in this example, when the first and second vertical members 84 and 86 are integrally formed, the direction of extension of the integrally formed member on the side of the first substrate placement region 501 and the side of the second substrate placement region 502 are opposite to each other. , there is a possibility that the vertical member may be cracked in the portion in contact with the restriction pin 801 .

As described above, the present invention is also applicable to the case where three or more substrates are placed on the lower electrode 4 with an interval therebetween. As shown in FIG. 7 , first to third substrate placement regions 511 , 512 , and 513 are formed on the surface of the lower electrode 4 , and common vertical members are arranged in the boundary regions provided between the respective substrate placement regions. example. A counterclockwise traveling path is formed around the first substrate placement area 511 , and along the traveling path, the side surfaces of the leading end portions of the rear-side belt-shaped members are arranged in such a relationship that the side surfaces of the front-side belt-shaped members contact the rear end surfaces of the front-side belt-shaped members. There are belt-shaped members 910 to 913 . A clockwise travel path is formed around the second substrate placement area 512, and along the travel path, the side surfaces of the front end portions of the rear-side belt-shaped members are arranged in such a relationship that the side surfaces of the front-side belt-shaped members contact the rear end surfaces of the front-side belt-shaped members. There are belt-shaped members 913 to 916 . A counterclockwise circuit is formed around the third substrate placement area 513, and along the circuit, the side surfaces of the leading end portions of the rear belt-shaped members are arranged in such a relationship that the rear end surfaces of the front belt-shaped members are in contact with each other. There are belt-shaped members 915, 917 to 919.

The vertical members 913 and 915 are shared by each of the adjacent circuit paths, respectively. In the configuration in which a common vertical member is provided in the boundary region of the adjacent ring portions like the ring portions of this configuration, the directions of the loops of the mutually adjacent ring portions are opposite to each other. In addition, between the horizontal member 912 and the horizontal member 916 arranged on the straight line, and between the horizontal member 914 and the horizontal member 919 arranged on the straight line, there are respectively formed first for absorbing the elongation caused by the heat of the horizontal member. gap 921 and second gap 922 . The first and second gaps 921 and 922 are formed on the extension lines of the boundary regions, respectively, so that the lower electrode 4 is not exposed from the first and second gaps 921 and 922 . On the rear side of each of the belt-shaped members 910 to 919 , a restriction hole portion (not shown) and a restriction pin 923 constituting each restricted portion are provided. Further, on the front side of the restraining pin 923, there are provided supporting holes 924 and supporting pins 925 that constitute each guided portion, and the respective belt-shaped members 910 to 919 are regulated by the restraining pins 923 while the movement in the longitudinal direction is regulated. In this state, the free end side is extended due to heat.

In the first gap 921 and the second gap 922 in this example, similarly to the gap 60 of the above-described embodiment, the respective segments of the mutually opposing end surfaces of the cross members 912 and 916 and the cross members 914 and 919 are respectively composition to form. In this way, when the first gap 921 and the second gap 922 are viewed from above, the surfaces of the structures located on the lower side of the cross members 912 and 916 and the cross members 914 and 919 are not exposed.

8, the first to third substrate placement regions 511, 512, and 513 are formed on the surface of the lower electrode 4, and when border regions are provided between the substrate placement regions, the border regions are arranged in the respective border regions. An example in which a first vertical member and a second vertical member are provided. Counterclockwise traveling paths are respectively formed around the first to third substrate placement regions 511 to 513 , and along the traveling paths, the side surfaces that become the front ends of the rear belt-shaped members respectively contact the front-side belt-shaped members. In the form of the relationship between the end faces, the belt-shaped members 931 to 934 , the belt-shaped members 941 to 944 , and the belt-shaped members 951 to 954 are arranged.

A first vertical member 934 and a second vertical member 942 are provided in the boundary region between the first and second substrate placement regions 511 and 512, and the first vertical member 931 and the horizontal member 941 are arranged in a straight line between the horizontal member 931 and the horizontal member 941. Longitudinal member 934. A gap 961 is formed between the end surface (free end) of the horizontal member 941 and the first vertical member 934 . Similarly, the 2nd vertical member 942 is arrange|positioned between the horizontal member 933 and the horizontal member 943 arrange|positioned on a straight line. A gap 962 is formed between the end surface (free end) of the horizontal member 933 and the second vertical member 942 . These gaps 961 and 962 are for absorbing the elongation caused by the heat of the cross member, and are provided on the extension line of the boundary region.

Moreover, the 1st vertical member 944 and the 2nd vertical member 952 are provided in the boundary area|region of the 2nd and 3rd board|substrate mounting area|region 512,513. Moreover, the 1st vertical member 944 is arrange|positioned between the horizontal member 941 and the horizontal member 951 arrange|positioned in a straight line. A gap 963 is formed between the end surface (free end) of the horizontal member 951 and the first vertical member 944 . Similarly, the 2nd vertical member 952 is arrange|positioned between the horizontal member 943 and the horizontal member 953 arrange|positioned in a straight line. A gap 964 is formed between the end surface (free end) of the horizontal member 943 and the second vertical member 952 . These gaps 963 and 964 are for absorbing the elongation caused by the heat of the cross member, and are provided on the extension line of the boundary region.

Like the ring portions of this configuration, in the configuration in which vertical members are provided corresponding to each ring portion in the boundary region of the ring portions 8 adjacent to each other, the directions in which the ring portions adjacent to each other travel are the same direction as each other. On the rear side of each belt-shaped member, a restriction hole portion (not shown) and a restriction pin 971 constituting each restricted portion are provided. Further, on the front side of the restricting pin 971, a supporting hole 972 and a supporting pin 973 constituting the guided portion are provided, and each band-shaped member is in a state where the movement in the longitudinal direction is restricted by the restricting pin 971. The free end side is elongated by heat.

In the configuration shown in FIGS. 7 and 8 , gaps 961 to 964 are formed in advance to absorb the elongation caused by the heat of the cross member in order to suppress the contact between the band-shaped members constituting the ring portion due to thermal expansion during the plasma treatment. , is provided in a region not exposed from the lower electrode 4 , so that the occurrence of abnormal discharge or erosion of the lower electrode 4 can be suppressed.

In the present embodiment, the ring portion is made of insulating ceramics, for example, alumina, yttrium, silicon nitride, quartz, or the like. Also, as the pins, stainless steel pins, ceramic pins, aluminum pins, or the like can be used. In addition, pins are used for the restriction of the movement in the longitudinal direction of the belt-shaped member, but other than the pins, for fixing the rear end of the belt-shaped member, for example, screwing, crimping by a jig, etc., or a belt may be used. Fixing of the fitting structure of the shaped member and the side insulating member, etc. In addition, as for the free-displacement portion on the free end side, a guide member or the like that can restrict displacement in one direction by a fitting-type rail or the like between the belt-shaped member and the side insulating member can be used.

Here, the method of arranging the lower electrode 4 on the bottom of the processing chamber 12 is not limited to the arrangement through the insulating member 46 supported by the vertical support 47 as shown in FIG. 1 . For example, on the bottom surface of the processing chamber 12 formed of the processing container 10 made of metal, a support table formed of an insulating member may be fixedly arranged, and the lower electrode 4 may be provided thereon. In this case, the transfer of the substrate G to the external transfer mechanism is performed using a substrate transfer mechanism provided with a drive mechanism, and the drive mechanism allows the first and second substrate placement surfaces 51 and 52 to be extended. /Retracted handover pin lift.

In addition, the plasma formed in the processing container 10 is not limited to the case where the high-frequency antenna portion 3 and the dielectric window 2 for forming the inductively coupled plasma are provided. It is also applicable to the case where the high-frequency antenna portion 3 is provided through a metal wall (metal window) made of a non-magnetic metal such as aluminum or aluminum alloy instead of the dielectric window 2 . In this case, the process gas is supplied not by the gas supply unit 21 but by providing a gas shower mechanism on the metal wall. Alternatively, a configuration in which a capacitively coupled plasma is formed between the lower electrode 4 and a metal gas supply portion may be used.

The type of plasma treatment performed using the plasma treatment apparatus of the present invention is not limited to the etching treatment or ashing treatment described above, and may be a film formation treatment on the substrate G. In addition, the type of the substrate G is not limited to the example of the G6 half substrate described above, and a rectangular substrate of other size may be used. In addition, it is not limited to the rectangular substrate for FPD, and it is applicable also to the rectangular substrate of other uses, such as processing a solar cell.

4‧‧‧Lower electrode 25‧‧‧Processing gas supply system 44‧‧‧Boundary region 51‧‧‧First substrate mounting surface 52‧‧‧Second substrate mounting surface 6‧‧‧Ring part 60‧‧‧ Gap 61~63: 65~67‧‧‧Strip member (horizontal member) 64‧‧‧Strip member (vertical member) 611: 621: 631: 641: 651: 661: 671‧‧‧limiting end 612: 622 : 632: 642: 652: 662: 672‧‧‧Free end 71‧‧‧First circuit path 72‧‧‧Second circuit path 75‧‧‧Restriction hole 76‧‧‧Support hole 77 ‧‧‧Restriction pin 78‧‧‧Support pin 100‧‧‧Control part A‧‧‧Width of gap 60

4‧‧‧Lower electrode

44‧‧‧Boundary area

51‧‧‧First board mounting surface

52‧‧‧Second board mounting surface

6‧‧‧Ring

60‧‧‧clearance

61~63: 65~67‧‧‧Strip member (cross member)

64‧‧‧Strip member (longitudinal member)

611:621:631:641:651:661:671‧‧‧limited end

612:622:632:642:652:662:672‧‧‧Free end

71‧‧‧Route 1

72‧‧‧Route 2

75‧‧‧Hole for restriction

76‧‧‧Hole for support

77‧‧‧Restricted Pins

78‧‧‧Support pins

A‧‧‧Width of gap 60

Claims (3)

A plasma processing apparatus in which a quadrangular substrate is placed on a lower electrode surrounded by a ring portion formed of an insulating member over the entire circumference at least on the side surface of the upper portion, and the substrate is processed by plasma, wherein the lower portion is characterized in that: The electrodes are configured such that a plurality of substrates are placed side by side in the lateral direction at intervals, and each substrate is placed on each ring portion, and one of the ring portions adjacent to each other is constituted by a band-shaped member, and the band-shaped member is formed along the edge. When viewed on a cruising path circling clockwise with respect to the four sides of the substrate, if the above-mentioned cruising direction is defined as the front, such that the side surface of the front end portion of the rear band member contacts the rear end face of the front band member. In the case where four sides are formed by the method, the other side of the adjacent ring portions is constituted by a belt-shaped member, and the belt-shaped member is such that, when viewed on a circuit that travels counterclockwise along the four sides of the substrate, if the circuit is The direction is defined as the front, and the four sides are formed in such a way that the side surface of the front end portion of the belt-shaped member on the rear side contacts the rear end surface of the belt-shaped member on the front side. The side is provided with a restricted portion for restricting the movement in the longitudinal direction, and the extension direction of the border region between the lower electrodes corresponding to the adjacent substrates is defined as the longitudinal direction, and the band-shaped member provided in the border region is defined as When the vertical member is defined as a horizontal member extending along the horizontal direction, the vertical member provided in the boundary area is common to the respective circuit systems of the adjacent ring portions, and the side surfaces of the front end portion are respectively A gap for absorbing elongation caused by heat of the horizontal member is formed between the horizontal member belonging to one of the ring portions that is in contact with the rear end surface of the vertical member, and the horizontal member belonging to the other side of the ring portion. A plasma processing apparatus in which a quadrangular substrate is placed on a lower electrode surrounded by a ring portion formed of an insulating member over the entire circumference at least on the side surface of the upper portion, and the substrate is processed by plasma, wherein the lower portion is characterized in that: The electrodes are configured such that a plurality of substrates are placed side by side in the lateral direction at intervals, and each substrate is placed on each ring portion, and the ring portions adjacent to each other are all constituted by a band-shaped member, and the band-shaped member is formed along the substrate. When looking at one of the four sides of the clockwise circuit and the counterclockwise circuit, if the direction of the above circuit is defined as the front, the side surface of the front end of the belt-shaped member that becomes the rear side is in contact with the front side. Each of the belt-shaped members constituting the above-mentioned ring portion is provided with a restricted portion for restricting the movement in the longitudinal direction at the rear side thereof, and the substrates adjacent to each other are corresponding to each other. The extension direction of the border region between the lower electrodes is defined as the vertical direction, the strip-shaped member provided in the above-mentioned border region is defined as the vertical member, and the strip-shaped member extending in the lateral direction is defined as the horizontal member, and provided in the The vertical members of the border region are composed of one of the one and the other of the loops adjacent to each other and the other of the loops, respectively, and the front end of the one of the vertical members. Between the side surface of the part and the front end surface of the cross member on the circuit path of the ring part that is opposite to the side surface and belongs to the other side, a gap is formed for absorbing the elongation caused by the heat of the cross member. In the other side The gap is formed between the side surface of the front end portion of the vertical member and the front end surface of the transverse member on the circuit path of the one ring portion which is opposed to the side surface. The plasma processing apparatus according to claim 1 or 2, wherein a guided portion for guiding the belt-shaped member in the longitudinal direction is provided on the front side of the belt-shaped member relative to the restricted portion.

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