TWI754077B - Plasma processing device - Google Patents

Abstract

[Problem] To provide a plasma processing apparatus capable of suppressing the influence on surrounding members caused by applying high-frequency power to the electrode portion on which the substrates are placed when plasma processing is performed simultaneously on a plurality of substrates to be processed. [Solution] In the plasma processing apparatus (1), the processing gas supplied to the processing space is converted into a plasma by the plasma forming part (31), and the first electrode part (41a) for applying high-frequency power is constituted for carrying A first substrate placement surface (51) of the substrate to be processed (G) is placed. Furthermore, the second electrode portion (41b) made of metal to which high-frequency power is applied is provided at a position spaced apart from and adjacent to the first electrode portion (41a), and constitutes a second electrode portion for placing other substrates to be processed. A substrate placement surface (52). A ring portion made of ceramics is provided at a position surrounding both the peripheries of the first and second substrate placement surfaces (51, 52), and a dielectric member ( 44), the dielectric member (44) is composed of a dielectric with a lower dielectric constant than the above-mentioned ceramic.

Description

Plasma processing device

The present invention relates to a technique for performing plasma processing by supplying a processing gas to be plasmatized to a substrate to be processed.

In the manufacture of flat-panel displays (FPDs) such as liquid crystal display devices (LCDs), there is a process of supplying a process gas for plasmaization to a glass substrate, which is a substrate to be processed, and performing plasma treatment such as etching treatment or film formation treatment. . For example, the plasma processing is performed in a state where the substrate is mounted on a mounting table provided in a processing container in which a vacuum atmosphere is formed.

For example, in Patent Document 1, it is described that a groove extending vertically and horizontally is formed on the surface of an electrode plate disposed in a vacuum chamber, and an insulating member is disposed in the groove, so that the substrates are respectively disposed in the grooves surrounded by the insulating member. A plasma processing apparatus that performs etching processing on the surfaces of a plurality of electrode plates together with a plurality of substrates. Furthermore, Patent Documents 2 and 3 describe a technique of arranging various dielectric materials around the electrodes when a plurality of substrates are placed on the electrodes to perform plasma processing (in Patent Document 2, an aluminum surrounding substrate mounting table is described). The dielectric ring or the first and second dielectric caps of the convex portion. In Patent Document 3, the base electrode is a dielectric plate arranged on the upper surface of the metal plate, or the substrate is transported to the dielectric plate. A ceramic tray on a quality plate.

However, in any one of Patent Documents 1 to 3, when plasma processing is performed in a state where a plurality of substrates to be processed are arranged adjacent to each other, the pair of high-frequency power applied to each electrode member is arranged on these substrates. The influence of the components around the substrate to be processed and its countermeasures have not been discussed. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 5094307: Paragraphs 0011 to 0015, Figure 1, Figure 2 [Patent Document 2] Japanese Patent Publication No. 7-30468: Column 6, Line 39 to Column 7, No. 12 Line, Figure 1 [Patent Document 3] Japanese Patent No. 4361045: Paragraphs 0028, 0029, Figure 1, Figure 3

[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, when plasma processing is performed on a plurality of substrates to be processed at the same time, that the application of high-frequency power to the electrode portion on which the substrates to be processed is placed can be suppressed to cause damage to surrounding members. The effect of the plasma processing device. [means to solve the problem]

A plasma processing apparatus according to the present invention performs plasma processing on a substrate to be processed according to a processing gas to be plasmatized, and the plasma processing apparatus is characterized by comprising: a processing container configured to perform the above-mentioned plasma processing. space, and is connected to a process gas supply part for supplying process gas to the process space, and a vacuum evacuation part for vacuum evacuation of the process space; a plasma forming part, which is to be supplied to the process space for processing The gas is plasmatized; The first electrode part made of metal is provided in the above-mentioned processing space, and the upper surface thereof constitutes a first substrate mounting surface for mounting a substrate to be processed, and high-frequency power is applied; Metal; The second electrode portion made by the manufacturer is arranged at a position spaced apart from and adjacent to the first electrode portion in the processing space, and the upper surface thereof is configured to mount other substrates to be processed that are different from the one to be processed. The second substrate mounting surface of the second substrate is applied, and high-frequency power is applied; a ceramic ring portion, viewed from the upper side, surrounds both the periphery of the first substrate mounting surface and the periphery of the second substrate mounting surface; and a dielectric member, which is provided on the lower surface side of the ring portion located between the first and second substrate placement surfaces, and is formed of a dielectric having a lower permittivity than the ceramic. [Inventive effect]

According to the present invention, around the first substrate placement surface on the upper surface side of the first electrode portion and around the second electrode portion provided at a position spaced apart from and adjacent to the first electrode portion Among the ceramic ring portions provided on both sides of the periphery of the second substrate placement surface on the upper surface side, the lower surface side of the ring portion located between the first and second substrate placement surfaces has a higher dielectric constant. The above-mentioned ceramic dielectric member having a low dielectric constant can reduce the influence of the electric field strength acting on the ring portion at the position.

Hereinafter, the configuration of the plasma processing apparatus 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 3 . The plasma processing apparatus 1 of this example generates inductively coupled plasma, and performs plasma processing of inductively coupled plasma such as etching processing or ashing processing on a rectangular substrate to be processed, such as a G6 half substrate. The G6 half substrate is a substrate in which the length of the long side of the G6 size (1500mm×1850mm) substrate is divided into half, for example, it is suitable for organic EL displays using organic light emitting diodes (OLED: Organic Light Emitting Diode). In the following description, this G6 half-substrate is referred to as a substrate G.

The plasma processing apparatus 1 of this example is provided with a conductive material, for example, an airtight processing container 10 in the shape of a square tube which is electrically grounded and is made of aluminum whose inner wall surface is anodized. The processing container 10 is divided into upper and lower sections in the antenna chamber 11 and the processing space 12 by a dielectric window 2 made of ceramics such as alumina (Al ₂ O ₃ ), quartz, or the like.

Between the side wall 111 of the antenna chamber 11 of the processing container 10 and the side wall 121 of the processing space 12 , there is provided a support member 13 protruding from the inside, and the dielectric window 2 is placed on the support member 13 . On the side surface of the processing container 10, when the substrate G to be plasma-processed is received and delivered, the inlet/outlet port 14 for opening and closing the gate valve 15 is provided.

On the lower surface side of the dielectric window 2, a gas supply portion 21 is embedded. For example, the gas supply part 21 is made of a conductive material such as aluminum whose inner surface or outer surface is anodized, and is electrically grounded (the grounded state is not shown). A gas flow path 22 extending horizontally is formed inside the gas supply part 21 , and a plurality of gas discharge holes 23 extending downward from the gas flow path 22 are provided on the lower surface of the gas supply part 21 . In addition, on the upper surface of the gas supply part 21, a gas supply pipe 24 which penetrates through the dielectric window 2 and communicates with the above-mentioned gas flow path 22 is connected. In addition, the gas supply pipe 24 penetrates the top plate of the processing container 10 and extends to the outside thereof, and is connected to a processing gas supply system 25 including a processing gas supply source, a valve system, and the like. The gas supply part 21 , the gas supply pipe 24 , and the process gas supply system 25 correspond to the process gas supply part of this example.

A high frequency (RF) antenna 3 is arranged in the antenna chamber 11 . The high-frequency antenna 3 is formed by arranging an antenna wire 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 a spacer 32 formed of an insulating member is provided to The dielectric windows 2 are spaced apart. In addition, the high-frequency antenna 3 may be a multiple antenna having a plurality of antenna parts.

The terminal 33 of the antenna wire 31 is connected to a power feeding member 34 extending above the antenna chamber 11 , and a high frequency power source 37 is connected to the upper end side of the feeding member 34 via the feeding wire 35 and the matching device 36 . Then, when a high-frequency power of, for example, a frequency of 13.56 MHz is supplied from the high-frequency power supply 37 to the high-frequency antenna 3 , an induced electric field is formed in the processing space 12 . As a result, the process gas supplied from the gas supply unit 21 is plasmaized by the induced electric field, and an inductively coupled plasma is generated. The configuration of the antenna wire 31 or the terminal 33 to the high-frequency power supply 37 corresponds to the plasma forming part of this example.

On the lower side in the processing space 12, the first electrode portion 41a and the second electrode portion 41b for placing a plurality of G6 half substrates G, for example, two sheets at adjacent positions spaced apart from each other, are arranged on the intervening medium. The power window 2 is opposite to the high-frequency antenna 3 . The first and second electrode portions 41 a and 41 b are provided on the common lower electrode 42 , and the first electrode portion 41 a and the lower electrode 42 and the second electrode portion 41 b and the lower electrode 42 are electrically connected to each other through their contact surfaces, respectively. Sexual conduction. For example, the first and second electrode portions 41a and 41b or the lower electrode 42 are made of aluminum, stainless steel, or the like.

The upper surface of the 1st electrode part 41a forms the 1st board|substrate mounting surface 51, and a board|substrate G is mounted. In addition, the upper surface of the second electrode portion 41b constitutes a second substrate placement surface 52, and another substrate G different from the above-mentioned one substrate G is placed, and common plasma processing is performed on the one substrate G and the other substrate G. The 1st, 2nd electrode part 41a, 41b is comprised by the metal plate of the rectangular shape in plan view. In addition, as shown in FIG. 2, even with respect to the 1st, 2nd board|substrate mounting surfaces 51 and 52, the shape of the board|substrate G is comprised so that a planar view rectangular shape is formed.

As shown in FIGS. 1 to 3 , in the plasma processing apparatus 1 of the present example, the first electrode portion 41 a and the second electrode portion 41 b are rectangular metal plates whose long sides are aligned in the same direction, and are arranged at a distance from each other. and adjacent locations. On the upper surfaces of the first and second electrode portions 41a and 41b and the side surfaces of the squares, for example, an insulating coating, that is, a thermal spray film 45 of aluminum oxide is formed. In addition, electrodes for chucks (not shown) are arranged inside the spray films 45 constituting, for example, the first and second substrate placement surfaces 51 and 52, and are supplied with a DC power source (not shown). The electrostatic attraction force generated by the DC power can attract and hold the substrate G.

The lower electrode 42 supporting the first and second electrode portions 41 a and 41 b from the lower surface is supported by the insulating member 46 from the lower surface side. For example, the insulating member 46 is formed into a rectangular ring body, and supports from the lower side and covers the peripheral portion of the lower electrode 42 and the side insulating member 73 of the lower electrode 42 from the side. Furthermore, a plurality of lift pins (not shown) are provided so as to penetrate the first and second electrode portions 41a, 41b, the lower electrode 42, and the bottom plate of the processing container 10 in the vertical direction, and a drive mechanism (not shown) can be used. shown) to raise and lower each lift pin. Due to the lifting action of the lift pins, the front end portions of the lift pins protrude from the first and second substrate placement surfaces 51 and 52, and the substrate G is received and received with an external substrate conveying mechanism.

In addition, a high-frequency power supply 55 is connected to the lower electrode 42 via a power supply line 53 and a matching device 54 . In the plasma treatment, by supplying high-frequency power from the high-frequency power supply 55 , high-frequency power for biasing is applied to the first and second electrode portions 41 a and 41 b via the lower electrode 42 . Since the space surrounded by the bottom plate of the processing container 10, the insulating member 46 and the lower electrode 42 is airtightly separated from the processing space 12, even if the bottom plate of the processing container 10 is provided with the aforementioned lift pins or power supply lines. 53 and the like pass through the openings, and a vacuum atmosphere is also maintained in the processing space 12 .

Inside the first and second electrode portions 41a and 41b, for example, an annular cooler flow path 411 extending in the circumferential direction is provided. In the cooler flow path 411, a heat transfer medium of a specific temperature, such as GALDE (registered trademark), is circulated and supplied by a cooler unit (not shown), the temperature of the heat transfer medium is adjusted, and the temperature of the heat transfer medium is controlled to be placed on the first and second electrode parts. The processing temperature of each substrate G on 41a, 41b. Furthermore, inside the first and second electrode parts 41a and 41b, there are provided the first and second substrate mounting surfaces 51 and 52 which are held from the lower electrode 42 side toward the first and second substrate mounting surfaces. A plurality of gas supply passages 412 penetrating in the direction. The gas supply path 412 supplies a heat transfer gas such as helium (He) gas to the back surface of the substrate G placed on the first and second substrate placement surfaces 51 and 52 .

Further, the lower electrode 42 is also used as a diffusion plate for the heat transfer gas that supplies the heat transfer gas to the gas supply paths 412 on the first and second electrode portions 41a and 41b sides. For example, a groove portion is formed on the upper surface of the lower electrode 42 . Furthermore, by arranging the first and second electrode portions 41a, 41b on the lower electrode 42, a gas flow path 421 surrounded by the lower surface of the electrode portions 41a, 41b and the groove portion is formed, and each gas supply path 412 The lower end is in a state of communicating with the gas flow path 421 . A supply piping (not shown) of the gas for heat transfer is connected to the gas flow path 421 .

In addition, between the peripheral edge portion of the upper surface of the lower electrode 42 and the first and second electrode portions 41a and 41b, and between the peripheral edge portion of the lower surface of the lower electrode 42 and the insulating member 46, the insulating member 46 and the processing container 10 Between the bottom surfaces, there are sealing members, namely O-rings 49, respectively. Furthermore, a vacuum exhaust mechanism 18 is connected to the exhaust port 16 on the bottom surface of the processing container 10 via an exhaust passage 17. A pressure adjustment unit (not shown) is connected to the vacuum evacuation mechanism 18 , and accordingly, the inside of the processing chamber 10 is configured to be maintained at a desired degree of vacuum. The exhaust passage 17 or the vacuum exhaust mechanism 18 corresponds to the vacuum exhaust portion of this example.

As shown in FIG. 2 , the first and second electrode portions 41 a and 41 b are provided with insulation made of alumina or the like so as to surround the first and second substrate mounting surfaces 51 and 52 , respectively. The ring portion 6 formed by the sexual ceramics. Since the ring portion 6 is arranged so as to face the plasma generating space, the plasma can be concentrated on the first and second electrode portions 41 a and 41 b (the first and second substrate placement surfaces 51 , 41 b , respectively) via the ring portion 6 . 52) Two substrates G on top.

For example, the upper surface of the ring portion 6 is arranged so that the upper surface and the height of the first and second substrate mounting surfaces 51 and 52 are aligned, and the side surfaces of at least the upper parts of the first and second electrode portions 41a and 41b are arranged around the entire circumference. It is surrounded by the ring portion 6 . As shown in FIG. 2 , the ring portion 6 is formed by combining a plurality of strip-shaped members, which are elongated bodies, and has a shape in which one strip-shaped member is arranged so as to traverse the central portion of the rectangular frame. In other words, it can also be said that the ring portion 6 is roughly configured in a shape in which the "8" shown in the seven-segment display is turned over. In addition, in FIG. 2, illustration of each strip-shaped member is abbreviate|omitted, and the shape of the ring part 6 after assembly is shown integrally.

For example, the thickness of the belt-shaped member constituting the ring portion 6 is set to a value within a range of 5 to 30 mm, and the width dimension of the belt-shaped member is set to a value within a range of 10 to 60 mm. At this time, the separation interval between the first substrate placement surface 51 and the second substrate placement surface 52 is set to 10 to 60 mm (length of the short side of the G6 half substrate G (750 mm) corresponding to the width dimension of the strip-shaped member. ) in the range of 2/25 to 1/75).

In addition, on the lower surface side of the ring portion 6, a side insulating member 73 is arranged so as to cover the four side surfaces when the first and second electrode portions 41a and 41b are viewed integrally, and the side surfaces of the lower electrode 42 located below. . The side insulating members 73 are made of insulating ceramics such as alumina or insulating resins such as polytetrafluoroethylene, and are formed into a rectangular ring body in plan view.

Furthermore, on the outer peripheral sides of the side insulating members 73 and the insulating members 46 , an outer ring portion 74 that covers the side surfaces of the side insulating members 73 and the insulating members 46 is arranged. For example, the outer ring portion 74 is made of the same ceramic as the ring portion 6 described above, and is a ring body having a rectangular shape in plan view. The rectangular frame body of the ring portion 6 is arranged on the upper surface of the side insulating member 73 and the outer ring portion 74. Further, the lower surface of the side insulating member 73 is supported by the insulating member 46 .

Here, in the configuration shown in the comparative form in FIG. 4 , a large electrode portion 40 covering the entire upper surface of the lower electrode 42 is provided on the lower electrode 42 . Then, by forming the recessed portion 400 so as to cross the center of the upper surface of the electrode portion 40, a part of the ring portion 6 is arranged in the recessed portion 400, and the first substrate mounting surface 51 and the second substrate mounting surface 52 are separated. In addition, in each of Figs. 4 to 8 described below, the same reference numerals as those used in Figs. 1 to 3 are given to the constituent elements common to the members described with reference to Figs.

However, as shown in the simulation results in the examples to be described later, it can be seen that the electric field strength at the arrangement position of the ring portion 6 separating the first substrate mounting surface 51 and the second substrate mounting surface 52 is higher in the comparative type. When the electric field strength becomes high at the arrangement position of the ring portion 6 , the ceramic constituting the ring portion 6 is cut and particles are generated, which also becomes a factor of contamination of the substrate G.

In particular, when the rectangular first and second substrate placement surfaces 51 and 52 are arranged to be adjacent to each other in the same direction as the long sides, the region where the electric field strength becomes high covers a wide range. There is a risk that the problem of particle generation becomes significant. In this regard, if the distance between the first substrate placement surface 51 and the second substrate placement surface 52 can be widened, the electric field intensity may be reduced, but this is not realistic due to the overall size of the plasma processing apparatus. .

Then, as shown in FIGS. 1 and 3 , in the plasma processing apparatus 1 of this example, two electrode portions (the first electrode portion 41 a and the second electrode portion 41 b ) are arranged on the lower electrode 42 to be spaced apart from each other, so as to The ring portion 6 is provided so as to surround both the periphery of the first substrate placement surface 51 and the periphery of the second substrate placement surface 52 . In addition, on the lower surface side of the ring portion 6 located between the first and second substrate placement surfaces 51 and 52, a dielectric material having a lower permittivity than that of the ceramic constituting the ring portion 6 is disposed. The dielectric member 44 can reduce the electric field intensity at the position where the ring portion 6 is arranged (refer to the simulation results of the embodiments described later).

In the plasma processing apparatus 1 shown in FIGS. 1 and 3 , the dielectric member 44 is provided so as to be filled on the side surfaces of the first and second electrode portions 41 a and 41 b facing each other with an interval therebetween, and on the lower surface of the ring portion 6 . and the space surrounded by the upper surface of the lower electrode 42 . In the case where the ring portion 6 is formed of alumina having a relative permittivity of about 9 to 11, as a dielectric having a lower permittivity than the alumina, a fluororesin (for example, a relative permittivity of polytetrafluoroethylene) can be exemplified. about 2) or quartz (the relative permittivity is about 4).

Furthermore, when compared with the electrode portion 40 of the comparative example in which the recessed portion 400 is formed, the first and second electrode portions 41a and 41b formed of a metal plate having a rectangular shape in plan view may also facilitate the spraying of the nozzle 7. The forming operation of the thermal spray film 45 can form the advantage of a dense thermal spray film 45 . That is, since the first and second electrode portions 41a and 41b related to the embodiment do not have concave portions where the spray film 45 should be formed, as shown in FIG. 5, the spray material can be passed from the spray nozzle. 7. The spraying is performed with the spraying angle being slightly perpendicular to the surface on which the spraying film 45 is to be formed. As a result, a dense spray film 45 with a high adhesion density of the spray material particles can be formed.

On the other hand, as shown in FIGS. 6( a ) and ( b ), in the electrode portion 40 related to the comparative type of the concave portion 400 in which the ring portion 6 is formed, the thermal spray film 45 is formed on the inner side surface of the concave portion 400 At this time, the discharge angle of the melt sprayed material from the melt injection nozzle 7 is about 50 to 60°. As a result, compared with the case where the discharge angle is set to be slightly vertical, the adhesion density of the spray material particles becomes lower, and the spray film 45 with poor compactness is formed, and abnormal discharge occurs between the plasma and the substrate G, which cannot be applied to the substrate G. Normal plasma processing concerns. In this regard, the first and second electrode portions 41a and 41b related to the embodiment in which the dense spray film 45 can be formed can effectively suppress the occurrence of abnormal discharge with the plasma.

The plasma processing apparatus 1 having the configuration described above is provided with a control unit 100 formed of, for example, a computer. The control unit 100 includes a data processing unit composed of a program, a memory, a CPU, and the like. In the program, by sending a control signal from the control unit 100 to each part of the plasma processing apparatus 1, a procedure set in advance is performed to The way in which the substrate G is subjected to plasma treatment, grouping commands. The program is stored in a computer storage medium such as a floppy disk, CD, and MO (Magnetic Optical Disk), which is not shown, and is installed in the control unit 100 .

The operation of the plasma processing apparatus 1 having the above-described configuration will be described. First, when the gate valve 15 of the plasma processing apparatus 1 is opened, the substrate G is carried into the processing space 12 by the substrate transfer mechanism (not shown). Then, the substrate G is supported by the lift pins by projecting the plurality of lift pins from the first substrate placement surface 51 . After the substrate conveyance mechanism is retracted from the processing space 12 , a substrate G is placed on the first substrate placement surface 51 side by lowering the lift pins. Next, another board|substrate G is mounted on the 2nd board|substrate mounting surface 52 by repeating the same operation|movement using the lift pins on the side of the 2nd board|substrate mounting surface 52. In addition, even if a board conveying mechanism capable of conveying two boards G in a state of horizontal alignment is used, the board G can be conveyed and received at the same time on the first and second board placement surfaces 51 and 52 . Next, DC power is supplied to the pinch electrode (not shown) in the spray film 45, and the substrate G is sucked and held.

After the substrate transfer mechanism is withdrawn from the processing space 12 , the gate valve 15 is closed, and the processing gas (eg, etching gas) supplied from the processing gas supply system 25 is diffused into the gas supply unit 21 and supplied to the processing through the gas discharge hole 23 . in space 12. Furthermore, the inside of the processing space 12 is adjusted to, for example, 0.66 to 26.6 Pa (5 to 200 mTorr) by evacuating the inside of the processing space 12 from the exhaust port 16 through the exhaust passage 17 to the vacuum exhaust mechanism 18 . The atmosphere of pressure left and right. Furthermore, in order to avoid the temperature rise or temperature change of the substrate G, He gas, which is a gas for heat transfer, is supplied to the back side of the substrate G through the gas supply path 412 .

Next, the above-mentioned high-frequency power of 13.56 MHz is applied to the high-frequency antenna 3 from the high-frequency power supply 37 , thereby forming a uniform induced electric field in the processing space 12 through the dielectric window 2 . The process gas supplied into the process space 12 is plasmatized by the induced electric field thus formed, and a high-density inductively coupled plasma is generated. The substrate G is subjected to plasma treatment by this plasma, for example, plasma etching of a specific film of the substrate G is performed.

At this time, by applying high-frequency power for biasing the first and second electrode portions 41a, 41b from the high-frequency power source 55, the plasma of the processing gas is attracted to the first and second electrode portions 41a, 41b side, Instead, an etching process with high verticality is performed. Furthermore, by providing the ring portion 6 made of ceramic, which is an insulating member, around the substrate G, the plasma is attracted to the substrate G side, and the plasma can be concentrated on the substrate G, thereby increasing the etching rate.

At this time, the lower surface side of the ring portion 6 located between the first and second electrode portions 41 a and 41 b is provided with a dielectric material having a lower dielectric constant than that of the ceramic constituting the ring portion 6 . The electric material member 44 can reduce the electric field intensity at the position where the ring portion 6 is arranged. As a result, generation of particles due to cutting of the ceramics constituting the ring portion 6 is suppressed, and contamination of the substrate G of the plasma processing apparatus can be reduced.

Furthermore, by using a metal plate having a rectangular shape in plan view as the first and second electrode portions 41a and 41b, a dense spray film 45 is formed on the surfaces of the first and second electrode portions 41a and 41b, thereby suppressing the plasma treatment. Abnormal discharge is generated, and normal plasma processing can be performed on the substrate G.

When the plasma etching is performed for a predetermined time, the supply of the process gas or the gas for heat transfer is stopped, and the application of the high-frequency power to the high-frequency antenna 3 and the first and second electrode portions 41a and 41b is stopped, and the electricity is terminated. pulp treatment. Then, the pressure in the processing space 12 is adjusted, the suction and holding of the substrate G is released, and the processed substrate G is carried out in the reverse order of the carrying in.

In the case of the plasma processing apparatus 1 according to this embodiment, it is provided so as to surround the first substrate placement surface 51 on the upper surface side of the first electrode portion 41a, and is arranged in the vicinity of the first electrode In the ceramic ring portions 6 on both sides of the periphery of the second substrate placement surface 52 on the upper surface side of the second electrode portion 41b adjacent to the second electrode portion 41a at a distance from each other, on the first and second substrate placement surfaces On the lower surface side of the ring portion 6 between 51 and 52, a dielectric member 44 made of a dielectric whose dielectric constant is lower than that of the above-mentioned ceramics is disposed. As a result, since the electric field intensity in the ring portion 6 arranged between the first and second substrate mounting surfaces 51 and 52 can be reduced, for example, the difference between the width of the first and second substrate mounting surfaces 51 and 52 can be increased. By arranging the space to lower the electric field intensity, it is possible to avoid an increase in the size of the plasma processing apparatus 1 and to suppress the generation of particles from the ring portion 6 due to an increase in the electric field intensity.

Here, the first and second electrode portions 41 a and 41 b constituting the first and second substrate mounting surfaces 51 and 52 are not limited to those having a rectangular shape in plan view in which the sides facing each other are flat as described using FIGS. 1 to 3 . The case of metal plate composition. For example, as shown in FIG. 7 , even at the position on the lower side of the respective side surfaces of the first and second electrode portions 41a' and 41b' that face each other, protruding toward the opposite electrode portion 41b', 41a' side, respectively, are arranged. The protrusions 413 in the shape of flanges whose front ends are butted against each other may also be used. In addition, the front ends of the protruding portions 413 arranged so as to be in contact with each other may not be in contact with each other, and a gap of about several millimeters may be formed between the front ends.

At this time, the dielectric member 44 is provided so as to be filled on the side surfaces of the first and second electrode portions 41 a ′ and 41 b ′ facing each other with a space between them, and the lower surface of the ring portion 6 , and the first and second electrodes. The space surrounded by the upper surfaces of the protruding parts 413 and 413 of the parts 41a' and 41b'.

In this example, by covering the upper surface of the lower electrode 42 on which the spray film 45 is not formed with the protrusion 413 on which the spray film 45 is formed, the insulation between the plasma and the lower electrode 42 is improved, and further suppression of The occurrence of abnormal discharge. In addition, even when the thermal spray film 45 is formed on the first and second electrode portions 41a' and 41b' provided with the protruding portions 413, the combination of the first and second electrode portions 41a' and 41b' is caused by the thermal spraying process. Therefore, the spraying material can be sprayed so that the discharge angle of the spraying material from the spraying nozzle 7 is perpendicular to the upper surface of the protruding portion 413 , and the dense spraying film 45 can be formed.

In addition, in the example shown in FIG. 8, in addition to the 1st, 2nd electrode part 41a, 41b, the lower stage side electrode is also divided|segmented into 1st, 2nd lower stage side electrode 42a, 42b. That is, the first electrode portion 41a is provided on the first lower-stage side electrode 42a that is electrically conductive with each other, and the second electrode portion 41b is provided at a position spaced apart from and adjacent to the first lower-stage side electrode 42a , and are provided on the second lower-stage side electrode 42b that is electrically connected to the second electrode portion 41b.

Between the first electrode portion 41a and the first lower electrode 42a, and between the second electrode portion 41b and the second lower electrode 42b, gas flow paths for supplying the heat transfer gas to the respective gas supply paths 412 are formed 421. Furthermore, the high-frequency power supply 55 is connected to the first and second lower-stage side electrodes 42a and 42b, respectively, and is applied to the first and second electrode portions 41a and 41b via the first and second lower-stage side electrodes 42a and 42b. high frequency power.

In the example shown in FIG. 8, the insulating member 46 is formed by combining a rectangular ring body and a rod body connecting the middle points of the two long sides of the ring body, and has a "Japanese shape" in plan view. Further, the dielectric member 44 is provided so as to be filled in the side surfaces of the first and second electrode portions 41a and 41b and the side surfaces of the first and second lower stage side electrodes 42a and 42b, which are opposed to each other with an interval therebetween, and the ring portion 6 the space surrounded by the insulating member 46 under it. For example, the dielectric member 44 is supported by the above-described rod body, that is, the insulating member 46 . In addition, even if the flange-shaped support member is protruded from the first and second lower stage side electrodes 42a and 42b, the dielectric member 44 is supported by the support member instead of the insulating member 46 that is provided as the rod body. The method of the dielectric member 44 may also be used.

Here, the method of arranging the first and second electrode portions 41a and 41b at the bottom of the processing space 12 is not limited to the insulating member 46 formed as a rectangular ring as shown in FIGS. 1 , 3 , 7 and 8 . On the upper surface, the lower electrode 42 (or the first lower electrode 42a, the second lower electrode 42b), the first electrode part 41a, the second electrode part 41b (or the first electrode part 41a', the second electrode part 41b) are provided. 41b'), the case of the assembly structure of the dielectric member 44, the ring portion 6, the side insulating member 73, and the outer ring portion 74 (equivalent to the mounting table of the substrate G). For example, a telescopic body that airtightly connects between the lower electrode 42 and the bottom plate of the processing container 10 is provided with a telescopic body, and inside the telescopic body, a column that can be lifted and lowered so as to penetrate the bottom plate is arranged, and the upper end of the column is located at the upper end of the column. The lower electrode 42 may be connected via an insulating member. At this time, for example, on the bottom plate of the processing container 10, at the positions of the first and second substrate placement surfaces 51 and 52, respectively, a substrate receiving and receiving mechanism with a plurality of receiving and receiving pins (not shown in the figure) is installed, and the support is lowered by the support. The receiving and receiving pins protrude from the first and second substrate mounting surfaces 51 and 52, and the receiving and receiving pins are used to perform receiving and receiving of the substrate G with the external substrate conveying mechanism.

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

In addition, in each of the above-described embodiments, the plasma processing is performed by plasma processing the processing gas by inductive coupling. However, the method of plasma forming the processing gas by the plasma forming unit is not limited to this example. Even if a capacitive coupling is formed by applying high-frequency power between the metal gas supply portion 21 and the first and second electrode portions 41a and 41b, a capacitively coupled plasma for plasmatizing a process gas is used, or microwaves are introduced into the process gas. The space 12 may be used for plasma treatment by applying a microwave plasma to plasmaize the processing gas. Even in these cases, high-frequency power for plasma formation or ion introduction is applied to the first and second electrode portions 41a and 41b. Here, even in these plasma forming means, the dielectric member 44 is provided on the lower surface side of the ring portion 6 provided between the first and second substrate mounting surfaces 51 and 52 to reduce the The electric field strength at the arrangement position of the ring portion 6 .

In addition, the type of plasma processing performed using the plasma processing apparatus 1 of this example is not limited to the above-described etching processing and ashing processing, and may be film formation processing performed on the substrate G. Furthermore, the type of substrate G is not limited to the G6 half-substrate example described above, and rectangular substrates of other sizes are also acceptable. In addition, the present invention is not limited to rectangular substrates for FPD, and the present invention can be applied even when processing rectangular substrates for other applications such as solar cells. Otherwise, the present invention can be applied to circular substrates such as semiconductor wafers. [Example]

(Simulation) The difference between the electric field intensity generated on the surface of the ring portion 6 when the dielectric member 44 is provided on the lower surface side of the ring portion 6 and when the dielectric member 44 is not provided is confirmed by simulation. A. Simulation conditions (Example 1) A ceramic plate with a width of 35mm and a thickness of 10mm (specific permittivity: 9.9, equivalent to the ring portion 6) was fabricated on the lower surface side, and a polytetrafluoroethylene with a width of 35mm and a thickness of 35mm was arranged Vinyl dielectric member 44 (specific permittivity: 2.0), and on both sides of the ceramic plate and the dielectric member 44, corresponding to the first and second electrode portions 41a, 41b are arranged A simulation model of aluminum. This model corresponds to the implementation shown in FIGS. 3 and 7 . Furthermore, when a specific RF voltage is applied to aluminum, the aluminum exposed on the upper surface side and the electric field intensity at each position of the ceramic plate are simulated. (Example 2) The same simulation as in Example 1 was performed except that the thickness of the dielectric member 44 was set to 60 mm. This model corresponds to the implementation shown in FIG. 8 . (Comparative Example 1) The same simulation as in Example 1 was performed except that the dielectric member 44 was not provided, and that aluminum was also arranged on the lower surface side of the ceramic plate. This model corresponds to the comparison pattern shown in Figure 4.

B. Simulation results Fig. 9 shows the simulation results of Examples 1, 2 and Comparative Example 1. The horizontal axis of FIG. 9 represents the coordinate position [m] in the width direction when the center position of the width dimension of the ceramic plate corresponding to the ring portion 6 is taken as the origin, and the vertical axis represents the electric field intensity [arbitrary unit]. Since the simulation results of Examples 1 and 2 are almost the same, they are represented by a solid line, and the simulation results of Comparative Example 1 are represented by a broken line.

From the results of Examples 1 and 2 shown in FIG. 9 , it can be seen that the electric field strength is the lowest at the center position in the width direction, and the electric field strength is directed toward the width direction of the ceramic plate with the dielectric member 44 arranged on the lower side. The distribution of the electric field intensity rises rapidly after the edge gradually rises. Furthermore, the simulation of Example 1 was performed as a complex simulation model in which the thickness of the dielectric member 44 was changed in the range of 5 to 35 mm. Even the results of these simulations are slightly the same as the results of Example 1 shown in FIG. 9 .

In contrast, in Comparative Example 1, a flat electric field intensity distribution was formed in the inner region of the position where the electric field intensity rapidly increased, and the value at any position was higher than that of Examples 1 and 2. From these simulation results, it can be seen that compared with the method of arranging the ring portion 6 in the concave portion 400 of the electrode portion 40 shown in FIG. The method of disposing the low-ceramic dielectric member 44 constituting the ring portion 6 on the lower surface side can reduce the electric field intensity on the surface of the ring portion 6 .

G‧‧‧Substrate 1‧‧‧Plasma processing apparatus 10‧‧‧Processing container 12‧‧‧Processing space 18‧‧‧Vacuum exhaust mechanism 21‧‧‧Gas supply unit 3‧‧‧High-frequency antennas 41a, 41a '‧‧‧First electrode part 41b, 41b'‧‧‧Second electrode part 412‧‧‧Gas supply path 413‧‧‧Projecting part 42‧‧‧Lower stage side electrode 42a‧‧‧First lower stage side electrode 42b‧ ‧‧Second lower stage side electrode 421‧‧‧Gas flow path 44‧‧‧Dielectric member 45‧‧‧Spray film 51‧‧‧First substrate mounting surface 52‧‧‧Second substrate mounting surface 6 ‧‧‧Ring

FIG. 1 is a vertical cross-sectional side view of a plasma processing apparatus related to an embodiment. Fig. 2 is a plan view of the first and second electrode portions provided in the above-mentioned plasma processing apparatus. Fig. 3 is a longitudinal cross-sectional side view of the first and second electrode portions. Fig. 4 is a longitudinal cross-sectional side view of the first and second electrode portions of the comparative type. Fig. 5 is a schematic diagram showing a thermal spraying operation of alumina on the first and second electrode portions according to the embodiment. Fig. 6 is a schematic diagram showing a thermal spraying operation of alumina on the first and second electrode portions of the comparative type. Fig. 7 is a longitudinal cross-sectional side view related to the first and second electrode portions of another embodiment. Fig. 8 is a longitudinal cross-sectional side view related to the first and second electrode portions of another embodiment. Fig. 9 is an explanatory diagram showing a simulation result of the electric field intensity on the surface of the ring portion.

1‧‧‧Plasma processing device

2‧‧‧Dielectric Window

3‧‧‧HF antenna

6‧‧‧Ring

10‧‧‧Disposal container

11‧‧‧Antenna Room

12‧‧‧Processing space

13‧‧‧Support member

14‧‧‧Moving in and out

15‧‧‧Gate valve

16‧‧‧Exhaust port

17‧‧‧Exhaust circuit

18‧‧‧Vacuum exhaust mechanism

21‧‧‧Gas Supply Department

22‧‧‧Gas flow path

23‧‧‧Gas discharge hole

24‧‧‧Gas supply pipe

25‧‧‧Processing gas supply system

31‧‧‧Antenna wire

32‧‧‧Spacers

33‧‧‧Terminal

34‧‧‧Power supply components

35‧‧‧Power cable

36‧‧‧matcher

37‧‧‧High Frequency Power Supply

41a‧‧‧First electrode part

41b‧‧‧Second electrode part

42‧‧‧Lower side electrode

44‧‧‧Dielectric components

45‧‧‧Spray film

46‧‧‧Insulation components

49‧‧‧O-ring

53‧‧‧Power supply line

54‧‧‧Matchers

55‧‧‧High Frequency Power Supply

73‧‧‧Side insulation member

74‧‧‧Outer ring

100‧‧‧Control Department

111‧‧‧Sidewall

121‧‧‧Sidewall

411‧‧‧Cooler flow path

412‧‧‧Gas supply circuit

421‧‧‧Gas flow path

G‧‧‧Substrate

Claims (10)

A plasma processing apparatus for subjecting a substrate to be processed to plasma processing by a plasmatized processing gas, the plasma processing apparatus comprising: a processing container configured to perform the above-mentioned plasma processing A processing space for processing, and is connected to a processing gas supply part that supplies processing gas to the processing space, and a vacuum evacuation part that performs vacuum evacuation of the processing space; Plasma forming part, which is to be supplied to the processing The processing gas in the space is plasmaized; the first electrode part made of metal is arranged in the above-mentioned processing space, and the upper surface thereof constitutes a first substrate mounting surface for mounting a substrate to be processed, and a high frequency is applied. Electricity; a second electrode part made of metal, which is provided at a position spaced apart from and adjacent to the first electrode part in the processing space, and the upper surface of which is configured to mount another substrate different from the one to be processed. The second substrate placement surface of the substrate to be processed, and high-frequency power is applied; a ceramic ring portion, viewed from the upper side, surrounds the periphery of the first substrate placement surface and the periphery of the second substrate placement surface both; and a dielectric member provided on the lower surface side of the ring portion located between the first and second substrate placement surfaces, and filling the spaced first electrode portions on the lower surface side of the ring portion The space between the side surface of the second electrode portion and the side surface of the second electrode portion is formed of a dielectric material whose dielectric constant is lower than that of the above-mentioned ceramics. The plasma processing apparatus of claim 1, wherein the first electrode portion and the second electrode portion are provided on a common lower-stage side electrode that is electrically conductive with the first and second electrode portions, and the first electrode portion and the second electrode portion pass through the lower stage. The side electrodes apply high-frequency power to the first and second electrode portions. The plasma processing apparatus according to claim 2, wherein the dielectric member is provided so as to fill the side surfaces of the first and second electrode portions facing each other with an interval therebetween, the lower surface of the ring portion, and the lower stage The space surrounded by the upper surface of the side electrodes. The plasma processing apparatus as set forth in claim 2, wherein the electrode portion side protruding toward the other side is formed at a position on the lower side of each of the side surfaces of the first and second electrode portions that face each other with an interval therebetween, and is arranged such that The flange-shaped protruding portions whose front end portions are butted against each other, and the dielectric member is provided so as to fill the side surfaces of the first and second electrode portions facing each other with an interval therebetween, and the lower surface of the ring portion, and the first and second electrode portions. , The space surrounded by the upper surface of each protruding part of the second electrode part. The plasma processing apparatus as set forth in any one of claims 2 to 4, wherein between the first electrode portion and the lower electrode, and between the second electrode portion and the lower electrode, there are respectively formed so as to pass through The plurality of gas supply passages penetrating the first and second electrode portions in the up-down direction are supplied with gases for heat transfer toward the back surface of the substrate to be processed mounted on the first and second substrate mounting surfaces. flow path. The plasma processing apparatus according to claim 1, wherein the first electrode portion is provided on the first lower stage side electrode that is electrically conductive with each other, and the second electrode portion is arranged on the first lower stage side electrode. The positions where the electrodes are spaced apart and adjacent to each other are electrically connected to the second lower electrode portion, and the high frequency power is applied to the first and second lower electrodes via the first and second lower electrodes. 2 electrode parts. The plasma processing apparatus according to claim 6, wherein the dielectric member is provided so as to fill the side surfaces of the first and second electrode portions and the side surfaces of the first and second lower-stage side electrodes facing each other with an interval therebetween , and the space enclosed under the above-mentioned ring portion. The plasma processing apparatus as set forth in claim 6 or 7, wherein between the first electrode portion and the first lower electrode, and between the second electrode portion and the second lower electrode, there are formed to pass through The plurality of gas supply passages penetrating the first and second electrode portions in the up-down direction are supplied with gases for heat transfer toward the back surface of the substrate to be processed mounted on the first and second substrate mounting surfaces. flow path. The plasma processing apparatus according to any one of claims 1 to 4, 6, and 7, comprising the upper surface of the first electrode portion of the first substrate placement surface, and the side The upper surface and the side surface of the second electrode portion including the second substrate placement surface are covered with an insulating coating. The plasma processing apparatus according to any one of claims 1 to 4, 6, and 7, wherein the ceramic constituting the ring portion is alumina, and the dielectric constituting the dielectric member is fluororesin or quartz.

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