KR101208700B1 - Ceramic heater having strap for ground - Google Patents

Abstract

PURPOSE: A ceramic heater having a grounding strap is provided to be mounted on a path on a lower part of a shaft to be suitable for the front side shape of a strap by having a rectangular shape of a predetermined width on the front side. CONSTITUTION: A heater plate(20) applies heat to a substrate. The heater plate has an RF electrode for generating plasma. A shaft(10) is mounted on the bottom surface of the heater plate. Inside the shaft an RF load(32) is stored to penetrate upwardly and downwardly. The shaft is electrically connected with the RF load.

Description

CERAMIC HEATER HAVING STRAP FOR GROUND}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic heater, which is chemically vapor-deposited by converting a gas in the chamber into a plasma in a plasma reaction chamber, and more particularly, a rod in grounding a rod electrically connected to an electrode for generating plasma. The present invention relates to a ceramic heater provided with a grounding strap that stretches against thermal expansion and maintains a stable ground state and maintains durability without damage even after repeated thermal expansion.

Chemical Vapor Deposition (CVD) is a process of forming various types of thin films on the surface of substrates such as silicon wafers and glass panels in the manufacture of semiconductor devices and flat panel display devices. Plasma enhanced chemical vapor deposition (PECVD) is widely used.

Plasma chemical vapor deposition process is a ceramic heater (3) inside the chamber (1) having an injection port (1-2) for injecting the reaction gas and the outlet (1-3) for discharging the reaction gas as shown in FIG. In the state in which A) is accommodated, the substrate 2 is mounted on the upper surface of the ceramic heater A and deposited.

Specifically, the ceramic heater A includes a heater plate 21 having a heater element 21 for applying heat and an RF electrode 22 for applying a radio frequency voltage, and a bottom surface of the heater plate 20. It is mounted to the heater element 21 and the RF electrode 22 serves as a passage for supplying electricity and consists of a shaft (10) also serves as a support for supporting the heater plate 20. In addition, the shaft 10 accommodates the heater rod 31 electrically connected to the heater element 21 and the RF rod 32 electrically connected to the RF electrode 22 to penetrate the inside up and down, and at the bottom thereof. The heater rod 31 is connected to an external heater power source 3, and the RF rod 32 can be connected to an external electrode power source 4. To this end, the shaft 10 has a heater insert 11 for inserting the heater rod 31 and an RF rod insert 12 for inserting the RF rod 32. In addition, a separate electrode 1-1 connected to the electrode power source 4 is provided inside the chamber 1, and a radio frequency voltage applied between the RF electrode 22 and the chamber internal electrode 1-1 is provided. The reaction gas injected into the chamber 1 is converted into a plasma to be deposited on a substrate. Here, electricity is also supplied to the heater element 21 to generate a plasma to maintain a constant temperature.

The plasma chemical vapor deposition apparatus illustrated in FIG. 1 is briefly illustrated. Although not shown in FIG. 1, a passage for accommodating the substrate 2 into the chamber and a shower head for injecting reaction gas into the chamber are shown. , Control means for controlling the injection and discharge of the reaction gas, cooling means of the shaft, a thermocouple for measuring the temperature of the ceramic heater (A), and the like.

On the other hand, the lower end of the RF rod 32 penetrating the shaft 10 up and down is grounded to the lower end of the shaft 10 by the ground connector 40. Here, the ground connector 40 is to maintain the plasma formed inside the chamber 1 in a uniform state, and the ceramic heater A is repeatedly heated to 400 to 550 ° C. and lowered to room temperature during preventive maintenance. By repetition of heating and cooling, even if thermal expansion and thermal contraction of the RF rod 32 is repeated, it should be configured to maintain a good ground state between the RF rod 32 and the shaft 10.

The structure of the grounding connector 40 to meet these requirements is, Utility Model Registration No. 20-0420693, Publication No. 10-2009-0042050, Publication No. 10-2008-0046898, Publication No. 10- Proposed in 2011-0071162 et al. Utility Model No. 20-0420693 clamps a clamp to an RF rod and forms a ground path with the flexible conducting sheet between the clamp and the shaft, so that the flexible conducting sheet bends the stretch length due to thermal expansion even if thermal expansion of the RF rod occurs. To lose. Accordingly, the flexible conductive sheet according to the Utility Model Registration No. 20-0420693 was firmly fixed to the clamp and the shaft, thereby reducing the occurrence of arc. Patent Publication No. 10-2009-0042050 is an improvement of the Utility Model No. 20-0420693, which forms the part holding the RF rod and the part fixed to the shaft in a rigid shape without bending and connecting both parts to the bending part. It is constructed in one piece to prevent source arcs from occurring at fixed points. The grounding method according to Korean Patent Laid-Open Publication Nos. 10-2008-0046898 and 10-2011-0071162 employs a method of connecting a cable between an RF rod and a shaft.

However, the above-described prior arts require sufficient space for installing the ground connector 40, so that it is very difficult to cut and install the lower end of a shaft having a thermocouple and a cooling passage as well as an RF rod and a heater rod. It became. That is, when looking at the above-described conventional techniques in detail when forming the mounting groove to install the ground connector 40 at the bottom of the shaft is formed by greatly cutting the periphery of the RF rod and clamp the RF rod in the interior of the mounting groove The mounting grooves had to be formed by connecting the inner sidewalls of the mounting grooves with flexible conductors. In addition, the mounting groove of a sufficient size was required to fasten the bolt for fixing the flexible conductor.

Further, Patent Publication Nos. 10-2009-0042050, 10-2008-0046898, and 10-2011-0071162 disclose a modification of Utility Model No. 20-0420693 composed of a flexible conductive sheet. , RF rod by bending the connection member (bending in the Patent Publication No. 10-2009-0042050, the cable in the Patent Publication Nos. 10-2008-0046898 and 10-2011-0071162) connected to the horizontal plane However, in view of the convenience of installation, it is better to use the flexible conductive sheet proposed in the Utility Model Registration No. 20-0420693.

However, the flexible conductive sheet proposed in Korean Utility Model Registration No. 20-0420693 has a 'U' shape when viewed from the side by bending an intermediate portion to impart flexibility, so that the RF rod is thermally expanded when the RF rod is thermally expanded. As the cabinet of one bent portion was deformed in a smaller direction, it was easy to be cut by repeated deformation. This resulted in an accidental process interruption due to the deterioration of durability, and in order to prevent this, the flexible conductive sheet had to be frequently replaced to take productivity and maintenance difficulties.

Therefore, the ground connector 40 mounted on the ceramic heater is composed of a conductive sheet, but can be installed without wide cutting the periphery of the RF rod, so that the installation space can be easily installed at the shaft end where the installation space is narrow. It guarantees durability against repeated expansion, and as pointed out as a problem in Korean Patent Laid-Open Publication No. 10-2009-0042050, as both ends are fixed with a conductive sheet as 'U', a fixed point is raised during thermal expansion of the RF rod, and at room temperature. It is required to configure to solve the problem that the arc occurs in the contact again.

KR 20-0420693 Y1 2006.06.28. KR 10-2009-0042050 A 2009.04.29. KR 10-2008-0046898 A 2008.05.28. KR 10-2011-0071162 A 2011.06.29.

Therefore, an object of the present invention is to connect the lower end of the RF electrode to the shaft with a conductive sheet, the conductive sheet can be installed in a narrow space can be installed on the shaft without constraints, ensuring durability against repeated thermal expansion of the RF electrode The present invention provides a ceramic heater having a grounding strap for preventing arcing.

In order to achieve the above object, the present invention, the heater plate 20 is applied to the substrate accommodated in the plasma reaction chamber is mounted on the upper surface, the RF electrode 22 for plasma generation; It is mounted on the bottom of the heater plate 20, and accommodates the RF rod 32 which is electrically connected to the RF electrode 22 to penetrate up and down therein, and is cut in the lower side toward the RF rod 32. In the ceramic heater comprising a; the mounting groove 200 after the mounting groove 200 is mounted to the ground connector 100, the shaft 10 electrically connected to the RF rod 32;

The ground connector 100 includes a clamp 130 mounted to the RF rod 32 exposed inside the mounting groove 200; It is formed of a vertically conductive band is inserted into the mounting groove 200, the lower end is fixed to the clamp 130, and after bending the middle portion two or more times, the upper end closer to the outer surface of the shaft 10 A strap 110 having an upper end fixed to an outer side of the upper side rather than a lower end, and extending the bent portion when the RF rod 32 is thermally expanded to form a curvature of the bent portion so that the lower end can be moved downward. It is characterized by including.

The strap 110, while bending the middle portion twice, while the lower end is vertically fixed to the clamp 130, the angle of the first bend following the lower end to the right or obtuse angle toward the outside of the shaft 10 And the second bend is formed so that the upper end fixed to the shaft faces the vertical direction.

The mounting groove 200 is provided with a step in accordance with the second bent shape of the strap 110 is in close contact with the strap 110, but chamfering (chamfering) so as not to touch the second bend of the strap 110. It is done.

The strap 110 is made of beryllium copper material and has a shape of a band having a thickness of 0.1 to 0.4 mm, and is characterized in that the curvature radius of the bent portion is formed to 1.2 to 4.5 mm.

The strap 110 is formed in the upper and lower ends of the screw holes 116 and 117 to penetrate the bolts 140 and 141, respectively, and are fixed to the clamp 130 and the shaft 10 by bolting. 116, 117 is characterized in that it is formed longer up and down than the width.

The mounting groove 200 is equipped with an insulating case 120 which is in close contact with a surface other than the surface on which the upper end of the strap 110 is fixed, so that the RF rod 32 does not directly contact the shaft 10. And, except for the upper portion of the strap 110 and the clamp 130 is characterized in that to be mounted inside the insulating case 120.

The mounting groove 200 is characterized in that it is formed with a passage for pushing the lower end of the strap 110 from the side in the surface contact direction with the clamp 130.

According to the present invention configured as described above, the strap 110, which is electrically grounded between the lower portion of the RF rod 32 and the lower portion of the shaft 10, is formed to bend to be unfolded in accordance with thermal expansion of the RF rod 32 to form a bent portion. It reduces fatigue and can be used for a long time without breaking the bent part.

In addition, the present invention bends the conductive strip to form a grounding strap, but when viewed from the front to have a rectangular shape having a constant width, to form a passage to fit the front shape of the strap at the bottom of the shaft 10 to be mounted Accordingly, there is also a passage for inserting the thermocouple and a passage for injecting and discharging the coolant, which can be installed without restriction on the lower end of the shaft 10 allowing only a narrow installation space.

In addition, the present invention is installed by forming a grounding strap with a conductive strip, and does not generate an arc so that the bent portion does not touch the shaft 10, thereby increasing the durability.

1 is an illustration of the use of a common ceramic heater.
2 is a bottom perspective view of a ceramic heater having a grounding strap according to an embodiment of the present invention.
3 is a bottom view of a ceramic heater with a grounding strap in accordance with an embodiment of the present invention.
4 is a side cross-sectional view of a ceramic heater with a grounding strap in accordance with an embodiment of the present invention.
5 is a bottom separated perspective view illustrating a mounting method of the ground connector 100 in the ceramic heater having the grounding strap according to the embodiment of the present invention.
6 is a side view and a front view of the strap in the ceramic heater with a grounding strap according to an embodiment of the present invention.
Figure 7 is a side view showing the shape change of the strap due to thermal expansion of the RF rod.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that, in the drawings, the same reference numerals are used to denote the same or similar components in other drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

2 to 6 are views for explaining a ceramic heater having a ground strap according to an embodiment of the present invention, Figure 2 is a bottom perspective view of the ceramic heater, Figure 3 is a bottom view of the ceramic heater, Figure 4 5 is a bottom side cross-sectional view of the ceramic heater, FIG. 5 is an exploded perspective view illustrating a mounting method of the ground connector 100, and FIG. 6 is a side view (a) and a front view (b) of the strap.

2 to 6, the ceramic heater having a grounding strap according to an embodiment of the present invention includes a heater plate 20 and a heater plate 20 accommodated in a plasma reaction chamber and having a substrate mounted thereon. A shaft mounted on a bottom surface of the shaft) to support the heater plate 20 and having a passage for supplying electricity, and a rod accommodated in a passage formed in the shaft 10 to vertically penetrate the shaft 10. 30: 31, 32, and a ground connector 100, which grounds the RF rod 32 to the bottom of the shaft 10, among the rods.

Here, the heater plate 20, the shaft 10 and the rods (30: 31, 32) is a known technique, it will be briefly described.

The heater plate 20 is formed in the form of a plate on which the substrate can be mounted on the upper surface, and also incorporates an RF electrode corresponding to the electrode in the chamber to apply a radio frequency voltage at both ends of the RF electrode and the electrode in the chamber. This creates a plasma in the chamber, and also incorporates a heater element that heats the substrate to a constant temperature to create a chemical vapor deposition environment of the plasma.

The shaft 10 is vertically fixed to the bottom of the heater plate 20 to support the heater plate 20, and a plurality of passages are formed to penetrate up and down. Here, the passages include a passage or shaft 10 and a heater plate 20 for inserting a thermocouple for measuring the temperature of the heater plate 20 in addition to the passages for inserting the heater rod 31 and the RF rod 32 described below. ) May include a passage of coolant that lowers the temperature of the shaft 10 to protect the O-ring (not shown) being filled. These passages are arranged one by one, the heater insertion passage for inserting the heater rod 31, the RF rod insertion passage for inserting the RF rod 32, the thermocouple insertion passage 13 for inserting the thermocouple, and the injection and discharge of cooling water. It consists of a coolant passage 14.

The rods 30: 31 and 32 are inserted into a passage formed in the shaft 10, and the heater rod 31 electrically connected to the heater element and the RF rod 32 electrically connected to the RF electrode. ). Here, since the heater rod 31 and the RF rod 32 are respectively exposed to the bottom surface of the shaft 10 through the shaft 10, the heater rod 31 and the RF rod 32 are connected to the heater plate 20 by connecting a portion exposed to the bottom surface to an external power source. It serves as an electrical connection for applying a voltage to the built-in heater element and the RF electrode.

In addition, the lower portion of the shaft 10 is cut off around the lower end of the RF rod 32 to form a mounting groove 200 used as a space for grounding, and then exposed to the inside of the mounting groove 200 The RF rod 32 is grounded by electrically connecting the RF rod 32 to the lower end of the shaft 10 using the ground connector 100.

According to an embodiment of the present invention, the ground connector 100 for grounding the RF rod 32 to the shaft 10 excludes an inner surface of the mounting groove 200 (except the inner surface of the strap fixing groove described later). The clamp 130 and the lower end 112 which are mounted while holding the lower end of the RF rod 32 inside the insulating case 120 and the insulating case 120 covered with a thin thickness are attached to the clamp 130. A strap 110 formed of a conductive strip that is fixed and fixed to an upper surface 111 of the mounting groove 200 which is not covered by the insulating case 120 (the inner surface of the strap fixing groove described later), and the strap 110. It comprises a plurality of bolts (140, 141) for fixing the bottom 112 and the top 111 of the.

The clamp 130 is formed so as to penetrate up and down, the rod through hole 131 of one side for inserting the lower end of the RF rod 32, the vertical incision toward the rod through hole 131 from the other side Formed but cut portion 132 formed to have a predetermined width, the female thread groove 133 formed on one side bisected by the cut portion 132 on the other side, and the other divided by the cut portion 132 on the other side Is formed on the side is formed of a terminal-shaped terminal having a through hole 134 is formed in accordance with the position of the female screw groove 133. Here, the cutout 132 is the opposite side (the side through which the through-hole is formed) that is in contact with the lower end of the strap 110 when the incision to divide the other side of the clamp 130 (the female thread groove is formed) Side) to form a thinner, and through the bolt through the through hole 134 and screwed into the female thread groove 133, the width of the incision 132 is narrowed and the both sides are in close contact, the rod through hole 131 The inner diameter of is reduced to grip the RF rod (32).

As such, when the clamp 130 is mounted on the lower end of the RF rod 32 exposed to the inside of the mounting groove 200 formed at the bottom of the shaft 10, the clamp 130 is an outer surface of the shaft 10. Rather than inside.

The strap 110 is formed of a conductive strip and is inserted into the mounting groove 200, and the bolt 141 is formed on a surface on which the through hole 134 of the clamp 130 is vertically erected. In the state of fixing by screwing, the middle portion is bent twice so that the upper end 111 is formed to lie outside the upper side than the lower side 112. Accordingly, the upper end 111 of the strap 110 may be grounded by being fixed close to the outer surface of the shaft 10 (fixed by bolting to the strap fixing groove to be described later).

The strap 110 formed and mounted as described above is stretched as the RF rod 32 thermally expands, and when the lower end of the RF rod 32 moves downward, the bent portion is unfolded by the clamp 130. The RF rod 32 can be maintained in an electrically connected state, and since the bent portion is stretched in the reverse direction to the bending direction, fatigue strength of the bent portion can be reduced. Thus, durability of the bent portion can be ensured.

Here, since the maximum extension length due to thermal expansion of the RF rod 32 may vary depending on the maximum heating temperature of the ceramic heater and the length of the RF rod 32, the bendings 114 and 115 of the strap 110 may be It has a radius of curvature of sufficient size to allow the RF rod 32 to stretch to the maximum extension length.

A specific embodiment of the strap 110 will be described.

According to an embodiment of the present invention, the strap 110 is shown in Figure 6a by bending two different positions at the middle of the vertically-conductive band as shown in Figures 5 and 6, respectively. As shown in b of FIG. 6, it has a shape that is bent twice (114, 115) as shown in FIG.

'자로 보인다. 즉, 상기 스트랩(110)은 전도성 띠를 수직으로 세워 하단(112)에 이어지는 첫번째 절곡(115)의 각, 즉, 하단(112)과 중간(113)이 이루는 각이 직각 또는 둔각을 이루게 하고, 중간(113)과 상단(111) 사이에 절곡되는 두번째 절곡(114)의 각은 상단(111)이 연직방향을 향하게 결정된다. In other words, the strap 110 is bent (114, 115) the middle portion twice, and when viewed from the side '

'Looks like. That is, the strap 110 vertically or concave angle of the first bend 115, ie, the lower end 112 and the middle 113, the conductive band to the vertical to the bottom 112, The angle of the second bend 114 that is bent between the middle 113 and the top 111 is determined such that the top 111 faces in the vertical direction.

'자형으로 스트랩(110)을 형성하여 샤프트(10)에 장착할 때에 샤프트(10)의 크기를 감안하여 스트랩(110)의 중간(113) 길이를 대략 1cm로 하는 것이 적당하다. 이러한 점을 감안하여 곡률반경을 1.2~4.5mm로 하였더니 적절하였다. 즉, 상기 스트랩(110)에 형성된 각각의 절곡부위의 곡률반경을 1.2mm보다 작게 하면 RF 로드(32)가 열팽창할 때에 절곡부위가 과하게 펴지므로 다시 원상태의 절곡 형상으로 복원되고 다시 펴지는 과정을 반복함에 따라 절곡부위가 쉽게 파손될 수 있다. 그리고, 스트랩(110)의 중간(113) 길이를 1cm로 하면 절곡부위의 최대 곡률반경은 4.5mm로 하는 것이 적당하다. Here, the two bends (114, 115) is a portion that is unfolded as the RF rod 32 is extended by thermal expansion, it should have a sufficient radius of curvature (R). Typically, the length of the shaft 10 of the ceramic heater used in the plasma reaction chamber in semiconductor manufacturing is approximately 17 cm, and accordingly penetrates the RF rod 32 through the shaft 10. In addition, the heater plate 20 is typically heated to approximately 550 ° C. Also, as in the embodiment of the present invention,

When the strap 110 is formed to be mounted on the shaft 10 in consideration of the size of the shaft 10, the length of the middle 113 of the strap 110 is approximately 1 cm. In consideration of these points, the radius of curvature was 1.2 to 4.5 mm, which was appropriate. That is, if the radius of curvature of each bent portion formed on the strap 110 is less than 1.2mm, the bent portion is excessively stretched when the RF rod 32 is thermally expanded, thereby restoring to the original bent shape and refolding the process. By repeating, the bent portion can be easily broken. When the length of the middle 113 of the strap 110 is 1 cm, the maximum radius of curvature of the bent portion is appropriately 4.5 mm.

On the other hand, the strap 110 is typically made of beryllium copper (beryllium copper) material. In addition, according to the present invention, the strap 110 should be durable against repeated bending while bending the bent portion well. Applicant repeatedly experimented in view of such materials and requirements, it was appropriate to manufacture the thickness (t) of the strap 110 to 0.1 ~ 0.4mm. In other words, if the thickness is less than 0.1mm bends so well that it is uncomfortable and there is a risk of arcing when mounting by bolt fastening, if the thickness is greater than 0.4mm it is not easy to bend at the bent portion was easy to cut.

In addition, screw holes 116 and 117 are formed at the upper end 111 and the lower end 112 of the strap 110 to penetrate the bolts 140 and 141, respectively, and penetrate the bolt 140 through the upper end 111. The upper end 111 is fixed by screwing into the screw groove 232 of the strap fixing groove 230 to be described later, and the female thread groove 133 of the clamp 130 by penetrating the bolt 141 through the lower end 112. The bottom can be fixed by screwing it in.

Here, the screw holes (116, 117) is larger than the width (L1) up and down length (L2), so as to tighten the bolts by pressing the upper and lower ends of the strap 110 with the bolt head clamp 130 or Even in close contact with the strap fixing groove 230 to allow the flow for thermal expansion. Of course, the width (L1) of the screw holes (116, 117) has a value to slightly penetrate the threaded portion of the bolt.

The insulating case 120, the clamp 130 is not directly in contact with the inner surface of the mounting groove 200, the lower end 112 and the middle 113 except for the upper end 111 in the strap 110 is also As a case to directly contact the inner surface of the mounting groove 200, the shape of the cover groove 200 to cover the inner surface of the strap insertion groove 210 and the clamp insertion groove 220 described below to a certain thickness, that is, The inner surface of the strap insertion groove 210 and the clamp insertion groove 220 is formed to have an inner space.

In addition, the inner space of the insulating case 120 is formed to have only a space for inserting the clamp 130 and the strap 110. 5, the clamp insertion space 121 for inserting the clamp 130 from the bottom to the upper portion and the strap insertion space for inserting the strap 110 from the side ( 122) is formed to be connected to each other, but to reduce the margin of space as much as possible, to be mounted while touching the surface of the interference insert or the interior space.

Here, the clamp insertion space 121 is a surface in which the through-hole 134 is formed in the clamp 130, that is, the surface that is fixed in contact with the bottom surface of the strap 110 to the outer peripheral surface of the shaft 10 and At the same time, by allowing the outside of the strap insertion space 122 to look outward, the lower end of the strap 110 inserted into the strap insertion space 122 can be fixed at the same time as the insertion. Of course, the strap insertion space 122 is in surface contact with the middle 113 of the strap 110 and the inner top and bottom height of the strap insertion space 122 is greater than the height of the bottom 112 of the strap 110. The strap 110 may be inserted so as not to be exposed to the outside. In addition, a hole 123 through which the RF rod 32 penetrates is formed on the upper surface of the clamp insertion space 121.

The mounting groove 200 is a space for mounting the ground connector 100 configured as described above. The clamp is fixed to be used as a mounting space of the clamp 130 by cutting around the lower end of the RF rod 32. Longest incision toward the clamp fixing groove 220 in the groove 220, the outer surface of the shaft 10, but cut to have a width enough to insert the strap 110, the upper end 111 of the strap 110 A strap insertion groove 210 is used as an insertion space of the portion except for forming the inner upper surface to match the shape of the middle 113 of the strap 110, and in the form of a groove in the upper outer surface at the inlet of the strap insertion groove 210 Incision is made of a strap fixing groove 230, which is used as a space for fixing the top of the strap 110 by having a width to insert the top of the strap 110.

Here, the strap fixing groove 230 is formed to be much lower than the strap insertion groove 210, and after the upper end 111 of the strap 110 is inserted into the bolt 141 is fixed by screwing, bolt ( The screw groove 232 for screwing the 141 is formed, and is formed to have a depth that does not protrude from the outer surface of the shaft 10 of the screwed bolt 141.

In addition, referring to Figure 4, the part where the strap fixing groove 230 and the strap insertion groove 210 meets the step is formed, the edge 231 by the step is not left at right angles to each other No, chamfer. That is, the edge 231 is to chamfer not to touch the portion of the bend 114 between the top and the middle of the strap 110. This is, when repeating the shape change to restore the bending state to the bent 114 back to the bent state, if the repeated operation falling to the inner surface of the strap fixing groove 230 that is not covered with the insulating case 120 This is because arcing can occur and corrode. In addition, the chamfering of the edge 231 is preferably started at the point where the end of the pressing portion of the bolt head of the bolt 140 from the upper end 111 of the strap (110).

Since the bend 115 between the lower end 112 and the middle 113 in the strap 110 is inside the insulating case 120, it does not touch the inner surface of the mounting groove 200 formed in the shaft 10.

The clamp fixing groove 220 and the strap insertion groove 210 except for the strap fixing groove 230 have an inner surface covered by the insulating case 120, and thus the clamp in the state of covering the insulating case 120. 130 and the size to which the strap 110 can be mounted, that is, formed to match the shape of the outer surface of the insulating case 120. In addition, the strap insertion groove 210 and the strap fixing groove 230 are incision width is determined in accordance with the width of the strap 110 formed in the form of a band and the thickness of the inside and outside of the insulating case 120. Here, the mounting groove 200 is open to the bottom, it is inserted into the mounting groove 200 in a manner to push the insulating case 120 toward the upper portion.

As described above, the mounting groove 200 formed according to the embodiment of the present invention mounts the strap 110 and the clamp 130 in a state in which a portion of the inner surface is thinly covered by the insulating case 120. When viewed from the bottom, the clamp insertion groove 220 is inserted around the bottom of the RF rod 32 to insert the clamp 130 to fit snugly from the bottom, when viewed from the side, the bottom of the strap 110 While the strap insertion groove 210 that can be inserted into the vertical fitting state 112 is vertically cut to be formed to follow the clamp insertion groove 220, the strap fixing groove on the upper side of the inlet of the strap insertion groove 210 is formed. By forming the 220, the mounting space of the clamp 130 and the strap 110 can be reduced to a minimum. Accordingly, the portion occupied by the mounting groove 200 for mounting the ground connector 100 at the lower end of the shaft 10 can be reduced to the maximum, so that the thermocouple insertion passage 13 and the coolant are injected / discharged. The ground groove 100 may be installed by forming the mounting groove 200 in the shaft 10 having a cooling water passage 14 to allow only a narrow space.

In addition, the ground connector 100 mounted in the mounting groove 200 extends the strap 110 when the RF rod 32 is thermally expanded to reduce the fatigue strength at the bent portion. This will be described in detail with reference to FIG. 7.

FIG. 7 is a side view illustrating a shape change of the strap 110 according to thermal expansion of the RF rod 32. The state before thermal expansion is illustrated in FIG. 7A, and the state after thermal expansion is illustrated in FIG. 7B. In FIG. 7B, the RF rod 32 is excessively stretched relative to the size of the strap 110 in order to visually see the shape change of the strap 110.

As shown in FIG. 7A, the strap 110 is bolted to the ground 111 at the upper end 111 and the lower end 112 is bolted to the clamp 130 mounted to the RF rod 32. do. When the RF rod 32 thermally expands, as shown in FIG. 7B, the clamp 130 mounted at the lower end of the RF rod 32 moves downward by the extension of the RF rod. At this time, the bending (114, 115) of the strap 110 is deformed in a state before bending, that is, in the form of bending in the manufacturing process, the middle 113 between the two bending (114, 115) is slightly inclined. That is, since each of the bends 114 and 115 formed in the strap 110 is deformed in the form of being stretched according to the thermal expansion of the RF rod 32, the bending 110 is less fatigued than the case of the bent form. Therefore, according to the present invention, it is possible to increase the durability of the strap 110.

On the other hand, the number of bending of the strap 110 is not limited to two times as shown in the accompanying drawings in the embodiment of the present invention, may be bent more than two times. That is, you may bend twice or more. As described above, when the strap 110 is bent more than two times, the strap 110 has a step shape, and the angle of the bent portion is perpendicular or obtuse. When the angle of the bent portion is an obtuse angle, it is not bent below the horizontal plane, but when viewed in the vertical plane, the strap 110 is flattened so as to be deflected to the outer surface of the shaft 10. In addition, an insulation case is manufactured in the middle of the strap 110, that is, before the thermal expansion of the portion except for the top and the bottom fixed by the bolt. Here, the upper and lower ends of the strap 110 may be erected vertically for ease of mounting.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, . ≪ / RTI > Accordingly, such modifications are deemed to be within the scope of the present invention, and the scope of the present invention should be determined by the following claims.

Reference Signs List 1 chamber 2 substrate 3 heater power 4 electrode power
10 shaft 11 heater insertion passage 12 RF rod insertion passage
13: thermocouple insertion passage 14: cooling water passage
20: heater plate 21: heater element 22: RF electrode
30: rod 31: heater rod 32: RF rod
100: Grounding connector
110: strap 111: top 112: bottom
113: middle 114,115: bending 116,117: screw hole
120: insulation case
121: clamp insertion space 122: strap insertion space
130: clamp 131: rod through hole 132: incision
133: female thread groove 134: through hole 135: body portion
136: tightening
140, 141: Bolt
200: mounting groove
210: strap insertion groove 220: clamp insertion groove 230: strap fixing groove

Claims (7)

delete A heater plate 20 configured to apply heat to a substrate accommodated in a plasma reaction chamber and mounted on an upper surface thereof, and to include an RF electrode 22 for generating plasma;
It is mounted on the bottom of the heater plate 20, and accommodates the RF rod 32 which is electrically connected to the RF electrode 22 to penetrate up and down therein, and is cut in the lower side toward the RF rod 32. A shaft 10 electrically connected to the RF rod 32 by mounting the ground connector 100 in the mounting groove 200 after the mounting groove 200 is formed;
In the ceramic heater comprising a,
The ground connector 100,
A clamp 130 mounted on the RF rod 32 exposed inside the mounting groove 200;
It is formed of a conductive strip vertically formed and inserted into the mounting groove 200, while bending the middle part twice in a state where the bottom is vertically fixed to the clamp 130, the angle of the first bending following the bottom of the shaft ( 10) orthogonal or obtuse to the outside, and after forming the second bend so that the upper end fixed to the shaft is directed in the vertical direction, the upper end is fixed closer to the outer surface of the shaft 10 so that the upper end is higher than the lower end. A strap 110 configured to be fixed to the outside and to form a curvature of the bent portion so that the bent portion is extended when the RF rod 32 is thermally expanded to move downward in a downward direction;
Ceramic heater with a strap for grounding, characterized in that it comprises a. The method of claim 2,
The mounting groove 200,
With a step according to the second bent shape of the strap 110 is in close contact with the strap 110, provided with a grounding strap characterized in that the chamfering (chamfering) so as not to touch the second bend of the strap 110 Ceramic heater. The method of claim 3,
The strap 110 is a beryllium copper material having a shape of a band having a thickness of 0.1 ~ 0.4mm, the ceramic having a strap for grounding, characterized in that the curvature radius of the bent portion is formed to 1.2 ~ 4.5mm heater. The method of claim 3,
The strap 110 is fixed to the clamp 130 and the shaft 10 by fastening bolts by forming screw holes 116 and 117 to penetrate the bolts 140 and 141 at upper and lower ends, respectively.
The screw hole (116, 117) is a ceramic heater having a strap for grounding, characterized in that it is formed longer than the width. The method of claim 3,
The mounting groove 200,
The insulating case 120 is attached to the surface except the surface on which the upper end of the strap 110 is fixed, so that the RF rod 32 does not directly contact the shaft 10, and the strap 110 A ceramic heater having a grounding strap, except for the upper portion of the clamp and the clamp 130 to be mounted inside the insulating case 120. The method of claim 3,
The mounting groove 200,
Ceramic heater having a strap for grounding, characterized in that it is formed to have a passage for pushing the lower end of the strap 110 in the surface contact direction with the clamp 130.

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