Wafer holder

Abstract

A wafer holder and processing apparatus to be attached to a vacuum wafer processing chamber, comprising: a base device having an annular surface; a circular metal wafer transport plate mounted on the center of a drive shaft centered with respect to the center of the annular surface, wherein the drive shaft and the transport plate are rotatable around a rotation axis Z relative to the base device and supported by the base device via the center of the annular surface; a dynamic vacuum seal configuration operably connected to the drive shaft; and a critical distance d that is lockably attached to the drive shaft and rotatably supported by an element of the base device, or rotatably supported within or on the floor surface of the processing chamber. c A critical distance d comprises an axial distance setting device configured to set a critical distance d c A wafer holder and processing apparatus defined as the distance in a direction parallel to axis Z between the annular surface of a base device and one surface of a circular metal wafer transport plate facing the base device and parallel to the annular surface.

Description

[Technical Field]

[0001] The present invention relates to a wafer holder and processing apparatus, a vacuum processing apparatus, and the critical distance d between a base apparatus and a rotatable circular metal wafer transport plate. c This invention relates to a method for setting the nominal value of a rotary drive shaft and a vacuum feedthrough. [Background technology]

[0002] Various embodiments of wafer holders and processing apparatus for high-temperature applications are known from the prior art, such as Patent Document 1 of the present applicant. Such wafer holders and processing apparatus, hereafter referred to as chucks, function well as long as manufacturing tolerances of a few tens of millimeters of the relevant assembly chuck elements do not affect the specific system characteristics of the chuck. However, if specific characteristics of the chuck, such as RF drive and capacitive coupling capacitance, depend on such small tolerances due to a large number of assembly elements, large variations in the desired characteristics can occur. Therefore, the present invention discloses a chuck in which the allowable deviation from geometric nominal values ​​important to specific characteristics of the assembly chuck can be easily adjusted.

[0003] Definition: As used herein, “annular surface” includes annular and disc-shaped surfaces having a central hole for accommodating functional elements such as fastening means, different types of wafer supports for lifting wafers, media, or through holes for measurement, and annular and disc-shaped surfaces that are elongated radially or interspersed by recesses which may be arranged radially symmetrically along the radius within the annular surface.

[0004] Each definition also applies to terms such as “circumferential plane, frame, surface,” boundary, shield, or nose, which include intermittent structures.

[0005] The term "circular wafer transport plate" also has a corresponding definition, which includes disc-shaped transport plates with or without central holes such as a central back gas inlet, and, as an example, circular plates divided by the recesses described above.

[0006] A "dynamic vacuum seal," also known below as a dynamic seal or dynamic gasket, is a vacuum seal for sealing feedthroughs, particularly rotational feedthroughs of elements that move or are moved in a partially vacuum and partially atmospheric environment. Examples include dynamic seals for sealing rotating shafts and dynamic gaskets for sealing linearly moving components such as linear shutters.

[0007] In this specification, “substantially planar surface” means a planar surface which may further include electrical connectors, display or measurement windows, and recesses or sockets for holding specific elements within, on, or on the planar surface. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] International Publication No. 2013 / 030190 [Overview of the project] [Problems that the invention aims to solve]

[0009] An object of the present invention is to provide a chuck, for example, a rotary chuck that can be easily and accurately mounted. A further object of the present invention is to provide an assembly chuck that allows for the measurement of specific geometric parameters as needed and sets those parameters to nominal values ​​by predetermined adjustment operations in order to adjust them. A further object of the present invention is to set specific characteristics of the chuck by the aforementioned adjustment operations. For example, an object of the present invention is to provide a means for easily and accurately setting the capacity of an RF chuck by adjusting the distance between the base device and an electrically insulated wafer transport plate, i.e., the distance between the surface of the base device and the wafer transport plate that determines the capacity. A further object of the present invention is to provide a means for accurately positioning a rotating component in a vacuum processing chamber relative to the chamber or a specific static installation within the processing chamber. [Means for solving the problem]

[0010] According to the present invention, at least one of these problems is solved by the wafer holder and processing apparatus described in claim 1, the vacuum processing apparatus described in claim 19, the method according to claim 20, and the rotary drive shaft and vacuum feedthrough described in claim 22.

[0011] At least some of these problems are solved by an inventive embodiment of a wafer holder and processing apparatus, also known as a chuck and hereinafter referred to as a chuck, which is attached to a vacuum wafer processing chamber. This wafer holder and processing apparatus (chuck) is - A stand device having an annular surface, -A circular metal wafer transport plate mounted on the center of a drive shaft centered with respect to the center of an annular surface, wherein the drive shaft and the transport plate are rotatable around a rotation axis Z relative to the base device and supported by the base device, via the center of the annular surface, - A dynamic vacuum seal configuration operably connected to the drive shaft, - It is configured to be rotatably mounted on a drive shaft and supported on an element of a platform, such as the inner circumferential frame or nose of a bottom plate, part of a dynamic vacuum seal configuration, or within or on the floor surface of a processing chamber, for example, on a circular surface around a through-hole in the floor surface or on the inner circumferential frame or nose around a through-hole, with a critical distance d c An axial distance setting device for setting distances, characterized in that, in order to improve the sliding characteristics of the distance setting device, the entire device or the contact area of ​​the supported device is made of metal bearings, or a dry sliding layer such as a coating is provided. Equipped with, -critical distance d c This is defined as the distance in a direction parallel to axis Z between the annular surface of the base device and one surface of a circular metal wafer transport plate facing the base device and parallel to the annular surface, and one surface of the wafer transport plate may have a further annular surface region that overlaps with the annular surface in the Z projection, and the annular surface and one surface of the wafer transport plate may be horizontal with respect to the horizontal plane or inclined plane surfaces.

[0012] The wafer holder and the base device of the processing apparatus may further include a substantially planar extended surface adjacent to a peripheral frame that forms an annular surface and protrudes in a direction toward one surface of the wafer transfer plate.

[0013] The frame further includes an inner peripheral frame surface that protrudes adjacent to the substantially planar surface, and all of the surface of the wafer transfer plate facing the base device, the substantially planar extended surface, and the inner frame surface define a heater chamber, and the heater chamber is disposed in the heater chamber along the substantially planar extended surface and along one surface of the circular metal wafer transfer plate, and may include a number of heater lamp tubes directed toward one surface of the circular metal wafer transfer plate and attached to the base device.

[0014] The wafer holder and the processing apparatus may further include a wafer holding device operably coupled to the circular metal wafer transfer plate.

[0015] The wafer holder and the processing apparatus can include at least three wafer support portions that are attached so as to be extendable and retractable from or to an annular surface, and thus the annular surface can be divided into at least three separation surfaces, for example, the end faces of the frame. Thereby, the upper part of the inner peripheral frame surface with respect to at least the lower bottom surface can also be divided into the end faces of three main separate frames. The wafer support portions may include pin-shaped or radially oriented elongated effector heads, and the elongated effector heads are provided with steps and / or inclined portions and support regions on or near the wafer support surface of the effector head to center the wafer during movement and hold it in a predetermined position during processing. In this case, a slit corresponding to the circular metal wafer transfer plate is provided to allow the wafer support portions to pass through, and the wafer is lifted and lowered by the wafer transfer plate. The wafer transfer plate can be rotated for heating, for example, together with the wafer or alone, only when the wafer support portions are contracted within the annular surface or when they are fully extended. Therefore, the wafer support portions can be arranged such that the wafer support surface of the effector substantially protrudes within the diameter of the wafer transfer surface of the wafer transfer plate, while the rod to which the effector head is attached for vertical movement is arranged outside the projection range of the rotary transfer plate. The wafer holder and the processing apparatus can be provided with means for aligning the slit and the wafer support portions.

[0016] The wafer holder and the processing apparatus may further include a bottom plate, and the bottom plate may include an annular surface and a dynamic vacuum seal configuration that surrounds the sealing surface of the drive shaft of the wafer transfer plate during operation. The distance setting device can be operably and rotatably supported on an element of the bottom plate, for example, the inner peripheral frame or nose of the bottom plate, or an element of the dynamic vacuum seal configuration, for example, the housing of the dynamic seal configuration that can be a ferromagnetic fluid seal configuration. The bottom plate can be manufactured integrally with the frame or separately.

[0017] In a further inventive embodiment, the chuck distance setting device may comprise a hollow body with vertical slots or divisions, specifically, a hollow body with vertical slots or divisions parallel to the central axis Z' of the hollow body, the hollow body being formed from a bearing alloy, or at least a dry sliding surface provided on the surface region of the hollow body, for example, by coating. By providing slots, the elasticity of the metal body is utilized to expand the width of the slots, expanding the inner diameter of the distance setting device after it has been mounted on the shaft during the installation process, allowing the distance setting device to be moved quickly and easily to a preliminary shaft position in the intermediate region of the fine thread, where it can be returned to the shaft and tightened. Thereafter, a precise position can be set using the fine thread and a locking mechanism described later. Alternatively, the distance setting device may be configured as a two-part hollow body divided into two nut-shaped parts by a continuous slot, and each can be mounted on the shaft by two locking mechanisms, which may be similar or separately configured. The hollow body has a continuous slot or a divided nut shape, and when mounted on the drive shaft in the operating position, a sliding surface may be formed on the lower surface region. The slotted hollow body comprises a female fine thread that cooperates with the fine thread of the drive shaft on the outer diameter of the drive shaft, and a locking mechanism that connects the slotted body to the fine thread of the drive shaft and locks or unlocks it thereon. Details of the locking mechanism that locks the final position of the distance setting device on the drive shaft will be described later. The bearing alloy may be bronze, tin bronze, lead bronze, or other metal bearings, which may also be provided as a coating. Other dry sliding coatings include hard carbon or diamond-like carbon (DLC) coatings, such as aC, aC:H, ta-C, ta-C:H, aC:Me, aC:H:Me, aC:H:X, where X represents Si, O, N, F, or B. Such coatings may be provided on at least a supported contact area, for example, part or all of the circumferential area of ​​the front surface of the distance setting device.

[0018] The locking mechanism may include at least one threaded connection, for example, on both sides of a hollow body adjacent to the slot, i.e., between the two sides of the slot, and a threaded connection parallel to the outside of the fine thread diameter or projection of the fine thread and the tangent to the fine thread diameter.

[0019] In a slotted or segmented hollow body, a spring and snap-in ball assembly can be provided within the radial bore of the body having an opening in the Z' axis direction, cooperating, for example, with an elongated axial groove provided on the outer diameter of the drive shaft, either below or above the fine thread in the axial direction. This cooperation can be performed by rotating the slotted hollow body on the drive shaft, and the pushing / pushing of a portion of the spring-loaded ball into / out of the groove through the opening during the screwing operation allows for snap-in / snap-out. When the slotted hollow body is on the drive shaft and the spring-loaded ball snaps in at a new position relative to the nominal distance to be set, the position can be locked by the screw connection. Fine threads, usable for typical shaft diameters of 20 to 50 mm, move the slotted body connected by the fine thread in the opposite direction to the axial direction when the thread rotates 360° once, achieving the respective properly adjusted settings. By providing 10 elongated, axially oriented grooves at equal intervals on the outer diameter of the drive shaft, the step size is set to 0.1 mm, specifically, snap-like movement from one position to the next. The length of the grooves defines the height that allows for precise axial adjustment.

[0020] In a further inventive embodiment, the circular metal wafer transport plate of the chuck can be electrically insulated from the base device and configured to be electrically connected to, for example, an electrical bias source via the base device, or preferably capacitively coupled. Thus, an electrical insulator can be placed between the drive shaft and the transport plate, and the circumferential region of the surface facing the base device, which can become a further annular region overlapping with the annular region of the base device in the axial projection, can be positioned parallel to at least a portion of the annular surface of the base device, and both the circumferential region and the annular surface have a critical distance d cThis allows for the formation of an essentially circumferential planar capacitor with a defined capacitive gap.

[0021] In a further embodiment, the wafer holder and processing apparatus may include gas discharge and supply devices along and via the wafer transport surface, which is the other side of the wafer transport plate. The gas discharge and supply devices can be operated / fluidically connected at the central gas inlet of the drive shaft.

[0022] In a further embodiment of the present invention, the chuck's transport plate may include a double-walled sleeve cup, in which the outer cup wall is mounted on or at the center point of the surface facing the base device, and the inner cup wall is mounted on the head of the drive shaft, electrically insulated. This allows the sleeve cup, which constitutes part of the drive head, to have a central gas passage leading from the central gas inlet of the drive shaft to a gas discharge and supply device. The passage has or is formed to have an opening toward the gap between the double walls, thereby creating a vacuum in the double walls, forming a thermal barrier during the vacuum processing process, and isolating the shaft from the heat load from the heater chamber.

[0023] The head of the drive shaft may have two parallel flanges that overlap each other in the Z projection and point toward different ends of the drive shaft, each flange having at least one insulator attached, and further comprising a fixing element for attaching the sleeve cup to the drive shaft. For example, the fixing element may include a clamp or screws for attaching the head and insulator arrangement to the inner bottom of the sleeve cup. Additional insulating bushings may be provided in the screw holes of the head and the metal mounting ring or corresponding washer to prevent mechanical overload when the ceramic insulator is attached. Such a configuration can also be used when the drive shaft is attached directly to the wafer transport plate without using a double-walled sleeve cup.

[0024] Furthermore, an inner heat shield can be provided around the drive shaft and / or sleeve cup to form a reflector and heat shield to protect the drive shaft from the heat of the lamp in the heater chamber.

[0025] In a further embodiment, a wafer holder and processing apparatus, or a corresponding processing chamber or processing system including the processing apparatus, includes an electrical or corresponding process power control unit configured to control power to a plurality of heater lamp tubes and to operate the plurality of heater lamp tubes to determine a predetermined temperature averaged on one surface and the other surface opposite to the wafer transport surface of a circular metal wafer transport plate.

[0026] One aspect of the present invention can be combined with either of the preceding or succeeding aspects, as long as it does not contradict the present invention, and the plurality of heater lamp tubes consist of a plurality of identical heater lamp tubes mounted in the heater chamber, oriented equally radially from the center to the circular frame surface. In a further embodiment, the longitudinal direction of the heater lamp tubes is offset with respect to the radial angle from the center of the substantially planar surface facing the protruding circular frame surface.

[0027] In a further embodiment that can be combined with either of the embodiments described above, as long as it does not contradict the previous or subsequent embodiments, the position of at least a portion of the heater lamp tubes can be adjusted within the heater chamber, and the temperature distribution along the wafer can be optimized by placing it on a circular metal wafer transport plate and rotating with it, i.e., rotating relative to the heater lamp tubes.

[0028] In a further embodiment, which can be combined with either of the embodiments described above, to the extent that they do not contradict each other, the heater lamp tube has a thickness that encloses a heater chamber between a substantially extended planar surface and one surface of a circular metal wafer transport plate without contacting these surfaces. In other words, the thickness of the heater chamber is substantially enclosed by the range of the thickness of the heater lamp tube.

[0029] More specifically, in the wafer holder and temperature control device of the present invention, and in certain embodiments that can be combined with any of the above embodiments as long as they do not conflict, the wafer transport plate is, for example, A wafer with a diameter of 100 mm, comprising multiple heater lamp tubes consisting of three 540W infrared radiating lamp tubes, A wafer with a diameter of 150 mm, comprising the aforementioned multiple tubes consisting of three 540W infrared radiation lamp tubes, A wafer with a diameter of 200 mm, comprising the aforementioned multiple tubes consisting of three 540W infrared radiation lamp tubes, It consists of one of the following.

[0030] In a further embodiment that can be combined with either of the embodiments described above, as long as it does not contradict the other, a fluid line device is provided within the stand device for circulating a fluid, for example, a coolant to cool the processed wafers as needed.

[0031] In a further embodiment of the present invention, the wafer holder may be a weight ring sized to be positioned around the periphery of the wafer. Depending on the requirements of the process, the weight ring may be electrically connected to an electrical bias source, preferably capacitively coupled to a circular metal wafer transport by a region parallel to and opposite to a region beyond the wafer support region of the wafer transport, and / or capacitively coupled in an inner cylindrical region concentric with a region forming at least a portion of the substantial cylindrical surface on the outside of the wafer transport. Alternatively and / or additionally, the weight ring may be capacitively coupled beyond the annular surface of the base device by a region parallel to and opposite to a planar or cylindrical region of the base device, respectively.

[0032] The present invention further relates to a vacuum processing apparatus comprising the wafer holder and processing apparatus detailed above, wherein the apparatus may include a vacuum pump device, at least one target, and a target shutter for separating the target from the processing space between the target and the wafer transport surface. In the case of multiple targets, for example, two or three targets mounted on a rotatable or swivelable dome or carrot structure, common or individual target shutters can be used. Optionally, all available targets and target shutters can be separated from the processing space at once using a single, for example, preferably linear process shutter.

[0033] The present invention further relates to a critical distance d between the chuck base device and the rotatable circular metal wafer transport plate of the chuck. c A method for setting a nominal value, for example, for performing a vacuum heat treatment and / or vacuum deposition process using a wafer, wherein an axial distance setting device configured to correct a predetermined difference, for example, each distance value in equally spaced steps, is used. -distance d c This is defined as the shortest possible distance in a direction parallel to the Z-axis between a base device, for example, an annular surface of the base device and one surface, for example, a further annular surface region of a circular metal wafer transport plate facing the base device and / or a corresponding radially expanding surface of an element facing the base device, which is mounted on the transport plate and rotates with the transport plate (for example, such an element may be electrically connected to the transport plate, for example, a metal weight ring), - The stand device comprises at least a substantial annular surface, - The wafer transport plate is positioned at the center of a drive shaft that is rotatable relative to the base device around a geometric axis passing through the center of the annular surface. - The distance setting device is mounted to the drive shaft in a lockable manner and is configured to be rotatably supported by an element of the base device or the housing of the dynamic vacuum seal, or within or on the bottom of the processing chamber. The above settings, which are performed in a predetermined order, - The distance d in a state where the wafer transfer plate is at a different position relative to the base device c is measured multiple times, and the average value d cA is calculated. If there is a difference compared to the nominal distance d cN , the distance value of at least one differential step defined in advance is incorporated to obtain the average distance d cA ; and - In a state where the drive shaft is coupled to position the wafer transfer plate, the drive shaft is removed together with the wafer transfer plate and the distance setting device from the base device, and finally from the drive device. Usually, the removal is performed from the base device in a state where the base device is installed on or within the floor of the vacuum processing chamber; - In the removed state, the average distance d cA is adjusted to the nominal distance d cN by the distance setting device, and the distance setting device is locked to the drive shaft; - The drive shaft is attached together with the wafer transfer plate and the distance setting device to the base device and the drive device; and at least includes

[0034] In the step of obtaining the average distance d cA , for example, a ring-shaped or cylindrical weight ring or dummy weight is installed on the circular wafer transfer plate, and a dynamic vacuum seal can be press-fitted to the load position against the reverse return of, for example, a magnetic fluid seal configuration.

[0035] The drive shaft forms a rotary module that can be easily attached and removed as a single unit from the base module in a pre-assembled state together with the wafer transfer plate and the distance setting device. As additional elements of the rotary module, those that can be pre-assembled as described above include a sleeve cup, an insulator, a fixing element, etc.

[0036] The present invention further relates to a rotary drive shaft having a vertical rotation axis Z', a shaft head, and a shaft base, and a vacuum feed-through. The drive shaft - has mounting means for mounting a transfer plate at the center of the head of the drive shaft; - A driving force transmission region provided at or near the base of the drive shaft, - An elongated sealing surface around the diameter of the drive shaft, which allows rotational and axial linear motion of the drive shaft for mounting the drive shaft to a dynamic vacuum seal, - The drive shaft's thread diameter is enclosed, and it is mounted to the drive shaft so as to be movable and lockable in the axial direction parallel to axis Z', and the axial distance setting device has a sliding surface on its lower surface to support the distance setting device and the drive shaft when locked. It is equipped with.

[0037] Therefore, the distance setting device may have a female thread that engages with a male thread in the region of the shaft's thread diameter. The distance setting device may further include a locking mechanism for locking the movement of the distance setting device on the drive shaft.

[0038] The rotary drive shaft has a graduated diameter adjacent to the thread diameter, and the graduated diameter has a circumferentially readable scale with elongated markings in the axial direction. The distance setting device may further comprise the graduated diameter and a scale scanning means, for example, a mechanical scale scanning means for stepwise setting the distance setting device from one marking to the next.

[0039] The features of the above embodiments of the apparatus / process can be used in any combination, as long as they do not contradict each other.

[0040] The embodiments of the present invention will be described in more detail below with reference to the drawings. These are for illustrative purposes only and should not be construed as intended to limit the technical scope. The drawings are as follows. [Brief explanation of the drawing]

[0041] [Figure 1] This is a schematic diagram of the chuck device. [Figure 2] This is a schematic diagram of a rotary capacitive coupling chuck device. [Figure 3] This is a schematic diagram of each hot chuck device. [Figure 4] This is a cross-sectional view of a capacitively coupled hot chuck device. [Figure 5] This is a top view of the stand-up device. [Figure 6] This diagram shows the changes in the capacity of the prior art chuck. [Figure 7] This is a schematic diagram of a vacuum processing device. [Figure 8] This is a top view of an inventive stand device. [Figure 9] This is a cross-sectional view of a capacitively coupled hot chuck device. [Figure 10] This diagram shows the change in capacity of an inventive chuck. [Figure 11A] This is a three-dimensional diagram of a slot-type hollow body made of bearing alloy. [Figure 11B] This is a three-dimensional diagram of a divided hollow body. [Figure 12] This is a three-dimensional diagram of an inventive drive shaft. [Figure 13] This is a three-dimensional cross-sectional view of the installed axial distance setting device. [Modes for carrying out the invention]

[0042] Figure 1 shows a schematic diagram of a prior art wafer holder and processing apparatus 1''. This apparatus is also called a chuck or chuck apparatus 1'' and comprises a chuck base 10 which constitutes or has a base plate 11 and a base plate 16, and a wafer transport plate 20 which has a wafer transport surface 21 for supporting a wafer 2. A bias supply device 50' supplies an arbitrary bias via a bias line 51 and can be useful for operating various vacuum processing processes such as etching and film deposition. The chuck 1'' in Figure 1 is a static chuck, and the chuck base 10 and the transport plate 20 are electrically insulated from each other by their respective insulating elements 9.

[0043] In contrast to Figure 1, the prior art chuck 1' shown in Figure 2 has a rotatable wafer transport plate 20 mounted on a rotary drive shaft 60' driven by a drive unit 90, for example, to optimize the layer thickness distribution during the film deposition process. Furthermore, the bias supply device is a high-frequency (HF) supply device 50. Since HF power is supplied substantially only through the surface of each conductor, and special consideration is required to uniformly supply power across the entire wafer transport surface 21, a simple central supply as shown in Figure 1 is difficult and can be further hindered by the rotary drive shaft 60'. Therefore, as shown in Figure 2, inductive coupling of HF power from the base plate 12 of the chuck base 10 to the wafer transport plate 20 is provided via a capacitive gap 9. In this case, the capacitive gap 9 is formed between an annular surface 14 including the entire plane 12 of the base plate 10 and each surface 22 facing the wafer transport plate 20 over the entire area A' of the overlapping surfaces. The distance between the two capacitively coupled opposing surfaces 14 and 22 is the critical distance d c While this is specified, the value should be kept as small as possible to increase the system capacity, at the same time, it must be a sufficient distance to avoid the risk of electrical short circuits between the rotating conveyor plate and the static platform device.

[0044] If a rotary chuck needs to provide additional functions such as heating and / or cooling, problems may arise with wafer handling / positioning and similar critical distances due to the increased complexity and number of individual components constituting the chuck, and thus the aforementioned mechanical and / or electrical problems may occur due to the accumulation of individual tolerances.

[0045] Figure 3 shows an inventive chuck comprising a heating element 41 within a heating chamber 40 defined by the surface 22 of a circular metal wafer transport plate facing the stand, the substantially planar extended surface 12 of the stand 10, and the inner circumferential frame surface 13 surrounding the planar surface 12. As a result, the annular surface 14 extends outward from the upper end of the inner circumferential frame surface 13 with respect to the central axis Z. The peripheral region A of the overlapping surfaces in Figure 3 is clearly smaller than region A' in Figure 2, and when the latter is used as a capacitor surface, a minimum gap and critical distance d are required to optimize the system capacitance. cTherefore, in this inventive embodiment shown in Figure 3, the critical distance d c To set this, an axial distance setting device 30 is installed, which is lockably attached to the drive shaft 60 and rotatably supported by a flange-like projection on the base 16.

[0046] Figure 4 shows a cross-section of a prior art capacitively coupled hot chuck apparatus 1'. Figure 5 shows a top view of the heater chamber 40 equipped with heater lamps 40 and wafer pins 3, excluding the wafer transport plate 20 of the chuck apparatus 1' shown in Figure 4. Figure 4 shows the nominal distances d1, d2, and d3 of the relevant capacitive gap values ​​that affect the capacitance between the surface 22 of the transport plate 20 and the opposing surfaces 14, 14' of the base apparatus, and between the surface 14' and the bottom surface 14'' of the recess that is approximately equal to the bottom surface of the insulator 52 installed thereon. The minimum gap distance d1 between the top surface 14' of the insulator 52 and the surface 22 is, here, the critical capacitance distance d cThe distance d2 is the distance of the "gap" between the two opposing sides of the insulator 52, which is equal to the axial thickness of the insulator and is used in the capacitance calculation below. The distance d3 is a further capacitive gap between surfaces 14 and 22, where the nominal distance d3 > d2. The tolerances Δd1 and Δd2 of each gap thickness d1 and d3, based on the tolerance Δd2 of the insulator thickness d2, are included in the following formula, so the tolerance of the critical gap distance in the assembled chuck is d1 ± 0.85 mm, where d1 is in the range of a few millimeters or less. Due to its large variation from the nominal gap value, the insulator 52 is positioned in the recess of the annular surface 14, oriented outward from the center defined by axis Z, to safely avoid electrical short circuits. The insulator 52 protrudes approximately 1 mm from the annular surface 14. Thus, in this case, surfaces 14 and 14' form the respective capacitive opposing surfaces of the corresponding annular region A'' of surface 22, as shown in Figure 4. On the other hand, surface 14'' forms the opposite surface of the second surface 14' of the insulator, and this also needs to be incorporated into the calculation formula below. Figures 4 and 5 show the three nominal distances d1, d2, and d3, including the thickness d2 of the insulator 52, and the nominal surface areas A1, A2, and A3 of the substantial annular surfaces 14', 14'', and 14 that define the above-mentioned geometry and nominal gap value. The details of the calculation formula are as follows:

[0047]

number

[0048] As can be seen from the formula, C1 refers to the capacitance of the gap between surface 14' and surface 22, and C2 refers to the capacitance of the insulation thickness between the bottom surface 14'' of the recess and surface 14' of the insulator 52. C1 and C2 are series capacitances and are in parallel with the capacitance C3 of the gap defined by the corresponding annular opposing surface regions of surface 14 and surface 22. Therefore, the total capacitance C totThe value of can vary by a multiple of approximately 4 due to predetermined dimensional variations, which is clearly insufficient. The typical capacity-to-gap distance d of each chuck in the prior art can be seen in Figure 6, and the variation in the capacity range due to the total system geometric tolerance Δd1-3 = ±0.85 mm = 1.7 mm is approximately 150 pF, and as explained above, the three distances d1 to d3 and the corresponding surface areas A1 to A3 contribute to the overall deviation.

[0049] Figure 7 shows a schematic diagram of a vacuum processing apparatus equipped with the inventive wafer holder or chuck described in Figure 3. The vacuum processing apparatus 5 comprises four magnetron sputtering stations 81, each station equipped with a target 83. The target axes T1 to T4 are oblique to the wafer transport plate 20 and symmetric with respect to axis Z. A spherical target shutter 84 with a target opening 86 is mounted in the center, i.e., on the Z axis, and is rotatable on the drive shutter shaft 85 of the system cover directly in front of the target 83, ensuring a clear view between the target in operation and the wafer being covered with the target material. Furthermore, a planar process shutter 87 is provided to completely close off the dome region 88 from the processing space 89.

[0050] The following describes further details and examples of inventive embodiments of the wafer holder. Figures 8 and 9 show an embodiment equipped with a heater chamber 40 suitable for high-temperature applications. Figure 8 shows a three-dimensional top view of the stand device 10 having an open heater chamber 40. The circumferential heat reflector 14-1 protrudes in the z direction from the outer diameter of the annular surface 14, and the critical distance d between the surface 22 of the wafer transport plate 20 facing the stand device and the annular surface 14 when installed. c The wafer transport plate is divided by measuring notches 14-2 provided for measurement (see Figure 9). Measurement can be easily performed, for example, using a caliper ruler. The recesses 14-3 receive wafer support pins 3 (see Figure 5) for lifting wafers from the (upper) wafer transport surface 21 of the wafer transport plate 20 and lowering wafers toward the wafer transport surface 21 of the wafer transport plate 20, and are provided to correspond to each notch 28 of the wafer transport plate (see also Figure 5).

[0051] Similar to the prior art shown in Figure 4, Figure 9 shows the critical distance d. c This shows that, in Figure 4, corresponds to d1. However, in this inventive embodiment, since the distance setting device 30 is used, there is no need to use an insulator 52 to avoid an electrical short circuit between the base device and the wafer transport plate, and there is no need to provide two capacitive gaps in the chuck as in Figure 4. In the embodiment shown in Figure 9, the critical distance between surfaces 14 and 22 is d c As shown in Figure 10, it is possible to set the capacitance C of the inventive chuck to ±0.1 mm or Δd = ±0.1 mm = 0.2 mm. This allows the variation in capacitance C of the inventive chuck to be set within a narrow range of ΔC = ±10 pF. This ensures not only positioning accuracy but also a uniform capacitance change per unit length, i.e., a uniform thickness d. c It was shown that this can be reduced by adopting a configuration that effectively creates a single effective capacity gap. Furthermore, the calculation details were simplified as follows, and the gap distance to be considered is essentially the critical gap distance d, which is related to the distance between the annular surface 14 and the corresponding opposing region of the surface 22 facing the base device. c There is only one.

[0052]

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[0053] The distance setting device 30 described in detail in the following embodiment sets the distance d c As can be seen in Figure 8, the only way to correct this is in 10 equal intervals of 0.1 mm is when a mismatch occurs that is measured through the measuring notch 14-2 of the heat reflector 14-1. The chuck 1 is assembled with a weight ring or a corresponding dummy weight to counteract the backflow of the dynamic vacuum seal 69, or magnetic fluid seal device in this case.

[0054] Figure 11A shows a stereoscopic view of an inventive distance setting device 30 comprising a slot-type hollow body 30, preferably made of a bearing alloy or having a dry sliding layer coated on the lower surface 39 of the main body 30. The slot-type hollow body 30 has a female fine thread 32, detailed in Figure 11B, in the area of ​​the threaded joint 31, and a threadless counterbore area 33' is provided within the counterbore sleeve 33. The spring 38' and snap-in ball 38'' (see also Figure 13) of the assembly 38 are provided in the radial bore 37 of the counterbore sleeve 33 of the main body 30, which has an opening, and the opening is oriented toward the center of the main body, i.e., in the direction of axis Z', when attached to the shaft 60. A retaining frame (not shown) may be provided on the inner circumference of the bore 37, which matches the diameter of the counterbore, so that only a portion of the ball is pushed out from the inner opening of the bore 37. A locking thread 36 is provided on one side of the slot 92 of the counterbore sleeve 33 of the main body 30, and a corresponding locking screw mounting portion 36' is provided on the other side of the slot 92. The two are aligned with each other substantially parallel to the tangent of the fine thread diameter (see Figure 11B), and the slot-type hollow body 30 is locked in the desired position using the locking screw 35. As a result, the slot-type hollow body 30 can be fixed to the drive shaft 60 by a locking mechanism 34 comprising the locking screw 35, the locking thread 36, and the screw mounting device 36' (see Figure 13). As shown in Figure 12, the fine thread 32 of the distance setting device 30 is configured to cooperate with the opposing fine thread 72 provided directly below the head 61 of the drive shaft 60.

[0055] Figure 11B shows a stereoscopic view of an alternative distance setting device 30 comprising two-part hollow bodies 30', 30'', preferably made of a bearing alloy or having a dry sliding layer coated on the lower surfaces 39 of the main bodies 30' and 30''. The two-part hollow bodies 30', 30'' have a configuration similar to the slot-type main body 30 of Figure 11A, and are provided with female fine threads 32 in the area of ​​the threaded joint 31, and have a threadless counterbore area 33' within the counterbore sleeve 33 and a corresponding radial bore 37 within the counterbore sleeve 33 of one of the main bodies 30'. A locking thread 36 is provided in the counterbore sleeve 33 of one of the main bodies 30', and a corresponding locking screw mount 36' is provided in the other body 30'', both arranged parallel to the tangent of the fine thread diameter and locking the first side ends of the main bodies 30', 30''. On the opposite side of the slot 92 that completely separates the half-nut bodies 30', 30'', a corresponding screw connection, or preferably a hinge (not shown), may be provided to hold the second side end.

[0056] The drive shaft 60 further includes a coupling portion 75 at the end opposite the head end for connection to the drive unit 90, either directly or by a power transmission device (not shown). Furthermore, a sealing surface 73 is provided on the diameter of the drive shaft 60, allowing rotational motion during installation and axially parallel linear motion for mounting the shaft to the dynamic vacuum seal 69. An elongated, axially extended groove 74 is provided on a further diameter of the drive shaft 60 adjacent to the opposing thread 72, cooperating with the balls 38'' of a snap-in ball assembly 38 located in the inner diameter portion of the counterbore 33. The distance setting device 30 is screwed into the thread to set the nominal distance d cAfter securing the ball, when it enters one of the grooves 74, the position of the distance setting device is locked by tightening the locking screw 70, thereby setting the nominal position shown in detail in Figure 13, the stereoscopic view showing the inventive axial distance setting device 30 incorporated into the base plate 11 of the corresponding chuck 1. The base plate 11 is provided with a protective wall 99 that further shields the drive head 61 in addition to providing thermal protection for the double-walled sleeve cup 67, the latter having an opening 79 that leads from the gas passage 77 to the gap 78 between each double wall of the sleeve cup. The double-walled sleeve cup 67 is electrically insulated from the drive shaft head 61 by screws 68 and an insulator 62. Subsequently, the wafer transport plate 20 is attached to the center of the upper part of the double-walled sleeve cup 67 by screws 68'. As shown in Figure 13, the sliding surface on the lower surface 39 of the body of the distance setting device 30 remains on the nose 66 of the housing 95 of the dynamic seal configuration 69.

[0057] As illustrated in Figures 11A, 11B, and 12, an inventive rotary drive shaft and vacuum feedthrough can consist solely of an axial distance setting device 30 and a drive shaft 60, and Figure 13 shows a corresponding mounting assembly for high-temperature applications and electrical insulation of a capacitively coupled RF chuck. [Explanation of symbols]

[0058] 1. Chuck device 2 wafers 3. Wafer support section (e.g., pin-shaped, pin-shaped with radially oriented effector head, or ring-shaped) 3' Wafer support surface 5. Vacuum Processing Equipment 6 Chamber Wall 7 Gas supply lines 8 Gas reservoir 9. Capacitive Gap 10 devices 11 base plate 11' Sub-base plate 12 Planar surfaces 13 Circular protruding frame surface 14 Annular surface 14' Second ring surface 14-1 Heat reflector 14-2 Measuring notch 14-3 Recess corresponding to notch 28 15th slot 16,16' base 17. Flange or projection of the base 20,20' wafer transport board 21 Wafer transport surface 22 Surfaces facing the devices 23 Surfaces facing the annular surface 28. Notches in wafer transport plates 29 slots 30 Distance setting device 31 Thread connection 32 Fine threads 33 Counterbore Sleeve 33' Counterbore (area) 34 Locking mechanism 35 Locking screw 36 Locking Threads 37 Radial bore 38 Snap-in Ball Assembly 38' spring 38'' ball 39. Bottom surface of the main unit 40 Heater Room 41 Heater lamp tube 42. Electrical connection (lamp tube) 50,50' bias supply device 51 Bias line 52 Electrical insulators 59 Shaft base 60 drive shaft 61 Drive shaft head 61' Drive shaft head (prior technology) 62 Electrical insulators 63 Sliding bearing level 63' Sliding bearing level (prior technology) 64. Sliding surface of the drive shaft Sliding surfaces of 65 devices 66 Slide Nose 67 Double-walled sleeve cup 68 screws 69 Dynamic Vacuum Seal 70 Vacuum seal 71 Gas feedthrough (drive shaft) 72 opposing threads 73 Sealing surface 74. Elongated axial grooves 75 Combined area 76 mounting holes 77 Passage section 78 gaps 79 Opening 81 Magnetron 83 Target 84-speed target shutter 85 Shutter shaft 86 Target opening 87 Process Shutter 88 Dome Area 89 Processing space 90 Drive unit 95 Magnetic Fluid Vacuum Seal Housing 97 Pump Room 98 pumps 99 Protective Wall Surfaces of the annular planes A, A1, A2, A3 T1, T3 target axes X,Y plane axis Z / Z' Vertical axis and central (rotational) axis (wafer transport plate / shaft, main body)

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