System for adjusting inclination and position of upper electrode

Abstract

To provide a system for adjusting the inclination and the position of an upper electrode.SOLUTION: The system for adjusting the inclination and the position of an upper electrode includes: an upper electrode module 11 facing a lower electrode module 13 in a step chamber (C); a lead 12 connected to the upper part of the step chamber (C); at least three motors 14a and 14b arranged in the upper surface of the lead 12; and connection means for connecting the at least three motors 14a and 14b and the upper electrode module 11 to each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a tilt and position adjustment system for an upper electrode, and more specifically, to a tilt and position adjustment system for an upper electrode capable of adjusting a process space by adjusting the position or tilt of the upper electrode with respect to a lower electrode.

Background Art

[0002] For the formation of a high integration density and high efficiency structure of semiconductor devices, the patterns are gradually becoming finer, thereby developing the performance for the manufacture of semiconductor devices through the application of various materials. With such development, as the patterns are gradually miniaturized and the structures become complex and deep, the number of overall processes and the difficulty level of each process are rapidly increasing. To progress with high-difficulty processes considering productivity, it is essential and indispensable to maintain and improve the wafer yield, whereby process factors such as the uniformity of the overall process, the production volume per unit time, and the formation of the process profile are emerging as the competitiveness of process equipment. Various semiconductor equipment manufacturers are making efforts in various developments of various fixed elements such as improving the temperature uniformity, adjusting the plasma density, and adjusting the sheath region to improve the said main performance. In particular, recently, in a situation where gradually more complex processes such as the use of different process gases in multiple etching stages within one process and the use of RF power outputs in various region bands are required, the limit points have become clear with conventional control knobs, and it can be said that the utilization of additional control knobs is inevitable. Regarding the improvement of process factors in the semiconductor manufacturing process, Patent Document 1 discloses a method for etching high aspect ratio features through a mask in a layer etched on a substrate. Also, Patent Document 2 discloses an RF power supplier and a matching network used in a plasma chamber. For improving the uniformity of process etching and controlling the process gap, for example, the distance between the upper electrode and the lower electrode or the spatial structure formed between the upper electrode or the lower electrode needs to be adjusted. However, the prior art or known technology does not disclose a technique capable of adjusting it.

[0003] The present invention is for solving the problems of the prior art and has the following objectives.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] An object of the present invention is to provide an adjustment system capable of adjusting the real-time position and inclination of an upper electrode by utilizing an electric motor, thereby improving the uniformity of process etching and serving as a control knob for controlling the etching profile through fixed gap control (Process Gap Control). [Means for Solving the Problems]

[0006] According to a suitable embodiment of the present invention, the inclination and position adjustment system of the upper electrode includes an upper electrode module disposed opposite to the lower electrode module of the process chamber; a lead coupled to the upper portion of the process chamber; at least three motors disposed on the upper surface of the lead; and coupling means for coupling at least three motors and the upper electrode module.

[0007] According to another suitable embodiment of the present invention, the inclination or vertical position of the upper electrode module is adjusted by the operation of the coupling means by at least three motors.

[0008] According to still another suitable embodiment of the present invention, the coupling means is coupled to the upper electrode module through an induction pipeline having a bellows structure.

[0009] According to still other suitable embodiments of the present invention, at least three motors are arranged separately from each other at the edge of the lead.

[0010] According to still other suitable embodiments of the present invention, at least three motors are arranged separately from each other at the central portion of the lead.

[0011] According to still other suitable embodiments of the present invention, at least three motors are connected to the upper electrode module by a connecting means through one induction hole.

[0012] According to still other suitable embodiments of the present invention, it includes a shower head arranged below the upper electrode module, and the shower head includes an inclined induction portion inclined outward.

[0013] According to still other suitable embodiments of the present invention, it further includes a purge gap formed on the peripheral surface of the upper electrode module.

[0014] According to still other suitable embodiments of the present invention, it further includes a ground ring coupled to the peripheral surface of the upper electrode module, and the ground ring includes a circular ring base and a plurality of flow holes formed along the ring base.

[0015] According to still other suitable embodiments of the present invention, the ground ring is elastic.

Advantages of the Invention

[0016] The adjustment system capable of adjusting the tilt and position of the upper electrode according to the present invention can function as an Etch Uniformity Control Knob. Specifically, when the adjustment system according to the present invention is configured to have a CCP (Capacitively Coupled Plasma) electrode for forming a uniform plasma density, it is designed so that the ground area of the upper electrode is maximized to expand the plasma region between the lower substrate and the electrode and make the plasma density uniform. Also, when the gas injection ports of the Shower Head are divided by area and a difference in gas injection occurs due to design characteristics, the Plasma Uniformity can be more easily adjusted by changing the additional gas ratio or adding Tuning Gas. In addition, various methods such as configuring a heater and a refrigerant line so that temperature adjustment by area is possible are being studied and used to maintain the temperature uniformity of the electrostatic chuck that fixes the lower substrate. In the case of the Etch Profile, it mainly occurs at the outer contour of the substrate and is deformed by various causes such as changes in gas flow due to exhaust, the formation of the inclination of the sheath area at the outer contour, and the temperature difference between the substrate and the Edge Ring. Thus, for controlling such a phenomenon, the shape of the upper outer contour electrode is designed to protrude compared to the inner main electrode for the purpose of deforming the inclination of the sheath region. And a flat sheath region is formed at the outer contour of the substrate. Further, the inclination of the lower sheath region is controlled through an accompanying operation of applying DC. Also, the material of the Edge Ring or Focus Ring existing at the outer contour of the lower substrate is made of the same silicon as the substrate material so that the wafer appears to be more widely opened, and the portion where the inclination of the actual sheath region occurs is moved in the Edge Ring direction so that the entire substrate becomes a flat sheath region. Furthermore, since the direction of the radical ions of the plasma can be changed by the temperature difference between the Edge Ring and the substrate, the temperature of the Edge Ring is compared with the substrate temperature and adjusted in a manner of raising or lowering according to the etching profile at the outer contour of the substrate.Through various methods like this, the uniformity of etching and program file control are carried out. However, when differences in process results occur, such as the deviation of the etching map due to design tolerances or manufacturing tolerances, the methods for correction are limited. In most cases, only circular adjustments can be made based on the substrate center, and methods for improving deviations on the left and right sides of the substrate are more restricted. The adjustment system according to the present invention enables real-time correction of the deviation of design tolerances or manufacturing tolerances. Specifically, a motor is used to form the tilt or vertical movement of the upper electrode in real time during the process, enabling control of uniformity or program files in various etching processes for each process or within a single process. Thereby, the adjustment system according to the present invention is applied as a main mediating variable for determining the process result and utilized as a real-time control knob.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0018] Hereinafter, the present invention will be described in detail with reference to the embodiments presented in the accompanying drawings. The embodiments are for a clear understanding of the present invention and the present invention is not limited thereto. In the following description, components having the same reference numerals in different drawings have similar functions, so repeated explanations will not be given if unnecessary for understanding the invention, and known components will be briefly described or omitted, but are not excluded from the embodiments of the present invention.

[0019] FIG. 1 illustrates an embodiment of an adjustment system capable of adjusting the tilt and position of an upper electrode according to the present invention.

[0020] Referring to FIG. 1, the tilt and position adjustment system of the upper electrode includes an upper electrode module 11 disposed opposite to the lower electrode module 13 of the process chamber (C); a lead 12 coupled to the upper portion of the process chamber (C); at least three motors 14a, 14b disposed on the upper surface of the lead 12; and coupling means for coupling the at least three motors 14a, 14b and the upper electrode module 11.

[0021] The process chamber (C) can become a vacuum chamber and can be a space where semiconductor processes such as an etching process on a wafer are performed by plasma. A lower electrode module 13 is disposed inside the process chamber (C) with an electrostatic chuck 131 positioned on the upper side. And an upper electrode module 11 is disposed above the process chamber (C) so as to face the lower electrode module 13. The lower electrode module 13 may include a lower electrode, an electrostatic chuck 131 disposed above the lower electrode; a heater 132 disposed inside the electrostatic chuck 131 to adjust the temperature of the wafer during the process; an edge ring 133; and an edge ring heater 134. RF power having different frequencies is applied to the lower electrode through a controller 17, and coolant may be supplied by a cooler 18 to maintain the temperature of the electrostatic chuck 131 within a predetermined range. Also, power is supplied via a filter unit 19 to operate the heater 132. A lead 12 is coupled to the upper side of the process chamber (C) to seal the process chamber (C), and the lead 12 can be disk-shaped and coupled to a frame block 121 surrounding the upper part of the process chamber (C). The upper electrode module 11 is disposed below the lead 12, and the upper electrode module 11 is structurally connected to at least three motors 14a, 14b disposed on the upper surface of the lead 12. Specifically, the vertical position of the upper electrode module 11 is adjusted or the inclination of the upper electrode module 11 is adjusted by the operation of at least three motors 14a, 14b. The lead 12 is disk-shaped, and at least three motors 14a, 14b are disposed at different positions on the upper surface of the lead 12. For example, the three motors 14a, 14b are separated and disposed along the edge of the lead 14a, 14b with a circumferential angle of 120°. Or the three motors 14a, 14b are disposed at the central portion of the lead 12 so as to have a circumferential angle of 120°. Induction holes 122 are formed in the lead 12 corresponding to each of the motors 14a, 14b, and operating shafts 141a, 141b flow into the interior of the chamber (C) through the induction holes 122.One end of the drive shafts 141a and 141b is connected to the motors 14a and 14b, and the other ends of the drive shafts 141a and 141b can be coupled to the upper surface of the upper electrode module 11. For example, pinion gears can be coupled to the respective motor shafts, and the drive shafts 141a and 141b can have a rack gear structure. Then, the drive shafts 141a and 141b can move up and down by the operation of the respective motors 14a and 14b. The motors 14a and 14b and the drive shafts 141a and 141b can be connected to each other in various ways to move the upper electrode module 11 up and down, and thus, the present invention is not limited thereto.

[0022] The induction hole 122 needs to be sealed with respect to the inside of the chamber (C). For this purpose, the induction pipelines 15a and 15b are formed in a form surrounding the induction hole 122, and the induction pipelines 15a and 15b may have a structure connecting the lower surface of the lead 12 and the upper surface of the upper electrode module 11. The induction pipelines 15a and 15b are composed of a structure having elasticity in the vertical direction, and may be composed of, for example, a bellows structure or a corrugated tube structure. Thereby, the vertical lengths of the induction pipelines 15a and 15b are adjusted by the elevation of the operating shafts 141a and 141b. The portions where the lower ends of the induction pipelines 15a and 15b contact the upper surface of the upper electrode module 11 are sealed by the sealing units 16a and 16b, and the induction pipelines 15a and 15b are blocked with respect to the inside of the chamber (C). A central hole (CH) is formed in the central portion of the lead 12, and a central induction pipeline 15c may be formed in the central hole (CH). The central induction pipeline 15c can have a structure similar to that of the induction pipelines 15a and 15b. The upper end of the central induction pipeline 15c contacts the lower surface of the lead 12, and the lower end of the central induction pipeline 15c may be coupled to the upper surface of the upper electrode module 11. A central sealing unit 16c may be formed at the portion where the lower end of the central induction pipeline 15c contacts the upper surface of the upper electrode module 11. Further, the central induction pipeline 15c is composed of a structure having elasticity in the vertical direction, and may be composed of, for example, a bellows structure or a corrugated tube structure. The cooling water line is induced to the upper electrode module 11 through the central induction pipeline 15c formed in this way. Also, a power line for supplying power to the heater unit disposed inside the upper electrode module 11 is induced, and the gas (G) is injected through the central induction pipeline 15c. Due to the structures of the induction pipelines 15a and 15b and the central induction pipeline 15c, the upper electrode module 11 can be moved up and down. The vertical position of the upper electrode module 11 is determined by at least three operating shafts 141a and 141b operated by at least three motors 14a and 14b, and the distance between the upper electrode module 11 and the lower electrode module 13 is adjusted. Also, the inclination of the upper electrode module 11 is adjusted by the elevation of at least one operating shaft 141a and 141b operated by at least one motor 14a and 14b.At least three motors 14a, 14b are variably arranged on the upper surface of the lead 12, whereby the present invention is not limited thereto.

[0023] FIG. 2 shows an embodiment of a motor arrangement structure for an adjustment system according to the present invention.

[0024] Referring to FIG. 2, three motors 14a, 14b, 14c are arranged separately from each other such that they have a circumferential angle of 120° at the edge portion of the lead 12. For each of the motors 14a, 14b, 14c in such an arrangement structure, induction holes must be formed in the lead 12, and three induction pipelines must be formed respectively based on the induction holes. In comparison, when three motors 14a, 14b, 14c are arranged at the central separation positions 21a, 21b, 21c, one central induction hole 22 is formed, and three operating shafts operated by the three motors 14a, 14b, 14c are arranged in the one central induction hole. Therefore, in one embodiment of the present invention, three motors 14a, 14b, 14c are arranged at the three central separation positions 21a, 21b, 21c. The three central separation positions 21a, 21b, 21c are arranged separately from each other along the edge of the central induction hole 22 so as to have a circumferential angle of 120°, and hereinafter, the present invention will be described based on such an arrangement structure. However, the number of motors 14a, 14b, 14c is three or more, and the present invention is not limited thereto.

[0025] FIG. 3 shows an embodiment of a central motor control structure in an adjustment system according to the present invention.

[0026] Referring to FIG. 3, three motors 14a and 14b are arranged at the central separation position, a central guiding hole 22 is formed at the center of the three motors 14a and 14b, and one guiding pipeline 15a can be formed based on the central guiding hole 22. The guiding pipeline 15a has a structure with elasticity in the vertical direction and can be, for example, of a bellows structure or a corrugated pipe structure. Also, a sealing unit 16a can be formed at the portion where the lower end of the guiding pipeline 15a is coupled to the upper surface of the upper electrode module 11. Actuating shafts 141a and 141b connected to the respective motors 14a and 14b extend along one guiding pipeline 15a having such a structure, and the lower ends of the respective actuating shafts 141a and 141b are in contact with the upper surface of the upper electrode module 11. A cooling water line (CL) is guided along the inside of the guiding pipeline 15a, and a heater line (HL) for supplying power to a heater 113 arranged in the upper electrode module 11 is guided to the upper electrode module 11 along the guiding pipeline 15a. A gas (G) for process progress is injected into the chamber through the guiding pipeline 15a. Also, a gas for purge is injected into the chamber through the purge hole (PH) formed in the lead 12 and through the upper surface of the upper electrode module 11. The upper electrode module 11 can be composed of a shower head 111 having an electrode function; a heater block 112 arranged above the shower head 111; a head heater 113 arranged on the upper surface of the shower head 111; and a plurality of cooling water paths 141_1 to 141_N arranged in the heater block 112. The upper surface of the upper electrode module 11 having such a structure can be moved up and down by contacting the lower ends of the three actuating shafts 141a and 141b at three different positions with respect to the center and at positions where the vertices of an equilateral triangle are formed. Also, the inclination of the upper electrode module 11 is adjusted by selectively operating the three actuating shafts 141a and 141b. The three motors 14a and 14b operate independently, whereby the three actuating shafts 141a and 141b can apply the same or different forces to different positions on the upper surface of the upper electrode module 11 independently. The vertical position or inclination of the upper electrode module 11 is determined by the forces applied by the three actuating shafts 141a and 141b.Accordingly, it is necessary to create means for measuring the force or the length of movement applied by the three operating shafts 141a and 141b. For example, the moving distances of the respective operating shafts 141a and 141b are detected by optical means by applying linear scalers. The relative distance of the upper electrode module 11 with respect to the lower electrode module is measured by the moving distances of the respective operating shafts 141a and 141b detected by the optical means, and at the same time, the parallel state of the upper electrode module 11 is confirmed. The position or inclination of the upper electrode module 11 is detected by various methods, and thus the present invention is not limited thereto.

[0027] FIG. 4 illustrates an embodiment of a side wall structure in the adjustment system according to the present invention.

[0028] Referring to FIG. 4, it includes a shower head 111 disposed below the upper electrode module 11, and the shower head 111 includes an inclination guiding portion 111a inclined outward. The upper electrode module 11 and the shower head 111 may be generally disk-shaped as a whole. The gas in the upper portion of the upper electrode module 11 needs to be purged along the gap formed on the peripheral surface of the upper electrode module 11. While the gas is quickly discharged, the edge of the shower head 111 can be inclined from the upper side to the lower side so as not to affect the process space, and thus the inclination guiding portion 111a can be formed at the edge of the shower head 111. Then, an inclination guiding gap (GP) can be formed along the periphery of the frame block 121 and the shower head 111 by such an inclination guiding portion 111a. And, while the gas is quickly discharged by such an inclination guiding gap (GP), it does not affect the process space. The inclination guiding gap (GP) can have various extension lengths, and thus the present invention is not limited thereto.

[0029] FIG. 5 illustrates an embodiment of a gas purge structure in the adjustment system according to the present invention.

[0030] Referring to FIG. 5, it further includes a purge gap formed on the peripheral surface of the upper electrode module 11. The process gas flowing in along the central induction hole 22 flows along the induction pipeline 15a and enters the chamber through the shower head 111. Also, the purge gas is injected along the purge hole (PH) formed in the lead 12, flows between the upper electrode module 11 and the lead 12, and can flow along the purge gap (GP) formed between the upper electrode module 11 and the inner surface of the chamber side wall. For example, an inert gas with low reactivity such as nitrogen or argon can be injected through the central induction hole 22 and flow along the induction pipeline 15a. Thereby, while the gas or plasma inside the vacuum chamber is prevented from flowing upward, the intermediate products generated from the etching process are prevented from depositing on the upper space, preventing the generation of particles. For this purpose, the edge of the shower head can be formed to be inclined as described above. Or, as will be described later, a ground ring is arranged on the peripheral surface of the shower head.

[0031] FIG. 6 illustrates an embodiment of the electrode grounding structure in the adjustment system according to the present invention.

[0032] Referring to FIG. 6, it further includes a ground ring 61 coupled to the peripheral surface of the upper electrode module 11. The ground ring 61 includes a circular ring base 611 and a plurality of flow holes 612_1 to 612_N formed along the ring base 611. An inclined guiding portion 111a is formed at the edge portion of the shower head 111, and a ground ring 61 is disposed around the upper surface of the shower head 111. The ground ring 61 is circular ring-shaped and may consist of a circular ring base 611 and a plurality of flow holes 612_1 to 612_N formed along the ring base 611. The ring base 611 is ring-shaped with a square cross-section, and a plurality of flow holes 612_1 to 612_N through which gas can flow may be formed along the inner surface of the ring base 611. The ground ring 61 is disposed to be located in a purge gap formed between the edge of the shower head 111 and the inner surface of the chamber sidewall. The gas (G) flowing in along the central guiding hole 22 flows along the guiding pipeline 15a and into the chamber through the shower head 111. Also, the purge gas (PG) flows into the upper side of the upper electrode module 11 through the purge hole (PH). Thereafter, the purge gas (PG) can flow along the purge gap formed on the peripheral surface of the upper electrode module 11, penetrate through the flow holes 612_1 to 612_N of the ground ring 61, and flow along the inclined guiding portion 111a. The ground ring 61 is made of a material having elasticity or elasticity, whereby its size is adjusted according to the coupling position with respect to the upper electrode module 11. The ground ring 61 has various structures, whereby the present invention is not limited thereby.

[0033] As described above, the present invention has been described in detail with reference to the presented embodiments. However, those skilled in the art can make various modifications and variations of the invention without departing from the technical idea of the present invention with reference to the presented embodiments. The present invention is not limited by such modified and variant inventions, but is limited only by the scope of the claims.

Description of Reference Numerals

[0034] 11: Upper electrode module 12: Lead 13: Lower electrode module 14a, 14b: Motor 15a, 15b: Induction pipeline 22: Induction hole 61: Grounding ring 111: Shower head 111a: Inclination induction part 612_1 to 612_N: Flow hole

Claims

1. An upper electrode module 11 disposed opposite to a lower electrode module 13 in a process chamber (C), A lead 12 coupled to an upper portion of the process chamber (C), At least three motors 14a, 14b disposed on an upper surface of the lead 12, Connecting means for connecting at least three motors 14a, 14b and the upper electrode module 11, An upper electrode tilt and position adjustment system, characterized in that.

2. The tilt or position of the upper electrode modules 14a, 14b is adjusted by the operation of the connecting means by at least three motors 14a, 14b The upper electrode tilt and position adjustment system according to claim 1.

3. The connecting means is connected to the upper electrode module 11 through bellows-structured induction pipelines 15a, 15b The upper electrode tilt and position adjustment system according to claim 1.

4. At least three motors 14a, 14b are arranged separately from each other at an edge of the lead 12 The upper electrode tilt and position adjustment system according to claim 1.

5. At least three motors 14a, 14b are arranged separately from each other at a central portion of the lead 12 The upper electrode tilt and position adjustment system according to claim 1.

6. At least three motors 14a, 14b are connected to the upper electrode module 11 by connecting means through one induction hole 22 The upper electrode tilt and position adjustment system according to claim 5.

7. Including a shower head 111 disposed below the upper electrode module 11, the shower head 111 includes an inclined induction portion 111a inclined outward The tilt and position adjustment system of the upper electrode according to claim 1.

8. Further comprising a purge gap formed on the peripheral surface of the upper electrode module 11 The tilt and position adjustment system of the upper electrode according to claim 1.

9. Further comprising a ground ring 61 coupled to the peripheral surface of the upper electrode module 11, the ground ring 61 including a circular ring base 611 and a plurality of flow holes 612_1 to 612_N formed along the ring base 611 The tilt and position adjustment system of the upper electrode according to claim 1.

10. The ground ring 61 has elasticity The tilt and position adjustment system of the upper electrode according to claim 9.

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