Wafer unclamping device and method

Abstract

The invention discloses a wafer unchucking device and a wafer unchucking method which can be used in a semiconductor process. Here, the wafer unchucking apparatus may include: a chuck (Chuck) on which a wafer is placed; the first wafer ring is positioned above the wafer; the second wafer ring is used for placing the wafer; and a shaft which is driven by a drive unit so as to move the first wafer ring and the second wafer ring in the upward direction in sequence. In addition, the wafer unchucking method may include: a step of moving the first wafer ring by a ring shaft; and a step in which the ring shaft moves a second wafer ring on which the wafer is placed and separates the wafer from the chuck.

Description

Technical Field

[0001] The present invention relates to a device and method for unclamping a wafer, and more particularly to a device and method for moving a wafer fixed in a chamber of a semiconductor manufacturing process equipment out of the equipment without being damaged. Background Art

[0002] In the semiconductor manufacturing process system, in the evaporation process or etching process using plasma, it is necessary to fix the loaded wafer to the equipment inside the chamber of the semiconductor manufacturing equipment. In the industry, a mechanical chuck (Mechanical-Chuck, M-Chuck) that physically presses the wafer can be used, or an electrostatic chuck (Electrostatic Force Chuck, ESC) that fixes the wafer to the chuck (Chuck) by electrostatic force can be used.

[0003] When such a deposition process or etching process is completed, a de-chucking operation is performed to safely separate the wafer from the chuck as a preparatory operation for unloading the wafer inside the equipment for the following process. However, in the case of lift pins that lift the wafer for unloading in conventional semiconductor equipment, the wafer may not be separated from the chuck, and further, the wafer may be damaged or the quality may be reduced for the following reasons.

[0004] First, in the process using a mechanical chuck (M-Chuck), in the case of a clamp (clamp) made of a rubber material O-ring to fix the wafer, the wafer may not be separated from the chuck normally due to the adhesive force between the wafer and the mechanical chuck (M-Chuck) due to the nature of the material. In addition, in the case of an electrostatic chuck (ESC), the wafer may not be separated from the chuck normally due to the electromagnetic force between the wafer and the electrostatic chuck (ESC) when the charge of the wafer electrode cannot be released or the wafer is too thin, or when various types of gases are injected into the chamber and the electromagnetic force is maintained by the chemical reaction of the gas or the inherent characteristics of the gas.

[0005] As a result, there may be a problem in the process such as the wafer being separated while being deviated from the central axis due to the attraction generated between the wafer and the chuck, or further, the wafer may be broken instead of falling horizontally from the chuck.

[0006] In the past, the de-chucking problem was solved by moving the focus ring up and down in a drive device located below the chamber to physically separate the wafer and the chuck, and providing a tube that can limit the moving range of the focus ring. However, in the case of a device in which a part such as a shadow ring that is used to block the periphery of the wafer to produce a shadow is arranged above the wafer, the de-chucking system that utilizes the existing moving range limiting auxiliary materials cannot be used as usual.

[0007] Patent Document 1: KR10-2020-0170315B1 Summary of the invention

[0008] The object of the present invention is to provide a method and device for safely de-chucking by utilizing a drive system of the part when, in a semiconductor process, a device having a special part such as a shadow ring disposed above a chuck performs a chucking operation in advance and when, before a single process is completed and the wafer is unloaded from the device, it is difficult to easily separate the wafer from the chuck due to the gravitational force generated between the chuck and the wafer.

[0009] It can be that a wafer de-clamping device according to an embodiment of the present invention for achieving the above-mentioned purpose includes: a chuck, on which the wafer is placed; a first wafer ring, which is located above the wafer; a second wafer ring, on which the wafer is placed; and a shaft, which is driven by a driving unit, so that the first wafer ring and the second wafer ring are moved upward in sequence.

[0010] It may be that, in a wafer de-chucking device according to an embodiment of the present invention, the chuck includes a mechanical chuck (Mechanical chuck, M-chuck) or an electrostatic chuck (Electrostatic chuck, ESC), and the first wafer ring includes a clamp ring (clamp ring) or a shadow ring (shadow ring).

[0011] It may be that, in a wafer de-chucking device according to an embodiment of the present invention, a plurality of first wafer rings are provided in the device.

[0012] It may be that, in the wafer de-chucking device according to an embodiment of the present invention, the second wafer ring includes a focus ring.

[0013] Alternatively, in a wafer dechucking device according to an embodiment of the present invention, the ring shaft may be composed of an upper shaft portion, a central shaft portion, and a lower shaft portion having different diameters to form a multi-stage structure.

[0014] It may be that, in the wafer de-chucking device according to an embodiment of the present invention, the diameter of the upper shaft portion is smaller than the diameter of the central shaft portion, and the diameter of the central shaft portion is smaller than the diameter of the lower shaft portion.

[0015] Alternatively, in the wafer dechucking device according to an embodiment of the present invention, a first through hole for allowing the upper shaft portion to pass therethrough is formed in the first wafer ring.

[0016] It may be that, in the wafer de-chucking device according to an embodiment of the present invention, the diameter of the first through hole is larger than the diameter of the upper shaft portion and smaller than the diameter of the central shaft portion.

[0017] In the wafer dechucking device according to an embodiment of the present invention, a second through hole for passing the central axis portion may be formed in the second wafer ring.

[0018] It may be that, in the wafer de-chucking device according to an embodiment of the present invention, the diameter of the second through hole is larger than the diameter of the central shaft portion and smaller than the diameter of the lower shaft portion.

[0019] It may be that, in a wafer de-clamping device according to an embodiment of the present invention, the first wafer ring is placed on a first placing portion of the ring shaft located at a boundary between the upper shaft portion and the central shaft portion, and the second wafer ring is placed on a second placing portion of the ring shaft located at a boundary between the central shaft portion and the lower shaft portion.

[0020] Alternatively, in a wafer de-chucking device according to an embodiment of the present invention, a placement groove engaging with the second placement portion is formed on a bottom surface of the second wafer ring.

[0021] It may be that, in a wafer de-clamping device according to an embodiment of the present invention, the length of the central axis portion is greater than or equal to the distance that the first wafer ring can move plus the thickness of the second wafer ring, and the lower axis portion is formed to be greater than or equal to the distance that the second wafer ring can move.

[0022] It may be that, in a wafer de-chucking device according to an embodiment of the present invention, in the axial direction of the ring axis, a distance that the first wafer ring can move is formed to be larger than a distance that the second wafer ring can move.

[0023] A wafer de-chucking method according to an embodiment of the present invention may include: a step of moving a first wafer ring by a shaft; and a step of moving a second wafer ring on which a wafer is placed by the shaft to separate the wafer from a chuck.

[0024] It may be that in a wafer de-chucking method according to an embodiment of the present invention, the ring shaft is formed of a multi-stage structure of an upper shaft portion, a central shaft portion, and a lower shaft portion with different diameters so that the first wafer ring and the second wafer ring can move sequentially.

[0025] It may be that, in a wafer de-clamping method according to an embodiment of the present invention, the length of the central axis portion is greater than or equal to the distance that the first wafer ring can move plus the thickness of the second wafer ring, and the lower axis portion is greater than or equal to the distance that the second wafer ring can move.

[0026] It may be that, in a wafer de-chucking method according to an embodiment of the present invention, the wafer de-chucking method further comprises a step of lifting the wafer between the first wafer ring and the second wafer ring toward the axial direction of the ring axis by lifting pins.

[0027] According to an embodiment of the present invention, when the wafer is separated from the chuck, a special part such as a shadow ring located above the wafer is first lifted, but a device driven in the lifting operation or a de-chucking operation can be performed in a linked manner. As a result, there is no need to add a separate device for moving the first wafer ring including the clamp ring or the shadow ring, and multiple lifting can be performed with one ring shaft, and further, damage to the wafer or reduction in production quality can be prevented.

[0028] In more detail, the second wafer ring may be moved using the driving device for moving the first wafer ring, and further, the wafer may be prevented from being damaged in advance while the wafer lifting operation immediately following the wafer unclamping is stably performed.

[0029] The effects according to the present invention are not limited to those exemplified above, and more various effects are included in the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 2 is a diagram showing a first wafer ring, a second wafer ring, and a ring shaft of a wafer de-chucking device according to an embodiment of the present invention.

[0031] Figure 2 (a) is a diagram showing a wafer fixed on a mechanical chuck (M-Chuck).

[0032] Figure 2 (b) is a diagram showing a wafer fixed on an electrostatic chuck.

[0033] Figure 3 FIG. 1 is a diagram showing a wafer de-chucking device according to an embodiment of the present invention.

[0034] Figure 4FIG. 1 is a diagram showing a ring shaft of a wafer de-chucking device according to an embodiment of the present invention.

[0035] Figure 5 FIG. 1 is a diagram showing a through hole of a wafer de-chucking device according to an embodiment of the present invention.

[0036] Figure 6 FIG. 1 is a diagram showing a placement slot of a wafer de-chucking device according to an embodiment of the present invention.

[0037] Figure 7 FIG. 1 is a diagram showing a driving unit of a wafer de-chucking device according to an embodiment of the present invention.

[0038] Figure 8 is a flow chart illustrating a wafer de-chucking method according to an embodiment of the present invention.

[0039] (Explanation of Reference Numerals)

[0040] 100: Wafer de-clamping device 102: Chuck

[0041] 110: first wafer ring 120: second wafer ring

[0042] 130: Ring shaft 132: Upper shaft

[0043] 134: Central axis 136: Lower axis

[0044] 140: first placement portion 142: second placement portion

[0045] 144: mounting groove 150: first through hole

[0046] 152: second through hole 154: third through hole

[0047] 160: Lifting pin 200: Driving unit

[0048] 202: Driver 204: Driving rod

[0049] 206: Driving Platform DETAILED DESCRIPTION

[0050] The purpose, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments associated with the attached drawings. In this case, the same components may be represented by the same symbols in each of the drawings. In addition, the detailed description of the already known functions and / or structures will be omitted.

[0051] In the following disclosure, the parts necessary for understanding the operation according to various embodiments are mainly described, and the description of factors that may obscure the gist of the description is omitted. In addition, some of the components of the drawings may be exaggerated, omitted, or schematically shown. The size of each component does not fully reflect the actual size, and therefore, the content described herein is not limited by the relative size or spacing of the components depicted in each drawing.

[0052] When describing the embodiments of the present invention, if it is judged that the specific description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description is omitted. In addition, the terms described below are defined as terms considering the functions in the present invention, which may be different according to the intentions or conventions of the user or operator. Therefore, its definition should be made based on the overall content of this specification. The terms used in the detailed description are only used to describe the embodiments of the present invention and are by no means limited. Unless clearly used separately, the expression in the singular includes the meaning of the plural form. In this description, expressions such as "including" or "having" are used for any characteristic, number, step, work, element, part or combination of these, and should not be interpreted as excluding the existence or possibility of one or more different characteristics, numbers, steps, work, components, part or combination of these, except for the case of description.

[0053] In addition, the terms "first", "second", etc. may be used to describe various constituent elements, but the constituent elements are not limited by the terms. The terms are only used to distinguish one constituent element from other constituent elements.

[0054] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0055] Figure 1 FIG. 4 is a structural diagram showing a wafer de-chucking device 100 according to an embodiment of the present invention.

[0056] Reference Figure 1 The wafer de-chucking device 100 may be constructed to include: a chuck 102 for placing the wafer; a first wafer ring 110 located above the wafer; a second wafer ring 120 for placing the wafer; and a shaft 130, which is driven by a driving unit to move the first wafer ring 110 and the second wafer ring 120 upward in sequence.

[0057] <Chuck>

[0058] The chuck 102 is a device that performs functions such as chucking to fix the wafer in the chamber of the plasma processing device and de-chucking to separate the wafer. It can be implemented in various ways such as a mechanical chuck (M-Chuck) that fixes the wafer by physical force and an electrostatic chuck (ESC) that fixes the wafer by electrostatic force. Through it, the evaporation and etching process can be stably performed on the wafer.

[0059] In more detail, Figure 2 As shown in (a), the mechanical chuck (M-Chuck) can mechanically support the outer portion of the wafer using a clamp ring or the like.

[0060] At this time, when the clamp for fixing the wafer in the mechanical chuck (M-Chuck) is formed of a rubber material, an adhesive force (Sticking) may be generated between the wafer and the mechanical chuck (M-Chuck) due to the properties of the material.

[0061] In addition, if Figure 2 As shown in (b), the electrostatic chuck ESC applies voltage to the lower electrode to generate an electrostatic force between the chuck 102 and the wafer, thereby fixing the wafer on the chuck 102.

[0062] At this time, when the electrostatic chuck is performing the un-chucking operation of the semiconductor device chuck 102 to separate the wafer from the chuck 102 , even if the process is completed and the wafer is un-chucking, a micro charge remains between the chuck 102 and the wafer, and an Un De-Chuck (Discharge) phenomenon may occur.

[0063] In addition, in the present invention, if Figure 5 As shown, a third through hole 154 is formed in the chuck 102 to provide a path for driving the ring shaft 130 described later.

[0064] <First Wafer Ring>

[0065] Reference Figure 3 The wafer de-chucking device 100 may include a first wafer ring 110 located above the wafer in a shape surrounding an outer circumferential surface of the wafer.

[0066] At this time, the first wafer ring 110 may be configured to include at least one of a clamp ring or a shadow ring.

[0067] In addition, Figure 3The example in FIG. 1 illustrates a case where the first wafer ring 110 is provided in a singular number, but the present invention is not limited thereto, and the first wafer ring 110 may also be provided in a plurality in the device.

[0068] In addition, as in Figure 3 As can be seen in FIG. 1 , the first wafer ring 110 may be formed in a ring configuration.

[0069] In more detail, while the clamp ring or shadow ring is located above the chuck 102 and the second wafer ring 120, it can stably support or fix the wafer in a single process using plasma and can perform functions such as protecting the outer peripheral surface of the wafer.

[0070] First through hole

[0071] like Figure 5 As shown, a first through hole 150 through which an upper shaft portion 132 to be described later passes may be formed in the first wafer ring 110 .

[0072] The first through holes 150 may be formed with the same number of holes as the number of the ring shafts 130 disposed in the device.

[0073] The diameter of the first through hole 150 may be larger than the diameter of the upper shaft portion 132 and smaller than the diameter of the central shaft portion 134 .

[0074] Thus, the first through hole 150 can penetrate the upper shaft portion 132 and be fixed by the upper shaft portion 132 , and be placed above the central shaft portion 134 .

[0075] <Shaft>

[0076] Reference Figure 3 The wafer de-chucking device 100 may include a shaft 130 that transmits power generated in the driving unit 200 to the first wafer ring 110 and the second wafer ring 120 when a process such as thin film evaporation or etching is completed.

[0077] At this time, the ring shaft 130 may be provided in plurality in the device.

[0078] like Figure 4 As shown, the ring shaft 130 may form a multi-stage structure including an upper shaft portion 132 , a central shaft portion 134 , and a lower shaft portion 136 .

[0079] like Figure 4 As shown, the annular shaft 130 may form a first receiving portion 140 at a boundary between the upper shaft portion 132 and the central shaft portion 134 , and a second receiving portion 142 at a boundary between the central shaft portion 134 and the lower shaft portion 136 .

[0080] The upper shaft portion 132 may be formed in a structure in which a diameter gradually decreases toward the upper side in a part or in the entire region.

[0081] The diameter of the upper shaft portion 132 may be smaller than the diameter of the first through hole 150 .

[0082] In more detail, the upper shaft portion 132 may penetrate through and engage with the first through hole 150 of the first wafer ring 110 while being connected to the first wafer ring 110 .

[0083] The upper shaft portion 132 may penetrate and drive the first through hole 150 of the first wafer ring 110 while fixing the first wafer ring 110 .

[0084] In more detail, when the ring shaft 130 rises, the upper shaft portion 132 passes through the first through hole 150 of the first wafer ring 110 , and the first wafer ring 110 can be placed on the first placement portion 140 of the ring shaft 130 .

[0085] Due to the lifting action of the ring shaft 130 , the first through hole 150 of the first wafer ring 110 is in a state of being engaged with the first receiving portion 140 of the ring shaft 130 , and the first wafer ring 110 can be separated from the wafer.

[0086] Furthermore, the length of the central axis portion 134 of the ring axis 130 may be greater than or equal to the distance that the first wafer ring 110 can move plus the thickness of the second wafer ring 120 , and the lower axis portion 136 may be formed to be greater than or equal to the distance that the second wafer ring 120 can move.

[0087] Reference Figure 3 In the first wafer ring 110 , the second wafer ring 120 and the chuck 102 , a number of holes for the ring shaft 130 to pass through may be formed that is equivalent to the number of the ring shaft 130 .

[0088] In more detail, Figure 5 As shown, a first through hole 150 for the ring shaft 130 to pass through may be formed in the first wafer ring 110 .

[0089] In addition, if Figure 5 As shown, a second through hole 152 for the ring shaft 130 to pass through may be formed in the second wafer ring 120 .

[0090] In addition, if Figure 5 As shown, a third through hole 154 for the ring shaft 130 to pass through may be formed in the chuck 102 .

[0091] At this time, refer to Figure 3 as well as Figure 7The ring shaft 130 can be driven by the driving force received by the driving unit 200.

[0092] In addition, as an embodiment of the present invention, a control module for controlling the driving of the ring shaft 130 may be provided, and further, one or more sensors that can provide data for controlling the driving of the ring shaft 130 may be provided.

[0093] In more detail, the control module may control the driving of the ring shaft 130 based on the driving position of the ring shaft 130 provided from a position sensor.

[0094] Furthermore, in the control module, the section for driving the ring shaft 130 can be divided into a plurality of sub-sections, so that the driving speed and the like for each sub-section can be controlled differently from each other.

[0095] For a more detailed example, in the control module, for a first interval including the time point when the ring shaft 130 is placed on the second wafer ring 120, the second wafer ring 120 can be safely placed on the ring shaft 130 while the driving speed is reduced.

[0096] On the contrary, in the control module, the driving speed in the sections before and after the first section may be made faster than the driving speed in the first section, thereby shortening the overall time required for driving the ring shaft 130 .

[0097] Furthermore, in the control module, at the time point when the ring shaft 130 is placed on the second wafer ring 120 or at the time point when it is pre-driven to a distance equivalent to the reference distance after placement, the driving of the ring shaft 130 can also be controlled to stop at a preset reference time or further reduce the driving speed, thereby reducing the gravitational force between the wafer and the chuck.

[0098] <Second Wafer Ring>

[0099] like Figure 3 As shown, the wafer de-chucking device 100 may include a second wafer ring 120 around which the wafer is placed.

[0100] At this time, the second wafer ring 120 may be configured to include a focus ring.

[0101] Here, the focus ring can maintain uniform density of plasma while fixing the wafer inside the chamber, and can also prevent contamination near the peripheral edge of the wafer.

[0102] In addition, refer to Figure 7In addition to the inherent functions of the second wafer ring 120, the driving force generated in the driving unit 200 is transmitted to the second wafer ring 120 through the ring shaft 130 to realize the up and down movement of the wafer, thereby additionally performing a de-chucking function.

[0103] In more detail, the second wafer ring 120 may be disposed on a portion of the upper region of the chuck 102 and may be disposed below the wafer, and may be manufactured into a shape corresponding to the wafer so as to support the edge of the wafer.

[0104] The second wafer ring 120 may be formed with the same number of second through holes 152 as the number of the ring shafts 130 so that the ring shafts 130 can pass through.

[0105] The ring shaft 130 may be driven while the central shaft portion 134 penetrates the second through hole 152 while the first wafer ring 110 is mounted on the first mounting portion 140 and ascends.

[0106] Specifically, when the ring shaft 130 rises, the central axis portion 134 passes through the second through hole 152 of the second wafer ring 120 , and the second wafer ring 120 can be placed on the second placement portion 142 .

[0107] Reference Figure 6 Due to the subsequent rising action of the ring shaft 130 , the receiving groove 144 at the bottom surface of the second through hole 152 of the second wafer ring 120 is engaged with the second receiving portion 142 of the ring shaft 130 , and the second wafer ring 120 can be separated from the chuck 102 .

[0108] At this time, the placement groove 144 can be implemented as The shape of a letter, a hat, etc., and can be further realized in various shapes such as a shape inclined at a predetermined angle.

[0109] The distance that the first wafer ring 110 can move in the axial direction of the ring shaft 130 can be formed to be greater than the distance that the second wafer ring 120 can move.

[0110] Second through hole

[0111] like Figure 5 As shown, a second through hole 152 for allowing the ring axis 130 to pass through may be formed in the second wafer ring 120 .

[0112] like Figure 6 As shown, a receiving groove 144 penetrated by the central shaft portion 134 and engaged with the second receiving portion 142 may be formed below the second through hole 152 .

[0113] At this time, the diameter of the second through hole 152 may be larger than the diameter of the central shaft portion 134 and smaller than the diameter of the lower shaft portion 136 .

[0114] <Lifting Pin>

[0115] Reference Figure 8 The wafer dechucking device 100 may include a plurality of lifting pins 160 for supporting the inner side of the wafer to lift the wafer upward for the purpose of ensuring a space accessible to a robot arm that unloads the wafer from the process equipment.

[0116] <Driver>

[0117] like Figure 3 and Figure 7 As shown, the driving unit 200 is a device that provides a driving force for the up and down movement of the first wafer ring 110 , and can be composed of a driver 202 , a driving rod 204 , and a driving platform 206 .

[0118] Reference Figure 8 The driving force can be used to move the first wafer ring 110 upward and separate the second wafer ring 120 from the chuck 102 upward.

[0119] Drive

[0120] The driver 202 may be combined with the base to provide a driving force for the first wafer ring 110 and the second wafer ring 120 to move up and down.

[0121] The actuator 202 may be formed by a pneumatic cylinder.

[0122] The driver 202 may be directly connected to the driving platform 206 to transmit driving force.

[0123] Drive platform

[0124] The driving platform 206 is located between the driver 202 and the driving rod 204 and can evenly provide driving force for the second wafer ring 120 to move up and down.

[0125] Drive rod

[0126] The driving rod 204 may be located between the driver 202 and the second wafer ring 120 and transmit the driving force of the driver 202 to the first wafer ring 110 to the second wafer ring 120 .

[0127] The driving rods 204 may be configured in plurality and arranged at a certain interval around the second wafer ring 120 , so as to be used to stably maintain the horizontal alignment of the second wafer ring 120 during the up and down movement.

[0128] A third through hole 154 for the lower shaft portion 136 to move may be formed in the chuck 102 .

[0129] The third through hole 154 in the chuck 102 may be provided with an airtight member to maintain the vacuum state of the chamber.

[0130] Next, a wafer de-chucking method according to another embodiment of the present invention is described.

[0131] Reference Figure 8 According to an embodiment of the present invention, a wafer de-chucking method (S300) may include: a step of moving a first wafer ring 110 by a shaft 130 (S302); and a step of moving a second wafer ring 120 on which a wafer is placed to separate the wafer from a chuck 102 (S304).

[0132] The structure and function of the chuck 102, first wafer ring 110, second wafer ring 120, ring shaft 130, lifting pin 160, drive unit 200, and driver 202 used in such a wafer unloading method have been described through the aforementioned embodiments, so the following description will focus on the wafer de-chucking method using these components.

[0133] <First Wafer Ring Moving Step>

[0134] First, refer to Figure 8 , the ring shaft 130 may perform the step of moving the first wafer ring 110 by the driving force received from the driving part 200 ( S302 ).

[0135] Specifically, when the ring shaft 130 rises, the upper shaft portion 132 passes through the first through hole 150 of the first wafer ring 110 , and the first wafer ring 110 can be placed on the first placement portion 140 .

[0136] Then, due to the upward movement of the ring shaft 130 , the first through hole 150 of the first wafer ring 110 is in a state of being engaged with the first receiving portion 140 of the ring shaft 130 , and the first wafer ring 110 can be separated from the wafer.

[0137] As an embodiment of the present invention, as the driving rod 204 of the driving unit rises, the ring shaft 130 can move the first wafer ring 110 such as a shadow ring or a clamp ring at a certain interval (d1).

[0138] At this time, the length of the central axis portion 134 may be greater than or equal to the distance that the first wafer ring 110 can move plus the thickness of the second wafer ring 120 .

[0139] <Second Wafer Ring Moving Step: Unclamping>

[0140] Reference Figure 8The ring shaft 130 moves the second wafer ring 120 on which the wafer is placed so as to perform a step (S304) of separating the wafer from the chuck 102.

[0141] The second wafer ring 120 moving step ( S304 ) pushes the outer portion along the periphery of the wafer so that it can be separated from the chuck 102 .

[0142] After the first wafer ring 110 moving step ( S302 ), the second wafer ring 120 moving step ( S304 ) may be sequentially performed.

[0143] Specifically, when the ring shaft 130 rises, the central axis portion 134 passes through the second through hole 152 of the second wafer ring 120 , and the second wafer ring 120 can be placed on the second placement portion 142 of the ring shaft 130 .

[0144] With the first wafer ring 110 fixed to the first mounting portion 140 , the ring shaft 130 is raised so that the central shaft portion 134 can pass through the second through hole 152 .

[0145] Furthermore, due to the subsequent lifting effect of the ring shaft 130 , the second through hole 152 of the second wafer ring 120 is in a state of being engaged with the second receiving portion 142 , and the second wafer ring 120 can be separated from the chuck 102 .

[0146] Reference Figure 4 The ring shaft 130 is formed of a multi-stage structure of an upper shaft portion 132, a central shaft portion 134, and a lower shaft portion 136 having different diameters, so that the first wafer ring 110 and the second wafer ring 120 can move sequentially.

[0147] The ring shaft 130 can push the second wafer ring 120 to a preset certain height (d2) to implement unclamping.

[0148] In more detail, the length of the lower shaft portion 136 may be greater than or equal to a distance that the second wafer ring 120 may move.

[0149] As an embodiment of the present invention, in the second wafer ring 120 moving step (S304), when a mechanical chuck (M-Chuck) is used in a single process, the wafer attached to the chuck can be separated due to the O-ring made of rubber material, and when an electrostatic chuck ESC is used in a single process, the wafer attached to the chuck can be separated due to electrostatic force.

[0150] When using an electrostatic chuck ESC, the second wafer ring 120 moving step (S304) separates the wafer from the influence of the electrostatic force of the electrostatic chuck before the wafer is raised by the lifting pins 160, and can separate it by a minimum distance equivalent to the degree of deviation from the influence of residual static electricity that is not discharged.

[0151] <Lifting pin movement steps>

[0152] Reference Figure 8 In order to unload the substrate from the single process equipment, a step of moving the lift pins 160 to move the wafer separated from the electrostatic chuck to the upper side of the electrostatic chuck may be included (S306).

[0153] The lifting pin 160 moving step ( S306 ) can lift the wafer within a range not exceeding the spacing between the first wafer ring 110 and the wafer after the first wafer ring 110 moving step ( S302 ) and the second wafer ring 120 moving step ( S304 ) are completed.

[0154] The step of moving the lift pins 160 ( S306 ) may further include a step of unloading the wafer moved upward to the outside of the chamber.

[0155] In the case of the present embodiment, as a case where the wafer is separated from the chuck 102 after the first wafer ring 110 and the second wafer ring 120 are separated in sequence, after the wafer is separated from the chuck 102 once through the second wafer ring moving step (S304), it is separated a second time through the lifting pin 160 moving step (S306), so that the wafer can be stably moved out without being out of the position of the wafer which may occur in the existing single process.

[0156] That is, it is possible to prevent in advance the possibility that when the wafer is lifted upward, the position of the wafer is shifted from the center due to the attraction between the wafer and the chuck 102, thereby reducing the quality or physically damaging the substrate.

[0157] If the driving platform 206 rises through the driver 202, the driving rod 204 and the ring shaft 130 can be raised. Through such driving force, the ring shaft 130 first lifts the first wafer ring 110 such as the shadow ring or the clamp ring to a predetermined certain height (d1). Then, while lifting the second wafer ring 120 such as the focus ring to a predetermined certain height (d2), the second wafer ring 120 such as the focus ring is utilized to release the clamped wafer.

[0158] Next, for unloading the substrate, the lifting unit can be used to move the unclamped wafer to the upper side of the chuck 102. The inner side of the wafer can be lifted by the lifting pins 160 of the lifting unit, but it can be set to rise by a length corresponding to the thickness (t) of the robot arm within a range not exceeding the separation distance between the first wafer ring 110 such as a shadow ring or a clamp ring and the second wafer ring 120 such as a focus ring.

[0159] An embodiment of the present invention has been described above. A person having ordinary knowledge in the technical field can make various modifications and changes to the present invention by adding, changing, deleting or appending constituent elements without departing from the scope of the concept of the present invention as described in the claims, which are also included in the scope of rights of the present invention.

Claims

1. A wafer de-clamping device, comprising: Chuck, for placing wafers; A first wafer ring, located above the wafer; A second wafer ring for placing the wafer; as well as The ring shaft is driven by a driving unit, so that the first wafer ring and the second wafer ring are moved upward in sequence.

2. The wafer de-chucking device according to claim 1, wherein: The chuck includes a mechanical chuck or an electrostatic chuck, and the first wafer ring includes a clamp ring or a shadow ring.

3. The wafer de-chucking device according to claim 1, wherein: The first wafer ring is provided in plurality.

4. The wafer de-chucking device according to claim 1, wherein: The second wafer ring includes a focus ring.

5. The wafer de-chucking device according to claim 1, characterized in that: The annular shaft is composed of an upper shaft portion, a central shaft portion, and a lower shaft portion having different diameters from each other to form a multi-stage structure.

6. The wafer de-chucking device according to claim 5, characterized in that: The diameter of the upper shaft portion is smaller than the diameter of the central shaft portion, and the diameter of the central shaft portion is smaller than the diameter of the lower shaft portion.

7. The wafer de-chucking device according to claim 5, characterized in that: A first through hole is formed in the first wafer ring so that the upper shaft portion passes therethrough. The diameter of the first through hole is larger than the diameter of the upper shaft portion and smaller than the diameter of the central shaft portion.

8. The wafer de-chucking device according to claim 5, characterized in that: A second through hole is formed in the second wafer ring so that the central axis portion passes therethrough. The diameter of the second through hole is larger than the diameter of the central shaft portion and smaller than the diameter of the lower shaft portion.

9. The wafer de-chucking device according to claim 5, characterized in that: The first wafer ring is placed on a first placement portion of the ring shaft located at the boundary between the upper shaft portion and the central shaft portion. The second wafer ring is placed on a second placement portion of the ring shaft located at a boundary between the central shaft portion and the lower shaft portion.

10. The wafer de-chucking device according to claim 9, characterized in that: A receiving groove engaged with the second receiving portion is formed on the bottom surface of the second wafer ring.

11. The wafer de-chucking device according to claim 5, characterized in that: The length of the central shaft portion is greater than or equal to the distance that the first wafer ring can move plus the thickness of the second wafer ring, and the length of the lower shaft portion is greater than or equal to the distance that the second wafer ring can move.

12. The wafer de-chucking device according to claim 1, characterized in that: In the axial direction of the ring axis, the first wafer ring can move a distance greater than the second wafer ring can move a distance.

13. A wafer de-chucking method, comprising: The ring shaft moves the first wafer ring; as well as The ring shaft moves the second wafer ring on which the wafer is placed to separate the wafer from the chuck.

14. The wafer de-chucking method according to claim 13, characterized in that: The ring shaft is formed of a multi-stage structure of an upper shaft portion, a central shaft portion, and a lower shaft portion having different diameters from each other so that the first wafer ring and the second wafer ring can be moved sequentially.

15. The wafer de-chucking method according to claim 14, characterized in that: The length of the central shaft portion is greater than or equal to the distance that the first wafer ring can move plus the thickness of the second wafer ring, and the length of the lower shaft portion is greater than or equal to the distance that the second wafer ring can move.

16. The wafer de-chucking method according to claim 13, characterized in that: The wafer de-chucking method further comprises: The step of using lift pins to lift the wafer between the first wafer ring and the second wafer ring in the axial direction of the ring axis.

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