Patent Application
20190214283
The present inventive concept relates to a process system of performing a fabrication process and a torque initiated lifting tool included therein.
Multi-chamber process systems are widely used in a fabrication of semiconductor devices. With multi-chamber process systems, various processes are performed in the multi-chamber process systems. Multi-chamber process systems include a transfer chamber to facilitate a distribution of a wafer among at least two or more process chambers. To conduct maintenance of the multi-chamber process systems, a lid of the transfer chamber is lifted. Such lifting may be performed by using a robotic arm including gas springs and pneumatic actuators or by using a pry bar. With the robotic arm, the multi-chamber systems are expensive and need extra maintenance for the mechanism of the robotic arm. In the case where the pry bar is used, applying leverage to the handle may cause damage the lid of the transfer chamber or a surface of the multi-chamber process systems on which the pry bar touches.
According to an exemplary embodiment of the present inventive concept, a process system of performing a fabrication process on a wafer includes a wafer storage cassette, process chambers, a transfer chamber having a body and a lid that detachably covers the body, a frame configured to support the transfer chamber, and a lifting tool connected to the lid and extended from the lid over a portion of the frame. The body of the transfer chamber is connected to the wafer storage cassette and the plurality of process chambers so that the wafer is transferred from the wafer storage cassette through the body of the transfer chamber to one of the process chambers.
According to an exemplary embodiment of the present inventive concept, a process system of performing a fabrication process on a wafer includes a chamber having a body and a lid that detachably covers the body, a frame configured to support the body of the chamber and a lifting tool connected to the lid and extended from the lid over a portion of the frame. The lifting tool includes a mounting plate connected to an upper surface of the lid, a threaded rod penetrating the mounting plate so that the threaded rod is disposed over the portion of the frame, a knob connected to an upper end of the threaded rod, and a pad connected to a lower end of the threaded rod.
According to an exemplary embodiment of the present inventive concept, a torque initiated lifting tool includes a mounting plate having holes, a threaded rod penetrating one of the holes, at least two fastener rods penetrating the other holes of the holes, a knob connected to an upper end of the threaded rod, and a pad connected to a lower end of the threaded rod. The at least two fasteners rods attach the mounting plate to a lid of a chamber in a process system of performing a fabrication process on a wafer.
These and other features of the present inventive concept will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings of which:
It will be appreciated that for simplicity and clarity of illustration, elements illustrated in the drawings have not necessarily been drawn to scale. For example, the dimensions of some of the elements are exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals have been repeated among the drawings to indicate corresponding or analogous elements.
Exemplary embodiments of the present inventive concept will be described below in detail with reference to the accompanying drawings. However, the inventive concept may be embodied in different forms and should not be construed as limited to the embodiments set forth herein.
In
The wafer storage cassette 110 may be provided in plural. For example, the process system 100 includes two wafer storage cassettes. The wafer storage cassette 110 receives a wafer to be processed in at least one of the process chambers 120 and distributes the wafer to one of the process chambers 120 through the front transfer chamber 130 or the rear transfer chamber 140 according to a process sequence. The process sequence may be controlled using a controller (not shown here).
The front transfer chamber 130 may include a robotic arm (not shown here) to transfer a wafer from the wafer storage cassette 110 to one of the process chambers 120. The robotic arm of the front transfer chamber 130 may also transfer a wafer from one of the process chambers 120 to another process chamber of the process chambers 120. The robotic arm of the front transfer chamber 130 may be controlled by the controller.
The rear transfer chamber 140 may include a robotic arm (not shown here) to transfer a wafer received from the front transfer chamber 130 to one of the process chambers 120. The robotic arm of the rear transfer chamber 140 may also transfer a wafer from one of the process chambers 120 to another one of the process chambers 120. The front transfer chamber 130 is substantially the same in structure and operation with the rear transfer chamber 140, except for their locations in the process system 100.
Each of the front transfer chamber 130 and the rear transfer chamber 140 includes a body TC_B and a lid TC_L. For the convenience of a description, the rear transfer chamber 140 will be described with reference to
The O-ring 180 may be a loop of elastomer with a round cross-section. The O-ring 180 is seated in a groove formed in the body TC_B and the lid TC_L and compressed while the rear transfer chamber 140 is pumped, creating a seal at the interface between the body TC_B and the lid TC_L.
To clean the interior of the body TC_B for maintenance of the process system 100, the lid TC_L is lifted and the interior of the body TC_B is exposed. The lid TC_L detachably covers the body TC_B to maintain the vacuum state while the process system 100, and is lifted for maintenance. A lifting force need to be greater than a threshold static cohesion force between the lid TC_L and the O-ring 180 or between the body TC_B and the O-ring 180. For example, the lid TC_L may be formed of a stainless steel, for example, with a diameter of 40.15 inches. In this case, the O-ring 180 may be compressed by the weight of the lid TC_L that is pulled down by a vacuum force in addition to a gravitational force. The present inventive concept is not limited thereto. For example, the diameter of the lid may be greater or smaller than 40.15 inches.
The lid TC_L has a large surface area which leads to static cohesion of the O-ring 180 with the sealing surfaces of the body TC_B and the lid TC_L. The static cohesion of the O-ring 180 may be formed on the large surface area, and thus the lid TC_L may be difficult to lift only. To lift the lid TC_L, the lifting force may be greater than the threshold static cohesion force.
The frame 150 holds the front transfer chamber 130 and the rear transfer chamber 140. In an exemplary embodiment, the process chambers 120 may be attached to the frame 150. The frame 150 may serve as a structural support of the process system 100.
Referring back to
The first lifting tool 160, as shown in
The second lifting tool 170 is connected to the lid TC_L of the front transfer chamber 130 and extended from the lid TC_L of the front transfer chamber 130 over a portion of the frame 150, like the first lifting tool 160. The first lifting tool 160 and the second lifting tool 170 may be substantially the same in structure except for their locations in the process system 100.
In
The mounting plate 160A is connected to an upper surface of the lid TC_L. The mounting plate 160A is of a triangular shape. The present inventive concept is not limited thereto. For example, the mounting plate 160A may be of a rectangular shape. In this case, two threaded rods may serve to generate a torque force to lift the lid TC_L. Hereinafter, for the convenience of a description, the mounting plate 160A is assumed to be a triangular shape.
The mounting plate 160A has three vertexes near which three holes are formed. One of the three holes receives the threaded rod 160B for applying a downward force to the frame 150, and the other two holes receive two fastener rods for attaching the mounting plate 160A to the lid TC_L of the rear transfer chamber 140.
The first lifting tool 160 further includes a first Teflon layer 160E1 inserted between the mounting plate 160A and the upper surface of the lid TC_L. The first Teflon layer 160E1 may be formed of a Teflon protective material. The first Teflon layer 160E1 may serve to prevent galvanic corrosion from occurring when the mounting plate is in direct contact with the upper surface of the lid TC_L.
The first lifting tool 160 further includes a second Teflon layer 160E2 inserted between the mounting plate 160A and the handle 160F. The second Teflon layer 160E2 may be substantially the same with the first Teflon layer E1 in material.
The threaded rod 160B penetrates the mounting plate 160A so that the threaded rod 160B is disposed over the portion 150P of the frame 150. (See
The knob 160C is connected to an upper end of the threaded rod 160B. The pad 160D is connected to a lower end of the threaded rod 160B.
The pad 160D may be formed of a non-destructive toggle pad. The pad 160D serves as a foot to prevent excessive wear and damage to the upper surface of the frame 150. After the pad 160D lands on, or is in contact with, the portion 150P of the frame 150, turning of the knob 160C may cause the threaded rod 160B to continue to turn so that a downward force continues to be applied to the portion 150P of the frame 150.
Hereinafter, the operation of the first lifting tool 160 will be described with reference to
By rotating the knob 160C in a clockwise, for example, the threaded rod 160B moves down toward the portion 150P of the frame 150 until the pad 160D lands on the portion 150P of the frame 150. To apply a downward force FD to the frame 150, the knob 160C is continuously turned so that the downward force FD is applied to the portion 150P of the frame 150 and in turn generates the torque Tf applied upwardly to the lid TC_L as a reaction force of the downward force FD. The torque FT is determined as follows:
F
T
=−F
D
×L,
where FD represents the downward force and L represents a shortest distance on the mounting plate 160A between the threaded rod 160B and a center of two holes of the mounting plate 160A. The two holes are positioned at an opposite side of the threaded rod 160B.
The first lifting tool 160 further includes a first fastener rod 195A and a second fastener rod 195B penetrating the two holes of the mounting plate 160A. The first fastener rod 195A and the second fastener rod 195B, collectively referred to as a fastener rod 195, may penetrate the two holes of the mounting plate 160A, which are disposed on the lid TC_L, and may partially penetrate into the lid TC_L so that the first lifting tool 160 is attached to the lid TC_L of the rear transfer chamber 140.
In an exemplary embodiment, the first lifting tool 160 may include the mounting plate 160A, the threaded rod 160B, the fastener rod 195, the knob 160C and a pad 160D. In an exemplary embodiment, the first lifting tool 160 may also include the handle 160F. In this case, the first lifting tool 160 includes the mounting plate 160A, the threaded rod 160B, the fastener rod 195, the knob 160C, the pad 160D and the handle 160F.
The first lifting tool 160 may be referred to as a torque initiated lifting tool. As described with reference to
In an exemplary embodiment, the first lifting tool 160 may be applicable to the process chambers including the process chambers 120. In this case, the first lifting tool 160 may be attached to lids of the process chambers 120, for example.
The process system 100 of
While the present inventive concept has been shown and described with reference to exemplary embodiments thereof, it will be apparent to those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.
