Rotating stage device for precision press apparatus

Abstract

The present invention relates to a rotary stage mechanism for a precision press device. The rotary stage comprises a rotary table that rotates around a vertical axis and a stage body that supports the rotation of the rotary table by housing it in an internal space with the rotary table partially pulled down and rotates the rotary table upon power application. The stage housing is fixed to the lower side of a lifting block that moves up and down along a vertical axis by a vertical drive, and fixes the stage body by housing the rotary stage in an internal space with an open lower side. The rotary block is fixed to the upper side of a compression head and is inserted through the lower opening of the stage housing to be fixed coaxially with the rotary table. A bearing for the rotary block is mounted between the stage housing and the rotary block to support the rotation of the rotary block.

Description

Technology Field

[0001] The present invention relates to a rotary stage mechanism employed in a precision press device, and more specifically, to a rotary stage mechanism that enables a compression head moving along a vertical axis to be rotated and aligned around the vertical axis. Background Technology

[0002] A semiconductor chip thermal compression bonder is a type of precision press device that picks up a semiconductor chip using a compression head and bonds it to a substrate. In the case of a semiconductor chip with bumps formed on its underside, the semiconductor chip thermal compression bonder bonds the chip by heating it and pressing the bumps against the connection terminals of the substrate.

[0003] A semiconductor chip thermal compression bonder may include a vertical drive mechanism for vertically lowering a compression head to compress a semiconductor chip onto a substrate along a vertical Z-axis, and a horizontal drive mechanism for horizontally moving the compression head to align the semiconductor chip along the X-axis and Y-axis on a horizontal plane. Additionally, the semiconductor chip thermal compression bonder may include a rotary drive mechanism for rotating the compression head to align the semiconductor chip by rotating it around the Z-axis.

[0004] According to a conventional example, it is composed of a combination of a rotary drive mechanism and a vertical drive mechanism. The rotary drive mechanism includes a servo motor and a harmonic drive that reduces and outputs the rotational speed of the servo motor. The vertical drive mechanism includes a pneumatic cylinder having a rotary function. The pneumatic cylinder having a rotary function is configured to move a piston linearly by pneumatic pressure and to move the piston rotationally by an external rotational force. The pneumatic cylinder supports the rotational movement of the piston by air bearings within the cylinder body.

[0005] The pneumatic cylinder is positioned to move the piston in the vertical direction and is equipped with a compression head at the bottom of the piston. The top of the piston is splined to the output shaft of the harmonic drive.

[0006] In the case of the aforementioned conventional example, there are disadvantages such as a high vertical height and a high center of gravity due to structural limitations requiring the installation of a heavy servo motor and harmonic drive on the upper side of the pneumatic cylinder for rotational drive, a large rotation angle transmission error due to spline backlash, and the need for an expensive pneumatic cylinder requiring precision machining. The problem to be solved

[0007] The objective of the present invention is to provide a rotary stage mechanism for a precision press device capable of precisely adjusting the rotation angle of a compression head with a miniaturized and lightweight structure. means of solving the problem

[0008] A rotary stage mechanism for a precision press device according to the present invention for achieving the above objectives comprises a rotary stage, a stage housing, a rotary block, and a bearing for the rotary block. The rotary stage comprises a rotary table that rotates around a vertical axis and a stage body that supports the rotation of the rotary table by housing it in an internal space with the rotary table partially pulled down and rotates the rotary table upon power application. The stage housing is fixed to the lower side of a lifting block that moves up and down along a vertical axis by a vertical drive, and fixes the stage body by housing the rotary stage in an internal space with an open lower side. The rotary block is fixed to the upper side of a compression head and is inserted through the lower opening of the stage housing to be fixed coaxially with the rotary table. A bearing for the rotary block is mounted between the stage housing and the rotary block to support the rotation of the rotary block.

[0009] Here, the stage body may be configured to rotate the rotating table by generating ultrasonic vibrations through the inverse piezoelectric effect of the piezoelectric element upon power application.

[0010] A bearing for a rotating block can be composed of a cross-roller bearing in which rollers are arranged orthogonally between the inner ring and the outer ring. Effects of the invention

[0011] According to the rotary stage mechanism for a precision press device of the present invention, even under working conditions where a significant amount of compression force is applied to an object by a compression head, an ultrasonic motor type rotary stage can be applied as the rotary stage, thereby allowing the rotation angle of the compression head to be precisely adjusted with a compact and lightweight structure. Brief explanation of the drawing

[0012] FIG. 1 is a perspective view of a rotary stage mechanism for a precision press device according to one embodiment of the present invention. Figure 2 is an exploded perspective view of Figure 1. Figure 3 is a cross-sectional view of Figure 1. Specific details for implementing the invention

[0013] The present invention will be described in detail below with reference to the attached drawings. Here, the same reference numerals are used for identical components, and repetitive descriptions and detailed descriptions of known functions and components that could unnecessarily obscure the essence of the invention are omitted.

[0014] The embodiments of the present invention are provided to more fully explain the invention to those with average knowledge in the art. Accordingly, the shapes and sizes of the elements in the drawings may be exaggerated for clearer explanation.

[0015] FIG. 1 is a perspective view of a rotary stage mechanism for a precision press device according to one embodiment of the present invention. FIG. 2 is an exploded perspective view of FIG. 1. FIG. 3 is a cross-sectional view of FIG. 1.

[0016] Referring to FIGS. 1 to 3, a rotary stage mechanism (100) for a precision press device according to one embodiment of the present invention includes a rotary stage (110), a stage housing (120), a rotary block (130), and a bearing (140) for the rotary block.

[0017] The rotating stage (110) comprises a rotating table (111) and a stage body (116). The rotating table (111) rotates around a vertical axis. The rotating table (111) may be formed in such a way that a table column (113) is coaxially connected to one side of a table disk (112). The table disk (112) has a circular cross-section. The table column (113) has an outer diameter smaller than the outer diameter of the table disk (112). The rotating table (111) may have a hollow that penetrates vertically through the center.

[0018] The stage body (116) accommodates the rotating table (111) in an internal space with the rotating table (111) partially pulled out downwards to support the rotation of the rotating table (111), and rotates the rotating table (111) according to the application of power.

[0019] The stage body (116) can insert the table column (113) of the rotating table (111) into the hollow that penetrates vertically, and can insert the table disk (112) of the rotating table (111) into the groove formed along the periphery of one opening.

[0020] The stage body (116) may be positioned so that the table disk (112) faces downward. The stage body (116) may support the rotation of the table column (113) by means of a bearing mounted on its inner surface. The outer shape of the stage body (116) may be approximately a cuboid. A hole communicating with the hollow of the rotating table (111) may be formed on the upper surface of the stage body (116).

[0021] The rotary stage (110) may be configured as a rotary stage using an ultrasonic motor as a driving source. In this case, the rotary stage (110) can precisely rotate the rotary table (111) with a compact and lightweight structure.

[0022] The stage body (116) may be configured to generate ultrasonic vibrations through the inverse piezoelectric effect of a piezoelectric element upon power application to rotate the rotating table (111). The piezoelectric element of the stage body (116) may be configured in various known ways to rotate the rotating table (111).

[0023] The stage housing (120) is fixed to the lower side of the lifting block (10), which moves up and down along a vertical axis by means of a vertical actuator. The lifting block (10) is lowered by means of a vertical actuator and, together with the rotating stage mechanism (100), lowers the compression head (20), thereby enabling the compression head (20) to compress an object. The vertical actuator may be configured to include various known linear actuators.

[0024] The stage housing (120) has an internal space and is open at the bottom to accommodate the rotating stage (110) and fix the stage body (116). The stage housing (120) may include a housing base (121) and a pair of housing side plates (126).

[0025] The housing base (121) can pass the upper portion of the rotating block (130) through the hollow that penetrates vertically. The housing base (121) has an upper groove formed along the upper periphery of the hollow, having an inner diameter larger than the outer diameter of the table disk (112), so as to accommodate the table disk (112).

[0026] The housing base (121) can fix the stage body (116) by bolting while supporting the lower surface of the stage body (116) on its upper surface. The housing base (121) may have an outer ring mounting groove (122) formed along the lower periphery of the hollow, having an inner diameter larger than the inner diameter of the hollow, to mount a bearing (140) for the rotating block. The outer ring of the bearing (140) for the rotating block is inserted into and fixed in the outer ring mounting groove (122).

[0027] The housing side plates (126) extend upward from the mutually facing edges of the housing base (121) to form an internal space for accommodating a rotating stage (110) on the upper side of the housing base (121).

[0028] The inner surfaces of the housing side plates (126) can be in contact with the outer surfaces of the sides of the stage body (116) to stably support the stage body (116). The upper surfaces of the housing side plates (126) can be fixed by bolting while in contact with the lower surface of the lifting block (10).

[0029] Grooves for bolting with the lifting block (10) may be formed on the outer surface of the housing side plate (126). The lower side of each groove is formed in an open shape for inserting a bolt, and a hole for fastening a bolt may be formed on the upper side of each groove.

[0030] The rotating block (130) is fixed to the upper side of the compression head (20). The rotating block (130) may be equipped with a load cell (30) between it and the compression head (20). The load cell (30) measures the compression force applied to the object as the compression head (20) descends. When the compression head (20) applies a compression force to the object, the load cell (30) can measure the compression force by measuring the vertical reaction force applied from the object to the compression head (20).

[0031] The rotation block (130) is inserted through the lower opening of the stage housing (120) and fixed coaxially to the rotation table (111). The rotation block (130) may include an upper rotation block portion (131) and a lower rotation block portion (136).

[0032] The upper rotating block portion (131) may be arranged coaxially with the table disk (112). The upper rotating block portion (131) may be fixed by bolting so that its upper surface is in contact with the lower surface of the table disk (112). The upper rotating block portion (131) may have an upper mounting groove (132) for an inner ring formed along its lower outer circumference to mount a bearing (140) for the rotating block.

[0033] The lower rotating block (136) may be arranged coaxially with the upper rotating block (131). The upper surface of the lower rotating block (136) may be supported by contacting the lower surface of the upper rotating block (131). The lower rotating block (136) may have a screw hole in the center that is fastened to the threaded portion of a bolt. The upper rotating block (131) may have a fastening hole in the center into which the head of a bolt is inserted.

[0034] The lower rotating block (136) and the upper rotating block (131) can be fixed to each other by fastening bolts through screw holes and fastening holes. The bolts can be inserted from the top through the upper hole of the stage body (116) and the hollow of the rotating table (111).

[0035] The lower rotating block portion (136) can be fixed to the upper rotating block portion (131) with a pin so as not to slip in the rotational direction relative to the upper rotating block portion (131). The lower rotating block portion (136) may have a lower mounting groove (137) for the inner ring formed along the upper outer circumference to mount a bearing (140) for the rotating block. The lower mounting groove (137) for the inner ring, together with the upper mounting groove (132) for the inner ring, inserts and fixes the inner ring of the bearing (140) for the rotating block.

[0036] In this way, the rotating block (130) is structured to be divided into upper and lower rotating block parts (131, 136) and assembled, so that the bearing (140) for the rotating block can be easily installed between the rotating block (130) and the stage housing (120).

[0037] A bearing (140) for a rotating block is mounted between the stage housing (120) and the rotating block (130) to support the rotation of the rotating block (130). The outer ring of the bearing (140) for the rotating block is fixed in the outer ring mounting groove (122) of the housing base (121), and the inner ring of the bearing (140) for the rotating block can be fixed in the upper and lower mounting grooves (132, 137) for the inner ring of the upper and lower rotating block parts (131, 136).

[0038] For example, the bearing (140) for a rotating block may be composed of a cross-roller bearing in which rollers are arranged orthogonally between the inner ring and the outer ring. Since the cross-roller bearing can handle axial loads, radial loads, and moment loads simultaneously, it may be advantageous for miniaturization and space saving. Additionally, the cross-roller bearing may be useful in environments requiring high precision and high rigidity. The cross-roller bearing may be made of various known configurations.

[0039] An example of operation for the rotary stage mechanism (100) for the aforementioned precision press device is described as follows.

[0040] After the compression head (20) picks up an object, such as a semiconductor chip, the rotation stage (110) rotates the rotation table (111) around the vertical axis in a no-load state and adjusts the rotation angle of the compression head (20) through the rotation block (130), thereby aligning the semiconductor chip to a set rotation angle.

[0041] Subsequently, the lifting block (10) is lowered by a vertical drive to lower the compression head (20) together with the rotating stage (110) and compress the semiconductor chip onto the substrate. The compression head (20) can apply a compression force of several hundred N in the vertical direction to the semiconductor chip. At this time, the rotating stage (110) is controlled so as not to rotate the rotating table (111).

[0042] When the compression head (20) applies a compression force to the semiconductor chip, a vertical reaction force corresponding to the compression force acts from the semiconductor chip to the compression head (20). As shown by the arrow in FIG. 3, the vertical reaction force is transmitted in the order of the compression head (20), load cell (30), bearing for the rotating block (140), stage housing (120), and lifting block (10), so it is not transmitted to the rotating stage (110). Since the vertical reaction force does not act directly on the rotating stage (110), damage to parts such as bearings configured inside the rotating stage (110) can be prevented.

[0043] Thus, according to the rotary stage mechanism (100) for a precision press device of the present embodiment, even under working conditions where a significant amount of compression force is applied to an object by the compression head (20), an ultrasonic motor type rotary stage can be applied as the rotary stage (110), so the rotation angle of the compression head (20) can be precisely adjusted with a compact and lightweight structure.

[0044] The present invention has been described with reference to an embodiment illustrated in the accompanying drawings, but this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the true scope of protection of the present invention should be determined only by the appended claims. Explanation of the symbols

[0045] 10.. Elevator Block 20..Crimping head 30..load cell 100..Rotary stage mechanism for precision press devices 110.. Rotating stage 111..Rotating table 112..Table Disk 113..Table pillar 116..Stage main body 120..Stage Housing 121..Housing Base 122.. Mounting groove for outer ring 126..Housing side panel 130..Rotating Block 131..Upper rotating block part 132..Upper mounting groove for inner ring 136..Lower rotating block part 137..Lower mounting groove for inner ring 140..Bearing for rotary blocks

Claims

Claim 1 A rotary stage mechanism for a precision press device comprising: a rotary table that rotates around a vertical axis, and a stage body that accommodates the rotary table in a partially pulled-out state to support the rotation of the rotary table and rotates the rotary table upon power application; a stage housing that is fixed to the lower side of a lifting block that moves up and down along a vertical axis by a vertical drive, and that accommodates the rotary stage with an internal space and an open lower side to fix the stage body; a rotary block that is fixed to the upper side of a compression head and inserted through the lower opening of the stage housing to be fixed coaxially to the rotary table; and a bearing for the rotary block that is mounted between the stage housing and the rotary block to support the rotation of the rotary block. Claim 2 A rotary stage mechanism for a precision press device according to claim 1, characterized in that the bearing for the rotary block is composed of a cross roller bearing in which rollers are arranged orthogonally between the inner ring and the outer ring. Claim 3 A rotary stage mechanism for a precision press device according to claim 1, characterized in that the stage body is configured to generate ultrasonic vibrations by the inverse piezoelectric effect of a piezoelectric element upon power application to rotate the rotary table.

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