Sorbent device

Abstract

The present application provides an adsorption device, which can prevent burrs and notches from being generated on the leaving side of the end face when cutting wafers from the end face of a silicon ingot. The adsorption device (100) of the present application is an adsorption device adsorbed to the end face (106) of a columnar silicon ingot (104), and has a plurality of adsorption pads (114a-114i) adsorbed to the end face when cutting wafers from the end face of the silicon ingot using a band saw (108). The adsorption pads are more arranged on the leaving side (F) than on the entering side (E) with respect to the cutting direction (A) of the band saw.

Description

Technical Field

[0001] This invention relates to an adsorption device for adsorbing onto the end face of a columnar silicon ingot. Background Technology

[0002] Wafers are obtained by cutting them from the end face of a cylindrical silicon ingot, which is the raw material for semiconductor devices. The end face of the silicon ingot is cut by a cutting tool (cutting blade) such as a band saw, and during the cutting process, it is adsorbed by an adsorption device.

[0003] Patent Document 1 describes a cutting device for cutting a wafer from a columnar material (silicon ingot). In this cutting device, an air cushion is arranged at a predetermined interval from the end face of the wafer, and the wafer is cut from the columnar material while attracting and holding the end face of the wafer to the air cushion side.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 9-290416 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] However, during the cutting process of cutting the end face of silicon ingots, burrs and gaps are easily generated on the departure side of the end face of the silicon ingot based on the cutting direction of the cutting tool (especially when the cutting ends). This can sometimes damage the quality of the wafer.

[0009] The cutting device in Patent Document 1 simply cuts the wafer while holding the end face of the wafer to the air cushion side, without taking any measures to address the issue of burrs and gaps being generated on the departure side of the silicon ingot end face.

[0010] The purpose of this invention is to provide an adsorption device that can prevent burrs and gaps from being generated on the departure side of the end face when cutting wafers from the end face of a silicon ingot.

[0011] Solution for solving the problem

[0012] To address the aforementioned issues, a representative structure of the adsorption device according to the present invention is provided in which a plurality of adsorption pads are adsorbed onto the end face of a columnar silicon ingot when a wafer is cut from the end face of the silicon ingot using a cutting tool, and the adsorption pads are arranged more on the exit side relative to the entry side of the cutting direction of the cutting tool.

[0013] When dividing the end face of the silicon ingot into two regions, an entry side and an exit side, the adsorption area of ​​the adsorption pad is preferably set such that the adsorption area of ​​the exit side is larger than the adsorption area of ​​the entry side.

[0014] When the end face of the silicon ingot is divided into four regions from the entry side to the exit side, the adsorption area of ​​the adsorption pad is preferably set such that the region closest to the exit side is larger among the four regions.

[0015] Preferably, multiple adsorption pads are arranged along the edge of the silicon ingot on the end face of the silicon ingot, centered on the position where the cutting tool last leaves.

[0016] The effects of the invention

[0017] According to the present invention, an adsorption device is provided that can prevent burrs and gaps from being generated on the departure side of the end face when cutting a wafer from the end face of a silicon ingot. Attached Figure Description

[0018] Figure 1 This is a schematic diagram showing the structure of the cutter of the adsorption device according to an embodiment of the present invention.

[0019] Figure 2 It is shown Figure 1 A diagram of the adsorption device.

[0020] Figure 3 It is shown Figure 2 A diagram showing the internal structure of the adsorption device.

[0021] Figure 4 It is shown Figure 2 A diagram showing the configuration of multiple adsorption pads in the adsorption device. Detailed Implementation

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific values ​​shown in these embodiments are merely examples for ease of understanding and are not intended to limit the present invention unless otherwise stated. Furthermore, in this specification and the accompanying drawings, elements having substantially the same function or structure are labeled with the same reference numerals, thereby omitting repeated descriptions. Additionally, elements not directly related to the present invention are omitted from the illustrations.

[0023] Figure 1 This is a schematic diagram showing the structure of the cutting machine 102 of the adsorption apparatus 100 according to an embodiment of the present invention. The cutting machine 102 is an apparatus for cutting the end face 106 of a columnar silicon ingot 104, which is a raw material for semiconductor elements. In addition, wafers (including sample wafers with a thickness of, for example, 1.3 mm) are obtained by cutting from the end face 106 of the silicon ingot 104.

[0024] The cutting device 102 includes an adsorption device 100, a band saw 108 as the cutting tool, and a recovery device 110. The end face 106 of the silicon ingot 104 is cut by the band saw 108 along the cutting direction shown by arrow A in the figure, and is adsorbed by the adsorption device 100 during the cutting. The figure also shows a groove 112 generated during the cutting of the end face 106 of the silicon ingot 104.

[0025] The adsorption device 100 includes an adsorption pad 114. The adsorption pad 114 adsorbs onto the end face 106 when the wafer is cut from the end face 106 of the silicon ingot 104. The recycling device 110 is a device for recycling the cut wafer. The recycling device 110 includes a base 116 installed on the ground of a factory or the like, a horizontal moving arm 118, and a vertical moving arm 120.

[0026] The horizontal moving arm 118 of the recovery device 110 is disposed on the upper part of the base 116 and is capable of moving horizontally. The vertical moving arm 120 is disposed on the horizontal moving arm 118 and is capable of moving vertically relative to the horizontal moving arm 118. Additionally, the adsorption device 100 is mounted on the front end 120a of the vertical moving arm 120. The recovery device 110 drives the horizontal moving arm 118 and the vertical moving arm 120 to move the adsorption device 100, which adsorbs the diced wafers, to a predetermined position, thereby recovering the wafers.

[0027] Figure 2 It is shown Figure 1 The diagram shows the adsorption device 100. Figure 2 of (a) Figure 2 (b) and Figure 2 (c) are top view, front view and side view of the adsorption device 100, respectively. The adsorption device 100 has an adsorption pad 114, a head 122 and a pipe connector 124. The adsorption pad 114 includes a plurality of (in this case, nine) adsorption pads 114a to 114i.

[0028] Multiple adsorption pads 114a-114i are disposed on the front surface (silicon ingot 104 side) of the head 122, and a pipe connector 124 is mounted on the back side. A conduit from... Figure 1 The vertical moving arm 120 shown has a piping 126 extending from its front end 120a. The piping 126 is also connected to a vacuum pump (not shown) or similar device.

[0029] Figure 3 It means Figure 2 A diagram showing the internal structure of the adsorption device 100. The diagram illustrates... Figure 2 The internal structure of the adsorption pad 114a and its surrounding area. A cylinder portion 128, a clamping sleeve 130, and a clamping portion 132 are disposed inside the head 122. Furthermore, passages 134, 136, and 138 are provided in the head 122.

[0030] The cylinder section 128 moves forward by introducing forward air 134a into the passage 134, and moves backward by introducing backward air 136a into the passage 136. Additionally, when clamping air 138a is introduced into the passage 138, the cylinder section 128 is clamped in a predetermined position by the clamping part 132 via the clamping sleeve 130. Furthermore, the suction pad 114a is connected to the cylinder section 128, thus allowing it to move forward or backward as the cylinder section 128 moves.

[0031] Furthermore, an attraction passage 140 is formed inside the cylinder section 128, connecting the pipe connector 124 to the adsorption pad 114a. Moreover, the pipe connector 124... Figure 1 The piping 126 shown is connected to a vacuum pump (not shown). Therefore, by operating the vacuum pump, air can be drawn from the adsorption pad 114 and adsorbed onto the end face 106.

[0032] Then, when the wafer is cut from the end face 106 of the silicon ingot 104, Figure 1 The recovery device 110 shown drives the horizontal moving arm 118 and the vertical moving arm 120 as described above, moving the adsorption device 100 with the wafer adsorbed to a predetermined position. Thus, the adsorption device 100 can recover the wafer while it is adsorbed onto the adsorption pad 114a.

[0033] Figure 4 It is shown Figure 2 A diagram showing the arrangement of multiple adsorption pads 114a to 114i of the adsorption device 100. Dashed lines B and C in the diagram represent the end faces 106 of silicon ingots 104 with diameters of 315 mm and 203 mm, respectively (see reference). Figure 1 The edge of the silicon ingot 104. Additionally, dimension D represents the diameter of the end face 106 of the silicon ingot 104 shown by the dashed line B. Furthermore, the adsorption pads 114a to 114i are the same size, and therefore have the same adsorption area.

[0034] The adsorption pads 114a to 114i are more frequently positioned on the exit side (see arrow F) relative to the entry side (see arrow E) of the cutting direction indicated by arrow A of the band saw 108. Figure 4 In the example, the end face 106 of the silicon ingot 104 shown at point B is divided into two regions: an entry-side region Ra and an exit-side region Rb, both with a size of D / 2. At this time, half of the entry-side region Ra is provided with adsorption pads 114e, 114f, 114g, and two adsorption pads 114h, 114i.

[0035] On the other hand, in the region Rb on the departure side, adsorption pads 114e, 114f, and 114g are arranged on the departure side, covering half of the departure side, and four adsorption pads 114a, 114b, 114c, and 114d. Therefore, the total adsorption area of ​​adsorption pads 114a to 114i is set such that the region Rb on the departure side is larger than the region Ra on the entry side. In other words, adsorption pads 114 are concentrated on the departure side of the end face 106 of the silicon ingot 104 based on the band saw 108 (especially when the cutting is completed).

[0036] Therefore, according to the adsorption device 100, during the cutting process of the end face 106 of the silicon ingot 104, the adsorption pad 114 can adsorb and stably maintain the departure side of the end face 106. Therefore, burrs and gaps are less likely to be generated on the departure side of the end face 106 of the silicon ingot 104, and the quality of the wafer can be maintained.

[0037] Furthermore, in the adsorption device 100, along the edge of the silicon ingot 104 indicated by the dashed line B on the end face 106 of the silicon ingot 104, a plurality of adsorption pads 114a and 114b are arranged with the position G where the band saw 108 last leaves the edge as the center. Additionally, along the edge of the silicon ingot 104 indicated by the dashed line C, a plurality of adsorption pads 114a, 114b, 114c, and 114d are arranged with the position H where the band saw 108 last leaves the edge as the center.

[0038] Thus, in the adsorption device 100, adsorption pads 114 are centrally arranged along the edge of the silicon ingot 104 on the end face 106 of the silicon ingot 104, with the last exit position G and H of the band saw 108 as the center. As a result, the adsorption pads 114 can adsorb and stably hold the exit side of the end face 106 of the silicon ingot 104.

[0039] Furthermore, the layout of the adsorption pads 114 can be appropriately modified. For example, the end face 106 of the silicon ingot 104 can be divided into four regions Rc, Rd, Re, and Rf, each with a D / 4 dimension, from the entry side towards the exit side. Additionally, the adsorption pads 114d and 114c can be positioned closer to the exit side of the end face 106 of the silicon ingot 104 and placed in region Rf. In this case, the total adsorption area of ​​the adsorption pads 114a to 114i is set such that the region Rf closest to the exit side among the four regions Rc, Rd, Re, and Rf is the largest.

[0040] In this way, by concentrating the adsorption pad 114 in the region Rf closest to the departure side of the end face 106 of the silicon ingot 104, the adsorption pad 114 can be used to adsorb and stably maintain the departure side of the end face 106 of the silicon ingot 104.

[0041] Furthermore, in the aforementioned cutting device 102, a wafer is obtained by cutting the end face 106 of the silicon ingot 104 with a band saw 108, but it is not limited to this. As an example, it can also be used instead of the silicon ingot 104 when cutting thin sheets from the end face of a very brittle material, and the thin sheet can also be adsorbed using an adsorption pad 113. In addition, the present invention can also be appropriately applied when a wire saw is used instead of a band saw.

[0042] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to these examples. It will be apparent to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and it should be understood that these modifications or alterations also fall within the technical scope of this disclosure.

[0043] Industrial availability

[0044] This invention can be used as an adsorption device for adsorbing onto the end face of a columnar silicon ingot.

[0045] Explanation of reference numerals in the attached figures

[0046] 100. Adsorption device; 102. Cutting machine; 104. Silicon ingot; 106. End face of silicon ingot; 108. Band saw; 110. Recycling device; 112. Tank; 114, 114a-114i. Adsorption pad; 116. Base; 118. Horizontal moving arm; 120. Vertical moving arm; 120a. Front end of vertical moving arm; 122. Head; 124. Pipe fitting; 126. Piping; 128. Cylinder section; 130. Clamping sleeve; 132. Clamping part; 134, 136, 138. Passage; 134a. Forward air; 136a. Reverse air; 138a. Clamping air; 140. Suction passage

Claims

1. An adsorption device for adsorbing onto the end face of a columnar silicon ingot, characterized in that, The adsorption device has multiple adsorption pads that adhere to the end face of the silicon ingot when a cutting tool is used to cut the wafer. The suction pad is more often positioned on the exit side than on the entry side of the cutting direction of the cutting tool.

2. The adsorption device according to claim 1, characterized in that, When the end face of the silicon ingot is divided into two regions, the entry side and the exit side, The adsorption area of ​​the adsorption pad is set such that the adsorption area of ​​the region on the departure side is larger than the adsorption area of ​​the region on the entry side.

3. The adsorption device according to claim 1 or 2, characterized in that, When the end face of the silicon ingot is divided into four regions from the entry side to the exit side, The adsorption area of ​​the adsorption pad is set such that the area closest to the departure side is larger among the four regions.

4. The adsorption device according to claim 1, characterized in that, On the end face of the silicon ingot, along the edge of the silicon ingot, a plurality of the adsorption pads are arranged centered on the position where the cutting tool last leaves.

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