JP2004273635A - Dicing equipment and dicing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide dicing equipment and a dicing method in which a substrate can be diced stably even when a substrate having a plurality of circuit elements formed integrally is warped. <P>SOLUTION: The dicing equipment 100 for cutting a wafer 50 having a plurality of IC chips formed integrally into individual IC chips comprises a stage 5 for securing the circumferential edge part of the wafer 50, a pusher 3 for supporting the cutting part of the wafer 50 having a circumferential edge part being secured by the stage 5 from one side, and a blade 1 for dicing the cutting part of the wafer 50 having one side being supported by the pusher 3 from the other side. Even if the wafer 50 is warped, the cutting part of the wafer 50 can be supported continually by means of the pusher 3. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a dicing apparatus and a dicing method, and more particularly to a dicing apparatus and a dicing method suitable for dicing a semiconductor wafer having an active surface covered with a sealing resin into a plurality of chips. It is.
[0002]
[Prior art]
FIG. 5 is a sectional view showing a configuration example of a dicing apparatus 90 according to a conventional example. In FIG. 5, a semiconductor wafer (hereinafter, referred to as a wafer) 50 to be diced has an upper layer portion and a lower layer portion. The lower layer of the wafer 50 is a silicon layer on which a number of integrated circuit (IC) chips are built. The upper layer portion of the wafer 50 is a thick resin layer for sealing the active surface side of the IC chip. The ball electrode 52 of the IC is exposed from the resin layer. In the dicing apparatus 90, the resin-sealed wafer 50 is set on a stage 95.
[0003]
FIG. 6 is a plan view showing a configuration example of the stage 95. The surface of the stage 95 on which the wafer 50 is placed is flat. At a specific position 97 where the wafer 50 is placed, a plurality of intake holes 96 are provided. The suction holes 96 are connected to an exhaust pump (not shown), and the wafer 50 is drawn toward the stage 95 by sucking air from the suction holes 96.
[0004]
In the dicing process using the dicing apparatus 90, the dicing blade 1 rotating at a high speed is applied to a scribe line of the wafer 50 to perform a dicing operation. The wafer 50 is diced along scribe lines provided on four sides of the IC chip, and divided into ultra-small packages such as W-CSP (wafer-chip size package).
[0005]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 5-190664 [Patent Document 2]
JP-A-62-151306
[Problems to be solved by the invention]
By the way, the silicon layer, which is the lower layer of the wafer 50, is one in which many IC (integrated circuit) chips are built through a wafer process involving high-temperature processing. For this reason, the silicon layer is often warped. In particular, when there is a thick resin layer on the active surface side of the silicon layer, stress in the contraction direction acts on the silicon layer by the resin layer, and therefore, the warpage of the wafer 50 tends to increase.
[0007]
Therefore, when dicing the wafer 50, a small space is often generated between the wafer 50 and the stage 95, and the entire surface of the wafer 50 cannot be suction-supported. When the dicing blade 1 hits a part of the wafer 50 having a small space between the wafer and the stage 95 in particular, the wafer 50 flaps up and down around the part, and the chipping of the silicon layer occurs. (Microcracks) may occur. If chipping occurs in the silicon layer, the reliability of the IC chip decreases.
[0008]
Therefore, the present invention is to solve such a problem of the prior art, and is capable of stably dicing this substrate even when a substrate on which a plurality of circuit elements are integrally formed is warped. It is an object of the present invention to provide a dicing apparatus and a dicing method.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problem, a first dicing apparatus according to the present invention is a dicing apparatus that cuts a substrate having a plurality of circuit elements formed integrally and divides the substrate into individual circuit elements. Fixing means for fixing the portion, supporting means for supporting the cut portion of the substrate to which the peripheral portion is fixed by the fixing means from one side, and the cut portion which is supported on one side by the support means. Cutting means for cutting from the side.
[0010]
In the second dicing apparatus according to the present invention, in the above-described first semiconductor device, a sheet member for holding the substrate is attached to one side of the substrate, and the supporting unit presses the sheet member. Thus, the cut portion of the substrate is supported from one side.
According to a third dicing apparatus of the present invention, in the above-mentioned second semiconductor device, a rolling member having a smooth outer peripheral surface is provided at a portion of the supporting means for pressing the sheet member, and a substrate is provided on the outer peripheral surface of the rolling member. Is supported from one side.
[0011]
A fourth dicing apparatus according to the present invention, in the above-described second semiconductor device, has a sphere that can rotate in all directions at a position where the sheet member of the support means is pressed, and an outer peripheral surface of the sphere forms a substrate. The cutting portion is supported from one side.
Here, a disc-shaped cutter called a dicing blade is usually used as a cutting means of the dicing device. The dicing blade scans a cut portion of the substrate while rotating at a high speed, and cuts the substrate into individual circuit elements.
[0012]
According to the first to fourth dicing apparatuses according to the present invention, only a peripheral portion of a substrate on which a plurality of circuit elements are integrally formed is fixed by fixing means. One side of the cut portion of the substrate floating from the fixing means is locally supported by the support means. The cutting means abuts on the other side of the part to be cut which is locally supported by the support means. In this state, the supporting means moves relative to the substrate in conjunction with the cutting means, and the cut portion is cut by being sandwiched between the supporting means and the cutting means.
[0013]
Therefore, even when the substrate is warped, the cut portion of the substrate can be supported without interruption, and the force applied to the cut portion from the cutting means can be received by the support means. Thereby, the substrate can be stably diced, and the occurrence of chipping can be reduced.
The dicing method according to the present invention is a dicing method for cutting a substrate on which a plurality of circuit elements are integrally formed and dividing the substrate into individual circuit elements, wherein a sheet member for holding a substrate is attached to one side of the substrate. A step of fixing only the peripheral portion of the substrate to which the sheet member is attached, a step of pressing the sheet member to support the cut portion of the substrate from one side, and a step of supporting the cut portion of the substrate from one side. Cutting the cutting site from the other side. According to the dicing method according to the present invention, even when the substrate is warped, the substrate can be diced stably, and the occurrence of chipping can be reduced.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a dicing apparatus and a dicing method according to an embodiment of the present invention will be described with reference to the drawings.
(1) First Embodiment FIG. 1 is a sectional view showing a configuration example of a dicing apparatus 100 according to a first embodiment of the present invention. The dicing apparatus 100 is an apparatus for cutting a semiconductor wafer 50 on which a large number of IC chips are integrally formed and dividing the semiconductor wafer into individual circuit elements.
[0015]
As shown in FIG. 1, the dicing apparatus 100 includes a stage 5 for fixing the periphery of a semiconductor wafer 50 while adsorbing the semiconductor wafer 50, and a semiconductor wafer 50 whose periphery is fixed by the stage 5 along a scribe line. The apparatus includes a pusher 3 that supports the cut portion from below, and a dicing blade (hereinafter, referred to as a blade) 1 that cuts the cut portion supported by the pusher 3 from above.
[0016]
As described with reference to FIG. 5, for example, the semiconductor wafer 50 is provided with a thick resin layer on a silicon layer in which a large number of IC chips are formed, and the ball electrodes 52 of the IC are exposed from the resin layer. Things. In FIG. 1, the diameter of the semiconductor wafer 50 is, for example, about 12 inches (about 300 mm). The distance (pitch) between the ball electrodes 52 is, for example, about 300 μm.
[0017]
The dicing sheet 10 is stuck on the opposite side of the ball electrode 52. On the wafer 50 side of the dicing sheet 10, a UV-curable adhesive is applied. In the dicing step, the wafers 50 before and after the division are adhesively held by the dicing sheet 10. As shown in FIG. 1, the wafer 50 is set on the stage 5 with the dicing sheet 10 facing downward.
[0018]
The stage 5 holds the wafer 50 on which the dicing sheet 10 is stuck at a predetermined height with respect to the blade 1 and the pusher 3, and is designed to fix a peripheral portion of the wafer 50. As shown in FIG. 1, the dicing sheet 10 side, which is the peripheral portion of the wafer 50, is placed on the stage 5. The surface of the stage 5 on which the wafer 50 is mounted is flat without irregularities.
[0019]
Further, as shown in FIG. 2, a plurality of intake holes 8 are provided at a position (hereinafter, referred to as a wafer mounting position) 7 of the stage 5 where the wafer 50 is mounted. These intake holes 8 are connected to an exhaust pump (not shown). By operating this exhaust pump and sucking in air from the intake holes 8, the peripheral portion of the wafer 50 can be attracted to the stage 5 and fixed.
[0020]
Further, an opening 9 having a substantially circular shape in plan view is provided inside the wafer mounting position 7. The diameter of the wafer mounting position 7 is, for example, about 300 mm corresponding to the size of the semiconductor wafer 50. The diameter of the opening 9 is, for example, about 280 mm. The diameter of the intake holes 8 is about 2 mm, and about 20 to 40 are provided at equal intervals. The stage 5 is designed to be moved in the XY direction in FIG. 1 by a motor (not shown) or the like.
[0021]
The blade 1 is a so-called diamond cutter in which a bonding material containing diamond particles is formed in a disk shape. The blade 1 is mounted on a blade holder 2 so as to be rotatable at a predetermined angular velocity on the YZ plane in FIG. 1 by a motor or the like (not shown). The blade holder 2 that supports the blade 1 is designed to be movable in the Z direction in FIG. 1 by a motor (not shown) while supporting the blade 1.
[0022]
The pusher 3 is provided below an opening 9 provided in the stage 5, as shown in FIG. The pusher 3 has a distal end portion 4 in a rod shape, and the shape of the XY cross section is, for example, substantially circular. In addition, a portion of the front end portion 4 that presses the dicing sheet 10 has an R-shape with a sharp corner. The tip 4 has, for example, a main body made of a metal such as stainless steel, and a low friction resin such as a fluororesin is applied on the main body. The tip 4 of the pusher is coaxial with the blade 1 and is designed to be movable in the Z direction by a motor (not shown).
[0023]
When the semiconductor wafer 50 is cut into individual packages using the dicing apparatus 100 configured as described above, the dicing apparatus 100 is operated, for example, as follows.
First, the suction holes 8 (see FIG. 2) of the suction table 5 are set in a suction state. In this state, the dicing sheet 10 side of the wafer 50 is placed on the wafer mounting position 7 of the stage 5 (see FIG. 2). As a result, the peripheral portion of the wafer 50 is fixed to the stage 5. Next, the stage 5 is moved in the XY direction in FIG. 1 to adjust the position so that the cut portion of the wafer 50 is located below the blade 1, that is, on the tip 4 of the pusher.
[0024]
Next, the tip portion 4 of the pusher is moved upward to press the dicing sheet 10 to locally support the cut portion of the wafer 50 along the scribe line. In this state, the blade 1 rotating at a high speed is moved downward, and the blade 1 is brought into contact with the cut portion supported from below by the tip 4 of the pusher. Then, with the blade 1 and the pusher 3 fixed in the XY directions in FIG. 1, the stage 5 is moved in the X and Y directions along the scribe line. As a result, the cut portion of the wafer 50 is cut while being supported by the distal end portion 4 of the pusher, and the wafer 50 is divided into a plurality of packages.
[0025]
As described above, according to the dicing apparatus 100 of the present invention, only the periphery of the wafer 50 is fixed to the stage 5. One of the cut portions of the wafer 50 floating from the stage 5 is locally supported by the pusher 3. Then, the blade 1 is brought into contact with the other side of the part to be cut which is locally supported by the pusher 3. In this state, the pusher 3 moves relative to the wafer 50 in conjunction with the blade 1, and a portion to be cut along the scribe line is cut between the pusher 3 and the blade 1.
[0026]
Therefore, even when the wafer 50 is warped, the cut portion of the wafer 50 can be supported without interruption, and the force applied from the blade 1 to the cut portion can be received by the pusher 3. As a result, the wafer 50 can be prevented from fluttering, and the wafer 50 can be diced stably. Therefore, occurrence of chipping can be reduced.
[0027]
In the first embodiment, the blade 1 corresponds to the cutting means of the present invention, and the pusher 3 corresponds to the supporting means of the present invention. The stage 5 corresponds to the fixing means of the present invention, and the dicing sheet 10 corresponds to the sheet member of the present invention. Further, the wafer 50 corresponds to the substrate of the present invention.
In the first embodiment, in the dicing method using the dicing apparatus 100 shown in FIG. 1, the stage 5 is moved along the scribe line while the blade 1 and the pusher 3 are fixed in the XY directions. Although the case where the wafer 50 is moved in the Y direction and the wafer 50 is diced has been described, the dicing method of the wafer 50 is not limited to this. With the stage 5 fixed in the XY directions, the blade 1 and the pusher 3 may be moved coaxially in the XY directions along the scribe line. Also in this case, the same operation and effect as in the case of dicing by moving the stage 5 can be obtained.
(2) Other Embodiments In the first embodiment described above, a case was described in which the distal end portion 4 of the pusher 3 was formed in a rod shape, and the portion for pressing the dicing sheet 10 was formed in an R shape. , But is not limited to this. For example, the portion of the tip 4 that presses the dicing sheet 10 may be a roller having a smooth outer peripheral surface.
[0028]
FIG. 3 is a cross-sectional view illustrating a configuration example of a dicing apparatus 200 according to the second embodiment of the present invention. In the dicing apparatus 200 shown in FIG. 3, portions having the same structure as the dicing apparatus 100 shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted. In the dicing apparatus 200 shown in FIG. 3, the tip 4 'of the pusher is coaxial with the blade 1 and is designed to be movable in the Z direction in FIG. 3 by a motor or the like (not shown). The tip 4 'is designed to be able to rotate on the Z axis, as indicated by the arrow in FIG. Further, the portion of the tip 4 ′ that presses the dicing sheet 10 is a roller having a smooth outer peripheral surface.
[0029]
The roller includes a roller body made of a metal such as stainless steel, and a low-friction fluororesin applied to the roller body. Alternatively, this roller may be composed of only hard rubber or the like. With such a structure, when the stage 5 is moved in the XY direction while the cut portion of the wafer 50 is supported by the outer peripheral surface of the roller, the direction of the tip 4 ′ is adjusted in accordance with the moving direction of the stage 5. Changes and the roller rotates. Therefore, as compared with the dicing apparatus 100, the frictional force generated between the tip portion 4 'of the pusher and the dicing sheet 10 can be reduced, and the wafer 50 can be diced smoothly.
[0030]
In the second embodiment shown in FIG. 3, the rollers provided at the distal end portion 4 'correspond to the rolling elements of the present invention. Further, the rolling element of the present invention is not limited to a roller, and may be, for example, a sphere that is pivotally supported at the tip 4 ′.
Further, the tip portion 4 of the pusher 3 which presses the dicing sheet 10 is rotatable (rotatable) in all directions with respect to the tip portion, for example, like the tip of a commercially available ballpoint pen. A ball is fine.
[0031]
FIG. 4 is a sectional view showing a configuration example of a dicing apparatus 300 according to the third embodiment of the present invention. In the dicing apparatus 300 shown in FIG. 4, portions having the same structure as the dicing apparatus 100 shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted. In the dicing apparatus 200 shown in FIG. 4, the tip portion 4 '' of the pusher is designed so that its mounting position is coaxial with the blade 1 and can be moved in the Z direction in FIG. The portion of the tip 4 ″ that presses the dicing sheet 10 is a ball that is rotatable with respect to the tip 4 ″.
[0032]
This ball is composed of, for example, a ball body made of a metal such as stainless steel and a low friction fluororesin applied to the ball body. Alternatively, this ball may be made of only a fluororesin. With such a structure, when the stage 5 is moved in the XY directions while the cut portion of the wafer 50 is supported by the outer peripheral surface of the ball, the ball freely rotates in accordance with the moving direction of the stage 5. .
[0033]
Therefore, the frictional force generated between the tip 4 ″ of the pusher and the dicing sheet 10 can be further reduced as compared with the dicing devices 100 and 200. In the third embodiment shown in FIG. 4, the ball provided at the tip 4 '' corresponds to the sphere of the present invention.
In the above-described first to third embodiments, the case has been described in which the tip portions 4 and 4 ′, 4 ″ of the pusher are brought into point contact with the dicing sheet 10 to press the dicing sheet 10. A method of pressing the dicing sheet 10 without contacting the tip of the dicing sheet 10 may be adopted. In this case, the repulsive force generated between the (polar) magnetic poles of the same polarity is applied. For example, as the dicing sheet 10, a sheet in which metal powder or the like having positive magnetism is enclosed is used. The pusher 3 has a positive magnetic property. Thereby, a repulsive force is generated between the dicing sheet 10 and the pusher 3, and the dicing sheet 10 is pressed. Even in this case, since the cut portion can be supported without interruption using the pusher 3, the wafer 50 can be prevented from flapping.
[0034]
Further, in this method, since the pusher 3 and the dicing sheet 10 are not in point contact with each other but in non-contact, it is possible to reduce a physical impact given when the wafer 50 is supported. Therefore, this non-contact method is advantageous when dicing a thin wafer.
Further, the dicing sheet 10 may be drawn to the distal end portion 4 of the pusher 3 and may be brought into close contact with the pusher 3 so that no gap is formed between the pusher 3 and the dicing sheet 10. In this case, an attractive force generated between (polar) magnetic poles having different polarities is used. For example, as the dicing sheet 10, a sheet in which positively magnetic metal powder or the like is sealed is used. The pusher 3 has negative magnetism. Also in this case, since the cut portion can be supported without interruption, the wafer 50 can be prevented from fluttering.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration example of a dicing apparatus 100 according to a first embodiment.
FIG. 2 is a plan view showing a configuration example of a stage 5.
FIG. 3 is a sectional view showing a configuration example of a dicing apparatus 200 according to a second embodiment.
FIG. 4 is a sectional view showing a configuration example of a dicing apparatus 300 according to a third embodiment.
FIG. 5 is a sectional view showing a configuration example of a dicing apparatus 90 according to a conventional example.
FIG. 6 is a plan view showing a configuration example of a stage 95 according to a conventional example.
[Explanation of symbols]
Reference Signs List 1 blade, 2 blade holder, 3 pusher, 4, 4 ', 4''tip, 5 stage, 7 wafer mounting position, 8 intake hole, 9 opening, 10 dicing sheet, 50 wafer, 52 ball electrode, 100 , 200, 300 Dicing machine

Claims (5)

In a dicing apparatus that cuts a substrate on which a plurality of circuit elements are integrally formed and separates the circuit elements into individual circuit elements,
Fixing means for fixing the peripheral portion of the substrate,
Supporting means for supporting the cut portion of the substrate to which the peripheral portion is fixed by the fixing means from one side,
A dicing device, comprising: cutting means for cutting, from the other side, a portion to be cut whose one side is supported by the supporting means. A sheet member for holding the substrate is attached to one side of the substrate,
The support means,
The dicing apparatus according to claim 1, wherein the cut portion of the substrate is supported from one side by pressing the sheet member. A portion of the supporting means that presses the sheet member has a rolling element having a smooth outer peripheral surface,
3. The dicing apparatus according to claim 2, wherein the cut portion of the substrate is supported from one side by an outer peripheral surface of the rolling element. A portion of the supporting means that presses the sheet member has a sphere that can rotate in all directions,
3. The dicing apparatus according to claim 2, wherein a cut portion of the substrate is supported from one side by an outer peripheral surface of the sphere. In a dicing method in which a substrate formed by integrally forming a plurality of circuit elements is cut and divided into individual circuit elements,
Affixing a sheet member for holding the substrate to one side of the substrate,
Fixing only the peripheral portion of the substrate to which the sheet member is attached,
A step of pressing the sheet member to support the cut portion of the substrate from one side,
Cutting the site to be cut having one side supported from the other side.

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