JP2003191150A - Method for detecting unbalance of rotation blade and detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for detecting unbalance of a rotary blade and a detection device capable of automatically detecting the unbalance of the rotation blade and rapidly feeding back the result. <P>SOLUTION: In the method for detecting an unbalance of a rotation blade in a multi-blade type dicing device 10, a plurality of sheets of rotation blades 12 is fixed to the same shaft 14 at an interval and a dicing is carried out by a plurality of sheets of rotation blades 12. Of the rotation blades 12, a position detection means 16 at a tip end of the rotation blade is disposed near at a tip of at least one sheet of blade and a detection of the unbalance of the rotation blade 12 is carried out by the position detection means. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dicing apparatus for grooving a work in semiconductor manufacturing or the like, and more particularly, it is of a multi-blade type in which a plurality of rotating blades are fixed to the same shaft at intervals. The present invention relates to an unbalance detection method and a detection device in a dicing device.

[0002]

2. Description of the Related Art In recent years, a dicing device for grooving a work has been widely used in semiconductor manufacturing and the like. Among these, a multi-blade type dicing device in which a plurality of rotating blades are fixed to the same shaft at intervals is being introduced into the manufacturing process because high throughput can be obtained.

In particular, CSP (Chip Size Pa)
Cage) is often square in shape, and the error between pitches is less severe than that of silicon wafers.
The application of a multi-blade type dicing device is expected.

In the above apparatus, the rotary blade is a donut disk-shaped metal bond diamond grindstone (diamond wheel), for example, a thickness of about 0.1 mm,
The outer circumference is generally 56 mm or 76 mm. The pitch interval between the rotating blades is usually 5 to 18 m.
The range of m is adopted.

The method of providing the pitch intervals between the rotating blades is generally based on a structure in which the rotating blades and spacers are alternately fixed to the same shaft.

[0006]

However, variations in the concentricity of the rotary blade and the spacer, backlash between the inner diameter of the rotary blade and the spacer and the shaft (or flange), variations in the accuracy of attachment to the shaft (or flange), etc. In many cases, the tips of the rotating blades are not aligned among the plurality of rotating blades. Further, even if the tips of the rotating blades are aligned among the plurality of rotating blades, the dynamic balance may not be balanced when the rotating blades are rotated.

In such a case, the rotational shake of the rotating blade during rotation becomes large, causing problems such as damage to the work and damage to the rotating blade. In an extreme case, it is feared that the rotary shaft composed of the air bearing means may be destroyed.

This phenomenon is a problem that the conventional single-blade type dicing device does not have, and is a problem that must be overcome when using a multi-blade type dicing device. However, until now there has been no effective solution to this.

The present invention has been made in view of such circumstances, and in a multi-blade type dicing device, an imbalance of a rotating blade can be automatically detected, and the result can be quickly fed back. An object is to provide an unbalance detection method and a detection device.

[0010]

In order to achieve the above object, the present invention is a multi-blade in which a plurality of rotary blades are fixed to the same shaft at intervals and dicing is performed by the plurality of rotary blades. A method for detecting an unbalance of a rotating blade in a dicing device of the type, wherein a position detecting means for the tip of the rotating blade is arranged in the vicinity of at least one blade of the rotating blade, and the rotating blade is unbalanced by the position detecting means. The feature is that balance is detected.

According to the present invention, since the unbalance of the rotating blade can be detected during the operation of the apparatus by the position detecting means at the tip of the rotating blade arranged near the blade edge of the rotating blade, the result can be fed back quickly. It is possible to promptly deal with troubles such as expected work damage and rotary blade damage. As a result, it is possible to improve the operating rate and the yield.

In the present invention, the position detecting means at the tip of the rotary blade has a light projecting means and a light receiving means, and the light beam between the light projecting means and the light receiving means is blocked by the rotary blade to thereby rotate the rotary blade. It is preferable to detect the position of the tip. This type of position detecting means is excellent in high-speed response and detection accuracy and is suitable for proximity sensing in such a dicing device.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a rotating blade unbalance detecting method and detecting apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a conceptual diagram illustrating an embodiment of a rotating blade unbalance detection method and a detection device according to the present invention, and FIG. 2 is an enlarged side sectional view of the same part.

The dicing device 10 is mainly composed of a work supporting side 30 and a rotary blade supporting side 20.

A table 32 for supporting the work W is provided on the work supporting side 30. The work W is fixed to the upper surface of the table 32 via an adhesive sheet 34.
In FIG. 1, the table 32 can be moved in the X direction (horizontal direction) by a moving device (not shown).

On the rotary blade supporting side 20, a motor 24 is provided to the apparatus main body (not shown) via a motor supporting portion 26.
Is attached. In FIG. 1, the motor can be moved in the Z direction (vertical direction) and the Y direction (direction perpendicular to the paper surface) by a moving device (not shown).

A flange 2 is attached to the tip of the shaft 14 of the motor 24.
2 is attached, and a plurality of rotary blades 12, 12, ... Can be attached to the outer periphery of the flange 22.
In FIG. 2, the rotary blades 12 and the spacers 13 are alternately attached to the flanges 22, so that the plurality of rotary blades 12, 12, ...
Will be fixed at a distance.

The rotary blade 12 is a donut disk-shaped metal bond diamond grindstone (diamond wheel).
So, for example, the thickness is around 0.1mm and the outer circumference is 56mm.
Alternatively, a 76 mm one can be used. Depending on the case, a resin-bonded diamond grindstone or an electrodeposition grindstone in which diamond abrasive grains are formed by electrodeposition on the outer peripheral portion of a nickel donut disk-shaped member can be used.

In the configuration of FIG. 2, the rotary blades 12, 12
The pitch interval between them is 6 mm. When processing a CSP, this pitch interval is usually in the range of 5 to 18 mm.

On the rotary blade supporting side 20, a position detecting means 16 for the tip of the rotary blade 12 is arranged near the cutting edge of the rotary blade 12. The position detecting means 16 at the tip of the rotary blade is fixed to the apparatus main body (not shown) through position adjusting means. That is, the position of the position detecting means 16 at the tip of the rotary blade can be adjusted to correspond to the outer diameter size of the rotary blade 12 to be measured.

The position detecting means 16 at the tip of the rotary blade is
A prism 62 on the light emitting means side and a prism 64 on the light receiving means side attached to the tip of the position detecting means main body 60, an optical fiber 66 on the light emitting means side connected to the back surface of the prism 62, and a light receiving connected to the back surface of the prism 64. It is composed of an optical fiber 68 on the means side.

In the optical fiber 66 on the side of the light projecting means, a laser light 70 is emitted from a laser light source which is a light projecting means (not shown).
Is emitted, and the emitted laser light 70 is reflected by the prism 62.
Incident on the prism 62, is reflected at a right angle on the inclined surface of the prism 62, is incident on the prism 64, is reflected at a right angle on the inclined surface of the prism 64, is incident on the optical fiber 68, and is detected by an optical sensor which is a light receiving means (not shown). .

As shown, prism 62 and prism 6
The tip portion of 4 is arranged so as to sandwich the tip of the rotary blade 12, and the position of the tip of the rotary blade can be detected by blocking the light flux.

The laser light 70 used for detecting the position of the tip of the rotary blade has a better straightness than ordinary light and has less divergence of the light flux, but still has a light flux of a predetermined width.
Therefore, it is preferable to provide a collimator or the like on the light projecting means side so that the detection accuracy is as high as possible, and adjust so that the width of the light flux is minimized near the tip of the rotary blade 12.

The details of the method of detecting the imbalance of the rotary blade 12 by the position detecting means 16 at the tip of the rotary blade will be described below with reference to FIGS. 3 and 4.
The configuration will be described in detail.

As another component of the dicing apparatus 10, in FIG. 1, a grinding fluid injection nozzle 28 is arranged near the rotary blade 12, and the rotary blade 12 is provided.
And the work W is cooled, and the grindability is maintained. Similarly, cooling water jet nozzles 29 are arranged near both sides of the rotary blade 12 to cool the rotary blade 12.

3 and 4 are conceptual diagrams for explaining another embodiment of the rotating blade unbalance detecting method and detecting apparatus according to the present invention. In each figure,
Members that are the same as or similar to those in FIG. 2 are given the same numbers and their explanations are omitted. Further, for convenience of explanation, only one rotary blade 12 is shown.

FIG. 3 is a conceptual diagram for explaining an embodiment of an unbalance detecting device for a rotary blade according to the present invention. The position detecting means 16 at the tip of the rotary blade is an X table 51.
It has a pair of optical systems 82 incorporated in an inspection table 80 provided above. One optical system of the pair of optical systems has a lens system 84 and a prism 86, and the other optical system has a lens system 88 and a prism 90, and the prism 86 and the prism 90 are arranged to face each other. .

One optical system is a glass fiber 92.
At the light projecting means 94, the other optical system is the glass fiber 9
It is connected to the light receiving means 98 at 6. A light emitting diode is used as the light projecting means 94, and a photodiode is used as the light receiving means 98.

On the other hand, the rotary blade 12 attached to the tip of the shaft 14 with a built-in high-frequency motor has a Z-direction drive means 55.
Is driven in the Z direction, and in the Y direction (perpendicular to the paper surface) by the Y direction driving means (not shown). The Z direction drive means 55 performs closed loop control based on the position information from the Z direction movement amount detection means 56, and the positioning accuracy is 2 μm.
Within / 5 mm (maximum rotating blade 12 is 5 mm in Z direction)
Positioning is performed with high accuracy (positioning error within 2 μm when moved to).

Further, the control means 43 for controlling the drive of the rotary blade 12, the arithmetic means 41 for arithmetically processing the amount of received light obtained in synchronization with the rotation of the blade 54, the storage means 44, and the deformation state of the blade 54 are displayed. Display means 42
A controller 40 including the above is provided.

The light emitted from the light emitting diode of the light projecting means 94 enters the lens system 84 through the glass fiber 92, is refracted, is reflected in the horizontal direction by the prism 86, and has a diameter between the prism 86 and the prism 90. It is condensed into a luminous flux of about 0.5 mm. The condensed light is reflected by the prism 90, refracted by the lens system 88, and enters one end of the glass fiber 96. The light incident on one end of the glass fiber 96 illuminates the photodiode of the light receiving means 98, and the signal photoelectrically converted by the photodiode is input to the controller 40.

When detecting the position of the tip of the rotary blade 12, first, the rotary blade 12 is positioned right above the converging point between the prism 86 and the prism 90 by the Y direction drive means (not shown), and is driven in the Z direction. The light flux that has been moved downward and condensed by the means 55 is partially blocked, and the amount of received light is measured.

Next, details of detection of the tip position of the rotary blade 12 will be described. FIG. 4 shows the Z of the rotary blade 12.
It is a graph explaining a direction reference position calculation method. Figure 4
(A) shows the relationship between the Z direction position of the rotary blade 12 and the amount of received light, with the horizontal axis representing the descending amount of the rotary blade 12 and the amount of received light in the vertical axis.

4 (b) and 4 (c), the horizontal axis represents the rotation angle of the rotary blade 12 and the vertical axis represents the amount of received light, and the amount of received light with respect to the rotational angle of the rotary blade 12 at each of Z ₁ and Z ₂ positions. It shows a curve showing the periodic fluctuation of.

As shown in FIG. 4, first, at the position where the rotary blade 12 does not block the converged light beam, the light receiving means 98 is provided.
The received light amount data V ₀ detected by is stored. Next, the Z direction driving means 55 positions the tip of the rotating rotary blade 12 at an arbitrary position Z ₁ near the optical axis of the light condensed by the optical system. At this position, in synchronization with the rotation of the rotary blade 12, the received light amount data of a plurality of points per cycle is read and stored in the storage means 44.

Since the photodiode used in the light receiving means has a high response speed within 10 μs, even if the rotating speed of the rotating blade 12 is rotated at a speed of, for example, 60,000 rpm, more than 100 photodiodes per one rotation. Data on the amount of received light can be collected.

Since the tip of the rotary blade 12 is deformed with respect to the axis of the rotary shaft due to eccentricity, the amount V of light received with respect to the rotation angle θ becomes a sine curve as shown in FIG. 4 (b). The value V _{1 at the} bottom of the sine curve is the amount of light received when the light beam is blocked at the tip of the rotary blade 12 at the Z ₁ position. After storing the received light amount V ₁ in the storage means 44, the tip of the rotary blade 12 is then positioned at another arbitrary position Z ₂ near the optical axis.

Even at this position, in synchronization with the rotation of the rotary blade 12, the received light amount data of a plurality of points per cycle is read and stored in the storage means 44 to obtain the minimum received light amount V ₂ . From the data (Z ₁ , V ₁ ) and (Z ₂ , V ₂ ) at these two points, the calculation means 41 of the controller 40 determines the relationship between the amount of received light and the position of the rotary blade 12 in the Z direction as a function.
In the case of the present embodiment, since the received light amount data is obtained at two positions near the optical axis, the function is a linear function and the graph is a straight line between two points.

Next, using this function, the amount of received light V _0/2
The Z direction position Z ₀ of the rotary blade 12 corresponding to is calculated by the calculation means 41. Z ₀ calculated here is Z
As the directional reference position, the subsequent height direction control of the rotary blade 12 is performed.

The reason why the received light amount data is obtained at a position near the optical axis is that the detected light amount is good in the vicinity of the optical axis because the received light amount changes almost linearly with respect to the descending amount of the rotary blade 12.

When applied to an actual processing device, FIG.
As shown in, the relative distance K between the Z-direction reference position Z ₀ and the upper surface position of the work machining table 52 (corresponding to the table 32 in FIG. 1) is obtained, and the value of this K is used as an offset value for height. Control the direction. When obtaining the upper surface position of the work processing table 52 described above, the rotary blade 12 and the work processing table 52 are respectively energized, and the rotary blade 12 is gradually lowered to be brought into contact with the top surface of the work processing table 52 to establish conduction. Read the instantaneous position. Once this offset value K is stored, it can be applied even if the outer diameter of the rotating blade 12 is different by replacing the rotating blade 12.

The work processing table 52 is provided on the same side as the optical system 82, that is, on the X table 51 for convenience of explaining the principle of detecting the tip position of the rotary blade 12, but in reality, the optical system 82 is used. It is provided opposite to the opposite side.

In the description of the present embodiment, the position of the rotary blade 12 for detecting the amount of received light is described as _two positions of arbitrary positions Z ₁ and Z _{2 in} the vicinity of the optical axis, but at three or more positions. It doesn't matter.

In addition, as described above, the position detecting means 16 at the tip of the rotary blade has a light projecting means and a light receiving means, and the light flux between the light projecting means and the light receiving means is the rotary blade 12. It is preferable to use a detecting means for detecting the position of the tip of the rotary blade 12 by being blocked, but other detecting means (sensor) such as an eddy current type proximity sensor, a laser type distance sensor, or a capacitance type sensor. Various sensors such as a proximity sensor can also be used.

Next, the imbalance detection of the rotary blade 12 using the rotary blade unbalance detection detection device in the dicing device 10 having the configuration of FIGS. 1 and 2 will be described. The rotating blade 12 was a metal bond diamond grindstone having a thickness of 0.1 mm and an outer circumference of 56 mm, and the rotation speed during operation of the apparatus was 30,000 rpm. The position detecting means 16 at the tip of the rotary blade is arranged in the vicinity of the cutting edge of one rotary blade 12.

Four rotary blades 12 were attached, the apparatus was operated in the state where the work W was not processed, and the operation of the rotary blade unbalance detection apparatus was confirmed. As a result, the tip of the rotary blade 12 on which the position detecting means 16 for the tip of the rotary blade is arranged has a specified allowable value (for example, 0.05 mm).
Unbalance was detected when the blur was more than the above.

The apparatus was operated with the work W attached, and the operation of the rotating blade unbalance detection apparatus was confirmed. At this time, when the tip of the rotary blade 12 on which the position detecting means 16 for the tip of the rotary blade is arranged has a blur greater than a specified allowable value (for example, about 0.05 mm), the controller 40 (hereinafter, referred to as FIG. Display means 4)
A warning is displayed on the display 2, and the control means 43 of the controller 40 is programmed to stop the operation of the apparatus. As a result, it was confirmed that normal operation could be performed.

[0049]

As described above, according to the present invention,
In a multi-blade type dicing device, by arranging a position detecting means of the tip of the rotating blade in the vicinity of the blade edge of the rotating blade and detecting the unbalance of the rotating blade by the position detecting means, the rotating blade during operation of the device. The unbalance can be detected, the result can be quickly fed back, and troubles such as expected damage to the work and damage to the rotating blade can be quickly dealt with. As a result, it is possible to improve the operating rate and the yield.

[Brief description of drawings]

FIG. 1 is a conceptual diagram illustrating an embodiment of a rotary blade unbalance detection device according to the present invention.

FIG. 2 is an enlarged side sectional view of the same main part.

FIG. 3 is a conceptual diagram illustrating another embodiment of an unbalance detecting device for a rotating blade according to the present invention.

FIG. 4 is a conceptual diagram illustrating a method for calculating a Z-direction reference position of a rotating blade.

[Explanation of symbols]

10 ... Dicing device, 12 ... Rotating blade, 14 ...
Shaft, 16 ... Rotating blade tip position detecting means, 20 ... Blade support side, 22 ... Flange, 24 ... Motor, 26 ...
Motor support part, 30 ... Work support side, 32 ... Table,
34 ... Adhesive sheet, W ... Work

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinobu Imai             9-7 Shimorenjaku, Mitaka City, Tokyo Stocks             Company Tokyo Seimitsu F term (reference) 3C029 AA24 AA40                 3C034 AA19 BB63 BB93 CA24 CB13                       CB14 DD18

Claims (4)

[Claims] 1. A method for detecting an unbalance of rotating blades in a multi-blade type dicing device, wherein a plurality of rotating blades are fixed to the same shaft at intervals and dicing is performed by the plurality of rotating blades. Among the rotating blades, at least one blade of the rotating blade is provided with a position detecting means at the tip of the rotating blade, and the position detecting means detects the unbalance of the rotating blade. Method. 2. The position detecting means at the tip of the rotary blade comprises:
The unbalanced rotary blade according to claim 1, further comprising: a light projecting means and a light receiving means, wherein the position of the tip of the rotary blade is detected by blocking a light beam between the light projecting means and the light receiving means by the rotary blade. Detection method. 3. An unbalance detecting device for a rotating blade in a multi-blade type dicing device in which a plurality of rotating blades are fixed to the same shaft at intervals with dicing being performed by the plurality of rotating blades. Of the rotating blades, at least one blade of the rotating blade is provided with a position detecting means at the tip of the rotating blade and the position detecting means detects the unbalance of the rotating blade. Unbalance detection device. 4. The position detecting means at the tip of the rotary blade comprises:
4. The rotary blade antenna according to claim 3, further comprising a light projecting means and a light receiving means, wherein the position of the tip of the rotary blade is detected by blocking the light flux between the light projecting means and the light receiving means by the rotary blade. Balance detection device.