JPH0952227A - Cutting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for so cutting a ceramic board that a pattern of a reference of a cutting line is deviated due to sintering strain as to divide it into individual chips without cutting a chip. SOLUTION: The method for cutting a plurality of piezoelectric elements formed on a ceramic board S into individual chips P comprises the steps of recording alignment information in a CPU by aligning a pattern as the reference of all cutting lines L, and calling and referring the information in the case of cutting the lines to be cut.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting method for dividing a plurality of piezoelectric elements or the like formed on a ceramic substrate into individual chips.

[0002]

2. Description of the Related Art Since a ceramic substrate is distorted due to sintering, the position of a pattern (mark), which is a reference of a cutting line attached before sintering, is displaced, and one substrate like a silicon substrate is displaced. The method of aligning the cutting line and performing cutting by index feed is not familiar. The pattern is usually provided on the opposite side of the ceramic substrate, but when the positional deviation of the pattern due to sintering is about 2 mm, it is considered to be within the allowable range, and the center of the deviation is set as a cutting line to perform cutting. In addition, blind cutting was performed by index feed (pitch feed) in parallel with this cutting line as a reference line.

[0003]

However, according to the above-mentioned conventional cutting method, the deviation between the respective patterns is not always within the allowable range, and when the positional deviation occurs beyond the allowable range. However, there is a problem that a chip such as a piezoelectric element is cut and damaged. The present invention has been made to solve such a conventional problem, performs alignment of a pattern serving as a reference for all cutting lines, stores the result as coordinate information in the CPU as coordinate information, and every time cutting is performed. It is an object of the present invention to provide a cutting method in which the CPU executes the alignment information from the CPU and performs cutting while performing precision alignment based on the information.

[0004]

As a means for technically solving the above-mentioned problems, the present invention provides a cutting method for dividing a plurality of piezoelectric elements or the like formed on a ceramic substrate into individual chips. The reference pattern of the cutting line is aligned and the alignment information is stored in the CPU.
The gist of the cutting method is to include at least a step of recording and a step of calling and referring to corresponding alignment information when cutting a line to be cut.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 2 shows an example of a cutting device. For example, a rectangular ceramic substrate S as shown in FIG. 3 is placed on a chuck table T and suction-held, or wax-down is held to move the chuck table T. And the ceramic substrate S is cut by the cutting means C having the rotary blade B after the alignment.

As shown in FIG. 1, the ceramic substrate S has a plurality of chips P such as piezoelectric elements arranged vertically and horizontally at a fixed pitch, and a cutting line L (actually, for dividing each chip P individually). Pattern (mark) 1, 2 ... 1 ', 2' ..., a, b ...
, A ', b' ... are respectively provided on opposite sides of the ceramic substrate. In the illustrated example, the patterns are 1 to 4,
The number is from a to i, but the number is not limited to this.

The pattern is placed at an accurate position before the ceramic substrate S is sintered, but the position of the pattern is displaced due to the distortion of the ceramic substrate S after the sintering. By the means A, all patterns 1, 2, ...
The steps of detecting coordinate values of 1 ', 2' ..., a, b ..., a ', b' ... And recording them as alignment information in the CPU are performed. That is, [“1” (x ₁ , y ₁ ),
“1 ′” (x ₁ ′, y ₁ ′)], [“2” (x ₂ , y
_2), "2 '" _{(x 2', y 2 '} ) ], ... [ "a" (x _a, y _a), "a'" (x _a ', y
_a ′)], [“b” (x _b , y _b ), “b ′” (x
_b ′, y _b ′)], and so on.

In order to cut the ceramic substrate S, for example, when cutting a line connecting the patterns "1" and "1 '", from the CPU, "[1] (x ₁ , y ₁ ),
Performing fine alignment process by "1 '" (x _1', y ₁ ') a step of referring to call the alignment information], i.e. the alignment means A on the basis of the coordinate values.

The above "1" (x ₁ , y ₁ ) and "1 '" (x
Among the coordinates of ₁ ', y ₁ '), it is confirmed whether or not the y coordinate values y and y'are the same. If the same, the rotating blade B
Is positioned at the y-coordinate value and cutting is performed. If they are not the same, correction is performed. That is, Δθ is calculated by tan ⁻¹ Δθ = (y ₁ ′ −y) / (x ₁ ′ −x ₁ ), and the chuck table T is rotated to obtain Δ.
The θ correction is performed and the y coordinate value is also corrected. For example, if the coordinates of the pattern “1” are polar coordinates (r, θ) around the center of rotation of the chuck table T, the correction value Δy
Becomes Δy = r [sin (θ + Δθ) −sin θ], and the rotary blade B should be positioned at the coordinate value of (y ₁ + Δy). Thereafter, this is repeated.

In this manner, the CPU calls the alignment information for each cutting line in the X-axis direction, and the cutting is performed while performing the precise alignment based on the alignment information. The chip is not cut if it is cut along the cutting line that connects the patterns. To cut along the Y-axis direction, the chuck table can be rotated 90 degrees and the cutting can be performed in the same manner as in the case of the X-axis direction.

[0011]

As described above, according to the present invention,
Even if the ceramic substrate is misaligned due to the distortion of sintering due to the distortion of the cutting line, the pattern coordinate values stored in advance as alignment information are called from the CPU for each cutting line, and cutting is performed while performing precision alignment. Since this is a method, the chip such as the piezoelectric element is not cut, and the effect of preventing damage to the chip is obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 is a perspective view showing an example of a cutting device.

FIG. 3 is a schematic perspective view showing a cut state of a ceramic substrate.

[Explanation of symbols]

 A ... Alignment means B ... Rotating blade C ... Cutting means L ... Cutting line P ... Chip S ... Ceramic substrate T ... Chuck table

Claims (1)

[Claims] 1. A cutting method for dividing a plurality of piezoelectric elements or the like formed on a ceramic substrate into individual chips,
A step of aligning a reference pattern of all cutting lines and recording the alignment information in the CPU;
And a step of calling and referring to corresponding alignment information when cutting a line to be cut.