JP2012040708A - Dividing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dividing method capable of cutting and dividing a ceramic substrate which is subjected to a hole-boring process and then is sintered, the dividing method cutting the sintered ceramic substrate along cutting-scheduled planes which connect between center axes of the bore holes with a high degree of accuracy.SOLUTION: The dividing method includes: a step of forming a protective film 10 on a surface of the ceramic substrate 1 subjected to the hole-boring process and the sintering process; a subsequent step of imaging the surface side with an imaging unit 30 to detect a coordinate position of each of the holes 3 and store the coordinate positions as hole position information; and a further step of determining and storing the center coordinates 3A of the holes 3 based on the hole position information. The dividing method further includes: a step of calculating a linear function which connects center coordinates 3A of the holes 3 adjoining each other, with a straight line; and a step of performing the irradiation with a laser beam LB so as to successively connects the center coordinates 3A of the holes 3 adjoining each other, based on the linear function to perform ablation working, thereby dividing the ceramic substrate 1 into chips 7.

Description

  The present invention relates to a method of dividing a ceramic substrate or the like into a plurality of pieces, and in particular, to connect a ceramic substrate that has been sintered after a plurality of holes have been drilled along a division line. The present invention relates to a dividing method of dividing along a planned dividing line.

  In the field of manufacturing electronic components such as semiconductor devices, when dicing a workpiece such as a thin plate substrate to obtain a large number of chips, a cutting process is adopted in which a cutting blade is cut along the division lines formed on the workpiece. Has been. In a normal semiconductor wafer, an alignment process is performed to align the planned dividing line to be cut with the cutting blade, and then the aligned divided scheduled line is cut, and thereafter, cutting is performed at intervals of the planned dividing line. Cutting is performed while indexing and feeding the blade and selecting the division line to be cut. That is, the alignment is performed only on the planned division line to be cut first, and thereafter, dicing is performed based on data such as the interval of the predetermined division line obtained in advance. Therefore, cutting is performed on the assumption that all the division lines are formed in parallel with high accuracy (see Patent Document 1).

JP-A-6-69319

  Thus, for example, a workpiece such as a ceramic substrate may be required to be diced so that the corners of the chip have a notch shape for the convenience of assembly in a later process. In order to form notches in the corners of the chip, before the workpiece is sintered, a hole is drilled at the location corresponding to the corner of the chip on the line to be divided, and then divided after sintering. This is done by cutting the workpiece along the planned line.

  However, since the ceramic substrate is distorted by sintering, there is a disadvantage that the position of the hole after sintering shifts from the position before sintering. For this reason, even if the workpiece is cut along the planned division line after alignment is performed as in the past, the actual cutting line does not connect the holes with high precision, and the chip is accurately aligned. There was a problem that notches could not be formed in the corners.

  The present invention has been made in view of the above circumstances, and the main technical problem thereof is that the center of the hole is highly accurate with respect to the ceramic substrate that has been sintered after being subjected to drilling. An object of the present invention is to provide a dividing method that can be cut and divided so as to be connected.

  The dividing method of the present invention is a dividing method of dividing a ceramic substrate, which has been sintered after being subjected to a plurality of perforations along the planned dividing line, along the planned dividing line so as to connect the holes. A step of forming a protective film on the surface to be processed of the ceramic substrate, and detecting the coordinate position of the holes by sequentially positioning and imaging the holes within the imaging range of the imaging means, and storing them as hole position information A step of calculating and storing the center coordinates of the hole based on the hole position information, and calculating a linear function connecting the adjacent center coordinates by a straight line, and along the division planned line based on the linear function And ablating by irradiating a laser beam along the planned dividing line so as to successively connect adjacent central coordinates of the holes arranged side by side.

  The present invention obtains center coordinates for each hole of a ceramic substrate that has been drilled and sintered, and cuts and divides the ceramic substrate by ablation processing by laser beam irradiation so as to connect these center coordinates. is there. According to the present invention, since the cutting is performed based on the center coordinates of the hole after sintering, the center of the hole can be cut with high accuracy, and the tip corner obtained after the division can be cut conventionally. A notch with a uniform shape is also formed.

  ADVANTAGE OF THE INVENTION According to this invention, the division | segmentation method which can be cut | disconnected and divided | segmented so that between the centers of a hole may be provided with high precision is provided with respect to the ceramic board | substrate sintered after the drilling process was given. There is an effect such as.

It is a top view of the ceramic substrate by which the punching process divided | segmented into many chips | tips with the division | segmentation method which concerns on one Embodiment of this invention. It is a top view of the chip | tip obtained from a ceramic substrate, Comprising: (a) The chip | tip of the shape which is going to be obtained, (b) The chip | tip conventionally obtained. It is an enlarged view of the III part of FIG. It is a partial cross section side view which shows the state in which the protective film was formed in the surface (processed surface) of a ceramic substrate. It is a side view which shows the process of imaging the surface of a ceramic substrate with an imaging means. It is a figure which shows the actual division line which connects the center coordinate of an adjacent hole. It is a figure which shows the center coordinate of the hole of a ceramic substrate. It is a side view which shows the process of dividing | segmenting a ceramic substrate by the ablation process by laser beam irradiation. It is a top view of the chip | tip obtained with the division | segmentation method of one Embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a square ceramic substrate that is divided into a large number of chips by applying the dividing method according to an embodiment. The ceramic substrate 1 is obtained by first performing a drilling process for forming a large number of holes 3 at equal intervals along a grid-like division planned line 2 and thereafter sintering. The ceramic substrate 1 is cut and divided along the division line 2 and divided into chips 5 shown in FIG. The chip 5 shown in FIG. 1 has an ideal shape to be obtained from the ceramic substrate 1 by forming quarter-arc cutouts 6 at the corners of a square by holes 3.

  However, since the ceramic substrate 1 is distorted by the sintering after drilling, the holes 3 may be displaced from the original division line 2 as shown in FIG. Accordingly, the chip 5 obtained by dividing along the planned dividing line 2 does not actually have a uniform quarter arc shape with the corner notches 6 as shown in FIG. There are variations.

  Therefore, the division method according to one embodiment is a method in which the corner notches 6 of all the chips 5 obtained by the division are formed into a uniform 1/4 arc shape as compared with the prior art. The procedure will be described below.

  First, as shown in FIG. 4, a protective film 10 is formed on the surface of the ceramic substrate 1 (the surface to be processed, the upper surface in FIG. 4). The protective film 10 can be formed, for example, by applying a liquid water-soluble resin to the surface of the ceramic substrate 1. Examples of the water-soluble resin include water-soluble resists such as polyvinyl alcohol (PVA), polyethylene glycol (PEG), and polyethylene oxide (PEO). In addition, as a method for applying the resin, a spin coating method or the like in which the resin dripped at the rotation center of the surface of the rotated ceramic substrate 1 is spread over the entire surface by centrifugal force is used.

  Next, as shown in FIG. 5, the ceramic substrate 1 is horizontally held on a suitable holding table 20 with the protective film 10 side facing up. Then, the imaging means 30 and the holding table 20 arranged above the holding table 20 are relatively moved in the horizontal direction so that the holes 3 are sequentially positioned within the imaging range of the imaging means 30 and all the holes 3 are imaged. The protective film 10 has a thickness of, for example, about several hundred μm to several μm. Even when the protective film 10 covers the hole 3, the hole 3 can be imaged from the surface side. At this time, the coordinate position of the hole 3 is detected at any time for each imaged hole 3, and the coordinate position is stored in a storage means (not shown) as hole position information. FIG. 6 shows an example of the imaging range of the imaging means 30. Each hole 3 is imaged in this way, and the coordinate position is detected.

  Next, based on the obtained hole position information, the center coordinates (indicated by 3A in FIG. 7) of all the holes 3 are obtained and stored in the storage means.

  Next, a linear function that connects the central coordinates 3 </ b> A of the adjacent holes 3 with a straight line is calculated for all the adjacent holes 3. Then, based on these obtained linear functions, the adjacent center coordinates 3A of the aligned holes 3 are connected one after another, and the holes 3 are cut by laser processing.

  In this case, as shown in FIG. 8, the laser beam irradiation means 40 and the holding table 20 disposed above the holding table 20 are moved relative to each other in the horizontal direction, and the laser substrate irradiation means 40 focuses on the ceramic substrate 1. Then, the ceramic substrate 1 is cut by an ablation process in which the components of the ceramic substrate 1 are melted and evaporated to be removed by irradiation with the laser beam LB. A broken line in FIG. 6 is a scanning line of the laser beam LB irradiated so as to connect the center coordinates 3A of the hole 3, which is an actual dividing line.

  When ablation processing is performed, debris may be generated in which evaporated components are scattered and solidified. However, since the protective film 10 is formed on the surface of the ceramic substrate 1 in this embodiment, the generated debris adheres to the surface of the protective film 10. For this reason, contamination of the ceramic substrate 1 is prevented, and as a result, the quality of the chip is maintained.

  As described above, the ablation processing by the laser beam LB is sequentially performed between the holes 3 and 3, thereby dividing the ceramic substrate 1 into a large number of chips 7 (see FIG. 9). According to the dividing method of the present embodiment, the center coordinates 3A of the holes 3 whose positions are shifted after the ceramic substrate 1 is sintered are obtained, and the center coordinates 3A are linearly connected to each other. The laser beam LB is irradiated at intervals and cut. For this reason, it is possible to cut between the centers of the adjacent holes 3 with high accuracy. As a result, as shown in FIG. 9, the corner of the chip 7 obtained after the division has a 1/4 arc shape which is more uniform than the conventional one. A notch 8 is formed.

DESCRIPTION OF SYMBOLS 1 ... Ceramic substrate 2 ... Planned division line 3 ... Hole 3A ... Center coordinate 10 of hole ... Protective film 30 ... Imaging means LB ... Laser beam

Claims (1)

A dividing method of dividing a ceramic substrate 1 that has been sintered after being subjected to a plurality of drilling processes along a division line, along the division line so as to connect the holes,
Forming a protective film on the work surface of the ceramic substrate;
Detecting the coordinate position of the hole by sequentially positioning and imaging the hole within the imaging range of the imaging means, and storing it as hole position information;
Obtaining and storing center coordinates of the hole based on the hole position information;
A linear function that connects adjacent central coordinates with a straight line is calculated, and a laser is generated along the planned division line so that adjacent central coordinates of the holes arranged along the planned division line are connected one after another based on the linear function. A process of ablating by irradiating a beam;
A dividing method characterized by including:

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