JP7656508B2 - Machining method and cutting device - Google Patents

Description

The present invention relates to a processing method and cutting device that cuts a package substrate in steps with two blades of different thicknesses to form a chip (package) with a stepped cutout on the side.

In recent years, as electrical devices have become smaller, package sizes have also become smaller, resulting in smaller electrode areas on package substrates. As a result, packages with wettable flanks are being widely adopted to strengthen the bond with the mounting substrate and to improve the visibility of the bond.

A wettable flank package is formed by half-cutting the package substrate along the planned dividing line with a blade to expose the electrodes partway through their thickness on the cut surface, plating the electrodes, and then fully cutting them with a blade narrower than the half-cut groove (see, for example, Patent Document 1).

Wettable flank packages improve the wettability of the solder by cutting notches into the side of the electrode and plating it. Furthermore, by forming stepped notches on the side, the solder supplied to the notch during mounting forms a raised shape called a fillet, resembling the foot of Mount Fuji, allowing the solder joint to be visually confirmed from the top and sides, making it possible to carry out visual inspections using a camera.

JP 2020-161615 A

However, as the cutting blade wears, an R-shape forms at the tip, so if cutting is continued without changing the cutting depth when an R-shape has formed at the tip of the half-cut blade, the depth of the notch formed on the side of the chip (package) will change.

If the depth of the notch changes, the fillet, which is the solder connection that is exposed on the side of the package during mounting, may not be formed at a sufficient height from the mounting board, which could reduce the reliability of the inspection or lead to poor connections.

Therefore, the object of the present invention is to provide a processing method and cutting device that can suppress deterioration of chip reliability and connection failure.

In order to solve the above-mentioned problems and achieve the object, the processing method of the present invention is a processing method for forming a chip with a stepped notch on the side by half-cutting a package substrate on which a plurality of intersecting planned division lines are set with a first blade and then full-cutting with a second blade having a blade thickness thinner than the first blade, and includes a half-cut step in which the first blade is cut into the package substrate and the package substrate is cut along the planned division lines with the first blade to form a first cut groove and an uncut portion below the first cut groove, a full-cut step in which, after the half-cut step, the second blade, which is thinner than the first blade, cuts the uncut portion along the first cut groove, and a tip shape confirmation step in which the tip shape of the first blade is confirmed, and in the half-cut step, the first blade is cut into the package substrate to a cutting depth that makes the depth of the notch a predetermined depth based on the tip shape of the first blade confirmed in the tip shape confirmation step and the blade thickness of the second blade.

In the processing method, the tip shape confirmation step may involve forming a cutting mark on the upper surface of the package substrate with the first blade, and confirming the tip shape of the first blade based on the cutting mark.

The processing method may also include a flattening step for correcting and flattening the tip of the first blade at a predetermined timing.

The cutting device of the present invention is a cutting device that forms a chip with a stepped cutout portion on the side by half-cutting a package substrate on which a plurality of intersecting planned division lines are set with a first blade and then fully cutting with a second blade having a blade thickness thinner than the first blade, and is characterized in that it includes a table that holds the package substrate, a first cutting unit having a first blade that cuts the package substrate along the planned division lines to form a first cutting groove and forms an uncut portion below the first cutting groove, a second cutting unit having a second blade that is thinner than the first blade and cuts the uncut portion along the first cutting groove, an imaging unit that images the cutting marks formed by cutting the first blade into the cutting object, and a control unit that controls each component, and the control unit includes an estimation unit that estimates the tip shape of the first blade based on an image captured by the imaging unit, and a calculation unit that calculates the cutting depth of the first blade so that the depth of the notch is a predetermined depth based on the tip shape of the first blade and the blade thickness of the second blade estimated by the estimation unit.

The present invention has the effect of suppressing deterioration of chip reliability and poor connections.

FIG. 1 is a perspective view illustrating an example of the configuration of a cutting device according to a first embodiment. FIG. 2 is a plan view of a package substrate to be processed by the processing method and cutting device according to the first embodiment. FIG. 3 is a side view of the package substrate shown in FIG. FIG. 4 is a plan view of the back surface side of the package substrate shown in FIG. FIG. 5 is a perspective view of a packaged chip obtained by dividing the package substrate shown in FIG. FIG. 6 is a front view showing the first cutting unit and the second cutting unit of the cutting device shown in FIG. FIG. 7 is a flowchart showing the flow of the processing method according to the first embodiment. FIG. 8 is a cross-sectional view that typically shows a half-cut step of the processing method shown in FIG. FIG. 9 is a cross-sectional view that typically shows a full-cut step of the processing method shown in FIG. FIG. 10 is a cross-sectional view that typically shows a state before the first blade of the cutting device shown in FIG. 1 is worn down. FIG. 11 is a cross-sectional view showing a schematic state in which the first blade shown in FIG. 10 is worn. FIG. 12 is a cross-sectional view showing a state in which the first blade shown in FIG. 11 has been further worn. 13 is a side view, partially in cross section, showing a state in which the cutting edge of the first blade is cut into the peripheral excess region of the base substrate of the package substrate in the tip shape confirmation step of the processing method shown in FIG. FIG. 14 is a plan view of the peripheral excess area of the base substrate of the package substrate on which cutting marks are formed in the tip shape confirmation step of the processing method shown in FIG. FIG. 15 is a diagram showing an image obtained by imaging the cutting trace by the imaging unit in the tip shape confirmation step of the processing method shown in FIG. 16 is a diagram showing an image of the tip of the cutting edge of the first blade generated by reducing the length of the image shown in FIG. 15 in the tip shape confirmation step of the processing method shown in FIG. FIG. 17 is a cross-sectional view of the tip of the cutting edge of the first blade on which the cutting mark shown in FIG. 14 is formed. FIG. 18 is a vertical cross-sectional view parallel to the longitudinal direction of the cutting mark shown in FIG. FIG. 19 is a cross-sectional view that typically shows the cutting depth and the like calculated in the tip shape confirmation step of the processing method shown in FIG. Figure 20 is a side view, partially in cross section, showing a schematic diagram of the cutting edge of the first blade cutting into the peripheral excess region of the base substrate of the package substrate in the tip shape confirmation step of the processing method according to a modified example of embodiment 1. FIG. 21 is a plan view of a peripheral excess region of a base substrate of a package substrate on which cutting marks are formed in a tip shape confirmation step of a processing method according to a modified example of the first embodiment.

A detailed description of the form (embodiment) for carrying out the present invention will be given with reference to the drawings. The present invention is not limited to the contents described in the following embodiment 1. Furthermore, the components described below include those that a person skilled in the art can easily imagine and those that are substantially the same. Furthermore, the configurations described below can be appropriately combined. Furthermore, various omissions, substitutions, or modifications of the configuration can be made without departing from the gist of the present invention.

[Embodiment 1]
A processing method and a cutting device 1 according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a configuration example of the cutting device according to the first embodiment. FIG. 2 is a plan view of a package substrate to be processed by the processing method and cutting device according to the first embodiment. FIG. 3 is a side view of the package substrate shown in FIG. 2. FIG. 4 is a plan view of the back side of the package substrate shown in FIG. 2. FIG. 5 is a perspective view of a package chip obtained by dividing the package substrate shown in FIG. 2. FIG. 6 is a front view showing a first cutting unit and a second cutting unit of the cutting device shown in FIG. 1.

The cutting device shown in FIG. 1 according to the first embodiment is a processing device that performs cutting processing on a package substrate 200, which is a substrate shown in FIGS. 2, 3, and 4, and divides the package substrate 200 into individual package chips 201 (corresponding to chips) shown in FIG. 5 to form the package chips 201.

(Package substrate)
The package substrate 200 to be processed by the cutting device 1 according to the first embodiment is formed in a rectangular plate-like shape in plan view, as shown in Fig. 2. The package substrate 200 includes a rectangular plate-like base substrate 202, and has a device region 204 and a peripheral excess region 205 surrounding the device region 204 on a surface 203 of the base substrate 202. The surface 203 of the base substrate 202 corresponds to the upper surface of the package substrate 200. The base substrate 202 is made of a metal such as a metal containing copper (i.e., a copper alloy).

In the device region 204, a plurality of planned division lines 206 that intersect with each other are set. One of the plurality of planned division lines 206 that intersect with each other extends in a direction parallel to the longitudinal direction of the base substrate 202, and the other planned division line 206 extends in a direction perpendicular to the longitudinal direction of the base substrate 202 and parallel to the width direction of the base substrate 202. A device chip 208 is disposed in a region 207 partitioned by the plurality of planned division lines 206 that intersect with each other. The planned division lines 206 are configured to penetrate the base substrate 202. The region 207 is configured by a part of the base substrate 202, and the device chip 208 is disposed on the back surface 210 (shown in FIG. 4, etc.) side behind the front surface 203. An electrode 209 for connecting the package chip 201 to a wiring substrate or the like is provided on each planned division line 206.

The electrodes 209 are formed from a part of the base substrate 202, and in the first embodiment, are provided at the center of the width of the planned division lines 206, and are formed in a straight line in a direction perpendicular to each planned division line 206. The electrodes 209 are connected to the device chip 208 by wires or the like (not shown).

In the first embodiment, multiple device regions 204 (three in the first embodiment) are arranged at intervals in the longitudinal direction of the base substrate 202. The peripheral surplus region 205 is an area in which no device chips 208 are arranged, and is formed by the base substrate 202. It surrounds the entire periphery of each device region 204 and connects adjacent device regions 204 together.

As shown in Figs. 3 and 4, the package substrate 200 includes a sealing resin 211 that seals (covers) the back surface 210 side of each device region 204. The sealing resin 211 is made of a thermoplastic resin, seals (covers) the device chips 208 and wires arranged on the back surface 210 of the region 207 of the base substrate 202, and is filled in the planned division line 206. On the back surface 210 side of the base substrate 202, the sealing resin 211 seals (covers) the entire device region 204. On the front surface 203 side of the base substrate 202, the sealing resin 211 seals the planned division line 206 while exposing the region 207 where the device chips 208 are arranged and the electrodes 209.

The package substrate 200 is cut at the center of the width of each division line 206 of each device region 204, and the electrodes 209 are divided into two, and the package substrate 200 is divided into individual package chips 201 as shown in FIG. 5. In this way, the package substrate 200 that is the processing target of the processing method and cutting device 1 according to the first embodiment is a QFN substrate in which metal electrodes 209 are arranged on the division lines 206 cut by the cutting blade 21. In the first embodiment, the package substrate 200 is a QFN (Quad Flat Non-leaded Package) substrate in which the electrodes 209 are arranged on the division lines 206, but is not limited thereto, and may be a CSP (Chip Scale Packaging) substrate. In the first embodiment, the package chip 201 divided from the package substrate 200 is a small chip with each side having a length of about 1 mm x 1 mm, i.e., a small chip with a small chip size.

In addition, in the first embodiment, as shown in FIG. 2, the package substrate 200 has alignment marks 212 on both ends of the planned division lines 206 on the surface 203 of the base substrate 202, which indicate the cutting positions of the planned division lines 206 during cutting processing. In the first embodiment, the alignment marks 212 are arranged in positions aligned with the center of each planned division line 206 in the width direction.

The package chip 201 manufactured by dividing the package substrate 200 includes an area 207 of the base substrate 202, a device chip 208 disposed on the back surface 210 of the area 207, electrodes 209, and sealing resin 211, as shown in FIG. 5. The sealing resin 211 seals the device chip 208 and the like while leaving the surface 203 of the area 207 and the electrodes 209 exposed.

In the first embodiment, the package chip 201 has a stepped notch 214 formed in each side surface 213. The notch 214 is parallel to the side surface 213 and flat in a direction perpendicular to both the front surface 203 and the back surface 210, and includes a second side surface 213-1 on the front surface 203 side and a flat surface 213-2 continuing to the second side surface 213-1 and the side surface 213. The flat surface 213-3 is formed flat along both the front surface 203 and the back surface 210. In the region where the electrode 209 is formed, the notch 214 is formed only in the electrode 209 and is not formed in the sealing resin 211. The depth 215 of the notch 214 is set to a predetermined depth 219 that is smaller than the thickness of the electrode 209 and is set in advance at the design stage, etc.

The package chip 201 also has a metal plating layer (not shown) on the surface of the electrode 209. The plating layer improves the wettability of the solder that fixes the package chip 201 to the mounting substrate to the electrode 209. The package chip 201 is mounted on the mounting substrate by fixing the electrode 209 to a metal part (not shown) of the mounting substrate by the solder.

(Cutting device)
The cutting device 1 according to the first embodiment is a processing device that holds the package substrate 200 on the table 10 and performs cutting processing along a plurality of planned division lines 206. In the first embodiment, the cutting device 1 is a processing device (a so-called jig dicer) that holds the package substrate 200, to which no dicing tape is attached, directly on the table 10 and performs a so-called full cut on the package substrate 200 to divide it into package chips 201.

As shown in FIG. 1, the cutting device 1 includes a table 10 that holds the package substrate 200 by suction on a holding surface 11, a sub-chuck table 15, a cutting unit 20 that cuts the package substrate 200 held on the table 10, an imaging unit 30 that photographs the package substrate 200 held on the table 10, and a control unit 100. As shown in FIG. 1 and FIG. 6, the cutting device 1 includes two cutting units 20, i.e., a two-spindle dicer, a so-called facing dual type cutting device.

As shown in FIG. 1, the cutting device 1 also includes a moving unit 40 that moves the table 10 and the cutting unit 20 relative to one another. The moving unit 40 includes an X-axis moving unit 41, a Y-axis moving unit 42, a Z-axis moving unit 43, and a rotational moving unit 44.

The X-axis movement unit 41 moves the table 10 and the rotational movement unit 44 in the X-axis direction parallel to the horizontal direction, which is the machining feed direction, thereby moving the cutting unit 20 and the table 10 relatively along the X-axis direction. The Y-axis movement unit 42 moves the cutting unit 20 in the Y-axis direction parallel to the horizontal direction, which is the indexing feed direction, and perpendicular to the X-axis direction, thereby moving the cutting unit 20 and the table 10 relatively along the Y-axis direction.

The Z-axis movement unit 43 moves the cutting unit 20 in the Z-axis direction, which is perpendicular to both the X-axis direction and the Y-axis direction, which are the cutting feed directions, thereby moving the cutting unit 20 and the table 10 relatively along the Z-axis direction. The rotational movement unit 44 is supported by the X-axis movement unit 41, supports the table 10, and is disposed so as to be movable in the X-axis direction together with the table 10. The rotational movement unit 44 rotates the table 10 around an axis parallel to the Z-axis direction.

The X-axis moving unit 41, the Y-axis moving unit 42, and the Z-axis moving unit 43 each include a well-known ball screw that is rotatable around its axis, a well-known motor that rotates the ball screw around its axis, and a well-known guide rail that supports the table 10 or the cutting unit 20 so that it can move in the X-axis, Y-axis, or Z-axis direction. The rotational moving unit 44 also includes a motor that rotates the table 10 around its axis.

The table 10 holds the package substrate 200 by suction on its upper surface, the holding surface 11. The table 10 is rotated around an axis parallel to the Z-axis direction by the rotational movement unit 44. The table 10 is moved in the X-axis direction together with the rotational movement unit 44 by the X-axis movement unit 41.

The table 10 has a holding surface 11 divided into a plurality of regions by escape grooves 12 into which the cutting blade 21 enters during cutting, and suction holes 13 for sucking the package substrate 200 and package chip 201 are opened in each of the regions divided by the escape grooves 12 of the holding surface 11. The escape grooves 12 are provided at positions corresponding to the planned division lines 206 (positions overlapping the planned division lines 206 of the package substrate 200 held on the holding surface 11) and are recessed from the holding surface 11.

The suction holes 13 are provided at positions corresponding to the package chips 201 (i.e., positions overlapping the package chips 201 of the package substrate 200 held on the holding surface 11) and open in each area of the holding surface 11. In the first embodiment, the suction holes 13 correspond one-to-one to the package chips 201. The suction holes 13 are connected to a suction source via a suction path (not shown).

The sealing resin 211 side of the package substrate 200 is placed on the holding surface 11 of the table 10. The table 10 holds the package substrate 200 and the package chip 201 on the holding surface 11 by suction through the suction holes 13 by a suction source. In the first embodiment, the table 10 is a so-called jig table that holds the package substrate 200, to which no dicing tape is attached, directly on the holding surface 11 by suction, but the present invention is not limited to a jig table.

The sub-chuck table 15 is provided adjacent to the table 10 and holds the dressing board 250 by suction on the holding surface 16. The dressing board 250 is used for flat dressing, in which the tip of the cutting blade of the cutting blade 21 is worn down by cutting with the cutting blade 21, and the tip of the cutting blade is flattened along the axial direction of the cutting unit 20.

The sub-chuck table 15, together with the table 10 and the rotary movement unit 44, is moved in the X-axis direction by the X-axis movement unit 41. The sub-chuck table 15 rotates around the axis together with the table 10 by the rotary movement unit 44.

The cutting unit 20 is a processing unit in which the cutting blade 21 is attached to the spindle 23 and cuts the package substrate 200 held on the table 10. The cutting unit 20 is provided so as to be movable in the Y-axis direction by the Y-axis movement unit 42 with respect to the package substrate 200 held on the table 10, and is provided so as to be movable in the Z-axis direction by the Z-axis movement unit 43. As shown in FIG. 1, the cutting unit 20 is provided on the support frame 3 erected from the device main body 2 via the Y-axis movement unit 42 and Z-axis movement unit 43. The cutting unit 20 is capable of positioning the cutting blade 21 at any position on the holding surface 11 of the table 10 by the Y-axis movement unit 42 and Z-axis movement unit 43.

The cutting unit 20 has a cutting blade 21, a spindle housing 22 that is movable in the Y-axis and Z-axis directions by a Y-axis moving unit 42 and a Z-axis moving unit 43, a spindle 23 that is rotatably mounted on the spindle housing 22 around its axis and has the cutting blade 21 attached to its tip, a spindle motor (not shown) that rotates the spindle 23 around its axis, and a cutting water nozzle 24 that supplies cutting water to the cutting blade 21.

The cutting blade 21 is an extremely thin cutting wheel having a roughly ring shape. The cutting blade 21 is fixed to the tip of the spindle 23. In the first embodiment, the cutting blade 21 is a so-called hub blade that includes a circular base and a circular cutting blade that is disposed on the outer periphery of the circular base and cuts the package substrate 200. The cutting blade is made of abrasive grains such as SiC, alumina, diamond, or CBN (Cubic Boron Nitride), and a bond (binding material) that fixes the abrasive grains such as metal or resin, and is formed to a predetermined thickness. In the present invention, the cutting blade 21 may be a so-called washer blade that is composed only of a cutting blade.

Hereinafter, one of the two cutting units 20 will be referred to as the first cutting unit 20 (indicated by reference number 20-1), and the other will be referred to as the second cutting unit 20 (indicated by reference number 20-2). In addition, as shown in FIG. 6, the cutting blade 21 of the first cutting unit 20-1 will be referred to as the first blade 21 (indicated by reference number 21-1), and the cutting blade 21 of the second cutting unit 20-2 will be referred to as the second blade 21 (indicated by reference number 21-2). In addition, the cutting blade thickness 25-2 of the second blade 21-2 of the second cutting unit 20-2 is thinner than the cutting blade thickness 25-1 of the first blade 21-1 of the first cutting unit 20-1. In addition, in the first embodiment, when the blades 21-1 and 21-2 repeatedly cut the package substrate 200, the cutting blade gradually wears from the tip side, and the corners are removed to form a curved surface (R shape).

The imaging unit 30 is fixed to the first cutting unit 20-1 so as to move integrally with the first cutting unit 20-1. The imaging unit 30 is equipped with an imaging element that captures an image of the area to be divided of the package substrate 200 before cutting, which is held on the table 10. The imaging element is, for example, a CCD (Charge-Coupled Device) imaging element or a CMOS (Complementary MOS) imaging element. The imaging unit 30 captures an image of the package substrate 200 held on the table 10 to obtain an image for performing alignment between the package substrate 200 and the cutting blade 21, and outputs the obtained image to the control unit 100.

The cutting device 1 also includes an X-axis position detection unit (not shown) for detecting the position of the table 10 in the X-axis direction, a Y-axis position detection unit (not shown) for detecting the positions of the cutting units 20-1 and 20-2 in the Y-axis direction, and a Z-axis position detection unit for detecting the positions of the cutting units 20-1 and 20-2 in the Z-axis direction. The X-axis position detection unit and the Y-axis position detection unit can be configured with a linear scale parallel to the X-axis direction or the Y-axis direction, and a reading head. The Z-axis position detection unit detects the positions of the cutting units 20-1 and 20-2 in the Z-axis direction using motor pulses. The X-axis position detection unit, the Y-axis position detection unit, and the Z-axis position detection unit output the positions of the table 10 in the X-axis direction and the lower ends of the cutting blades of the cutting units 20-1 and 20-2 in the Y-axis direction or the Z-axis direction to the control unit 100.

In the first embodiment, the positions of the table 10 of the cutting device 1 and the cutting units 20-1 and 20-2 in the X-axis direction, Y-axis direction, and Z-axis direction are determined based on a predetermined reference position (not shown).

The control unit 100 also controls each of the components of the cutting device 1, including the first cutting unit 20-1, the second cutting unit 20-2, and the imaging unit 30, and causes the cutting device 1 to perform processing operations on the package substrate 200. The control unit 100 is a computer having an arithmetic processing device having a microprocessor such as a CPU (central processing unit), a storage device having a memory such as a ROM (read only memory) or a RAM (random access memory), and an input/output interface device. The arithmetic processing device of the control unit 100 performs arithmetic processing according to a computer program stored in the storage device, and outputs control signals for controlling the cutting device 1 to each of the components of the cutting device 1 via the input/output interface device.

The control unit 100 is connected to a display unit, which is composed of a liquid crystal display device that displays the status of the processing operation and images, and an input unit that the operator uses to register processing content information, etc. The input unit is composed of a touch panel provided on the display unit.

As shown in FIG. 1, the control unit 100 includes an estimation unit 101, a calculation unit 102, and a machining control unit 103 that controls the machining operations of each component of the cutting device 1. The functions of the estimation unit 101, the calculation unit 102, and the machining control unit 103 are realized by the arithmetic processing device performing arithmetic processing according to a computer program stored in the storage device.

The processing method according to the first embodiment is a processing method in which the cutting device 1 half-cuts the package substrate 200 with the first blade 21-1, and then full-cuts with the second blade 21-2, which has a blade thickness 25-2 thinner than the first blade 21-1, to form a package chip 201 with a stepped notch 214 formed in the side surface 213. In other words, the processing method according to the first embodiment is also the processing operation of the cutting device 1. Figure 7 is a flowchart showing the flow of the processing method according to the first embodiment. As shown in Figure 7, the processing method according to the first embodiment includes a half-cut step 1002, a full-cut step 1003, a tip shape confirmation step 1005, a flattening step 1007, etc.

In the cutting device 1, the sealing resin 211 of the package substrate 200 is placed on the holding surface 11 of the table 10, and the dress board 250 is placed on the holding surface 11 of the sub-chuck table 15. In the cutting device 1, the control unit 100 receives the processing conditions input from an input unit or the like, and when the control unit 100 receives a processing start command from an operator or the like, the cutting device 1 performs a processing operation, i.e., a processing method. The processing conditions include the blade thicknesses 25-1 and 25-2 of the blades 21-1 and 21-2, the cutting depth 26 of the first blade 21-1 (shown in FIG. 8), the predetermined depth 219 of the depth 215 of the cutout portion 214 set in advance at the design stage, the thickness of the electrode 209, the type of the first blade 21-1, the type of the package substrate 200, and the like. The cutting depth 26 of the processing conditions is smaller than the thickness of the electrode 209 and is the same as the predetermined depth 219 of the depth 215 of the cutout portion 214 set in advance at the design stage, etc.

When the machining operation is started, the cutting device 1 rotates the spindles 23 of the cutting units 20-1 and 20-2, i.e., the cutting blades 21-1 and 21-1, around the axis, and suction-holds the package substrate 200 on the holding surface 11 of the table 10, and suction-holds the dress board 250 on the holding surface 11 of the sub-chuck table 15. When the machining operation is started, the cutting device 1 determines whether it is time for the machining control unit 103 of the control unit 100 to check the shape of the tip of the cutting blade of the first blade 21-1 (step 1001). The timing for checking the shape of the tip of the cutting blade of the first blade 21-1 is determined by the type of the package substrate 200 and the first blade 21-1, etc. When the cutting device 1 determines that it is not time for the machining control unit 103 of the control unit 100 to check the shape of the tip of the cutting blade of the first blade 21-1 (step 1001: No), it proceeds to the half-cut step 1002.

(Half cut step)
Fig. 8 is a cross-sectional view that typically shows a half-cut step of the processing method shown in Fig. 7. The half-cut step 1002 is a step in which the first blade 21-1 is caused to cut into the package substrate 200 and cut the package substrate 200 along the planned division line 206 with the first blade 21-1 to form the first cut groove 216 and to form the uncut portion 217 below the first cut groove 216. That is, in the half-cut step 1002, the first blade 21-1 cuts the package substrate 200 along the planned division line 206 to form the first cut groove 216 and to form the uncut portion 217 below the first cut groove 216.

In the half-cut step 1002, the cutting device 1 has the processing control section 103 of the control unit 100 control the moving unit 40 to move the table 10 to below the imaging unit 30, image the mark 212 on the package substrate 200 with the imaging unit 30, and perform alignment to align the blades 21-1, 21-2 with the planned division line 206. In the half-cut step 1002, the cutting device 1 has the processing control section 103 of the control unit 100 control each component to relatively move the table 10 and the first blade 21-1 of the cutting unit 20-1 along the X-axis direction, the Y-axis direction, etc., while cutting the cutting edge of the first blade 21-1 into the center of one planned division line 206 in the width direction by a cutting depth of 26 determined by the processing conditions. In the half-cut step 1002, the cutting device 1 cuts the planned division line 206 of the package substrate 200 with the first blade 21-1, as shown in FIG. 8, to form a first cutting groove 216 in the planned division line 206 and also form an uncut portion 217 below the first cutting groove 216.

In the first embodiment, in the half-cut step 1002, the cutting device 1 cuts the tip of the cutting blade of the first blade 21-1 to a depth of 26 to the center of the thickness of each electrode 209, forming a first cutting groove 216 in the electrode 209 at the planned division line 206. Note that the first cutting groove 216 is formed by cutting the tip of the cutting blade of the first blade 21-1 to the center of the thickness of the electrode 209, and is therefore a groove that does not divide the electrode 209 and the package substrate 200, i.e., a half-cut groove.

In the first embodiment, in the half-cut step 1002, the cutting device 1 forms a first cutting groove 216 on one of the planned division lines 206 of the package substrate 200 held by suction on the table 10, but in the present invention, the first cutting grooves 216 may be formed in order on a number of planned division lines 206 determined by processing conditions, etc. In the first embodiment, in the half-cut step 1002, the cutting device 1 forms a first cutting groove 216 on one of the planned division lines 206 of the package substrate 200 held by suction on the table 10, and then proceeds to the full-cut step 1003.

(Full cut step)
Fig. 9 is a cross-sectional view showing a schematic diagram of the full-cut step of the processing method shown in Fig. 7. The full-cut step 1003 is a step of cutting the uncut portion 217 along the first cutting groove 216 with the second blade 21-2 having a blade thickness 25-2 thinner than that of the first blade 21-1 after the half-cut step 1002 is performed. That is, in the full-cut step 1003, the second blade 21-2 is a cutting blade having a blade thickness 25-2 thinner than that of the first blade 21-1, which cuts the uncut portion 217 along the first cutting groove 216.

In the full cut step 1003, the cutting device 1 has the processing control section 103 of the control unit 100 control each component, and while moving the table 10 and the second blade 21-2 of the cutting unit 20-2 relatively along the X-axis direction and the Y-axis direction, etc., the cutting blade of the second blade 21-2 cuts into the remaining cut portion 217 below the first cutting groove 216 formed in the center of the width of one of the planned division lines 206 until it reaches the escape groove 12. In the full cut step 1003, as shown in FIG. 9, the cutting device 1 cuts the center of the width of the remaining cut portion 217 below the first cutting groove 216 formed in the planned division line 206 of the package substrate 200 with the second blade 21-2 to form a second cutting groove 218 that cuts or cuts the remaining cut portion 217. In the full cut step 1003, the cutting device 1 forms a second cutting groove 218 that cuts or cuts the remaining cut portion 217, and divides the package substrate 200 into package chips 201.

At this time, the package substrate 200, i.e., the package chip 201, has a notch 214 formed by the first cutting groove 216, and a side surface 213 formed by the second cutting groove 218. The inner surface of the first cutting groove 216 becomes the second side surface 213-1, the bottom surface of the first cutting groove 216 becomes the flat surface 213-2, the inner surface of the second cutting groove 218 becomes the side surface 213, and the depth 215 of the notch 214 is determined by the cutting depth 26 of the first blade 21-1.

In the first embodiment, in the full cut step 1003, the cutting device 1 cuts the remaining portion 217 below the first cutting groove 216 formed on one of the planned division lines 206 of the package substrate 200 held by suction on the table 10, but in the present invention, the first cutting groove 216 may be formed in order on a number of planned division lines 206 determined by processing conditions, etc. In this case, in the full cut step 1003, it is preferable to cut the remaining portion 217 below the first cutting groove 216 formed in the immediately preceding half cut step 1002. In the first embodiment, in the full cut step 1003, the cutting device 1 cuts the remaining portion 217 below the first cutting groove 216 formed on one of the planned division lines 206 of the package substrate 200 held by suction on the table 10, and then proceeds to step 1004.

The cutting device 1 determines whether the processing control unit 103 of the control unit 100 has formed the first cutting grooves 216 on all of the planned division lines 206 of the package substrate 200 in the half-cut step 1002, cut the remaining cut portions 217 below the first cutting grooves 216 in the full-cut step 1003, and divided the package substrate 200 into individual package chips 201 (step 1004). When the processing control unit 103 of the control unit 100 has formed the first cutting grooves 216 on all of the planned division lines 206 of the package substrate 200 in the half-cut step 1002, cut the remaining cut portions 217 below the first cutting grooves 216 in the full-cut step 1003, and determined that the package substrate 200 has not been divided into individual package chips 201 (step 1004: No), the cutting device 1 returns to step 1001.

When the machining control unit 103 of the control unit 100 determines that it is time to check the shape of the tip of the cutting edge of the first blade 21-1 (step 1001: Yes), the cutting device 1 proceeds to tip shape confirmation step 1005. Here, before the first blade 21-1 of the cutting unit 20-1 of the cutting device 1 is worn, the tip of the cutting edge is formed flat along the axis of the spindle 23, and the curved surface 28 (also called the R shape) of the corner of the tip is small, as shown in Figures 8 and 10, for example. Note that Figure 10 is a cross-sectional view that shows the state before the first blade of the cutting device shown in Figure 1 is worn. Figure 11 is a cross-sectional view that shows the state in which the first blade shown in Figure 10 has been worn. Figure 12 is a cross-sectional view that shows the state in which the first blade shown in Figure 11 has been further worn.

When the first blade 21-1 repeatedly cuts the planned division line 206, it wears down, and for example, as shown in FIG. 11, the curved surface 28 at the corner of the tip of the cutting blade gradually becomes larger, and the boundary 27 between the curved surface 28 and the flat surface along the axis of the spindle 23 gradually moves toward the center in the thickness direction of the cutting blade. When the boundary 27 of the first blade 21-1 is located outside the second cutting groove 218 formed by the second blade 21-2, the cutting depth 26 and the depth 215 of the notch 214 become equal, and the notch 214 of the specified depth 219 can be formed. Also, when the boundary 27 of the first blade 21-1 is located inside the second cutting groove 218 formed by the second blade 21-2, the depth 215 of the notch 214 becomes smaller than the cutting depth 26, and the notch 214 of the depth 215 smaller than the specified depth 219 is formed.

Furthermore, as the first blade 21-1 wears further, for example, as shown in FIG. 12, the tip of the cutting edge may lose its flat surface along the axis and become curved, convexly curved in the outer circumferential direction. This causes the depth 215 of the notch 214 to become smaller than the cutting depth 26, resulting in the formation of a notch 214 with a depth 215 smaller than the predetermined depth 219.

In the first embodiment, the timing for checking the shape of the tip of the cutting edge of the first blade 21-1 in step 1001 is the timing before the first blade 21-1 wears down as shown in FIG. 12, for example, and the depth 215 of the notch 214 becomes smaller than the cutting depth 26, for example, the timing before (just before) the aforementioned boundary 27 penetrates into the inside of the second cutting groove 218. In the first embodiment, the timing for checking the shape of the tip of the cutting edge of the first blade 21-1 in step 1001 is determined for each type of package substrate 200 and first blade 21-1, and is the timing after the start of the processing direction or after cutting a predetermined number of planned division lines 206 after the previous tip shape checking step 1005 is performed.

(Tip shape confirmation step)
FIG. 13 is a side view, partially in section, showing a state in which the cutting blade of the first blade is cut into the peripheral excess area of the base substrate of the package substrate in the tip shape confirmation step of the processing method shown in FIG. 7. FIG. 14 is a plan view of the peripheral excess area of the base substrate of the package substrate on which a cutting mark is formed in the tip shape confirmation step of the processing method shown in FIG. 7. FIG. 15 is a diagram showing an image obtained by imaging the cutting mark by the imaging unit in the tip shape confirmation step of the processing method shown in FIG. 7. FIG. 16 is a diagram showing an image of the tip of the cutting blade of the first blade generated by reducing the length of the image shown in FIG. 15 in the tip shape confirmation step of the processing method shown in FIG. 7. FIG. 17 is a cross-sectional view of the tip of the cutting blade of the first blade on which the cutting mark shown in FIG. 14 is formed. FIG. 18 is a vertical cross-sectional view parallel to the longitudinal direction of the cutting mark shown in FIG. 14. FIG. 19 is a cross-sectional view showing the calculated cutting depth and the like in the tip shape confirmation step of the processing method shown in FIG. 7.

The tip shape confirmation step 1005 is a step for confirming the shape of the tip of the cutting blade of the first blade 21-1. In the first embodiment, in the tip shape confirmation step 1005, the estimation unit 101 of the control unit 100 of the cutting device 1 controls the moving unit 40, etc., to position the first blade 21-1 above the base substrate 202 of the peripheral excess area 205, which is the cutting target of the package substrate 200, as shown in FIG. 13, and lowers the rotating first blade 21-1 along the Z-axis direction to cut with the tip of the cutting blade of the first blade 21-1, and then raises the first blade 21-1 along the Z-axis direction.

Then, the cutting marks 220 shown in FIG. 14 are formed on the surface 203 of the base substrate 202 in the peripheral excess region 205 of the package substrate 200. Thus, in the first embodiment, in the tip shape confirmation step 1005, the cutting device 1 cuts the first blade 21-1 into the surface 203 of the base substrate 202 in the peripheral excess region 205, which is the cutting target of the package substrate 200, and forms the cutting marks 220 on the surface 203 with the first blade 21-1. Also, in the first embodiment, in the tip shape confirmation step 1005, the cutting marks 220 are formed by so-called chopper cutting, in which the first blade 21-1 is raised and lowered relative to the surface 203 of the base substrate 202 in the peripheral excess region 205 of the package substrate 200. The cutting marks 220 are grooves recessed from the surface 203 extending along the X-axis direction, and the shapes of both ends 221 are curved according to the shape of the tip of the cutting blade of the first blade 21-1.

In addition, because the cutting mark 220 is formed by raising and lowering the first blade 21-1 along the Z-axis direction, both ends 221 of the cutting mark 220 are formed as dead ends that gradually approach the surface 203 as they approach both ends 221. Both ends 221 of the cutting mark 220 have the same shape as the tip of the cutting edge of the first blade 21-1.

In tip shape confirmation step 1005, the estimation unit 101 of the control unit 100 of the cutting device 1 controls the moving unit 40 and the like to position the cutting mark 220 below the imaging unit 30. In tip shape confirmation step 1005, the estimation unit 101 of the control unit 100 of the cutting device 1 causes the imaging unit 30 to image the cutting mark 220, and obtains an image 300, an example of which is shown in FIG. 15. In this way, the imaging unit 30 images the cutting mark 220 formed by cutting the first blade 21-1 into the base substrate 202 in the peripheral excess region 205 of the package substrate 200.

In tip shape confirmation step 1005, the estimation unit 101 of the control unit 100 of the cutting device 1 reduces the length of at least a portion of the image 300 including one end 221 of the cutting mark 220 so that the length of at least a portion of the image is the length as viewed from the tangent direction 29 (shown in FIG. 18) of the tip of the cutting blade of the first blade 21-1, and forms an image 400 that approximates the tip of the cutting blade of the first blade 21-1. Specifically, the estimation unit 101 of the control unit 100 divides the image 300 in the longitudinal direction of the cutting mark 220 as shown in FIG. 15.

In the first embodiment, the estimation unit 101 of the control unit 100 divides the image 300 into a plurality of divided images 301, 302, 303, 304, etc., for each length L that can be calculated from one end 221 of the cutting mark 220 using the following formula 1. The control unit 100 stores the following formula 1 in advance. The control unit 100 calculates the length L1 (shown as L in formula 1) of the divided image 302 including one end 221 of the cutting mark 220 that can be calculated using formula 1 corresponding to the value α1 (shown as α in formula 1). Here, the value α1 is, for example, 1 μm, R is the radius of the first blade 21-1, and d is the cutting depth of the cutting mark 220. The divided image 302 is an image of a portion of the cutting mark 220 including one end 221 of the cutting mark 220.

The estimation unit 101 of the control unit 100 removes some of the pixels that make up the divided image 302 so that the length L (L1) of the divided image 302 becomes the value α1. At this time, the control unit 100 removes pixels at equal intervals according to the difference between the length L (L1) and the value α1.

Next, the control unit 100 calculates the length L (L2) of the divided image 303 adjacent to the divided image 302, which corresponds to the value α2 (indicated as α in Equation 1), using Equation 1, where the value α2 is, for example, 1 μm, d is the cutting depth of the cutting mark 220, and R is R-α1. The estimation unit 101 of the control unit 100 removes a part of the pixels constituting the divided image 303 so that the length L (L2) of the divided image 303 becomes the value α2. Furthermore, the control unit 100 calculates the length L (L3) of the divided image 304 adjacent to the divided image 303, which corresponds to the value α3 (indicated as α in Equation 1), using Equation 1, where the value α3 is, for example, 1 μm, d is the cutting depth of the cutting mark 220, and R is R-(α1+α2). The control unit 100 removes a portion of the pixels that make up the divided image 303 so that the length L (L3) of the divided image 304 becomes the value α3.

In this way, the estimation unit 101 of the control unit 100 divides the image 300 into divided images 301, 302, 303, ..., 300N, and calculates the lengths L1, L2, L3, ..., LN of the divided images 302, 303, 304 ... 30N corresponding to each value α1, α2, α3, ..., αN. The estimation unit 101 of the control unit 100 removes some of the pixels of all the divided images 302, 303, 304, ..., 30N to reduce the lengths to values α1, α2, α3, ..., αN. Then, the estimation unit 101 of the control unit 100 combines the reduced divided images 301, 302, 303, 304, ..., 30N to reduce the length of the image 300 as shown in FIG. 16, and generates an image 400 that approximates the shape of the tip of the cutting edge of the first blade 21-1. The shape of the cutting mark 220 in the image 400 shown in FIG. 16 is approximately the same as the cross-sectional shape of the tip of the cutting edge of the first blade 21-1 that formed the cutting mark 220 shown in FIG. 17.

Thus, in embodiment 1, in tip shape confirmation step 1005, the estimation unit 101 of the control unit 100 confirms the shape of the tip of the cutting edge of the first blade 21-1 based on the image 300 of the cutting mark 220 captured by the imaging unit 30.

Next, we will explain the above-mentioned formula 1. As shown in FIG. 10, the imaging unit 30 images one end 221 of the cutting mark 220 from above perpendicular to the surface 203 of the base substrate 202 in the peripheral excess region 205 of the package substrate 200. In FIG. 18, if the center of the first blade 21-1 when the one end 221 of the cutting mark 220 is formed is A, the point extending from the center A in the Z-axis direction and intersecting with the surface 203 of the package substrate 200 is B, and the one end 221 of the cutting mark 220 is C0, the length of side BC0 of triangle ABC0 can be expressed by the following formula 2.

In FIG. 18, if the end of the cutting mark 220 in the divided image 302 away from one end 221 is C1, and the depth of the cutting mark 220 in the radial direction of the first blade 21-1 at the end C1 away from one end 221 of the cutting mark 220 in the divided image 302 is α1 (indicated as α in Equation 3), the length of side BC1 of triangle ABC1 can be expressed by the following Equation 3.

In FIG. 18, the estimation unit 101 of the control unit 100 can obtain equation 1 from equations 2 and 3 by assuming that the longitudinal length of the cutting mark 220 in the divided image 302 is L1 (indicated as L in equation 1). Since the estimation unit 101 of the control unit 100 assumes that the value α1, which is the depth of the cutting mark 220, is 1 μm, and the radius R of the first blade 21-1 and the cutting depth d of the cutting mark 220 are predetermined, it is possible to determine the longitudinal length L1 of the cutting mark 220 in the divided image 302.

The estimation unit 101 of the control unit 100 can determine the longitudinal length L2 of the cutting mark 220 in the divided image 303 by setting the value α2 to 1 μm and R to R-α1 in Equation 1, and can determine the longitudinal length L3 of the cutting mark 220 in the divided image 304 by setting the value α3 to 1 μm and R to R-(α1+α2). The estimation unit 101 of the control unit 100 can similarly determine the lengths L1, L2, L3, ..., LN of all divided images 302, 303, 304, ..., 30N. By reducing the lengths L1, L2, L3, ..., LN of divided images 302, 303, 304, ..., 30N of image 300 to values α1, α2, α3, ..., αN, the lengths of each divided image 302, 303, 304, ..., 30N are reduced so that the length of the cutting mark 220 of each divided image 302, 303, 304, ..., 30N becomes the length as seen from the tangent direction 29 of the tip of the cutting edge of the first blade 21-1.

The estimation unit 101 of the control unit 100 reduces the length of the image 300 by combining the reduced divided images 302, 303, 304, ..., 30N so that the length of the cutting mark 220 in the image 300 becomes the length as seen from the tangent direction 29 of the tip of the cutting edge of the cutting blade 21 at one end 221 of the cutting mark 220. As a result, the image 400 approximating the outer peripheral shape of the cutting blade 21 approximates an image obtained by imaging one end 221 of the cutting mark 220 from the imaging unit 30 (shown by a dotted line in FIG. 18) arranged in the tangent direction 29 of the cutting blade 21 at one end 221 of the cutting mark 220.

In the tip shape confirmation step 1005, the calculation unit 102 of the control unit 100 calculates the cutting depth 26-1 at which the depth 215 of the notch 214 becomes the aforementioned specified depth 219 based on the tip shape of the cutting edge of the first blade 21-1 estimated by the estimation unit 101 and the blade thickness 25-2 of the second blade 21-2. Specifically, since the shape of the inner surface of the first cutting groove 216 is equivalent to the shape of the tip of the cutting blade of the first blade 21-1, and the shape of the inner surface of the second cutting groove 218 is equivalent to the shape of the tip of the cutting blade of the second blade 21-2, for example, the calculation unit 102 of the control unit 100 determines the intersection 222 between the first cutting groove 216 and the second cutting groove 218 based on the tip shape of the cutting blade of the first blade 21-1 estimated by the estimation unit 101 and the blade thickness 25-2 of the second blade 21-2, and calculates the cutting depth 26-1 of the first blade 21-1 when this intersection 222 is located at a predetermined depth 219.

In tip shape confirmation step 1005, the calculation unit 102 of the control unit 100 stores the calculated cutting depth 26-1 in the storage device as a new machining condition. In tip shape confirmation step 1005, the cutting depth 26-1 calculated by the calculation unit 102 of the control unit 100 is greater than the predetermined depth 219 of the depth 215 of the notch 214. In tip shape confirmation step 1005, the calculation unit 102 of the control unit 100 stores the calculated cutting depth 26-1 in the storage device as a new machining condition, and then proceeds to step 1006.

The machining control unit 103 of the control unit 100 determines whether it is a predetermined timing to perform flat dressing on the tip of the cutting edge of the first blade 21-1 (step 1006). The machining control unit 103 of the control unit 100 determines whether the cutting depth 26-1 calculated by the calculation unit 102 in the tip shape confirmation step 1005 is equal to or greater than a value corresponding to the thickness of the electrode 209. The value corresponding to the thickness of the electrode 209 is a value at which the metal constituting the electrode 209 remains in the uncut portion 217 below the first cutting groove 216 formed by cutting the electrode 209, and may be, for example, the thickness of the electrode 209 or a value slightly smaller than the thickness of the electrode 209.

When the machining control unit 103 of the control unit 100 determines in the tip shape confirmation step 1005 that the cutting depth 26-1 calculated by the calculation unit 102 is less than a value corresponding to the thickness of the electrode 209, it determines that it is not the specified timing to perform flat dressing on the tip of the cutting edge of the first blade 21-1 (step 1006: No) and returns to the half-cut step 1002. When the machining control unit 103 of the control unit 100 determines in the tip shape confirmation step 1005 that the cutting depth 26-1 calculated by the calculation unit 102 is equal to or greater than a value corresponding to the thickness of the electrode 209, it determines that it is the specified timing to perform flat dressing on the tip of the cutting edge of the first blade 21-1 (step 1006: Yes) and proceeds to the flattening step 1007.

(Planarization Step)
The flattening step 1007 is a step of correcting the shape of the tip of the cutting edge of the first blade 21-1 at a predetermined timing and flattening it. In the first embodiment, in the flattening step 1007, the machining control section 103 of the control unit 100 of the cutting device 1 controls the moving unit 40 and the like to position the tip of the cutting edge of the rotating first blade 21-1 at a position aligned in the Y-axis direction with the dress board 250 held on the sub-chuck table 15 and below the upper surface of the dress board 250.

In the first embodiment, in the flattening step 1007, the machining control unit 103 of the control unit 100 controls the moving unit 40, etc., to move the first cutting unit 20-1 along the Y-axis direction in a direction approaching the dress board 250, and the tip of the cutting blade of the rotating first blade 21-1 cuts into the upper surface of the dress board 250. In the first embodiment, in the flattening step 1007, the machining control unit 103 of the control unit 100 controls the moving unit 40, etc., to move the first cutting unit 20-1 along the Y-axis direction while causing the tip of the cutting blade of the rotating first blade 21-1 to cut into the upper surface of the dress board 250, thereby performing flat dressing to flatten the tip of the cutting blade of the first blade 21-1 along the axial direction. In the first embodiment, in the flattening step 1007, the machining control section 103 of the control unit 100 controls the moving unit 40 and the like to move the first cutting unit 20-1 a predetermined number of times along the Y-axis direction to flat-dress the first blade 21-1.

In the first embodiment, in the flattening step 1007, the cutting device 1 performs flat dressing on the first blade 21-1 and then returns to the tip shape confirmation step 1005. Note that in the first embodiment, the cutting device 1 returns to the tip shape confirmation step 1005 after the flattening step 1007, but in the present invention, the cutting device 1 may return to the half cut step 1002 after the flattening step 1007.

In the half-cut step 1002 after returning from step 1004 or step 1006, the cutting device 1 has the processing control unit 103 of the control unit 100 control each component to relatively move the table 10 and the first blade 21-1 of the cutting unit 20-1 along the X-axis direction, the Y-axis direction, etc., while cutting the cutting edge of the first blade 21-1 into the center of the width of one of the planned division lines 206 by the cutting depth 26-1 calculated by the calculation unit 102 in the tip shape confirmation step 1005. In the half-cut step 1002, the cutting device 1 cuts the planned division line 206 of the package substrate 200 with the first blade 21-1 to form a first cutting groove 216 in the planned division line 206 and also forms an uncut portion 217 below the first cutting groove 216. In this way, in the half-cut step 1002 after returning from step 1004 or step 1006, the cutting device 1 cuts the first blade 21-1 into the package substrate 200 at a cutting depth 26-1 that is calculated based on the shape of the tip of the cutting edge of the first blade 21-1 confirmed in the tip shape confirmation step 1005 and the blade thickness 25-2 of the second blade 21-2, so that the depth 215 of the notch 214 becomes the predetermined depth 219.

When the processing control section 103 of the control unit 100 forms the first cutting grooves 216 on all of the planned division lines 206 of the package substrate 200 in the half-cut step 1002 and cuts the remaining cut portions 217 below the first cutting grooves 216 in the full-cut step 1003, and determines that the package substrate 200 has been divided into individual package chips 201 (step 1004: Yes), the cutting device 1 ends the processing operation, i.e., the processing method.

As described above, the processing method and cutting device 1 according to the first embodiment checks the shape of the tip of the cutting blade of the first blade 21-1 in the tip shape confirmation step 1005, and sets the cutting depth 26-1 of the first blade 21-1 so that the depth 215 of the notch 214 formed by the shape of the tip of the cutting blade of the first blade 21-1 and the blade thickness 25-2 of the second blade 21-2 is the predetermined depth 219. For this reason, the processing method and cutting device 1 according to the first embodiment can suppress the error of the depth 215 of the notch 214 of the package chip 201 from the predetermined depth 219. As a result, the processing method and cutting device 1 according to the first embodiment have the effect of suppressing the deterioration of the reliability of the inspection of the package chip 201 and the connection failure.

As a result, the processing method and cutting device 1 according to the first embodiment performs flat dressing on the first blade 21-1 at a predetermined timing in the flattening step 1007 to correct the shape of the tip of the cutting blade of the first blade 21-1 to be flat, so that the notch 214 of the predetermined depth 219 can be formed stably. In general, flat dressing, which corrects the shape of the tip of the cutting blade of the cutting blade, takes time (it is not important that the side of the notch is vertical) and reduces productivity. However, the processing method and cutting device 1 according to the first embodiment change the cutting depth 26-1 based on the shape of the tip of the cutting blade of the first blade 21-1 to form the notch 214 of the predetermined depth 219, so that the implementation of flat dressing can be suppressed and a decrease in productivity can be suppressed.

[Modifications]
A processing method and a cutting device 1 according to a modified example of the first embodiment of the present invention will be described with reference to the drawings. Fig. 20 is a side view, partially in cross section, showing a state in which the cutting edge of the first blade is cut into the peripheral excess area of the base substrate of the package substrate in the tip shape confirmation step of the processing method according to the modified example of the first embodiment. Fig. 21 is a plan view of the peripheral excess area of the base substrate of the package substrate on which cutting marks are formed in the tip shape confirmation step of the processing method according to the modified example of the first embodiment. In Figs. 20 and 21, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

The processing method and cutting device 1 according to the modified example of the first embodiment are the same as those of the first embodiment, except that the method of forming the cutting mark 220-1 in the tip shape confirmation step 1005 is different. In the tip confirmation step of the processing method according to the modified example, the cutting device 1 cuts the first blade 21-1 into the planned division line 206 of the package substrate 200 in the same manner as in the half cut step 1002, as shown in FIG. 20, and raises the first blade 21-1 within the outer periphery excess area 205, forming the cutting mark 220-1 shown in FIG. 21 by a so-called chopper cut traverse. The cutting mark 220-1 formed in the modified example is formed extending along the X-axis direction from the outer edge of the base substrate 202 in the outer periphery excess area 205 of the package substrate 200, and the tip 221 is formed in the same shape as in the first embodiment. In the tip confirmation step of the processing method according to the modified example, the cutting device 1 images the area including the tip 221 of the cutting mark 220-1 with the imaging unit 30, confirms the shape in the same manner as in the first embodiment, and calculates the cutting depth 26-1.

The processing method and cutting device 1 according to the modified example check the shape of the tip of the cutting edge of the first blade 21-1 and set the cutting depth 26-1 of the first blade 21-1 so that the depth 215 of the notch 214 is a predetermined depth 219. This has the effect of preventing a decrease in the reliability of the inspection of the package chip 201 and a connection failure, similar to the first embodiment.

The present invention is not limited to the above-mentioned embodiment 1. In other words, various modifications can be made without departing from the gist of the present invention. In the present invention, the processing method and cutting device 1 may hold the silicon piece or dress board 250, which is the cutting object, on the sub-chuck table 15, and cut the first blade 21-1 into the silicon piece or dress board 250 in the tip shape confirmation step 1005 to form the cutting marks 220, 220-1. In addition, in the present invention, in addition to correcting the cutting depth 26-1 during continuous processing, the tip shape confirmation step 1005 may be performed before performing the half cut step 1002 after replacing and dressing the first blade 21-1. In this case, the cutting depth 26-1 in the half cut step 1002 may be adjusted based on the confirmed shape of the tip of the cutting blade of the first blade 21-1.

REFERENCE SIGNS LIST 1 Cutting device 10 Table 20-1 First cutting unit 20-2 Second cutting unit 21-1 First blade 21-2 Second blade 25-2 Blade thickness 26, 26-1 Cutting depth 30 Imaging unit 100 Control unit 101 Estimation unit 102 Calculation unit 200 Package substrate 201 Package chip (chip)
203 Surface (top)
205 Outer peripheral surplus area (object to be cut)
206 planned division line 213 side surface 214 notch portion 215 depth 216 first cutting groove 217 remaining portion 219 specified depth 220, 220-1 cutting marks 1002 half cut step 1003 full cut step 1005 tip shape confirmation step 1007 flattening step

Claims (4)

A processing method for forming a chip having a stepped cutout on a side surface by half-cutting a package substrate having a plurality of intersecting division lines with a first blade and then fully cutting the package substrate with a second blade having a thinner blade thickness than the first blade, comprising:
a half-cutting step of cutting the package substrate with the first blade along the division line to form a first cut groove and to form an uncut portion below the first cut groove;
a full-cut step of cutting the remaining portion along the first cutting groove with the second blade, the second blade being thinner than the first blade, after the half-cut step is performed;
and a tip shape confirmation step of confirming a tip shape of the first blade,
In the half-cut step, the first blade is cut into the package substrate to a cutting depth that results in a predetermined depth of the notch based on the tip shape of the first blade and the blade thickness of the second blade confirmed in the tip shape confirmation step. The processing method according to claim 1, wherein the tip shape confirmation step forms a cutting mark on the upper surface of the package substrate with the first blade, and confirms the tip shape of the first blade based on the cutting mark. The processing method according to claim 1 or 2, further comprising a flattening step for correcting and flattening the tip of the first blade at a predetermined timing. A cutting device for forming a chip having a stepped cutout on a side surface by half-cutting a package substrate having a plurality of intersecting division lines with a first blade and then fully cutting the package substrate with a second blade having a thinner blade thickness than the first blade,
a table for holding the package substrate;
a first cutting unit having a first blade that cuts the package substrate along the intended division lines to form first cutting grooves and to form an uncut portion below the first cutting grooves;
a second cutting unit having a second blade thinner than the first blade for cutting the uncut portion along the first cutting groove;
an imaging unit that images a cutting mark formed by cutting the first blade into an object to be cut;
A control unit for controlling each of the components,
The control unit includes an estimation unit that estimates a tip shape of the first blade based on an image captured by the imaging unit;
a calculation unit that calculates a cutting depth of the first blade based on the tip shape of the first blade and the blade thickness of the second blade estimated by the estimation unit, such that the depth of the notch portion becomes a predetermined depth;
A cutting device comprising:

Images