JP2021125518A - Wafer processing method - Google Patents

Abstract

[Problem] To easily and reliably remove an organic resin film from the front surface of a wafer. [Solution] A wafer processing method for processing a wafer having a plurality of protruding electrodes formed on its front surface, comprising an organic resin film coating step for coating the front surface of the wafer with an organic resin film to bury the plurality of protruding electrodes, a cutting step for holding the rear surface of the wafer on a chuck table and cutting the organic resin film and the protruding electrodes with a cutting tool having a cutting blade to make the height of the protruding electrodes uniform, a surfactant supplying step for supplying a surfactant to the top surface of the organic resin film, and a peeling step for supplying a fluid to the organic resin film to peel off the organic resin film. Preferably, the fluid supplied to the organic resin film in the peeling step is a mixed fluid of water and air. [Selected Figure] Figure 1

Description

The present invention is a wafer for processing a wafer in which a surface is partitioned by a plurality of scheduled division lines intersecting each other, a device is formed in each of the partitioned regions of the surface, and a plurality of protruding electrodes are formed on each device. Regarding the processing method.

In the manufacturing process of device chips used in electronic devices such as mobile phones and personal computers, first, a plurality of planned division lines intersecting each other are set on the surface of a wafer made of a material such as a semiconductor. Then, devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integration) are formed in each area partitioned by the planned division line. Further, the wafer can be formed by thinning the wafer to a predetermined thickness and then dividing the wafer along the planned division line.

In recent years, a mounting technique called flip-chip bonding has been put into practical use in order to save space in a region required for mounting a device chip on a predetermined mounting target. In flip-chip bonding, a plurality of protrusion electrodes called bumps having a height of about 10 μm to 100 μm are formed on the surface side of the device via a wiring substrate, and these protrusion electrodes are made to face the electrodes formed on the mounting target. It is a mounting technology that directly joins. The protruding electrode functions as a terminal of the device chip.

Further, as a semiconductor packaging technology, a technology of directly forming a protruding electrode on the surface of a device and dividing the wafer into individual device chips has been put into practical use. The packaging technique is called WL-CSP (Wafer-level Chip Size Package) (see Patent Document 1). However, since the heights of the plurality of protruding electrodes formed on the surface of the wafer are not always uniform, even if the plurality of protruding electrodes are directly bonded to the electrodes to be bonded, the bonding may not be uniformly performed. be.

Therefore, a technique has been developed to make the heights of each protruding electrode uniform by cutting the head of each protruding electrode using a processing device (bite cutting device) equipped with a tool called a cutting tool having a cutting edge made of diamond. (See Patent Document 2). In the tool cutting device, the wafer is moved in a direction parallel to the surface so that the cutting edge is cut into the head of the protrusion electrode while passing under the tool.

Japanese Unexamined Patent Publication No. 2001-7135 Japanese Unexamined Patent Publication No. 2004-319667

Since the protruding electrode is made of a metal having strong ductility, when the head of the protruding electrode is cut with a bite, the metal is stretched by the bite and burrs extending from the head are generated. Then, when the burr reaches another adjacent protruding electrode, there arises a problem that the protruding electrodes are short-circuited. In particular, when a small device having a size of 5 mm square or less is formed on the surface of the wafer, the distance between the projection electrodes becomes narrow, so that the probability of short circuit occurrence increases.

Therefore, a technique has been studied in which an organic resin film is provided on the surface of a wafer in advance, the protruding electrode is embedded in the organic resin film, and the head of the protruding electrode is cut with a bite together with the organic resin film. In this technique, the generation of burrs from the head of the protruding electrode is inhibited by the organic resin film. Then, after aligning the heights of the heads of the protruding electrodes with a bite, the organic resin film is removed using an organic solvent such as acetone.

However, since the surface of the wafer has an uneven shape due to a device pattern or the like, the organic resin film cannot be sufficiently removed even when acetone is applied, and the organic resin film is partially formed on the surface of the wafer. May remain. Further, in the first place, when a member that dissolves in acetone is formed on the surface of the device, acetone cannot be used because the member dissolves together with the organic resin film.

The present invention has been made in view of the above problems, and an object of the present invention is to easily and surely obtain an organic resin film for preventing the generation of burrs from the protruding electrodes after cutting the protruding electrodes with a cutting tool. It is to provide a processing method of a wafer which can be removed from the surface of a wafer.

According to one aspect of the present invention, it is a method of processing a waiha in which a plurality of protruding electrodes are formed on the surface thereof, and the surface of the waha is coated with an organic resin film to form the plurality of protruding electrodes. An organic resin film coating step to be buried, a cutting step in which the back surface of the wafer is held by a chuck table, the organic resin film and the protruding electrode are cut with a cutting edge, and the height of the protruding electrode is made uniform. A waiha characterized by comprising a surfactant supply step of supplying a surfactant to the upper surface of the organic resin film and a peeling step of supplying a fluid to the organic resin film to peel off the organic resin film. A processing method is provided.

Preferably, the fluid supplied to the organic resin film in the peeling step is a mixed fluid in which water and air are mixed.

Also, preferably, the surfactant supply step is carried out at the same time as the cutting step or the peeling step, or between the cutting step and the peeling step.

In the wafer processing method according to one aspect of the present invention, the surface of the wafer having the protruding electrode is covered with an organic resin film, and then the organic resin film and the protruding electrode are cut with a bite. At this time, the upper surface of the organic resin film is slightly damaged. When the surfactant is supplied to the upper surface of the organic resin film in this state, the damage promotes the penetration of the surfactant into the organic resin film, so that the surfactant easily reaches the surface of the wafer.

When the surfactant reaches the surface of the wafer, the adhesion between the organic resin film and the surface of the wafer is reduced. Therefore, the organic resin film can be sufficiently removed by the action of a fluid without using an organic solvent such as acetone.

Therefore, according to the present invention, there is provided a method for processing a wafer, which can easily and surely remove an organic resin film for preventing the generation of burrs from the protruding electrode from the surface of the wafer after cutting the protruding electrode with a cutting tool.

It is a perspective view which shows typically the tool cutting apparatus. It is a perspective view which shows typically the organic resin film coating step. FIG. 3A is a perspective view schematically showing a wafer whose surface is coated with an organic resin film, and FIG. 3B is a cross section schematically showing a wafer whose surface is coated with an organic resin film. It is a figure. FIG. 4A is a side view schematically showing a cutting step and a surfactant supply step, and FIG. 4B is a top view schematically showing a cutting step and a surfactant supply step. FIG. 5 (A) is a top view schematically showing a wafer in which the protruding electrode is exposed from the organic resin film, and FIG. 5 (B) is a cross section schematically showing the wafer in which the protruding electrode is exposed from the organic resin film. It is a figure. FIG. 6A is a perspective view schematically showing a peeling step, and FIG. 6B is a cross-sectional view schematically showing a wafer from which the organic resin film has been peeled off. FIG. 7A is a flowchart showing the flow of each step of an example of the wafer processing method, and FIG. 7B is a flowchart showing the flow of each step of another example of the wafer processing method.

An embodiment according to one aspect of the present invention will be described with reference to the accompanying drawings. First, a wafer to be processed by the wafer processing method according to the present embodiment will be described. FIG. 2 and the like include a perspective view schematically showing the wafer 1.

The wafer 1 is, for example, a substantially disk-shaped substrate made of a material such as silicon, SiC (silicon carbide), or other semiconductor, or a material such as sapphire, glass, or quartz. A plurality of scheduled division lines 3 are set in a grid pattern on the surface 1a of the wafer 1, and devices 5 such as ICs and LSIs are formed in each region partitioned by the scheduled division lines 3. Finally, when the wafer 1 is divided along the scheduled division line 3, individual device chips are formed.

A plurality of protruding electrodes 7 called bumps are formed on the surface 1a of the wafer 1. The protruding electrode 7 is made of, for example, a metal such as copper or lead. A plurality of protruding electrodes 7 are arranged on the surface of each device 5, and serve as connection terminals when each device chip formed from the wafer 1 is mounted on a predetermined mounting target. The height of the protruding electrode 7 from the surface 1a of the wafer 1 is, for example, 30 μm to 50 μm.

Since the heights of the plurality of protruding electrodes 7 are not always uniform, even if the plurality of protruding electrodes 7 are directly bonded to the electrodes to be mounted, the bonding may not be uniformly performed. Therefore, the head of the protrusion electrode 7 is cut with a tool called a tool to make the heights of the protrusion electrodes 7 uniform. Next, the cutting tool used in the wafer processing method according to the present embodiment will be described with reference to FIG. FIG. 1 is a perspective view schematically showing a cutting tool 2 for cutting a wafer 1 with a cutting tool.

The tool cutting device 2 has a base 4 that supports each configuration. Cassette mounting bases 6a and 6b are provided on the upper surface of the front side portion of the base 4. For example, a cassette 8a containing a wafer 1 before cutting is placed on the cassette mounting table 6a. On the cassette mounting table 6b, for example, a cassette 8b for accommodating the wafer 1 after cutting is placed. On the base 4, a transfer robot 10 that conveys the wafer 1 is installed adjacent to the cassette mounting tables 6a and 6b.

Further, a plurality of positioning pins arranged on the circumference are provided on the upper surface of the front side portion of the base 4, and the plurality of positioning pins are interlocked and moved inward in the radial direction to hit the wafer 1 against the wafer 1. A positioning table 12 for positioning at a predetermined position is arranged. Further, a loading mechanism (loading arm) 14 for mounting the wafer 1 on the chuck table 20, a unloading mechanism (unloading arm) 16 for unloading the wafer 1 from the chuck table 20, and cleaning for cleaning and spin-drying the cut wafer 1. The unit 50 and the like are arranged.

An opening 4a is provided on the upper surface of the rear portion of the base 4. Inside the opening 4a, an X-axis moving table 18 on which a chuck table 20 for sucking and holding the wafer 1 is mounted is provided. The X-axis movement table 18 can be moved in the X-axis direction by an X-axis direction movement mechanism (not shown). The X-axis moving table 18 is positioned in a carry-in / out area 22 on which the wafer 1 is attached / detached on the chuck table 20 and a processing area 24 in which the wafer 1 sucked and held on the chuck table 20 is cut by a cutting tool.

The upper surface of the chuck table 20 is a holding surface 20a for holding the wafer 1. The chuck table 20 is internally provided with a suction path having one end connected to a holding surface 20a of the chuck table 20 and the other end connected to a suction source (not shown). When the suction source is operated, a negative pressure acts on the wafer 1 placed on the holding surface 20a, and the wafer 1 is sucked and held by the chuck table 20. The chuck table 20 includes, for example, a porous ceramic plate that is exposed upward and constitutes a holding surface 20a.

A tool cutting unit 26 for cutting the wafer 1 with a tool is arranged above the processing area 24. A support portion 28 is erected at the rear end of the base 4 of the tool cutting device 2, and the tool cutting unit 26 is supported by the support portion 28. A pair of Z-axis guide rails 30 extending in the Z-axis direction are provided on the front surface of the support portion 28, and a Z-axis moving plate 32 is slidably attached to each Z-axis guide rail 30.

A nut portion (not shown) is provided on the back surface side (rear surface side) of the Z-axis moving plate 32, and a Z-axis ball screw 34 parallel to the Z-axis guide rail 30 is screwed into the nut portion. ing. A Z-axis pulse motor 36 is connected to one end of the Z-axis ball screw 34.

When the Z-axis ball screw 34 is rotated by the Z-axis pulse motor 36, the Z-axis moving plate 32 moves in the Z-axis direction along the Z-axis guide rail 30. A cutting tool 26 is fixed to the lower portion on the front surface side of the Z-axis moving plate 32. When the Z-axis moving plate 32 is moved in the Z-axis direction, the tool cutting unit 26 can be moved in the Z-axis direction.

The tool cutting unit 26 includes a spindle 40 that is rotated by a motor connected to the base end side, and a tool wheel 44 that is fixed to a mount 42 arranged on the tip end side of the spindle 40 by a fixture 46. The motor is provided in the spindle housing 38, and when the motor is operated, the bite wheel 44 rotates according to the rotation of the spindle 40.

A bite 52 (see FIG. 4A and the like) is mounted on the lower surface of the bite wheel 44. The cutting tool 52 is provided with a cutting edge 52a (see FIG. 4A) that comes into contact with the wafer 1 and cuts the wafer 1 with a tool. The cutting edge 52a is formed of, for example, diamond.

When cutting the protrusion electrode 7 with the tool 52, the tool cutting unit 26 is lowered along the Z-axis direction, and the lower end of the cutting edge 52a is positioned at a predetermined height position. Here, the predetermined height position is a height position that is higher by the finished height of the protrusion electrode 7 from the surface 1a of the wafer 1 placed on the chuck table 20.

Then, the bite wheel 44 is rotated by rotating the spindle 40, and the chuck table 20 is moved in the X-axis direction by the X-axis direction moving mechanism, and the waiha 1 is moved so as to pass under the bite wheel 44. Then, the cutting edge 52a of the rotating bite 52 comes into contact with the head of the protrusion electrode 7, the protrusion electrode 7 is cut, and the protrusion electrode 7 becomes the finished height.

When the wafer 1 is cut with the cutting tool 52, processing heat is generated and the cutting edge 52a of the cutting tool 52 is worn. Further, when cutting is performed, cutting chips are generated, and the cutting chips are scattered on the surface 1a of the wafer 1. Therefore, on the side of the processing region 24, an injection nozzle 48 that injects a cutting fluid such as pure water into the cutting tool 52 is arranged.

The injection nozzle 48 has, for example, a function of injecting cutting fluid into a part of a region through which the bite 52 passes due to the rotation of the bite wheel 44. When cutting the wafer 1 with the cutting tool 52, if the cutting fluid is injected from the injection nozzle 48 to the cutting tool 52 and the wafer 1, the processing heat and processing debris can be removed. Then, the used cutting fluid is discharged from the drain port 4b formed in the opening 4a of the base 4.

The cut wafer 1 is washed by the washing unit 50. When the unloading mechanism (unloading arm) 16 is used, the wafer 1 can be transported to the cleaning unit 50 from the chuck table 20 located in the loading / unloading area 22. The cleaning unit 50 includes a spinner table 50a capable of rotating at high speed while holding the wafer 1 and an injection nozzle 50b (see FIG. 6A) capable of supplying the cleaning liquid 50c (see FIG. 6A) to the surface 1a of the wafer 1 held by the spinner table 50a. 6 (A)).

In the tool cutting device 2 described above, the heights of the plurality of protrusion electrodes 7 can be made uniform by cutting the heads of the plurality of protrusion electrodes 7 formed on the surface 1a of the wafer 1 with the tool 52. However, when the spindle 40 is rotated to cut the protrusion electrode 7 with the cutting tool 52, the upper end portion of the protrusion electrode 7 is dragged by the cutting tool 52, and a protrusion called a burr is generated from the upper end portion along the traveling direction of the cutting tool 52. do.

Then, when the burr reaches the other protruding electrodes 7, there arises a problem that the protruding electrodes 7 are short-circuited with each other. In particular, when a small device 5 having a size of 5 mm square or less is formed on the surface 1a of the wafer 1, the distance between the protruding electrodes 7 becomes narrow, so that the probability of short circuit occurrence increases.

Therefore, a technique of burying the protrusion electrode 7 in the organic resin film by forming an organic resin film that covers the surface 1a of the wafer 1 in advance, and cutting the head of the protrusion electrode 7 together with the organic resin film with a bite 52. Is being considered. In this technique, the generation of burrs from the head of the protruding electrode 7 is inhibited by the organic resin film.

Here, an apparatus for providing an organic resin film on the surface 1a of the wafer 1 will be described. FIG. 2 is a perspective view schematically showing a spin coater 9 as an example of the device. The spin coater 9 includes a support table 9b for supporting the wafer 1 and a discharge nozzle 9a arranged above the center of the support table 9b. The support table 9b can rotate at high speed around an axis perpendicular to the upper surface with the wafer 1 resting on the upper surface. Further, the discharge nozzle 9a can discharge the liquid organic resin film material 11 onto the surface 1a of the wafer 1 placed on the upper surface of the support table 9b.

When the liquid organic resin film material 11 is discharged to the discharge nozzle 9a while the support table 9b is rotated at high speed, the organic resin film material 11 spreads from the center of the wafer 1 to the outer peripheral portion due to centrifugal force. Then, when the organic resin film material 11 is dried and solidified, an organic resin film 13 having a uniform thickness can be formed on the surface 1a of the wafer 1.

Here, for the organic resin film 13, for example, a photoresist material used in photolithography performed in a semiconductor device manufacturing process can be used. For example, for the organic resin film 13, a positive photoresist material containing PGMEA (propylene glycol monomethyl ether acetate) as a main component can be used.

It is necessary to cut the protrusion electrode 7 embedded in the organic resin film 13 with a bite 52 to make the heights of the protrusion electrodes 7 uniform, and then remove the organic resin film 13 from the surface 1a of the wafer 1. Conventionally, an organic solvent such as acetone has been used to remove the organic resin film 13.

However, the surface 1a of the wafer 1 is formed with an uneven shape due to a pattern or the like constituting the device 5. Therefore, the organic resin film 13 that follows the uneven shape may not be sufficiently removed by acetone, and in that case, the organic resin film 13 partially remains on the surface 1a of the wafer 1. Further, when a member that dissolves in acetone is formed on the surface of the device 5, acetone cannot be used because the member dissolves together with the organic resin film 13.

Further, a method of applying thermal stress to the wafer 1 cut by the cutting tool 52 to change the quality of the organic resin film 13 is also conceivable. However, in this case, the cut flat upper surface of the protruding electrode 7 serving as the terminal of the device 5 is altered, and the performance of the protruding electrode 7 as a terminal is deteriorated.

Therefore, in the wafer processing method according to the present embodiment, the surfactant is made of an organic resin so that the organic resin film 13 can be easily and surely removed from the surface 1a of the wafer 1 after the protruding electrode 7 is cut with the bite 52. It acts on the membrane 13. Next, a method for processing the wafer according to the present embodiment will be described. FIG. 7A shows a flowchart showing the flow of each step of an example of the wafer processing method according to the present embodiment. Each step will be described in detail below.

First, in the wafer processing method according to the present embodiment, the surface 1a of the wafer 1 is covered with the organic resin film 13, and a plurality of protruding electrodes 7 formed on the surface 1a of the wafer 1 are embedded in the organic resin film 13. The organic resin film coating step S10 is carried out. FIG. 2 is a perspective view schematically showing the organic resin film coating step S10. The organic resin film coating step S10 is carried out, for example, by the spin coater 9.

However, the organic resin film 13 may be arranged on the surface 1a of the wafer 1 by using another device. The organic resin film coating step S10 may be carried out by, for example, a printing method, an inkjet method, or the like. Hereinafter, the organic resin film coating step S10 will be described by taking the case where the spin coater 9 is used as an example, but the method of forming the organic resin film 13 in the wafer processing method according to the present embodiment is not limited to this.

In the organic resin film coating step S10, first, the wafer 1 is placed on the support table 9b of the spin coater 9. At this time, the position of the wafer 1 is adjusted so that the center of the upper surface, which is the center of rotation of the support table 9b, and the center of the surface 1a of the wafer 1 overlap. Next, the liquid organic resin film material 11 is discharged from the discharge nozzle 9a while rotating the support table 9b, and is dropped onto the center of the surface 1a of the wafer 1. Then, the organic resin film material 11 spreads on the surface 1a of the wafer 1 due to the centrifugal force, and the organic resin film 13 having a uniform thickness is formed on the wafer 1.

FIG. 3A is a perspective view schematically showing a wafer 1 in which the organic resin film 13 is arranged on the surface 1a. In FIG. 3A, a broken line shows a structure or the like that is buried in the organic resin film 13 and cannot be directly seen from the outside. Further, FIG. 3B is a cross-sectional view schematically showing a wafer 1 in which the organic resin film 13 is arranged on the surface 1a. As shown in FIG. 3B, the protruding electrode 7 is covered with the organic resin film 13.

Next, a cutting step S20 for aligning the heights of the protruding electrodes 7 is performed. The cutting step S20 is performed by the tool cutting device 2 shown in FIG. The wafer 1 to be cut by the tool cutting device 2 is carried into the tool cutting device 2 in a state of being housed in the cassette 8a, for example. When the cassette 8a is placed on the cassette mounting table 6a, the wafer 1 is taken out from the cassette 8a by the transfer robot 10.

The transfer robot 10 carries the wafer 1 into the positioning table 12, and operates the positioning table 12 to align the center of the wafer 1 with the center of the positioning table 12. Then, the wafer 1 is placed on the holding surface 20a of the chuck table 20 placed on the X-axis moving table 18 positioned in the loading / unloading region 22 by the loading mechanism (loading arm) 14. At this time, the back surface 1b side of the wafer 1 is turned downward, and the back surface 1b is brought into contact with the holding surface 20a.

After the wafer 1 is placed on the holding surface 20a of the chuck table 20, the suction source (not shown) of the chuck table 20 is operated to apply a negative pressure to the wafer 1, and the back surface 1b of the wafer 1 becomes the chuck table 20. Is sucked and held.

Next, the tool cutting unit 26 is lowered, and the lower end of the cutting edge 52a is positioned at a predetermined height position corresponding to the finishing height of the protrusion electrode 7 of the wafer 1. Further, the X-axis moving table 18 is moved toward the machining area 24. Then, the chuck table 20 is moved in the X-axis direction while rotating the spindle 40 and rotating the bite wheel 44. Then, the upper part of the organic resin film 13 and the upper part of the protrusion electrode 7 are cut by the cutting edge 52a of the cutting tool 52. The moving speed of the X-axis moving table 18 at this time is, for example, about 2 mm / sec.

FIG. 4A is a side view schematically showing the cutting step S20, and FIG. 4B is a top view schematically showing the cutting step S20. When cutting the wafer 1 with the cutting tool 52, the cutting fluid 48a composed of pure water or the like is injected from the injection nozzle 48 toward the region through which the cutting tool 52 passes, and the cutting fluid 48a is supplied to the surface 1a of the wafer 1. do.

When the wafer 1 is cut by the cutting tool 52, the heights of the plurality of protruding electrodes 7 are made uniform to a predetermined finishing height. At this time, since the organic resin film 13 is arranged around the protrusion electrode 7, the generation of burrs from the protrusion electrode 7 is suppressed. The height of the protruding electrode 7 is preferably, for example, 20 μm to 40 μm. Then, the protruding electrode 7 is exposed from the organic resin film 13.

After performing the cutting step S20, the surfactant supply step S30 for supplying the surfactant to the organic resin film 13 remaining on the surface 1a of the wafer 1 is carried out. The surfactant supply step S30 is carried out, for example, in the machining region 24 of the tool cutting apparatus 2 following the cutting step S20. In this case, in the surfactant supply step S30, the surfactant is supplied to the upper surface of the organic resin film 13 by injecting an injection liquid 48b such as pure water containing the surfactant from the injection nozzle 48.

Here, as the surfactant, for example, various surfactants such as nonionic type, cationic type, anion type, and amphoteric type can be used. When the organic resin film 13 is cut with the cutting tool 52 together with the protruding electrode 7 in the cutting step S20, a minute scratch is formed on the upper surface of the organic resin film 13 by the cutting edge 52a of the cutting tool 52. Therefore, when the surfactant is supplied to the upper surface, the surfactant easily permeates into the inside of the organic resin film 13 and the adhesion between the organic resin film 13 and the wafer 1 is lowered, so that the organic resin film 13 is pressed. It can be easily removed.

The surfactant supply step S30 may be carried out at the same time as the cutting step S20. That is, a surfactant is mixed in advance in the cutting fluid 48a ejected from the injection nozzle 48 to the surface 1a of the wafer 1, and in the cutting step S20, the cutting fluid 48a mixed with the surfactant is mixed with the surface 1a of the wafer 1. Spray on. That is, the cutting step S20 and the surfactant supply step S30 may be performed at the same time.

The wafer 1 cut by the cutting tool 52 is conveyed to the cleaning unit 50 and cleaned by the cleaning unit 50. The surfactant supply step S30 may be performed in the cleaning unit 50 of the tool cutting device 2, and may be performed before cleaning or at the same time as cleaning. That is, the surfactant supply step S30 may be carried out in the cleaning unit 50 before the peeling step S40 or at the same time as the peeling step S40. In any case, the wafer 1 cut by the cutting tool 52 is conveyed to the cleaning unit 50.

When transporting the wafer 1, first, the X-axis moving table 18 is moved to the loading / unloading area 22 to release the suction by the chuck table 20. Then, the wafer 1 is held by the unloading mechanism (unloading arm) 16 and the wafer 1 is carried out to the cleaning unit 50. FIG. 6A is a perspective view schematically showing a state in which the wafer 1 is cleaned by the cleaning unit 50.

The injection nozzle 50b included in the cleaning unit 50 is provided with an injection port facing the surface 1a of the wafer 1 at one end, and the other end is connected to the high pressure air source 50d and the high pressure water source 50e. The high-pressure air source 50d can supply high-pressure air of, for example, about 3 atm, and the high-pressure water source 50e can supply pure water of high pressure of, for example, about 3 atm. Then, from the injection port of the injection nozzle 50b, a cleaning liquid 50c composed of a mixed fluid in which high-pressure air supplied from the high-pressure air source 50d and high-pressure pure water supplied from the high-pressure water source 50e is injected is injected. Will be done.

Further, when the surfactant supply step S30 is carried out in the cleaning unit 50, for example, the surfactant is mixed in advance with the pure water of the high-pressure water source 50e. In this case, high-pressure pure water mixed with a surfactant is supplied from the high-pressure water source 50e. Alternatively, the cleaning unit 50 may include a dedicated supply nozzle (not shown) for injecting a liquid such as pure water mixed with a surfactant in addition to the injection nozzle 48.

When the surfactant supply step S30 is carried out in the cleaning unit 50 before the peeling step S40 is carried out, the spinner table 50a (see FIG. 1) on which the wafer 1 is placed is rotated at high speed, and the surface 1a of the wafer 1 is surface-active. Supply the agent.

In the wafer processing method according to the present embodiment, a peeling step S40 is performed in which a fluid is supplied to the organic resin film 13 to peel the organic resin film 13 from the surface 1a of the wafer 1. In the peeling step S40, the spinner table 50a on which the wafer 1 is placed is rotated at high speed, and a high-pressure mixed fluid in which air and pure water are mixed is injected from the injection nozzle 50b onto the surface 1a of the wafer 1. When the surfactant supply step S30 is carried out at the same time as the peeling step S40, the surfactant is mixed in advance with the pure water constituting the mixed fluid.

When a surfactant is supplied to the upper surface of the organic resin film 13 which has been cut by a cutting tool 52 and has minute scratches formed on the upper surface, the surfactant permeates into the organic resin film 13 and reaches the surface 1a of the wafer 1. .. Then, the adhesion between the surface 1a of the wafer 1 and the organic resin film 13 is reduced, and the organic resin film 13 can be easily peeled off. Therefore, when the mixed fluid is supplied to the surface 1a of the wafer 1, the organic resin film 13 is easily peeled off and the surface 1a of the wafer 1 is washed.

For example, regardless of the wafer processing method according to the present embodiment, when the surfactant supply step S30 is not carried out, the adhesion between the organic resin film 13 and the surface 1a of the wafer 1 does not decrease, so that air and pure water are separated from each other. The organic resin film 13 cannot be peeled off with the mixed fluid. In that case, the organic resin film 13 is peeled off using an organic solvent such as acetone.

However, when a member that dissolves in acetone is formed on the surface of the device 5, acetone cannot be used because the member dissolves together with the organic resin film 13. Further, even if acetone can be used, since the surface 1a of the wafer 1 has a concavo-convex shape due to a pattern or the like constituting the device 5, the residue of the organic resin film 13 tends to remain in the concavo-convex shape.

On the other hand, in the wafer processing method according to the present embodiment, the adhesive force between the organic resin film 13 and the wafer 1 is reduced by supplying the surfactant to the upper surface of the organic resin film 13. Therefore, it is not necessary to use a strong organic solvent such as acetone, and it is sufficient to inject a mixed fluid of air and pure water used for cleaning the cut wafer 1 onto the surface 1a of the wafer 1 to obtain an organic resin film. 13 can be peeled off. Further, the residue of the organic resin film 13 does not remain on the uneven shape of the surface 1a of the wafer 1.

The wafer processing method according to the present embodiment can be carried out only by mixing a surfactant with the cutting fluid 48a and the cleaning liquid 50c supplied to the wafer 1 by the tool cutting apparatus 2. That is, in the wafer processing method shown in FIG. 7B, the surfactant supply step S30 can be carried out at the same time as the cutting step S20 or the peeling step S40. In particular, since minute scratches are formed on the upper surface of the organic resin film 13 by the bite 52, the surfactant easily permeates into the organic resin film 13, which is effective in removing the organic resin film 13 cut by the bite 52. Is.

The wafer 1 cleaned by the cleaning unit 50 while the peeling step S40 is performed is housed in the cassette 8b mounted on the cassette mounting table 6b by the transfer robot 10. By each step described above, the height of the protruding electrode 7 formed on the surface 1a of the wafer 1 becomes uniform. Since the organic resin film 13 prevents the generation of burrs, short circuits between the protruding electrodes 7 do not occur.

The present invention is not limited to the description of the above embodiment, and can be implemented with various modifications. In the above embodiment, the case where the surfactant supply step S30 and the peeling step S40 are carried out in the tool cutting apparatus 2 has been described, but one aspect of the present invention is not limited to this. That is, the supply of the surfactant to the surface 1a of the wafer 1 and the peeling of the organic resin film 13 may be performed outside the cutting tool 2.

In this case, after performing the cutting step S20, the wafer 1 is washed by the washing unit 50, and the wafer 1 is housed in the cassette 8b. After that, the wafer 1 is carried into a peeling device provided with a surfactant supply nozzle. Then, in the peeling device, the surfactant is supplied to the surface 1a of the wafer 1, and then a mixed fluid of air and water is supplied to the wafer 1 to peel the organic resin film 13. In this case, it is not necessary to prepare a surfactant in the tool cutting device 2.

The structure, method, and the like according to the above-described embodiment can be appropriately modified and implemented as long as they do not deviate from the scope of the object of the present invention.

1 Waha 1a Front surface 1b Back surface 3 Scheduled division line 5 Device 7 Protruding electrode 9 Spin coater 9a Discharge nozzle 9b Support table 11 Organic resin film material 13 Organic resin film 2-byte cutting device 4 Base 4a Opening 6a, 6b Cassette mounting table 8a, 8b Cassette 10 Transfer robot 12 Positioning table 14 Loading mechanism (loading arm)
16 Unloading mechanism (unloading arm)
18 X-axis moving table 20 Chuck table 20a Holding surface 22 Carry-in / out area 24 Machining area 26 Tool cutting unit 28 Support part 30 Z-axis guide rail 32 Z-axis moving plate 34 Z-axis ball screw 36 Z-axis pulse motor 38 Spindle housing 40 Spindle 42 Mount 44 Tool Wheel 46 Fixture 48 Injection Nozzle 48a Cutting Fluid 48b Injection Liquid 50 Cleaning Unit 50a Spindle Table 50b Injection Nozzle 50c Cleaning Liquid 50d High Pressure Air Source 50e High Pressure Water Source 52 Bit 52a Cutting Blade

Claims (3)

This is a wafer processing method for processing a wafer in which a plurality of protruding electrodes are formed on the surface.
An organic resin film coating step in which the surface of the wafer is coated with an organic resin film and a plurality of the protruding electrodes are embedded.
A cutting step in which the back surface of the waiha is held by a chuck table, the organic resin film and the protrusion electrode are cut with a cutting edge, and the heights of the protrusion electrodes are made uniform.
A surfactant supply step of supplying a surfactant to the upper surface of the organic resin film, and
A peeling step of supplying a fluid to the organic resin film to peel off the organic resin film,
A method of processing a wafer, which is characterized by being provided with. The method for processing a wafer according to claim 1, wherein the fluid supplied to the organic resin film in the peeling step is a mixed fluid in which water and air are mixed. The method for processing a wafer according to claim 1, wherein the surfactant supply step is performed at the same time as the cutting step or the peeling step, or between the cutting step and the peeling step.

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