JP2021114528A - Wafer processing system and wafer processing method - Google Patents

Abstract

To provide a wafer processing system and a wafer processing method that appropriately perform blade processing for a groove in which laser processing is performed.SOLUTION: A laser processing apparatus processes a groove by means of a laser beam along a division schedule line of a wafer, in which the division schedule line is formed on a surface, acquires positional deviation information indicating positional deviation of the groove relative to the division schedule line by imaging a wafer surface, and stores the positional deviation information in a storage unit by associating with unique information of the wafer. A blade dicing apparatus acquires the positional deviation information that is associated with the unique information of the wafer, in which the groove is formed from the storage unit, and performs cutting work of the wafer, in which the groove is formed, along the groove by means of a blade, on the basis of the acquired positional deviation information.SELECTED DRAWING: Figure 5

Description

The present invention relates to a wafer processing system and a wafer processing method, and particularly relates to a technique of grooving by laser processing and then dicing with a blade.

As the performance of semiconductor devices increases, the number of wafers having a film having a weak mechanical strength (for example, a Low-k film or a Hi-k film) on the surface of the device is increasing. When this wafer is blade-diced, the film may be damaged or peeled off due to a mechanical load during dicing. When this peeling reaches the device, it becomes a defective chip and causes a decrease in yield. In order to suppress this decrease in yield, a process of removing a fragile film on a blade dicing processing line by laser processing with a small mechanical load is generally used before blade dicing (see Patent Document 1). .. In this process, dicing is performed using two units, a preceding laser processing device and a succeeding blade dicing device.

Further, in recent years, the processing line has been narrowed in order to reduce the chip size and increase the number of chips taken from one wafer due to the high performance of the chips. For this reason, the machining groove width is becoming smaller in both laser machining and blade machining, and more accurate machining is required.

Japanese Unexamined Patent Publication No. 2005-064231

In the above process, blade dicing needs to machine the center of the laser-machined groove. This is because if the blade of the blade does not enter the laser machining groove, the film is peeled off due to a mechanical load. That is, the blade dicing in this process needs to recognize the chip pattern and the pre-machined laser groove.

When the apparatus corrects the machining position in the preceding laser machining process, the relative position of the chip and the laser machining groove from the machining line shifts from the previous machining line to the correct position. However, since this correction position cannot be grasped by the subsequent blade dicing, the laser machining groove and the blade machining position are relatively deviated from the line. In order to prevent this, it is necessary to recognize the laser machining groove position on all machining lines during blade dicing, but this is time-consuming and impractical.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a wafer processing system and a wafer processing method for appropriately blade processing a laser-processed groove.

One aspect of the wafer processing system for achieving the above object is a wafer processing system including a laser processing device, a blade dicing device, and a storage unit, and the laser processing device has a line to be divided on the surface. By relatively moving the first stage that holds the formed wafer, the laser irradiation unit that irradiates the surface of the wafer with laser light, and the first stage and the laser irradiation unit, along the planned division line of the wafer. A grooving control unit that processes grooves with laser light, an acquisition unit that acquires position deviation information indicating the position deviation of the groove with respect to the planned division line by imaging the surface of the wafer with the imaging unit, and a wafer that obtains the position deviation information. The blade dicing device is provided with a storage control unit that is associated with the unique information of the above and stored in the storage unit. , The position information acquisition unit that acquires the position shift information corresponding to the wafer from the storage unit, the second stage that holds the wafer, the blade that cuts the wafer, and the second stage and blade based on the acquired position shift information. It is a wafer processing system including a cutting processing control unit that cuts a wafer along a groove by a blade by moving it relatively.

According to this aspect, the laser-machined groove can be appropriately bladed.

The imaging unit is preferably arranged on the downstream side of the laser irradiation unit with respect to the relative moving directions of the first stage and the laser irradiation unit. As a result, the surface of the wafer can be imaged by the imaging unit immediately after the groove is machined.

The laser irradiation unit preferably has an objective lens that collects the laser beam, and the imaging unit preferably images the surface of the wafer through the objective lens. As a result, the focus of the laser irradiation unit and the imaging unit can be adjusted with a common objective lens, and the groove can be machined and the surface of the wafer can be imaged with the common objective lens.

It is preferable that the laser irradiation unit and the imaging unit can adjust the focus independently of each other. As a result, the groove can be machined and the surface of the wafer can be imaged by the laser irradiation unit and the image pickup unit whose focal points are adjusted respectively.

It is preferable that the acquisition unit acquires the positional deviation information at the same time as the groove is machined. As a result, the time for acquiring the misalignment information can be shortened.

One aspect of the wafer processing method for achieving the above object is to relatively move the first stage for holding the wafer in which the planned division line is formed on the surface and the laser irradiation unit for irradiating the surface of the wafer with laser light. By doing so, the grooving control step of machining a groove along the scheduled division line of the wafer by laser light and the misalignment information indicating the misalignment of the groove with respect to the scheduled division line are acquired by imaging the surface of the wafer. The acquisition process, the storage control step of associating the misalignment information with the unique information of the wafer and storing it in the storage unit, and the misalignment information associated with the unique information of the wafer in which the groove is formed are acquired from the storage unit. The groove is formed by relatively moving the second stage for holding the wafer in which the groove is formed and the blade for cutting the wafer in which the groove is formed based on the position information acquisition step to be performed and the acquired position deviation information. This is a wafer processing method including a cutting processing control step of cutting the formed wafer with a blade along a groove.

According to this aspect, the laser-machined groove can be appropriately bladed.

According to the present invention, the laser-machined groove can be appropriately bladed.

FIG. 1 is an overview view of a wafer processing system. FIG. 2 is a plan view of the wafer. FIG. 3 is a schematic view of the laser processing apparatus according to the first embodiment. FIG. 4 is a schematic view of a blade dicing device. FIG. 5 is a flowchart showing an example of processing of the wafer processing method. FIG. 6 is a diagram showing an example of a barcode attached to the wafer. FIG. 7 is a diagram showing an example of data stored in the database server. FIG. 8 is a schematic view of the laser processing apparatus according to the second embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, the X direction, the Y direction, and the Z direction are directions orthogonal to each other. Further, the X direction and the Y direction are horizontal directions, and the Z direction is a vertical direction.

<First Embodiment>
[Overall configuration of wafer processing system]
FIG. 1 is an overview view of the wafer processing system 10. The wafer processing system 10 includes a laser processing device 20, a blade dicing device 50, and a database server 60.

The laser processing device 20 is a device that performs laser processing on a work piece on which a laminated film including a metal film is formed on the surface. Here, the laser processing apparatus 20 irradiates the laser light which is the processing light along the street L of the wafer W in which the street L which is the planned division line is formed on the surface, and forms the groove C which is the processing groove (calf). Process. The blade dicing device 50 is a device that cuts an workpiece with a blade. Here, the blade dicing device 50 cuts the wafer W on which the groove C is formed.

The database server 60 corresponds to a storage unit for storing misalignment information, which will be described later, and includes a server function and a large-capacity storage. The laser processing device 20 and the database server 60, and the blade dicing device 50 and the database server 60 are connected to each other so as to be communicable via a network such as a P2P (Peer to Peer) connection. The database server 60 may be provided by the laser processing device 20 or the blade dicing device 50.

[Overall configuration of laser processing equipment]
FIG. 2 is a plan view of the wafer W. The wafer W is a laminate in which a Low-k film and a functional film forming a circuit are laminated on the surface of a substrate such as silicon. The wafer W is divided into a plurality of regions by a plurality of streets L arranged in a grid pattern in a direction intersecting each other. In Figure 2, the parallel streets in the X direction L _X, parallel streets in the Y direction is denoted by L _Y. Devices such as IC to the street L _X and the chip C are the respective regions partitioned by L _Y (Integrated Circuit) or LSI (Large Scale Integration) are formed.

FIG. 3 is a schematic view of the laser processing apparatus 20 according to the first embodiment. As shown in FIG. 3, the laser processing apparatus 20 includes a stage 22, a laser light source 24, a laser irradiation unit 26, a Z base 28 for a laser irradiation unit, a camera 30, a Z base 32 for a camera, a common base 34, and a moving mechanism 36. And a control device 38.

The stage 22 (an example of the first stage) holds the wafer W on the upper surface in a state where the surface of the wafer W faces upward in the Z direction. The stage 22 includes a motor (not shown), and is configured to be able to move in the X and Y directions and rotate in the XY plane by the moving mechanism 36.

The laser light source 24 includes a laser oscillator (not shown) and generates laser light which is processing light. The laser irradiation unit 26 irradiates the surface of the wafer W with laser light. The laser irradiation unit 26 includes an irradiation optical system (not shown) including an objective lens 26A, and the laser light generated by the laser light source 24 is converged and emitted by the irradiation optical system. The Z base 28 for the laser irradiation unit holds the laser irradiation unit 26 with the objective lens 26A of the laser irradiation unit 26 facing downward in the Z direction.

The camera 30 (an example of an imaging unit) includes an observation optical system (not shown) including a light source (not shown), an image sensor (not shown), and an objective lens 30A, and images (observes) the surface of the wafer W. The camera 30 includes a light source (not shown) equivalent to a 250 W metal halide light source, and can take an image with an exposure time of less than 1 [μs]. The objective lens 30A has a numerical aperture NA = 0.4 and a resolution = 0.8 [μm] at a wavelength of observation light of 550 [nm].

The camera Z base 32 holds the camera 30 with the objective lens 30A of the camera 30 facing downward in the Z direction. The common base 34 holds the Z base 28 for the laser irradiation unit and the Z base 32 for the camera.

In this way, the laser irradiation unit 26 and the camera 30 are held so that their focal points can be adjusted. Further, the common base 34 holds the camera 30 on the downstream side of the laser irradiation unit 26 with respect to the relative moving direction of the common base 34 and the stage 22 at the time of laser processing described later in the X direction.

The control device 38 controls the laser processing device 20 in an integrated manner. The laser processing apparatus 20 according to the control of the control unit 38, for processing a groove along the streets L _X and L _Y of the wafer W.

That is, the control device 38 generates a laser beam from the laser light source 24. Further, the control device 38 controls a motor (not shown) and moves the Z base 28 for the laser irradiation unit in the Z direction so that the focus of the objective lens 26A of the laser irradiation unit 26 is aligned with the desired Z direction position of the work W. Let me.

The control device 38 controls a motor (not shown) and moves the camera Z base 32 in the Z direction so that the focus of the objective lens 30A of the camera 30 is aligned with the desired Z direction position of the work W.

The control device 38 (an example of the grooving control unit) controls a motor (not shown), moves (scans) the common base 34 relative to the stage 22 in the X direction, and uses laser light to move (scan) the streets of the wafer W. along the L _X to remove Low-k film machining grooves. In the example shown in FIG. 3, the stage 22 is scanned to the left in the X direction with respect to the common base 34. Controller 38, the laser processing of one street L _X is finished, and controls the motor (not shown), after the stage 22 is moved in the Y direction relative to the common base 34, likewise next street L _X of Laser processing is performed.

In the present embodiment, the stage 22 is configured to be movable in the X and Y directions, and the laser irradiation unit 26 is configured to be movable in the Z direction. However, the stage 22 and the laser irradiation unit 26 are configured to be movable in the X and Y directions. It suffices if it can move relatively in the direction and the Z direction. For example, the stage 22 may be configured to be movable in the X direction, and the laser irradiation unit 26 may be configured to be movable in the Y and Z directions.

Further, the control unit 38, when the laser processing of all streets L _X completed, and controls the motor (not shown), the stage 22 is rotated 90 ° to the wafer W by rotating 90 °. Thereafter, as in the case of street L _X, the stage 22 is scanned in the X direction leftward relative to the common base 34, to process the grooves C along the streets L _Y of the wafer W by the laser beam.

The control device 38 (an example of an acquisition unit), by imaging the surface of the wafer W by the camera 30, observing the street L _X and L _Y and the groove C during processing of the groove C by the laser beam, Street L It acquires positional displacement information indicating a positional deviation of the groove C for the _X and L _Y. Further, the control device 38 (an example of the storage control unit) stores the acquired position shift information in the database server 60 in association with the unique information of the wafer W on which the groove C is formed.

[Overall configuration of blade dicing device]
The blade dicing device 50 is a device for processing the wafer W on which the groove C is formed by the laser processing device 20. FIG. 4 is a schematic view of the blade dicing device 50. As shown in FIG. 4, the blade dicing device 50 includes a stage 52, a blade 54, a moving mechanism 56, and a control device 58.

The stage 52 (an example of the second stage) holds the wafer W on the upper surface in a state where the surface of the wafer W faces upward in the Z direction. The stage 52 includes a motor (not shown), and is configured to be able to move in the X direction and rotate in the XY plane (movement in the θZ direction) by the moving mechanism 56. The blade 54 is a disk-shaped member parallel to the XZ plane provided with an annular cutting edge (not shown) on the outer circumference. The blade 54 is supported by a spindle (not shown) whose center of the disk is parallel in the Y direction. The spindle includes a motor (not shown), and is configured to be movable in the Y direction and the Z direction by the moving mechanism 56. The blade 54 includes a motor (not shown) connected to a spindle and is rotatably supported in the XZ plane.

The control device 58 controls the blade dicing device 50 in an integrated manner. The blade dicing device 50 cuts the wafer W according to the control of the control device 58.

That is, the control device 58 (an example of the position information acquisition unit) acquires the position deviation information corresponding to the wafer W to be processed from the database server 60. The control device 58 controls a motor (not shown) to rotate the blade 54. The control device 58 (an example of a cutting control unit) controls a motor (not shown), moves the stage 52 in the X direction while adjusting the machining position based on the acquired positional deviation information, and uses the blade 54 to move the stage 52 of the wafer W. the center of the groove cutting along the streets L _X. Controller 58, when cutting a center of the groove along one street L _X is finished, and controls the motor (not shown), after moving the blade 54 in the Y-direction, similarly to the street L _X next Cut the center of the groove along it.

Furthermore, the control device 58, when the cutting along all of the streets L _X completed, and controls the motor (not shown), the stage 52 is rotated 90 ° to the wafer W by rotating 90 °. Thereafter, as in the case of the groove along the streets L _X, it moves the stage 52 in the X direction while adjusting the processing position based on the acquired positional displacement information, along the streets L _Y of the wafer W by the blade 54 Cut the center of the groove.

In the present embodiment, the stage 52 is configured to be movable in the X direction and the θZ direction, and the blade 54 is configured to be movable in the Y direction and the Z direction. However, the stage 52 and the blade 54 are configured to be movable in the X direction and the Y direction. , Z direction, and θZ direction, for example, the stage 52 may be configured to be movable in the X direction, the Y direction, and the θZ direction, and the blade 54 may be configured to be movable in the Z direction.

[Wafer processing method]
FIG. 5 is a flowchart showing an example of processing of the wafer processing method. Here, the positions of all the streets L and the grooves C of the wafer W are inspected in advance, and blade dicing is performed based on the inspected information. Although another inspection device can be used for this inspection, here, in the laser machining process of the preceding laser machining device 20, the amount of deviation between the street L and the groove C is grasped at the same time as the laser machining, and the groove for each street L is grasped. Information on the amount of deviation of C is associated with the wafer W and passed to the subsequent blade dicing apparatus 50. The blade dicing device 50 processes the center of the groove C only by recognizing the pattern of the chip based on the deviation information.

In step S1 (an example of the grooving control process and an example of the acquisition process), the laser processing apparatus 20 performs grooving on the wafer W, and at the same time, observes the position of the groove C with respect to the street L, and observes the position of the groove C with respect to the street L. The amount of misalignment of C is inspected. When the laser processing apparatus 20 determines that the amount of misalignment between the street L and the groove C is large, the laser processing apparatus 20 corrects the position of the grooving process with respect to the adjacent street L by the next scan.

In this way, the laser processing apparatus 20 inspects during laser processing. Note that "simultaneous" here does not necessarily mean that the timings are exactly the same, but means that they are executed in parallel in one scan.

When the processing by the laser beam is stopped, the processing time increases. Therefore, in the present embodiment, a method is adopted in which the street L and the groove C are imaged during laser processing (during relative movement between the laser beam and the wafer W) and the amount of deviation thereof is inspected. This method is called a scan calf check. In this scan calf check, since the wafer W being scanned is imaged, a light source having a large amount of light and a processing device that continuously performs image processing are provided so that the street L and the groove C can be recognized even with a short exposure time. You will need it.

Here, the scanning speed of the grooving process is 600 [mm / sec]. According to the camera 30, the deviation in the Y direction can be suppressed to about 3 [μm].

The inspection of the amount of misalignment of the groove C may be performed on all streets L or on some streets L. If there is a street L for which the deviation amount of the groove C has not been inspected, the deviation amount of the position of the groove C with respect to the street L is generated by interpolation from the deviation amount of the position of the groove C with respect to the neighboring street L.

In step S2 (an example of the memory control step), in order to pass the misalignment information from the laser processing apparatus 20 to the blade dicing apparatus 50, the misalignment information recorded in step S1 is associated with the wafer W on which the groove C is formed to form a database. Stored in the server 60.

The association between the wafer W on which the groove C is formed and the misalignment information acquired from the wafer W is attached to the wafer ID (an example of wafer-specific information) engraved on the wafer W and the frame of the wafer W. This is done using the attached barcode (an example of wafer-specific information) as a key. FIG. 6 is a diagram showing an example of a barcode assigned to the wafer W. FIG. 6 shows a wafer W having a wafer ID of # 1 and a wafer W having a wafer ID of # 2. As shown in FIG. 6, each wafer W is given a unique barcode B on the back surface.

The laser processing apparatus 20 acquires the wafer ID of the wafer W on which the groove C is formed, associates the wafer ID with the misalignment information, and stores the wafer ID in the database server 60.

FIG. 7 is a diagram showing an example of misalignment information stored in the database server 60. In the example shown in FIG. 7, the deviation amounts of the grooves C with respect to the streets L of the wafer W having the wafer ID # 1 and the street numbers 1, 2, 3, 4, ... Are −0.5 μm, +1.0 μm, and +0, respectively. .1 μm, +0.1 μm, ... Further, the deviation amounts of the grooves C with respect to the streets L of the wafer W having the wafer ID # 2 and the street numbers 1, 2 ... Are −2.0 μm, −3.0 μm, ..., Respectively.

As described above, the amount of deviation of the groove C with respect to the street L can be stored in the database server 60 in association with the wafer ID of the wafer W on which the groove C is formed. Here, an example in which the wafer ID is managed by the barcode B has been described, but the wafer-specific information may be managed in the order of "what number of processed wafers".

In step S3 (an example of the position information acquisition process), the blade dicing apparatus 50 acquires the wafer ID of the wafer W to be processed, and acquires the position shift information of the wafer ID from the database server 60.

In step S4 (an example of a cutting process control process), the blade dicing apparatus 50 adjusts the cutting position with respect to the street L to be cut of the wafer W based on the acquired position deviation information. As a result, the blade dicing apparatus 50 cuts the center of the groove C of the wafer W without inspecting the position of the groove C of the wafer W to be machined.

Here, the association between the street L recognized by the laser processing apparatus 20 and the street L recognized by the blade dicing apparatus 50 is realized by pattern matching using a unique pattern such as a chip end or a notch of the wafer W.

For example, when the information of the wafer W is first registered in the laser processing apparatus 20 and the blade dicing apparatus 50, the information that the first street L is located at a place several μm away from the unique pattern is registered. The first street L can be aligned between the laser processing device 20 and the blade dicing device 50. In the case of the wafer W shown in FIG. 2, it has a unique pattern P in which a similar pattern does not exist in the adjacent region, and by defining the distance from the pattern P, the first street L can be obtained. It can be commonly recognized by the laser processing device 20 and the blade dicing device 50. As a unique pattern, features of the outer shape of the wafer W such as a notch and an orifra may be used.

Further, the position of the first street L may be aligned by setting the distance from the center of the wafer W to the first street L in advance and obtaining the center of the wafer W by using the outer shape measurement function.

As described above, according to the wafer processing method according to the present embodiment, the position of the groove C measured by the laser processing device 20 can be handed over to the blade dicing device 50, and the position of the groove C is again on the blade dicing device 50 side. It is possible to perform cutting without inspecting. As a result, high quality, high accuracy and short processing time are possible in the entire process.

In the blade dicing apparatus 50, it is theoretically possible to observe the groove C and acquire the misalignment information before cutting. However, the blade dicing device 50 has a lot of disturbance because it handles cutting water for cooling the blade, which is not preferable as a photographing environment. Therefore, the laser processing device 20 is preferable to the blade dicing device 50 because the position of the groove C can be observed in a stable environment.

In the present embodiment, the objective lens 26A of the laser irradiation unit 26 and the objective lens 30A of the camera 30 are independent of each other. Further, the laser irradiation unit Z base 28 and the camera Z base 32 are configured so that the laser irradiation unit 26 and the camera 30 can be individually moved in the Z direction. Therefore, there are no restrictions on the wavelength of the processed light, the depth of focus, the pupil diameter, the light emission during processing, the focus position during processing, and the like. Further, even when an optical system having a shallow depth of field is used, the laser irradiation unit 26 and the camera 30 can adjust their focal points independently of each other, so that both focus at an appropriate height. Therefore, processing and imaging can be performed under optimum conditions.

On the other hand, since the irradiation position of the laser irradiation unit 26 and the imaging position of the camera 30 are separated from each other, the scanning distance in the X direction is extended by the distance between them, and the processing time is long. Therefore, the inspection may be performed at an arbitrary timing, such as an interval of an arbitrary street L or before and after correction by laser processing, instead of the groove C for all the street L. The timing of implementation may be configured to be configurable by the user. Further, the deviation amount of the groove C that is not inspected may or may not be interpolated by a linear or arbitrary high-order curve.

Further, the Z base of the laser irradiation unit 26 and the camera 30 may be shared, and the laser irradiation unit 26 and the camera 30 may be configured to be movable in the Z direction at the same time.

Further, instead of the database server 60, a portable storage medium such as a USB (Universal Serial Bus) memory may be used. In this case, the laser processing device 20 and the blade dicing device 50 are respectively configured to enable data access to the portable storage medium.

<Second embodiment>
FIG. 8 is a schematic view of the laser processing apparatus 70 according to the second embodiment. The same reference numerals are given to the parts common to the laser processing apparatus 20, and detailed description thereof will be omitted. As shown in FIG. 8, the laser processing apparatus 20 includes a laser irradiation unit 72, a dichroic mirror 74, and a common Z base 76.

The laser irradiation unit 72 includes an objective lens 72A. The dichroic mirror 74 is arranged in the optical path of the laser beam from the laser light source 24 to the objective lens 72A. The common Z base 76 holds the laser irradiation unit 72 with the objective lens 72A of the laser irradiation unit 72 facing downward in the Z direction.

The laser light emitted from the laser light source 24 passes through the dichroic mirror 74 and enters the objective lens 72A of the laser irradiation unit 72. The objective lens 72A collects the incident laser light at the focal position of the wafer W.

Further, the common Z base 76 holds the camera 30. The camera 30 includes an observation light source 30B, a half mirror 30C, and an image sensor 30D. The observation light emitted from the observation light source 30B is reflected by the half mirror 30C and the dichroic mirror 74, and is incident on the objective lens 72A. The objective lens 72A causes the incident observation light to be incident on the focal position of the wafer W.

Of the observation light incident on the wafer W, a part of the reflected light reflected by the wafer W is incident on the objective lens 72A as the subject light. The subject light incident on the objective lens 72A is reflected by the dichroic mirror 74 and incident on the camera 30, passes through the half mirror 30C, and is incident on the image sensor 30D. The image sensor 30D receives the incident subject light and images the subject image.

In this way, the camera 30 images the surface of the wafer W in which the groove C is formed through the objective lens 72A of the laser irradiation unit 72. Since it is a single objective lens 72A, the entire optical system can be made compact. Further, the common Z base 76 can simultaneously focus the processing light and the observation light. Further, the scanning distance at the time of processing can be shortened. An optical system may be added so that the focal point of the processing light and the focal point of the observation light can be adjusted independently of each other.

The single objective lens 72A has lower contrast and resolving power than the dedicated objective lens 30A (see FIG. 3) of the camera 30. Specifically, the objective lens 72A has a numerical aperture of NA = 0.15 and a resolution of about 1.7 [μm], assuming that the wavelength of the observation light is 430 [nm].

<Others>
According to the laser machining apparatus 20 and the laser machining apparatus 70, the position in the Y direction during machining is adjusted (active Y) or the angle is adjusted in real time in the direction of canceling the deviation amount of the groove C shown in FIG. 7 (active Y). It is also possible to use the amount of deviation of the groove C for feedback, such as active θ).

If the amount of misalignment at a certain speed in the X direction at a certain Y coordinate is reproducible, once the amount of misalignment is observed and stored under that condition, then in real time when processing under the same conditions. No need to inspect. However, if there is a disturbance such as a change in water temperature or air temperature, a method of measuring and correcting in real time is effective. The advantages of not inspecting in real time are that the inspection interval is not affected by the processing speed, so fine sampling is possible, and the processing time does not affect the processing speed, so there is a margin in processing capacity. It can be mentioned that the problem does not occur even with a device having a low speed.

Further, the soundness of the nozzle may be inspected from the amount of debris generated by observing the amount of debris generated by the camera 30.

If the grooves C for all the streets L of the wafer W can be observed without gaps, the appearance of the grooves C of all the chips will be inspected in the laser processing apparatus 20 (70), so that processing defects and processing omissions will occur. It is possible to grasp in advance which defective chips are being used. Further, by measuring the change in the distortion, it is possible to measure the failure prediction and the maintenance timing of the laser processing apparatus 20 (70).

The technical scope of the present invention is not limited to the scope described in the above embodiments. The configurations and the like in each embodiment can be appropriately combined between the respective embodiments without departing from the spirit of the present invention.

10 ... Wafer processing system 20 ... Laser processing device 22 ... Stage 24 ... Laser light source 26 ... Laser irradiation unit 26A ... Objective lens 28 ... Z base for laser irradiation unit 30 ... Camera 30A ... Objective lens 32 ... Z base for camera 34 ... Common Base 36 ... Moving mechanism 38 ... Control device 50 ... Blade dicing device 52 ... Stage 54 ... Blade 56 ... Moving mechanism 58 ... Control device 60 ... Database server 70 ... Laser processing device 72 ... Laser irradiation unit 72A ... Objective lens 74 ... Dycroic mirror 76 ... each step of common Z base B ... barcode C ... groove _L, L _X, L Y _... Street P ... pattern W ... wafer S1 to S4 ... wafer processing method

Claims (6)

A wafer processing system including a laser processing device, a blade dicing device, and a storage unit.
The laser processing device is
The first stage, which holds the wafer with the planned division line formed on the surface, and
A laser irradiation unit that irradiates the surface of the wafer with laser light,
By moving the first stage and the laser irradiation unit relative to each other, a grooving processing control unit that processes a groove by the laser beam along the planned division line of the wafer and a grooving processing control unit.
An acquisition unit that acquires positional deviation information indicating the positional deviation of the groove with respect to the planned division line by imaging the surface of the wafer with the imaging unit.
A storage control unit that associates the misalignment information with the unique information of the wafer and stores it in the storage unit.
With
The blade dicing apparatus targets the wafer in which the groove is formed by the laser processing apparatus as a processing target.
The blade dicing device is
A position information acquisition unit that acquires the position deviation information corresponding to the wafer from the storage unit, and
A second stage for holding the wafer and
A blade that cuts the wafer and
A cutting control unit that cuts the wafer along the groove by the blade by relatively moving the second stage and the blade based on the acquired misalignment information.
Wafer processing system equipped with. The wafer processing system according to claim 1, wherein the imaging unit is arranged on the downstream side of the laser irradiation unit with respect to the relative moving directions of the first stage and the laser irradiation unit. The laser irradiation unit has an objective lens that collects the laser beam.
The wafer processing system according to claim 1 or 2, wherein the image pickup unit images the surface of the wafer through the objective lens. The wafer processing system according to any one of claims 1 to 3, wherein the laser irradiation unit and the imaging unit can adjust their focal points independently of each other. The wafer processing system according to any one of claims 1 to 4, wherein the acquisition unit acquires the misalignment information at the same time as processing the groove. By relatively moving the first stage for holding the wafer having the planned division line formed on the surface and the laser irradiation unit for irradiating the surface of the wafer with the laser beam, the above-mentioned is performed along the planned division line of the wafer. Grooving control process for machining grooves with laser light and
An acquisition step of acquiring position shift information indicating the position shift of the groove with respect to the planned division line by imaging the surface of the wafer, and
A storage control step of associating the misalignment information with the unique information of the wafer and storing it in the storage unit,
A position information acquisition step of acquiring the position deviation information associated with the unique information of the wafer on which the groove is formed from the storage unit, and
The groove was formed by relatively moving the second stage for holding the wafer in which the groove was formed and the blade for cutting the wafer in which the groove was formed based on the acquired misalignment information. A cutting control process in which the wafer is cut along the groove by the blade, and
Wafer processing method including.

Images