JP5491273B2 - Wafer chamfering device - Google Patents

Description

  The present invention relates to a wafer chamfering apparatus that performs chamfering processing on the outer periphery of a wafer such as silicon used as a material of a semiconductor element.

  Disc-like thin plate materials used as substrates for integrated circuits such as various crystal wafers and other semiconductor device wafers, and other disc-like thin plate materials made of hard materials including metal materials, such as silicon (Si) single crystal, gallium arsenide (GaAs), Quartz, quartz, sapphire, ferrite, silicon carbide (SiC), etc. (collectively these are simply referred to as wafers) are thinly cut out from an ingot by a slicing machine, and then the edges (peripheries) are ground. And chamfered to a predetermined shape and a predetermined surface roughness.

  As shown in FIG. 13, a V-shaped or U-shaped notch 1n for indicating a reference position in the circumferential direction is formed on the wafer 1 to be chamfered, and this is also chamfered. .

As shown in FIG. 14, the edge 1a of the wafer 1 has an upper slope 1au inclined by an angle α1 (about 22 °) with respect to the upper plane and a lower angle inclined by an angle α1 (about 22 °) with respect to the lower plane. There is a case where the cross section is formed into a cross-sectional shape (a substantially triangular shape as a whole) including the inclined surface 1ad and an arc 1c having a radius R1 that smoothly connects the inclined surface 1ad.
In this case, the horizontal length of the upper slope 1au is referred to as “chamfer width X1”, and the horizontal length of the lower slope 1ad is referred to as “chamfer width X2”.
Further, as shown in FIG. 15, the edge 1a of the wafer 1 has an upper slope 1au inclined by an angle α2 with respect to the upper plane, a lower slope 1ad inclined by an angle α2 with respect to the lower plane, and an end face of the edge 1a. A circular peripheral surface 1b that forms a straight line, and two circular arcs having the same radius R2 that smoothly connect between the upper inclined surface 1au and the peripheral end surface 1b and between the lower inclined surface 1ad and the peripheral end surface 1b, It may be processed into a cross-sectional shape (substantially trapezoidal shape) consisting of 1c.
Also in this case, the horizontal length of the upper slope 1au is referred to as “chamfer width X1”, the horizontal length of the lower slope 1ad is referred to as “chamfer width X2”, and the length of the face width of the peripheral edge 1b is referred to as “chamfer width X3”. .

The conventional chamfering apparatus is provided with one processing section 40 having one processing table 41 on which the wafer 1 is placed and grindstones 42 and 43 for chamfering the wafer 1 (see FIGS. 16 and 17). ).
The chamfering apparatus includes, in addition to the processing unit 40, two cassettes 12 for storing the wafer 1 before processing, the thickness of the wafer 1 before processing, and the center of the wafer 1 and the notch 1n. A pre-setting unit 45 for setting the direction (circumferential direction of the wafer), a cleaning unit 47 for cleaning the processed wafer 1, a post-measurement unit 50 for measuring the shape dimension of the processed wafer, and a processed wafer 1 and a cassette 13 for storing 1.

  In this chamfering apparatus, the wafer 1 taken out from the cassette 12 by the carry-in arm 48 on which the wafer 1 can be loaded and conveyed is conveyed to the pre-setting unit 45, where the thickness is measured and the circumferential direction is roughly set. Next, the wafer 1 is transferred to the upper part of the processing table 41 by the loading arm 48 and transferred from the loading arm 48 to the processing and conveying unit 44. The processing conveyance unit 44 supports the wafer 1 with two rollers and one positioning piece, and can move up and down. The center of the wafer 1 and the center of the processing table 41 coincide with each other, and the circumference of the wafer 1 The direction position is accurately positioned and placed on the processing table 41.

The processing unit 40 had a grindstone 42 for grinding the edge 1a of the circumferential portion of the wafer 1 and a grindstone 43 for grinding the notch 1n. The processing unit 40 may be provided with two types of coarse grinding and fine grinding for each of the edge grindstone 42 and the notch grindstone 43. The wafer 1 is adsorbed and fixed to the processing table 41 with a negative pressure or the like, rotates along with the processing table 41, and the edge 1 a is chamfered by pressing the rotating grindstone 42.
Further, the grindstone 43 is pressed against the notch 1n of the wafer 1 while the processing table 41 is stationary, and chamfering is performed.

  The processed wafer 1 is sandwiched by a cleaning transfer unit 46 having four rollers, transferred from the processing table 41 to the cleaning unit 47, and cleaned by the cleaning unit 47. Next, the wafer 1 is transferred from the cleaning unit 47 to the post-measurement unit 50 by the cleaning transfer unit 46. The wafer 1 whose shape and dimensions have been measured by the post-measurement unit 50 is placed on the carry-out arm 49, transferred to the cassette 13, and stored.

In such a conventional wafer chamfering apparatus, the time for taking out the wafer 1 from the cassette 12, the time for setting the circumferential position of the wafer 1 before processing, and the time for chamfering the wafer 1 by the processing unit 40 were processed. Comparing the time for cleaning the wafer 1, the time for measuring the shape and dimension of the cleaned wafer 1, and the time for storing the processed wafer 1 in the cassette 13, the chamfering time is generally the longest.
Therefore, the throughput (processing amount per unit time) of the wafer chamfering apparatus is affected by the length of the chamfering process.

Therefore, Patent Document 1 describes a wafer chamfering apparatus in which a plurality of processing units are provided to improve throughput. 16 and 17 are cited from FIGS. 1 and 2 of Patent Document 1. FIG.
This chamfering apparatus has a plurality of processing units 40, and each processing unit 40 includes a processing table 41 and units of grindstones 42 and 43 having different processing characteristics (wafer processing locations, roughness, etc.). .
Further, the processing / conveying unit 44 has a movable range in which the wafer 1 can be supplied from the pre-setting unit 45 to each processing unit 40. Similarly, the cleaning / conveying unit 46 can also transport the wafer 1 from each processing unit 40 to the cleaning unit 47. It has a movable range.
Other configurations are substantially the same as those of the conventional chamfering apparatus.

In this chamfering apparatus, the wafer 1 whose thickness is measured by the pre-setting unit 45 and whose circumferential position is roughly set is transferred to the processing unit 40 by the carry-in arm 48 and the processing transfer unit 44, and is chamfered. The next wafer 1 that has been measured and set by the previous setting unit 45 while the previous wafer 1 is chamfered by the processing unit 40 is transferred to another processing unit 40 by the carry-in arm 48 and the processing transfer unit 44. Carried in and chamfered.
As described above, in the chamfering apparatus of Patent Document 1, the wafers 1 are sequentially supplied to the plurality of processing units 40, and the wafers 1 are chamfered in parallel by the plurality of processing units 40, and the processed wafers 1 are sequentially processed. By transporting to the cleaning unit 47, the throughput could be increased.

  In addition, as another chamfering device, a disk-shaped resin bond grindstone or rubber that is rotated after rough grinding is performed on a single wafer with a grindstone with grooves that match the required cross-sectional shape of the wafer. There were some which were precisely ground with a grindstone to improve chamfering accuracy and surface roughness (Patent Documents 2 and 3).

JP-A-8-150551 JP 2001-300837 A JP 2008-177348 A

However, in the chamfering device of Patent Document 1, a plurality of processing units 40 are installed, and each processing unit 40 is provided with a set of a plurality of types of grindstones 42 and 43. It is necessary to provide a number of grindstones obtained by multiplying the number of types of grindstones 42 and 43 and a device for precisely moving the position of the grindstone, which increases the cost and size of the device.
Further, since the entire chamfering apparatus has a plurality of grindstones having the same processing characteristics (for example, the grindstone 42), the quality of the wafer 1 varies when the degree of wear differs between the grindstones 42 having the same processing characteristics. In addition, it took time and effort to manage the plurality of grindstones 42. For example, when exchanging one grindstone 42, machining finish dimensions such as diameter and chamfering width are input so that chamfering accuracy does not vary with the grindstone 42 having the same machining characteristics of the other machining unit 40. It was necessary to adjust the setting of the control unit.
Further, once the chamfering process is started, the spindle motor that rotates the grindstones 42 and 43 normally keeps operating even when the grindstones 42 and 43 are not processing the wafer 1. As a result, the amount of waste of electric power and cooling water has increased, leading to an increase in running cost.

The present invention has been made in order to solve the above-described problems, and chamfering a wafer in parallel with a plurality of processing tables to improve throughput and reduce the total number of grindstones, thereby reducing the cost and size of the entire apparatus. It is an object of the present invention to provide a wafer chamfering apparatus which can be reduced and easily maintained.
Another problem is that when chamfering a single wafer, most of the processing before chamfering, chamfering, and processing after chamfering can be performed on one processing table and its vicinity. An object of the present invention is to provide a wafer chamfering apparatus capable of reducing the overall cost and size.

In the present invention, means for solving the above problems are as follows.
A wafer chamfering apparatus according to a first invention includes a plurality of processing tables for placing a wafer and a plurality of grindstones having different processing characteristics respectively corresponding to a plurality of types of processing steps for chamfering the peripheral edge of the wafer. And a grindstone moving means for moving the grindstones between the processing tables. The grindstones chamfer the wafer by approaching one processing table, and then sequentially move to the other processing tables. Then, the plurality of wafers are chamfered in parallel by the plurality of grindstones by repeating the processing.

  In the wafer chamfering apparatus according to the second invention, when the grindstone moving means chamfers the wafer placed on the processing table, the position of the grindstone is precisely moved in the moving direction between the processing tables. It is characterized by that.

A wafer chamfering apparatus according to a third aspect of the invention detects a plurality of processing tables for placing a wafer, a grindstone for chamfering the peripheral end surface of the wafer, and a wafer shape or placement position before chamfering the wafer. Therefore, the pre-processing sensor has at least one pre-processing sensor for measuring different measurement objects and a pre-processing sensor moving means for moving the pre-processing sensor between the processing tables. The shape or placement position of the wafer is detected at a position held above the processing table or a position placed on each processing table.
Examples of the measurement target of the pre-processing sensor include the diameter, thickness, center position, and notch position of the wafer.
When the chamfering apparatus has a plurality of the pre-processing sensors, the pre-processing sensor moving means may be provided for each pre-processing sensor, and a unit for moving several pre-processing sensors by one pre-processing sensor moving means. You may form as.

A wafer chamfering apparatus according to a fourth aspect of the present invention includes a plurality of processing tables for placing a wafer, a grindstone for chamfering the peripheral end surface of the wafer, and a shape of the wafer after chamfering the wafer. One or more post-processing sensors for measuring different measurement objects, and post-processing sensor moving means for moving the post-processing sensors between the processing tables, wherein the post-processing sensor is configured to transfer the wafer to each processing table. The shape of the wafer is measured at a position held above or a position placed on each processing table.
When the chamfering device has a plurality of post-processing sensors, the post-processing sensor moving means may be provided for each post-processing sensor, or several post-processing sensors are integrated into one post-processing sensor movement. You may form so that it may move by a means.

A wafer chamfering apparatus according to a fifth invention includes a plurality of processing tables for placing a wafer, a grindstone for chamfering the peripheral end surface of the wafer, a wafer cleaning mechanism for cleaning the wafer after chamfering the wafer, A wafer drying mechanism for drying the wafer after cleaning, and a post-processing mechanism moving means for moving the wafer cleaning mechanism and the wafer drying mechanism between the processing tables. The wafer is washed or dried at a position where the wafer is held above each processing table or a position where the wafer is placed on each processing table.
In such a chamfering apparatus, the wafer cleaning mechanism and the wafer drying mechanism may be provided with different post-processing mechanism moving means, and the wafer cleaning mechanism and the wafer drying mechanism are moved by one post-processing mechanism moving means. It may be formed as a unit.

  In a sixth aspect of the invention, the wafer is held above the processing table and cleaned by the wafer cleaning mechanism, and at the same time the processing table is cleaned, and then the wafer is dried by the wafer drying mechanism and at the same time the processing table is dried. It is characterized by making it.

  In a seventh aspect of the present invention, any of the pre-processing sensor, the post-processing sensor, the wafer cleaning mechanism, or the wafer drying mechanism is provided between a cassette for storing the wafer before and after chamfering and each processing table. And provided on an arm for transporting the wafer.

  The eighth invention is characterized in that the plurality of processing tables are arranged linearly.

  According to a ninth aspect of the present invention, the processing table is moved in a horizontal orthogonal direction with respect to any of the movement directions of the grindstone moving means, the pre-processing sensor moving means, the post-processing sensor moving means, or the post-processing mechanism moving means. A processing table approaching / separating means and a processing table rotating means for rotating the processing table are provided.

According to the first invention, a plurality of processing tables for placing a wafer, a plurality of grindstones having different processing characteristics respectively corresponding to a plurality of types of processing steps for chamfering the peripheral edge of the wafer, And a grindstone moving means for moving the grindstone between the processing tables. The grindstones each approach the one processing table to chamfer the wafer, and then sequentially move to another processing table for processing. By repeating this, the plurality of wafers can be chamfered in parallel by the plurality of grindstones, thereby increasing the throughput of the chamfering apparatus. Moreover, since the number of grindstones in the entire chamfering device can be suppressed, the cost of the grindstone can be reduced and the management burden of the grindstone can be reduced.
Further, in the chamfering apparatus, it is necessary to continue to rotate the grindstone even during play time when the wafer is not chamfered and to use cooling water for the spindle motor. In the chamfering apparatus according to the first invention, the number of grindstones is required. Since the time of play of each grindstone is reduced and waste of electric power and cooling water can be reduced.

  According to the second invention, when the grindstone moving means chamfers the wafer placed on the processing table, the position of the grindstone is precisely moved in the moving direction between the processing tables, so that 1 One grindstone moving means can serve as both a large movement between processing tables and a precise movement at the time of chamfering a wafer, and the cost of the grindstone moving means in the chamfering apparatus can be reduced.

  According to the third aspect of the present invention, one or more pre-processing sensors for measuring different measurement objects to detect the shape or placement position of the wafer before chamfering the wafer, and the pre-processing sensor between the processing tables. And a pre-processing sensor moving means for moving the wafer at a position where the pre-processing sensor holds the wafer above each processing table or a position on each processing table. By detecting this, it is not necessary to provide an independent space for the measurement before chamfering, so that the chamfering device can be saved and the throughput can be improved by omitting the time required for moving the wafer.

  According to the fourth aspect of the present invention, one or more post-processing sensors that measure different measurement objects to detect the shape of the wafer after chamfering the wafer, and post-processing that moves the post-processing sensor between the processing tables. A sensor moving means, and the post-processing sensor measures the shape of the wafer at a position where the wafer is held above each processing table or placed on each processing table. Since it is not necessary to provide an independent space for the measurement, the chamfering device can be saved, and the time required for moving the wafer can be omitted to improve the throughput.

  According to the fifth invention, a wafer cleaning mechanism for cleaning the wafer after chamfering the wafer, a wafer drying mechanism for drying the wafer after cleaning, and the wafer cleaning mechanism and the wafer drying mechanism are moved between the processing tables. And a post-processing mechanism moving means, wherein the wafer cleaning mechanism or the wafer drying mechanism cleans or dries the wafer at a position where the wafer is held above each processing table or placed on each processing table. Accordingly, it is not necessary to provide an independent space for cleaning and drying, so that the chamfering device can be saved in space and the throughput can be improved by omitting the time required for moving the wafer. In addition, since there is no need to move the wafer from the vicinity of the processing table before cleaning, dirt is not scattered around by the movement.

  According to a sixth aspect of the invention, the wafer is held above the processing table and cleaned by the wafer cleaning mechanism, and at the same time the processing table is cleaned, and then the wafer is dried by the wafer drying mechanism and at the same time the processing table. By drying the substrate, it is not necessary to provide a special time for cleaning and drying the processing table, and sufficient cleaning and drying time can be secured and the throughput of the chamfering processing apparatus can be improved.

  According to the seventh invention, any one of the pre-processing sensor, the post-processing sensor, the wafer cleaning mechanism, or the wafer drying mechanism is provided with a cassette for storing the wafer before and after chamfering, and each processing table. By providing the arm for transferring the wafer between the two, this arm also serves as a pre-processing sensor moving means, a post-processing sensor moving means, or a post-processing mechanism moving means, and reduces the cost of the entire chamfering apparatus. In addition, space can be saved.

  According to the eighth invention, the plurality of processing tables are arranged in a straight line, whereby a chamfering device with little dead space can be obtained.

  According to the ninth invention, the processing table is arranged in a direction perpendicular to the moving direction of any one of the grinding wheel moving means, the pre-processing sensor moving means, the post-processing sensor moving means, or the post-processing mechanism moving means. By providing a processing table approaching / separating means for moving and a processing table rotating means for rotating the processing table, the processing table is moved closer to and away from a grindstone as necessary, so that the wafer has a desired cross-sectional shape. The chamfering process can be performed and the processing table can be rotated to chamfer the entire periphery and notch of the wafer edge.

It is a plane explanatory view showing a chamfering device of a wafer concerning an embodiment of the present invention. It is front explanatory drawing which shows the same chamfering apparatus. It is a figure which shows a carrying-in arm, (a) is plane explanatory drawing, (b) is front explanatory drawing. It is side explanatory drawing which shows the chamfering process using an edge rough grindstone. It is a perspective explanatory view showing a rough grinding wheel support device of an edge rough grinding wheel and a notch rough grinding wheel. It is an isometric view enlarged view which shows the chamfering process using an edge fine grinding wheel. It is a front view which shows the grindstone support apparatus of an edge fine grinding grindstone. It is a side view which shows the grindstone support apparatus of an edge fine grinding grindstone. It is front explanatory drawing which shows the other chamfering process using an edge fine grinding wheel. It is a perspective view which shows the grindstone support apparatus of a notch fine grinding wheel. It is a figure which shows a carrying-out arm, (a) is plane explanatory drawing, (b) is front explanatory drawing. It is a timing chart at the time of chamfering a wafer with a chamfering apparatus. It is a figure which shows the planar shape of a wafer. It is a figure which shows the cross-sectional shape of the wafer by a chamfering process. It is a figure which shows the cross-sectional shape of the other wafer by a chamfering process. It is plane explanatory drawing which shows the chamfering apparatus of patent document 1. FIG. It is a perspective explanatory view showing a chamfering device of Patent Document 1.

Hereinafter, a wafer chamfering apparatus according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, this chamfering apparatus has a plurality of processing tables 2 on which a wafer 1 is placed, and has different processing characteristics (roughness, processing points of wafers, etc.) corresponding to a plurality of chamfering processes. A plurality of grindstones 3, 4, 5, 6 are provided, and each grindstone 3, 4, 5, 6 is movable between the processing tables 2.
Similarly, the sensors 7, 8 and 9, the cleaning mechanism 10, and the drying mechanism 11 that measure, clean, and dry the wafer 1 before and after the chamfering process are movable between the processing tables 2. .
This will be described in detail below.

As shown in FIG. 1, this chamfering apparatus includes two cassettes 12 and 12 for storing an unprocessed wafer 1 and four processing tables 2 (2A to 2D) for chamfering by placing the wafer 1 thereon. And two cassettes 13 and 13 for storing processed wafers 1.
Further, the chamfering apparatus takes out the wafer 1 from the cassette 12 or stores it in the cassette 13 for transporting the wafer 1, and receives the wafer 1 from the cassette arm 14 and places it on each processing table 2. And a carry-out arm 16 for delivering the processed wafer 1 from the processing table 2 to the cassette arm 14.
For the chamfering of the wafer 1, this chamfering device includes a rough grinding wheel 3 for rough polishing of the edge 1a, a pair of disk grinding stones 4a, 4a for contouring processing (fine polishing) of the edge 1a, and a notch 1n. A rough grinding wheel 5 for rough grinding and a grinding wheel 6 for fine grinding with a notch 1n.

As shown in FIG. 1, the four processing tables 2 are arranged in series on a substantially straight line. Hereinafter, this arrangement direction is referred to as an X-axis direction.
As shown in FIG. 2, a stage 17 on which the wafer 1 is placed is provided on the processing table 2. This stage 17 has a smaller diameter than the wafer 1 and has a suction chuck for fixing the placed wafer 1 with a negative pressure.
As shown in FIGS. 2 and 7, the processing table 2 is provided with a processing table rotating mechanism 18 using a motor, and the stage 17 is rotated during the chamfering processing of the wafer 1 so that the edge of the wafer 1 is rotated. 1a can be chamfered over the entire circumference. Further, the processing table 2 can be moved in a horizontal direction orthogonal to the X axis (hereinafter referred to as the Y axis direction) by a processing table approaching / separating mechanism 19 constituted by rails, ball screws, or the like. Chamfering can be performed by approaching and separating from each of the grinding wheels 3, 4, 5, 6.

As shown in FIG. 1, a cassette 12 for storing unprocessed wafers 1 and a cassette 13 for storing processed wafers 1 are also arranged along the X-axis direction.
A cassette arm 14 is provided between the rows of the cassettes 12 and 13 and the row of the processing table 2. The cassette arm 14 has a substantially Y-shaped arm portion 14a for carrying the wafer 1 thereon. Further, as shown in FIG. 2, the cassette arm 14 is provided with a cassette arm X-axis moving mechanism 20 for moving in the X-axis direction, and a cassette arm Y for moving the arm portion 14a in the Y-axis direction. An axis moving mechanism 21, a cassette arm raising / lowering mechanism 22 that moves up and down, and a cassette arm turning mechanism 23 that turns horizontally are provided.

As shown in FIGS. 2 and 3, the carry-in arm 15 is hung from the ceiling side in the vicinity of the processing table 2, and has an arm portion 15a protruding in the horizontal direction. An adsorption chuck 15b that adsorbs the wafer from above by pressure is provided, and the wafer 1 can be held. A direct drive motor 15c is provided immediately above the suction chuck 15b, and the held wafer 1 can be rotated in the circumferential direction to be measured and placed as described later.
The carry-in arm 15 is provided with a carry-in arm moving mechanism 24 (FIG. 2) for moving in the X-axis direction and a carry-in arm raising / lowering mechanism (not shown) for raising and lowering the arm portion 15a. The unprocessed wafer 1 can be transferred to the processing table 2.

In addition, an alignment sensor 7 that measures the diameter (D in FIG. 13) or the radius (same R), the center, and the position of the notch 1n of the wafer 1 in a pair of upper and lower sides at approximately the same height as the arm portion 15a. (The alignment sensor 7 is omitted in FIG. 2).
As shown in FIG. 3, since the alignment sensor 7 is pivotably attached to the loading arm 15, when the wafer 1 is sucked or removed from the suction chuck 15 b, the alignment sensor 7 can be released so as not to come in contact with it. The wafer 1 can be measured by turning the alignment sensor 7 up and down the wafer 1 while the loading arm 15 holds the wafer 1. In addition, an alignment sensor elevating mechanism (not shown) for elevating the alignment sensor 7 with respect to the loading arm 15 is provided, and the height of the alignment sensor 7 can be adjusted when measuring the wafer 1.
The carry-in arm 15 rotates the wafer 1 based on the circumferential placement angle of the wafer 1 set from the measurement result of the alignment sensor 7 and places it on the processing table 2 at a desired placement angle. At this time, the center of the wafer 1 coincides with the center of the stage 17 of the processing table 2.

Further, the carry-in arm 15 is provided with a pair of upper and lower thickness sensors 8 below the arm portion 15a. After the wafer 1 is placed on the processing table 2, the heights of the upper and lower surfaces of the wafer 1 are measured. The thickness of the wafer 1 is detected from the difference.
Note that the thickness sensor 8 may be configured to measure the thickness of the wafer 1 while the carry-in arm 15 holds the wafer 1.

As shown in FIGS. 4 and 5, the edge roughing grindstone 3 is a horizontal general-purpose grindstone in which grooves corresponding to the required cross-sectional shape of the wafer 1 are formed on the peripheral end surface. The processing table 2 is moved in the Y-axis direction by the processing table approaching / separating mechanism 19 while rotating at different rotational speeds in the opposite directions, and the edge 1a of the wafer 1 is pressed against the grindstone groove to roughen the edge 1a. I do.
As shown in FIG. 5, the notch roughing grindstone 5 is a general grindstone in which grooves corresponding to the required cross-sectional shape of the wafer 1 are formed on the peripheral end surface in the same manner as the edge roughing grindstone 3. The Y-axis direction movement of the machining table 2 by the machining table approaching / separating mechanism 19 and the X-axis direction movement of the notch coarse grinding wheel by the coarse grinding wheel moving mechanism 27 described later while rotating in the same direction as the edge roughing grinding wheel 3 Is used for roughing along the shape of the notch 1n.
As shown in FIGS. 2 and 5, the edge roughening grindstone 3 and the notch roughening grindstone 5 are attached to one grindstone support device 26 to chamfer the wafer 1. The grindstone support device 26 is attached to the upper part of the side wall 29 of the chamfering device, and has a rough grindstone moving mechanism 27 for moving in the X-axis direction and a rough grindstone lifting mechanism 28 for moving up and down. As an example, the rough grinding wheel moving mechanism 27 can be configured by using a ball screw including a screw shaft in the X-axis direction attached to the side wall 29 and a nut attached to the grinding wheel support device 26 as a driving force. it can. Similarly, the rough grinding stone lifting mechanism 28 can also be configured using a ball screw.

As shown in FIG. 6, the edge fine grinding wheel 4 is composed of a pair of vertical disk-shaped grinding wheels 4 a and 4 a that face each other in the vicinity, and rotate horizontally by rotating each of them vertically and in opposite directions. The chamfering process of the edge 1a is performed by pressing against the wafer 1 to be performed.
Therefore, as shown in FIGS. 2, 7, and 8, the edge polishing wheel 4 is supported by the wheel support device 30, and each of the wheels 4a and 4a is attached to the wheel support device 30 via a spindle motor that rotates the wheel. It is attached. Moreover, while providing the support apparatus raising / lowering mechanism 31 which raises / lowers the grindstone support apparatus 30 whole, the edge precise grinding stone raising / lowering mechanisms 32 and 32 which raise / lower each grindstone 4a, 4a separately are provided, and each grindstone 4a, 4a is the same. The edge 1a of the wafer 1 can be chamfered while maintaining the height (FIG. 6). However, the upper and lower slopes 1au and 1au are arranged so that the wafers 1 are sandwiched from above and below by varying the heights of the grindstones 4a and 4a. It is possible to chamfer 1ad (FIG. 9).
As shown in FIG. 2, the grindstone support device 30 for attaching the edge fine grinding stone 4 is assembled to the lower portion of the side wall 29 of the chamfering device, and has an edge fine grinding stone moving mechanism 33 for moving in the X-axis direction. Yes. As an example, the edge precision grinding wheel moving mechanism 33 is configured by using a ball screw including a screw shaft in the X-axis direction attached to the side wall 29 and a nut attached to the grinding wheel support device 30 as a driving force. Can do.

As shown in FIG. 10, the notch fine grinding wheel 6 is a thin disc-shaped grinding wheel formed of rubber containing an abrasive, and is installed vertically and is moved vertically close to the processing table while being rotated in the vertical direction. Using the movement of the machining table 2 in the Y-axis direction by the mechanism 19 and the movement of the notch fine grinding wheel 6 in the X-axis direction by a notch fine grinding wheel moving mechanism 35 described later, precise grinding is performed along the shape of the notch 1n. Do.
As shown in FIG. 10, the notch fine grinding wheel 6 is supported by a grinding wheel support device 34, and is attached so as to rotate in the vertical direction by converting the rotation of a spindle motor that rotates the grinding wheel at a tip end portion 34a. .
As shown in FIGS. 2 and 10, the grindstone support device 34 for attaching the notch fine grinding wheel 6 is attached to the lower portion of the middle wall 37 of the chamfering device installed between the processing table 2 and the cassettes 12 and 13. And a notch fine grinding wheel moving mechanism 35 for moving in the X-axis direction and a notch fine grinding wheel lifting mechanism 36 for lifting and lowering. As an example, the notch precision grinding wheel moving mechanism 35 uses a ball screw including a screw shaft in the X-axis direction attached to the inner wall 37 and a nut attached to the grinding wheel support device 34 as a driving force. be able to. Similarly, the notch precision grinding stone lifting mechanism 36 can also be configured using a ball screw.

As shown in FIGS. 2 and 11, the carry-out arm 16 is hung from the ceiling side on the side wall 29 side in the vicinity of the processing table 2, and has an arm portion 16 a protruding in the horizontal direction. Is provided with an adsorption chuck 16b that adsorbs the wafer from above by a negative pressure, so that the wafer 1 can be held. A direct drive motor 16c is provided immediately above the suction chuck 16b, and the held wafer 1 can be rotated in the circumferential direction to be cleaned, dried and measured as described later.
The carry-out arm 16 includes a carry-out arm moving mechanism 38 for moving in the X-axis direction, a carry-out arm raising / lowering mechanism (not shown) for raising and lowering the arm portion 16a, and a carry-out arm turning mechanism (not shown) for turning the arm portion 16a. ) Is provided, and the processed wafer 1 can be transferred from each processing table 2 to the cassette arm 14.

As shown in FIG. 11, the carry-out arm 16 includes a cleaning mechanism 10 including three upper and lower water nozzles 10a, 10b, and 10c that discharges cleaning liquid, and three upper and lower air nozzles 11a, 11b, and 11c that discharge drying air. And a drying mechanism 11 comprising: When the wafer 1 is held by the arm portion 16a of the carry-out arm 16, the upper water nozzle 10a and the air nozzle 11a are installed so as to be inclined downward and above the wafer 1, and the upper surface of the wafer 1 is cleaned and dried. The water nozzle 10b and the air nozzle 11b in the middle stage are installed so as to be inclined upward and below the wafer 1, and the lower surface of the wafer 1 is cleaned and dried. The lower water nozzle 10c and the air nozzle 11c are installed so as to be inclined downward, and the stage 17 of the processing table 2 is washed and dried.
In this embodiment, the cleaning mechanism 10 and the drying mechanism 11 are arranged so that the stage 1 of the processing table 2 can be cleaned and dried while holding the wafer 1 above the processing table 2 and cleaning and drying the wafer 1. However, the wafer 1 may be cleaned and dried while the wafer 1 is placed on the processing table 2.

Further, the unloading arm 16 is provided with a post-process sensor 9 which is composed of a pair of upper and lower members and measures the radius of the wafer 1 and the shape of the notch 1n. After processing, the sensor 9 irradiates the laser from the upper member, and the laser received by the lower member is blocked by the wafer 1, thereby measuring the shapes of the peripheral end surface 1b and the notch 1n of the wafer 1, The radius of the wafer 1 is detected from the distance from the center.
Since the post-processing sensor 9 is pivotally attached to the carry-out arm 16, in order to measure the shape of the wafer 1, first, the post-process sensor 9 is placed directly above the wafer 1 with the carry-out arm 16 holding the wafer 1. Escape from. Next, the height of the arm portion 16a is raised to the height of the post-processing sensor 9, and the post-processing sensor 9 is swung and placed on the top and bottom of the wafer 1, whereby the shape of the wafer 1 can be measured. Further, the post-processing sensor 9 is provided above the cleaning mechanism 10 or the drying mechanism 11 so as not to become dirty when the wafer 1 is cleaned or dried. In addition, the post-processing sensor 9 may be configured to measure the shape of the wafer 1 while the wafer 1 is placed on the processing table 2.
If necessary, a camera may be mounted on the post-processing sensor 9 so that the chamfered widths X1, X2, and X3 of the edge 1a and the presence or absence of chipping (chips) can be measured.

Next, the chamfering process of the wafer 1 and the control of each part in this chamfering apparatus will be described.
In this chamfering device, the first process, the second process, the third process, and the fourth process are sequentially repeated for one processing table 2 to efficiently chamfer the wafer 1 with the four processing tables 2. Can do.

  In the first step, when there is a processed wafer 1 on the processing table 2, the unloading arm 16 adsorbs the processed wafer 1 and rotates it over the processing table 2, washing and drying the wafer 1 and the processing table 2, and processing. The rear sensor 9 measures the shape of the wafer 1 (see FIG. 11), delivers the wafer 1 from the carry-out arm 16 to the cassette arm 14, and stores it in the cassette 13 (see FIG. 2). Next, the unprocessed wafer 1 is taken out from the cassette 12 by the cassette arm 14, and the carry-in arm 15 receives this (see FIG. 2) and places it on the processing table 2 at the correct placement position based on the measurement of the alignment sensor 7. Then, the thickness of the wafer 1 is measured by the thickness sensor 8 (see FIG. 3).

In the second step, the grindstone moving mechanism 27 moves the grindstone support device 26 to the position of the machining table 2 in the X-axis direction, and the machining table approaching / separating mechanism 19 brings the machining table 2 close to the grindstone support device 26 so that the edge The edge 1a of the wafer 1 is chamfered with the rough grinding wheel 3, and then the notch 1n is chamfered with the notch rough grinding wheel 5 (see FIG. 5).
In chamfering, when the precise processing is performed while moving the position of the edge roughing grindstone 3 or the notch roughing grindstone 5 with respect to the wafer 1 in the X-axis direction, the rough grindstone moving mechanism 27 can accurately move the edge.

In the third step, the edge precision grinding wheel moving mechanism 33 moves the grinding wheel support device 30 to the position of the processing table 2 in the X-axis direction, the processing table approaching / separating mechanism 19 brings the processing table 2 close to the grinding wheel support device 30, The edge 1a of the wafer 1 is chamfered with the edge polishing grindstone 4 (see FIGS. 6 and 7).
In the chamfering process, when the precision machining is performed while moving the position of the edge fine grinding wheel 4 relative to the wafer 1 in the X-axis direction, the edge fine grinding stone moving mechanism 33 can precisely move the edge fine grinding stone 4.

In the fourth step, the notch precision grinding wheel moving mechanism 35 moves the grindstone support device 34 to the position of the processing table 2 in the X-axis direction, the processing table approaching / separating mechanism 19 brings the processing table 2 close to the grindstone support device 34, The notch 1n of the wafer 1 is chamfered with the notch fine grinding wheel 6 (see FIG. 10).
In chamfering, when the precision machining is performed while moving the position of the notch fine grinding wheel 6 relative to the wafer 1 in the X-axis direction, the notch fine grinding stone moving mechanism 35 can precisely move the wafer.
In this chamfering apparatus, the construction time of the first process, the second process, the third process, and the fourth process are all about 80 to 120 seconds, and variations in the construction time are reduced.

FIG. 12 is a timing chart for chamfering the wafer 1 with the chamfering apparatus. In FIG. 12, the vertical direction represents each processing table 2, and the horizontal direction represents elapsed time.
Hereinafter, the four processing tables 2 are distinguished as processing tables 2A, 2B, 2C, and 2D.
With this chamfering device, when chamfering is started from a state where the wafers 1 are not placed on all the processing tables 2, first, the second half of the first step, that is, the wafer 1 in the cassette 12 is taken out from the processing table 2A. To the process until the thickness is measured on the processing table 2A (t1).

When this is completed, the second step is then performed on the processing table 2A, and at the same time, the latter half of the first step is performed on the processing table 2B (t2).
When the operations of the processing tables 2A and 2B are completed, the third step is performed at the processing table 2A, the second step is performed at the processing table 2B, and the second step of the first step is performed at the processing table 2C. Is performed (t3).

When all the operations of the processing tables 2A to 2C are completed, the fourth step is performed at the processing table 2A, the third step is performed at the processing table 2B, and the second step is performed at the processing table 2C. The second half of the first step is performed on the processing table 2D (t4).
When the operation is completed in all the processing tables 2A to 2D, next, all the processes of the first process are performed in the processing table 2A, and all the processes associated with the chamfering process of the wafer 1 are finished, and the new wafer 1 is chamfered. Start processing. At the same time, the fourth step is performed on the processing table 2B, the third step is performed on the processing table 2C, and the second step is performed on the processing table 2D (t5).

Thereafter, the first process to the fourth process are sequentially repeated in each processing table 2, and in each processing table 2, different processes depending on the grindstone and the like are performed in parallel.
Each grindstone 3, 4, 5, 6, carry-in arm 15 and carry-out arm 16 approaches one processing table 2 to process or process the wafer 1, and then sequentially moves to another processing table 2 to process or process the wafer 1. Processing will be repeated. In the movement between the processing tables 2, the grindstone support device 26 and the grindstone support device 30, and the carry-in arm 15 and the carry-out arm 16 may pass each other. , So that they can pass each other without contact (FIG. 2).

  In such a chamfering apparatus, a plurality of grindstones 3, 4, 5, 6, sensors 7, 8, 9 and cleaning mechanisms respectively corresponding to a plurality of types of processing steps (first to fourth steps) in chamfering the wafer 1 are provided. 10 and the drying mechanism 11 are each provided with a moving mechanism for moving between the processing tables 2, so that different processing steps can be performed simultaneously on the plurality of processing tables 2, and the throughput of the chamfering device is increased. Can do. Further, since the number of grindstones, sensors, cleaning mechanisms, and drying mechanisms in the entire chamfering device can be suppressed, the cost of the chamfering device can be reduced and the management burden of the grindstone can be reduced.

  Further, by using a ball screw or the like for the rough grinding wheel moving mechanism 27, the edge fine grinding wheel moving mechanism 33, and the notch fine grinding wheel moving mechanism 35, each of the grinding stones 3, 4, 5, 6 is placed between the machining tables 2 (X axis). The grindstones 3, 4, 5, and 6 can be moved precisely in the X-axis direction during chamfering, thereby reducing the cost of the precision chamfering machine in the entire chamfering device. Can do.

  Further, the sensors 7, 8 and 9, the cleaning mechanism 10 and the drying mechanism 11 perform measurement, cleaning and drying at a position where the wafer 1 is held above each processing table 2 or placed on each processing table 2. As a result, all processes associated with the chamfering process of the wafer 1 can be performed in the vicinity of one processing table 2, and it is not necessary to provide an independent space for measurement, cleaning and drying, thus saving the chamfering device. In addition, the time of the first process associated with the chamfering process can be shortened and the throughput can be improved.

  In particular, the unloading arm 16 holds the wafer 1 above the processing table 2, cleans the wafer 1 simultaneously with the cleaning mechanism 10, and simultaneously cleans the processing table 2, and then dries the wafer 1 with the drying mechanism 11 and simultaneously processes the processing table 2. By drying, the time required for the first step can be further shortened, and the throughput of the chamfering apparatus can be improved.

  In addition, an alignment sensor 7 and a thickness sensor 8 are provided on the loading arm 15 for transporting the unprocessed wafer 1 from the cassette 12 to each processing table 2, and the processed wafer 1 is transported from each processing table 2 to the cassette 13. Since the post-processing sensor 9, the cleaning mechanism 10, and the drying mechanism 11 are provided on the carry-out arm 16, it is necessary to provide a separate machine for moving the sensors 7, 8, 9, the cleaning mechanism 10 and the drying mechanism 11 in the X-axis direction. Therefore, the cost of the entire chamfering device can be reduced and the space can be saved.

Further, since the four processing tables 2 are arranged in a straight line, the dead space is small (compared to a case where the processing tables 2 are arranged in an annular shape), and the chamfering device can be saved.
Further, by providing the machining table 2 with the machining table approaching / separating mechanism 19 and the machining table rotating mechanism 18, the machining table 2 is moved closer to and away from the grindstones 3, 4, 5, 6 as required. In addition to chamfering into a cross-sectional shape, the processing table 2 can be rotated to chamfer the entire circumference of the edge 1a of the wafer 1 and the notch 1n.

DESCRIPTION OF SYMBOLS 1 Wafer 1a Edge 1b Peripheral end surface 1n Notch 2 Processing table 3 (Edge roughing) Grinding wheel 4 (Edge fine study) Grinding wheel 4a (Disk) Grinding stone 5 (Notch rough grinding) Grinding stone 6 (Notch fine study) Grinding stone 7 (Alignment) sensor 8 (Thickness) sensor 9 (After processing) Sensor 10 Cleaning mechanism 10a to c Water nozzle 11 Drying mechanism 11a to c Air nozzle 12 Cassette 13 Cassette 14 Cassette arm 14a Arm unit 15 Loading arm 15a Arm unit 15b Adsorption chuck 15c Direct drive Motor 16 Unloading arm 16a Arm portion 16b Adsorption chuck 16c Direct drive motor 17 Stage 18 Processing table rotating mechanism 19 Processing table approaching / separating mechanism 20 Cassette arm X-axis moving mechanism 21 Cassette arm Y-axis moving mechanism 22 Cassette Arm lifting mechanism 23 cassette arm turning mechanism 24 carry-in arm moving mechanism 26 grinding wheel support device 27 rough grinding wheel moving mechanism 28 rough grinding wheel lifting mechanism 30 grinding wheel support device 31 supporting device lifting mechanism 32 edge precision grinding stone lifting mechanism 33 edge precision grinding stone Moving mechanism 34 Grinding wheel support device 35 Notch precision grinding wheel moving mechanism 36 Notch precision grinding wheel lifting mechanism 38 Unloading arm moving mechanism 40 Processing unit 41 Processing table 42 Grinding stone 43 Grinding wheel 45 Pre-setting unit 47 Cleaning unit X, Y Horizontal direction

Claims (10)

A plurality of processing tables each carrying one wafer;
A plurality of grindstones having different processing characteristics respectively corresponding to a plurality of types of processing steps for chamfering the peripheral edge of the wafer placed on each of the plurality of processing tables ;
A grindstone moving means for independently moving a plurality of grindstones having different processing characteristics corresponding to the plurality of types of processing steps, respectively, between the plurality of processing tables;
While one grindstone is processing a wafer placed on one processing table, another grindstone is processing another wafer placed on another processing table, and each grindstone is processed multiple times. A wafer chamfering apparatus, wherein the plurality of wafers chamfer the plurality of wafers simultaneously in parallel by sequentially moving the table and sequentially processing the wafers placed on each processing table .   2. The wafer according to claim 1, wherein the grindstone moving means precisely moves the position of the grindstone in the moving direction between the processing tables when chamfering the wafer placed on the processing table. Chamfering device. A plurality of processing tables each carrying one wafer;
A grindstone that chamfers the peripheral end surface of the wafer placed on each of the plurality of processing tables ,
Whetstone moving means for moving the whetstone between the plurality of processing tables;
Before chamfering of the wafer, and machining before sensors that detect the shape or the placing position of the wafer at a position held above the work table to be the placing of the wafer,
A pre-processing sensor moving means for moving the pre-processing sensor between the plurality of processing tables;
While the grindstone is processing a wafer placed on one processing table, the pre-processing sensor detects the shape or placement position of another wafer above another processing table in parallel. A wafer chamfering device. A plurality of processing tables each carrying one wafer;
A grindstone for chamfering the peripheral end surface of each wafer placed on each of the plurality of processing tables ;
One or more post-processing sensors for measuring different measurement objects to detect the shape of the wafer after chamfering the wafer;
A post-processing sensor moving means for moving the post-processing sensor between the processing tables;
The wafer chamfering apparatus, wherein the post-processing sensor measures the shape of the wafer at a position where the wafer is held above each processing table or placed on each processing table. A plurality of processing tables each carrying one wafer;
A grindstone for chamfering the peripheral end surface of each wafer placed on each of the plurality of processing tables ;
A wafer cleaning mechanism for cleaning the wafer after chamfering the wafer;
A wafer drying mechanism for drying the wafer after cleaning;
A post-processing mechanism moving means for moving the wafer cleaning mechanism and the wafer drying mechanism between the processing tables;
A wafer chamfering apparatus, wherein the wafer cleaning mechanism or the wafer drying mechanism cleans or dries the wafer at a position where the wafer is held above each processing table or a position where the wafer is placed on each processing table.   The wafer is held above the processing table and cleaned by the wafer cleaning mechanism and at the same time the processing table is cleaned, and then the wafer is dried by the wafer drying mechanism and at the same time the processing table is dried. The wafer chamfering apparatus according to claim 5.   The pre-processing sensor, the post-processing sensor, the wafer cleaning mechanism, or the wafer drying mechanism transports the wafer between the processing table and the cassette for storing the wafer before and after chamfering. The wafer chamfering apparatus according to claim 3, wherein the wafer is chamfered.   The wafer chamfering apparatus according to claim 1, wherein the plurality of processing tables are linearly arranged. A processing table for moving the processing table in a direction perpendicular to the moving direction of any one of the grinding wheel moving means, the pre-processing sensor moving means, the post-processing sensor moving means, or the post-processing mechanism moving means. Access and separation means;
6. The wafer chamfering apparatus according to claim 1, further comprising processing table rotating means for rotating the processing table. A plurality of processing tables each carrying one wafer;
A grindstone that chamfers the peripheral end surface of the wafer placed on each of the plurality of processing tables,
Whetstone moving means for moving the whetstone between the plurality of processing tables;
Before chamfering the wafer, a pre-processing sensor that detects the thickness of the wafer at a position where the wafer is placed on the processing table;
A pre-processing sensor moving means for moving the pre-processing sensor between the plurality of processing tables;
While the grindstone is processing a wafer placed on one processing table, the pre-processing sensor detects the thickness of another wafer on another processing table simultaneously in parallel. Chamfering device.

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