JP2016136559A - Workpiece cutting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a workpiece cutting method that enables perfect removal of sawdust.SOLUTION: In a workpiece cutting method for cutting, with a cutting blade, a plate-shaped workpiece having a surface on which devices are formed in respective regions compartmented by plural parting schedule lines formed in a grid form, a workpiece semiconductor wafer (11) is supported by an annular frame F through a dicing tape T, water-resoluble resin is applied on the surface of the workpiece to form a resin film 14, a cutting blade 30 cuts into the workpiece from the surface thereof along the parting schedule lines while rotated at high speed, the workpiece is divided into plural chips without supplying cutting water to the workpiece, and then water is supplied to the surface of the workpiece to remove the resin film from the workpiece, whereby sawdust 21 occurring and adhering to the resin film in the dividing step can be removed from the workpiece together with the resin film.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a method for cutting a plate-like workpiece such as a wafer.

  A semiconductor wafer in which a number of devices such as IC and LSI are formed on the surface, and each device is partitioned by a plurality of division lines, the back surface is ground by a grinding machine and processed to a predetermined thickness, and then cut. A line to be divided is cut by an apparatus and divided into individual device chips, and the divided device chips are widely used in various electronic devices such as mobile phones and personal computers.

  Cutting by a cutting apparatus is used not only for dividing wafers such as semiconductor wafers and optical device wafers into individual chips, but also for dividing plate-like workpieces such as glass and ceramics.

  Since the division of the workpiece by the cutting blade is a crushing process, cutting waste is always generated. Therefore, in cutting with a cutting blade, in order to prevent adhesion of cutting waste, cutting is performed while supplying a cutting fluid, and after the cutting, a cleaning process for removing cutting waste is performed (for example, JP 2000-306878 A). No. publication).

  However, it is very difficult to wash away all the fine cutting chips adhering to the surface of the workpiece, and improvement of a two-fluid nozzle that injects water and high-pressure air in the cleaning process has been performed (Japanese Patent Laid-Open No. 2004). No. -308555).

JP 2000-306878 A JP 2004-303855 A

  However, there are cases where the cutting waste firmly adhered to the surface of the workpiece cannot be completely removed even if it is cleaned in the cleaning step after the cutting process.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a cutting method for a workpiece capable of completely removing cutting chips adhering to the surface of the workpiece by cutting. It is to be.

  According to the present invention, there is provided a cutting method for a workpiece, in which a plate-like workpiece having a surface on which a device is formed in each region partitioned by a plurality of division lines formed in a lattice shape is cut with a cutting blade. A support step of supporting the workpiece with an annular frame via a dicing tape, and a coating step of forming a resin film by applying a water-soluble resin to the surface of the workpiece after performing the support step. After performing the coating step, the workpiece is cut into a plurality of chips without cutting water from the surface of the workpiece along the division line while rotating the cutting blade at high speed without supplying cutting water to the workpiece. Generated in the dividing step, and a removing step of supplying water to the surface of the workpiece and removing the resin film from the workpiece after the dividing step is performed. Cutting chips adhered to the resin film, cutting method of the workpiece, characterized in that it is removed from the workpiece by said removal step with the resin film is provided.

  Preferably, after the coating step is performed and before the dividing step is performed, a curing step is performed in which the resin film is cured by irradiation with ultraviolet rays. Preferably, the water supplied in the removing step is jetted as two fluids having a predetermined pressure or higher together with high-pressure air.

  According to the workpiece cutting method of the present invention, before the dividing step, the surface of the workpiece is coated with a water-soluble resin film, and the workpiece is divided with a cutting blade without supplying cutting water. Since the resin film stays on the surface of the work piece, the cutting waste generated by the cutting process adheres to the resin film, and the resin film is removed by the removing step. Can be completely removed from the surface.

It is a perspective view which shows the support step which supports a wafer with an annular frame via a dicing tape. It is a partial cross section side view which shows a covering step. It is a partial cross section side view which shows a hardening step. It is a partial cross section side view which shows a division | segmentation step. It is a partial cross section side view which shows a removal step. It is a partial cross section side view after implementation of a removal step.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, there is shown a perspective view of a supporting step for supporting a semiconductor wafer (hereinafter sometimes simply referred to as a wafer) 11 with an annular frame F via a dicing tape T.

  On the surface 11 a of the semiconductor wafer 11, devices 15 such as ICs and LSIs are formed in each region partitioned by a plurality of division lines 13 formed in a lattice pattern. In the supporting step, the back surface of the wafer 11 is attached to a dicing tape T whose outer peripheral portion is attached to the annular frame F, and the wafer unit 17 is formed.

  The workpiece to be processed by the cutting method of the present invention is not limited to the semiconductor wafer 11, but the surface on which the device is formed in each region partitioned by a plurality of division lines formed in a lattice shape. The cutting method of the present invention can also be applied to other plate-like workpieces such as optical device wafers having

  After the support step, a coating step is performed in which a water-soluble resin is applied to the surface 11a of the wafer 11 to form a resin film. This coating step is performed by, for example, a resin film coating apparatus. As an alternative, a coating apparatus for coating a resin film may be incorporated in the cutting apparatus.

  In the covering step, as shown in FIG. 2, the wafer 11 is sucked and held via the dicing tape T by the chuck table 2 of the resin film coating apparatus, and the annular frame F is clamped and fixed by the clamp 4.

  A resin supply nozzle 10 is disposed at the tip of the arm 8 of the coating unit 6. The arm 8 is rotated to position the resin supply nozzle 10 above the center portion of the wafer 11, and the resin supply is performed while rotating the chuck table 2. A water-soluble resin 12 is supplied from the nozzle 10 onto the surface 11 a of the wafer 11.

  Since the wafer 11 held on the chuck table 2 is rotating, the water-soluble resin 12 supplied to the surface 11a of the wafer 11 is spin-coated to a uniform thickness over the entire surface 11a. The water-soluble resin 12 is preferably a resin having a certain degree of viscosity. For example, BIOSURFINE AWP (registered trademark) provided by Toyo Gosei Kogyo Co., Ltd. can be used.

  After performing the coating step, preferably, a curing step is performed in which the resin film is cured by irradiating the resin film with ultraviolet rays. In this curing step, the resin film 14 is cured (gelled) by irradiating the resin film 14 coated on the surface 11a of the wafer 11 with ultraviolet rays from the ultraviolet irradiation unit 16, as shown in FIG.

  However, in the method for cutting a workpiece of the present invention, a curing step for curing the resin film 14 applied to the surface 11a of the wafer 11 is not essential, and the resin film 14 is applied without being cured by irradiation with ultraviolet rays. You may make it leave in a state and implement the division | segmentation step demonstrated later.

  After performing the coating step or after performing the coating step and the curing step, the wafer 11 is divided into a plurality of device chips by cutting the wafer 11 from the surface 11a of the wafer 11 along the division line 13 to the dicing tape with a cutting blade. Perform the steps.

  This division step will be described with reference to FIG. In the division step, the chuck table 20 is processed and fed by rotating the cutting blade 30 attached to the tip of the spindle 28 at high speed (for example, 30000 rpm) in the direction of arrow A without supplying cutting water to the wafer 11. Thus, the cutting groove 19 reaching the dicing tape T is formed by cutting the wafer 11 along the division line 13.

  While the chuck table 20 is indexed and fed by the pitch of the planned dividing line 13, the cutting groove 19 is formed by the cutting blade 30 along all the planned dividing lines 13 extending in the first direction without supplying cutting water. .

  Next, after the chuck table 20 is rotated by 90 °, the cutting blade 30 is cut without supplying cutting water along all the planned dividing lines 13 extending in the second direction orthogonal to the first direction. Thus, the same cutting groove 19 is formed, and the wafer 11 is divided into individual device chips 23 (see FIG. 6). When the dividing step is performed, the cutting waste 21 adheres to the resin film 14 as shown in FIG.

  In the wafer cutting method of this embodiment, after performing the dividing step, water is supplied to the surface of the wafer 11 and a removing step of removing the water-soluble resin film 14 from the wafer 11 is performed.

  This removal step will be described with reference to FIG. A cleaning water jet nozzle 42 is attached to the tip of the arm 40 of the cleaning unit 38. The arm 40 is disposed so as to be rotatable between a retracted position where the cleaning water spray nozzle 42 is retracted from the chuck table 20 and a cleaning position positioned at a substantially central portion of the chuck table 20.

  The cleaning water injection nozzle 42 is selectively connected to a cleaning water supply source 46 via an electromagnetic switching valve 44 and is selectively connected to a compressed air supply source 50 via an electromagnetic switching valve 48.

  In the removal step of removing the resin film 14 coated on the wafer 11, the arm 40 is rotated to position the cleaning water spray nozzle 42 at the cleaning position, and both the electromagnetic switching valves 44 and 48 are switched to the communication position, thereby cleaning water. The resin film 14 is cleaned by jetting two fluids 52 composed of water and high-pressure air from the jet nozzle 42.

  Since the resin film 14 is formed of a water-soluble resin, the resin film 14 is melted by the two fluids 52 composed of water and air, and the resin film 14 can be removed from the surface 11 a of the wafer 11.

  Preferably, the removing step is performed while rotating the arm 40 between the cleaning position and the retracted position and rotating the chuck table 20 at a low speed. Thereby, since the two fluids 52 composed of water and high-pressure air are supplied to the entire surface of the resin film 14, the resin film 14 can be effectively removed from the surface 11 a of the wafer 11. Since the cutting waste 21 generated in the dividing step adheres to the resin film 14, the cutting waste 21 is removed from the wafer 11 together with the resin film 14.

  In the removal step of the present embodiment, the two fluids 52 composed of water and high-pressure air are injected from the washing water injection nozzle 42. However, since the resin film 14 is water-soluble, water is injected from the water injection nozzle 42. The resin film 14 may be removed.

  A partial cross-sectional side view after the removal step is performed is shown in FIG. The wafer 11 is divided into individual device chips 23 by cutting grooves 19 reaching the dicing tape T.

6 Coating unit 10 Resin supply nozzle 11 Semiconductor wafer 12 Water-soluble resin 14 Resin film 15 Device 17 Device unit 18 Cutting device 19 Cutting groove 20 Chuck table 21 Cutting waste 23 Device chip 30 Cutting blade

Claims (3)

A workpiece cutting method for cutting a plate-like workpiece having a surface on which a device is formed in each region partitioned by a plurality of division lines formed in a lattice shape with a cutting blade,
A support step for supporting the workpiece with an annular frame via a dicing tape;
A coating step for forming a resin film by applying a water-soluble resin to the surface of the workpiece after performing the supporting step;
After performing the coating step, the workpiece is cut into a plurality of chips without cutting water from the surface of the workpiece along the division line while rotating the cutting blade at a high speed. A splitting step to split;
A step of supplying water to the surface of the workpiece after removing the dividing step and removing the resin film from the workpiece;
Cutting material generated in the dividing step and attached to the resin film is removed from the workpiece together with the resin film in the removing step.   2. The method according to claim 1, further comprising a curing step of irradiating the resin film with ultraviolet rays and curing the resin film after performing the coating step and before performing the dividing step. How to cut the workpiece.   3. The method for cutting a workpiece according to claim 1, wherein the water jetted in the removing step is jetted as two fluids having a predetermined pressure or more together with high-pressure air.

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