KR20110135274A - Dicing device and dicing method of semiconductor wafer - Google Patents

Abstract

PURPOSE: A semiconductor wafer cutting apparatus and a cutting method thereof are provided to maintain fixed cutting force of a cutting blade, thereby manufacturing a semiconductor chip with uniform quality. CONSTITUTION: A wafer is placed on the upper surface of a wafer table. A cutting blade(140) cuts the wafer. A dressing board(150) is arranged in the outside of the wafer table. The dressing board comprises a grinder which is arranged on the upper surface of the dressing board in order to grind the cutting blade. The dressing board grinds the cutting blade in a position where extending a cutting path of the wafer. The dressing board is placed on a dressing board table(160).

Description

Cutting device and method for cutting semiconductor wafers {Dicing device and dicing method of semiconductor wafer}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer cutting device in a semiconductor device manufacturing apparatus, and more particularly to a cutting device for a semiconductor wafer in which a dressing board of a cutting blade is disposed outside the wafer table.

A plurality of semiconductor chips are made on the semiconductor wafer. A plurality of semiconductor chips made on a semiconductor wafer are individualized into individual semiconductor chips through a cutting process, that is, a dicing process. A cutting process is a sawing process of cutting a semiconductor wafer into individual semiconductor chips using a cutting blade that rotates at a high speed, and dressing is performed when the cutting blade deteriorates.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a semiconductor wafer cutting device capable of maintaining a constant wafer cutting function by efficiently performing dressing of a cutting blade to maintain a constant cutting force.

Another technical problem to be achieved by the present invention is to provide a method of cutting a semiconductor wafer using the cutting device to perform a cutting blade dressing process during a wafer cutting process.

A cutting device for semiconductor wafers of one embodiment of the present invention is provided. The cutting device of the semiconductor wafer includes a wafer table on which a wafer is located; A cutting blade capable of cutting the wafer; And a dressing board disposed on an outer side of the wafer table, the dressing board including a grinder on the upper surface of the wafer table, the dressing board extending the cutting path of the wafer. And configured to polish.

In some embodiments of the present invention, the dressing board may be arranged in a hollow shape around a region on which the wafer is placed on the wafer table.

In some embodiments of the present disclosure, the cutting device of the semiconductor wafer may further include a dressing board table on which the dressing board is placed.

A method of cutting a semiconductor wafer according to the present invention is provided. The method of cutting a semiconductor wafer comprises the steps of loading a wafer onto a wafer table; Cutting the wafer in one direction using a cutting blade; And dressing the cutting blade in an extended direction in a direction in which the wafer is cut, on a dressing board disposed outside the wafer table.

In some embodiments of the present disclosure, the dressing of the cutting blade may be performed after performing the cutting of the wafer a plurality of times.

In some embodiments of the present disclosure, the dressing of the cutting blade may be performed by fixing the cutting blade and moving the wafer table and the dressing board in a direction opposite to the direction in which the wafer is cut. .

According to the cutting device and the cutting method of the semiconductor wafer of the present invention, by maintaining a constant cutting force of the cutting blade it is possible to produce a semiconductor chip of a uniform quality, the dressing operation can be made during the cutting operation can improve the work efficiency. .

1 is a perspective view illustrating an apparatus for cutting a semiconductor wafer according to an embodiment of the present invention.
FIG. 2 is a partial cross-sectional view of the cutting blade taken along the cutting line II ′ of FIG. 1 to illustrate the autogenous action of the cutting blade. FIG.
3A to 3D are front views showing a portion of a cutting blade in which autogenous action is not normally performed and enlarged photographs thereof.
4 is a perspective view illustrating an apparatus for cutting a semiconductor wafer according to another embodiment of the present invention.
5 is an enlarged photograph of a portion of a cutting blade in which autogenous action is normally performed.
6 is a flowchart showing a process sequence of a semiconductor wafer cutting method according to the present invention.

The embodiments of the present invention illustrated in the following may be modified in many different forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. Embodiments of the invention are preferably interpreted to be provided to more completely explain the present invention to those skilled in the art. Like numbers refer to like elements all the time. Further, various elements and regions in the drawings are schematically drawn. Accordingly, the present invention is not limited by the relative size or spacing drawn in the accompanying drawings.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the expression “comprises” or “having” is intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and that one or more other features It should be understood that it does not exclude in advance the possibility of the presence or addition of numbers, operations, components, parts or combinations thereof.

In general, a semiconductor manufacturing process includes a process of forming a circuit pattern on a surface of a wafer by performing diffusion, photography, etching, and thin film processes on a wafer, a process of inspecting electrical characteristics of the circuit patterns, and a sawing process of individualizing chips. .

1 is a perspective view illustrating a cutting device of a semiconductor wafer according to an embodiment of the inventive concept, and FIG. 2 is taken along the cutting line I-I 'of FIG. 1 to illustrate autogenous action of the cutting blade. Partial cross-sectional views of a cutting blade.

Referring to FIG. 1, a cutting device of a semiconductor wafer includes a wafer table 110, a cutting blade 140, and a dressing board 150 disposed on one side of the wafer table 110. The wafer 130 is seated on the upper surface of the wafer table 110. The wafer 130 defines a plurality of semiconductor chips 132 on the active surface and includes scribe lines 134 that provide cutting lines. The semiconductor chips 132 may include integrated circuits such as DRAM devices, SRAM devices, phase change memory (PRAM) devices, and memory devices such as flash memory devices, or non-memory devices such as logic devices. have. More specifically, the semiconductor chips 132 may include transistors, resistors, and wirings, and may include conductive pads exposed to the outside to be electrically connected to the outside. The tape 120 may be attached to the inactive surface of the wafer 130 so that each semiconductor chip 132 is not scattered when the individual semiconductor chips 132 are cut and separated from the wafer 130. The cutting blade 140 is typically rotated at 10,000 rpm to 50,000 rpm to cut the wafer 130 along the scribe line 134 of the wafer 130. The cutting blade 140 may be fixed and the wafer table 110 may be moved, or the wafer table 110 may be fixed and the cutting blade 140 may be moved. The cutting blade 140 may be configured in various shapes to reduce the resistance during cutting and to suppress the chipping of the wafer 130. The cutting blade 140 may be a hub type or a hubless type, and a diamond blade may be used in view of high durability.

Referring to FIG. 2 together with FIG. 1, the cutting blade 140 may have a structure in which the cutting fine particles 144 are disposed on the base material 142. In this case, the base material 142 may be nickel (Ni), iron (Fe), cobalt (Co) or copper (Cu), and the cut fine particles 144 may be diamond. The size of the cut fine particles 144 may vary depending on the type of the wafer 130 to be cut, and in the case of the silicon (Si) wafer 130, 4-6 μm, and in the case of the gallium arsenide (GaAs) wafer 130. May be 2-4 μm. When the cutting blade 140 is worn or the edge is degraded (degradation), the cutting ability is reduced, the shape of the cut wafer 130 is uneven and chipping on the cutting blade 140 itself or the wafer 130 Chipping or cracking may occur. For long-term stable cutting results, it is necessary to maintain a constant processing load that the cutting blade 140 exerts on the wafer 130 at the time of cutting and to promote autogenous action of the cutting blade 140. The autogenous action of the cutting blade 140 refers to an action of newly exposing the cut fine particles 144 exposed to prevent the degradation of the cutting quality of the wafer 130 and maintain a constant cutting force. According to the autogenous action of the cutting blade 140, even if the cutting fine particles 144 excreted in the base material 142, as shown in Figure 2 after the new cutting fine particles 144 are exposed to maintain a constant cutting force .

The dressing board 150 rotates the cutting blade 140 on the dressing board 150 so that the base material 142 is polished, thereby effectively exposing the cutting fine particles 144 to activate the autogenous action. Accordingly, the dressing board 150 includes an abrasive material, which is a grinder for polishing the cutting blade 140, and may be in the form of a grind stone or abrasive cloth. According to the present invention, the dressing board 150 may be arranged to polish the cutting blade 140 at a position extending the cutting path of the wafer 130. Thus, after the cutting blade 140 performs a row of cutting operations along the scribe line 134 on the wafer 130, the cutting blade 140 continues past the dressing board 150 on the side of the wafer table 110 along the cutting direction. While dressing can be. Instead of dressing the cutting blade 140 only after the cutting operation is performed on all of the one wafer 130 or when the cutting blade 140 is replaced, the cutting process for one row of the wafer 130 and subsequent rows may be performed. Since the cutting blade 140 may be dressed between the cutting processes, the sharpness of the cutting blade 140 may be easily maintained. Recently, the size of the wafer 130 has tended to increase from 200 mm to 300 mm, and according to the cutting device of the present invention, dressing of the cutting blade 140 may be performed during cutting of the wafer 130. Regardless of the size of the wafer 130, the same level of cutting quality can be expected.

The dressing board 150 may be partially extended and attached to the side of the wafer table 110, or the dressing board 150 may be in contact with or attached to the side of the wafer table 110. The portion where the wafer 130 is placed and the portion where the dressing board 150 is placed may be in contact with each other. The upper surface of the wafer 130 and the upper surface of the dressing board 150 may be at the same height, whereby after the cutting operation by the cutting blade 140, the cutting blade 140 is stepped in the cutting progress direction without step. The dressing operation can be made by moving continuously. In this case, the cutting blade 140 may be fixed and the wafer table 110 may be moved. The dressing board 150 may have a curved surface having a curvature radius equal to the curvature radius of the wafer 130, and may be in contact with the wafer 130 or the wafer table 110. The shape and size of the dressing board 150 may vary, and are not limited to the shapes shown in the drawings.

The dressing board 150 may be attached onto a separate dressing board table 160 as shown in FIG. 1, and the dressing board table 160 may be disposed to be in contact with the side surface of the wafer table 110. The wafer table 110 and the dressing board table 160 may be chuck tables that suction-fix the wafer 130 by vacuum. The chuck of the chuck table may be a porous chuck with several air inlets. When the wafer table 110 and the dressing board table 160 are chuck tables, the wafer table 110 and the dressing board table 160 use separate chucks, and thus, on one chuck table, the wafer 130 And the situation can be avoided by using the dressing board 150 to replace the work time can be saved. In addition, the chuck of the wafer table 110 and the chuck of the dressing board table 160 may be controlled separately.

3A to 3D are front views showing a part of the cutting blade 140 in which autogenous action is not normally performed and enlarged photographs thereof. In the following, reference is made to the components of the semiconductor cutting device of FIG. 1.

3A and 3B, the cutting fine particles 144 at the ends of the cutting blades 140 are worn, and the cutting fine particles 144 are not exposed by autogenous action. Recently, with the introduction of SIP (System In Package), IC card and RFID tag for mobile products, products using the wafer 130 having a thickness of 100 μm or less have been put to practical use in the semiconductor field. The importance of the technique of cutting the wafer 130 is increasing. As wafer 130, which is the workpiece, becomes thinner, backside chipping tends to increase, and in the case of thin wafer 130, it is difficult to expect an increase in processing load. Increasing importance

3C and 3D, the cutting blade 140 shows a state where foreign matter is caught. The low-k wafer 130 can be easily broken, so that metal wires, particles, etc. on the wafer 130 can be easily caught in the cutting blade 140. In this case, if the autogenous action is not performed normally, the cutting ability of the wafer 130 may be reduced, and the cutting quality may be degraded due to chipping or cracking, which may cause a defect of the wafer 130. Therefore, the importance of the process of dressing the cutting blade 140 so that the autogenous action takes place is emphasized.

4 is a perspective view illustrating an apparatus for cutting a semiconductor wafer according to another exemplary embodiment of the inventive concept.

Referring to FIG. 4, a dressing board 150 is disposed around the area where the wafer 130 on the wafer table 110 is placed. The top surface of the wafer 130 and the top surface of the dressing board 150 may be the same height, and the dressing board 150 dresses the cutting blade 140 at a position extending the cutting path of the wafer 130. can do.

According to the wafer cutting device of the present invention, the cutting of the wafer 130 and the dressing of the cutting blade 140 may proceed simultaneously without a separate working table for the dressing process. Therefore, a process such as replacing the wafer 130 and the dressing board 150 is not required to perform the dressing of the cutting blade 140 while cutting the single wafer 130. In addition, since the cutting blade 140 may be dressing between cutting operations of each row, even if the cutting force of the cutting blade 140 is reduced while cutting one wafer 130, the risk of failing to dress the blade may be avoided. .

5 is an enlarged photograph of a portion of the cutting blade 140 in which autogenous action is normally performed.

Referring to FIG. 5, when the dressing of the cutting blade 140 is performed during a cutting operation using the cutting device of the semiconductor wafer according to the present invention, since the autogenous action of the cutting blade 140 occurs constantly, the cutting fine particles 144 may be constantly exposed.

6 is a flowchart illustrating a cutting process of the wafer 130 using the cutting device of the semiconductor wafer according to the technical idea of the present invention in a process order.

Cutting of the semiconductor wafer 130 may begin with the step S1 of loading the wafer 130, which is the workpiece, into the wafer table 110. Wafer 130 may be transferred from wafer cassette to wafer table 110 by a transfer means such as, for example, a robot arm or a transfer arm. The wafer table 110 may be a chuck table for fixing the wafer 130 by a vacuum, and a cutting blade 140 for cutting the wafer 130 is positioned on the top of the wafer table 110.

When the wafer 130 is loaded, a step S2 of aligning the position of the wafer 130 for accurate cutting of the wafer 130 is performed. This is to perform a cutting operation at regular intervals along the scribe line 134.

Next, the cutting step S3 of the wafer 130 is executed. Cutting step 140 for one or more rows of wafer 130 along the scribe line 134 by moving the cutting blade 140 rotating at high speed in the cutting direction or by moving the wafer table 110 in the opposite direction of the cutting process ( S3) is performed.

After the cutting step S3 of the wafer 130, the cutting blade 140 continues to move in the cutting progress direction and passes over the dressing board 150 to perform the dressing step S4 of the cutting blade 140. After the dressing step S4 of the present cutting blade 140, the cutting step S3 for the next row of the wafer 130 is performed again. Therefore, the cutting step S3 of the wafer 130 and the dressing step S4 of the cutting blade 140 may be alternately repeated a plurality of times. The dressing step S4 of the cutting blade 140 may be performed before or after cutting a row of wafers 130, or may be performed before or after cutting for two or more rows. The number and the frequency of the dressing may be changed according to the material, thickness and size of the wafer 130. A separate optical microscope is provided to check the wear of the cutting blade 140 or the shape of the cutting surface of the wafer 130, and to move the dressing board table so that the dressing of the cutting blade 140 is performed if necessary. Can be configured and software can be used. When implemented through software, the wafer 130 or the cutting blade 140 is inspected after performing a wafer 130 cutting operation on a specific number of rows. Before performing the operation, the dressing board 150 may be moved or the cutting blade 140 may be moved to perform the dressing on the cutting blade 140.

After the cutting operation for one wafer 130 is finished, step S5 is performed in which the wafer 130 is unloaded from the wafer table 110.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be clear to those who have knowledge of.

110: wafer table
120: tape
130: wafer
132: semiconductor chip
134: scribe line
140: cutting blade
142: base material
144: cut particulate
150: dressing board
160: dressing board table

Claims (6)

A wafer table on which a wafer is located on an upper surface;
A cutting blade capable of cutting the wafer; And
A dressing board disposed outside the wafer table, the dressing board including a grinder on the upper surface thereof, the grinder capable of grinding the cutting blade;
And wherein the dressing board is configured to polish the cutting blade at a position extending the cutting path of the wafer. The method of claim 1,
And the dressing board is arranged in a hollow shape around a region on which the wafer is placed on the wafer table. The method of claim 1,
And a dressing board table on which the dressing board is placed. Loading the wafer onto a wafer table;
Cutting the wafer in one direction using a cutting blade; And
Dressing the cutting blade in an extended direction in a direction in which the wafer is cut, on a dressing board disposed outside the wafer table;
Cutting method of a semiconductor wafer comprising a. The method of claim 4, wherein
The step of dressing the cutting blade is performed after the step of cutting the wafer a plurality of times, characterized in that the method of cutting a semiconductor wafer. The method of claim 4, wherein
The step of dressing the cutting blade, the cutting blade is fixed, the cutting method of the semiconductor wafer, characterized in that performed by moving the wafer table and the dressing board in a direction opposite to the direction in which the wafer is cut.

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