TW201509594A - Semiconductor wafer grinding apparatus, semiconductor wafer manufacturing method, and semiconductor wafer grinding method - Google Patents

Abstract

A semiconductor wafer grinding apparatus (1) includes a grinding wheel (10), a first drive means (20) configured to drive to rotate the grinding wheel, a wafer holder (30), and a second drive means (440) configured to drive to rotate the wafer holder. The grinding wheel includes a plurality of grindstones provided on a main surface (11b) of the grinding wheel that faces the wafer holder. The wafer holder supports a semiconductor wafer in a fashion that a to-be-ground surface of the semiconductor waver faces the main surface of the grinding wheel. Each of the grindstones extends radially from the center of the grinding wheel across the to-be-ground surface of the semiconductor wafer. The grinding wheel and the wafer holder are rotated to cause the grindstones to grind the to-be-ground surface of the semiconductor wafer.

Description

Semiconductor wafer grinding device, semiconductor wafer manufacturing method, and semiconductor wafer grinding method

The present invention relates to a semiconductor wafer grinding device, a method of manufacturing a semiconductor wafer, and a method of grinding a semiconductor wafer.

In the manufacturing process of the semiconductor element, the main plane of the semiconductor wafer is divided into a plurality of regions by a lattice-shaped dividing line, and elements such as ICs and LSIs are formed in these regions. Next, the semiconductor wafer is cut along the dividing line, and the semiconductor wafer is divided into individual semiconductor wafers (components). Before the semiconductor wafer is divided along the dividing line, the surface on the opposite side of the principal plane is ground to a predetermined thickness by a grinding device (for example, see Patent Document 1).

Figure 7 is a side elevational view of a conventional semiconductor wafer grinding apparatus. As shown in FIG. 7, a conventional semiconductor wafer grinding apparatus includes a base 101 that rotates a semiconductor wafer W, and a grinding wheel 102 that faces the base 101. The grinding wheel 102 has a diameter slightly smaller than the semiconductor wafer W, and a plurality of vermiculite 103 are provided along the peripheral portion of the surface facing the base 101. The semiconductor wafer W is fixed to the base 101, and the base 101 is rotated about the axis, and the ground surface Wa of the semiconductor wafer W is pressed by the vermiculite 103 while rotating the grinding wheel 102 about the central axis. Grinding (grinding) is performed on the ground surface Wa. Next, after the processing strain is removed by the ground surface Wa, the ground surface Wa is polished and finally processed into a mirror shape.

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 10-156679

Conventional semiconductor wafer grinding devices have the problem of time consuming polishing steps. Reference Figure 8 illustrates this issue. Fig. 8 is a schematic view showing a ground surface Wa of a semiconductor wafer W which has been ground by a conventional semiconductor wafer grinding device.

In a conventional semiconductor wafer grinding device, the vermiculite 103 is ground to be ground Wa Since the center portion is centered and moved so as to draw a spiral track, there is a case where a fine spiral grinding groove Wb is formed on the ground surface Wa. In this case, in order to eliminate the grinding groove Wb in the polishing step, it is necessary to perform polishing by diamond abrasive grains before polishing by the slurry. Therefore, the polishing step takes longer than the case where the grinding groove Wb is not generated on the ground surface Wa, and the production efficiency of the semiconductor wafer W is lowered.

The present invention has been made in view of the above problems, and an object thereof is to provide a semiconductor The bulk wafer grinding device, the semiconductor wafer manufacturing method, and the semiconductor wafer grinding method can suppress the occurrence of the grinding grooves on the surface of the semiconductor wafer to be ground, and can improve the production efficiency of the semiconductor wafer.

A first aspect of the present invention is a study of a ground surface of a semiconductor wafer The sliced semiconductor wafer grinding device comprises: a grinding wheel; a first driving means for driving the grinding wheel to rotate about a central axis; and a wafer supporting tool supporting the semiconductor wafer and parallel to a central axis of the grinding wheel And rotating around an axis eccentric with respect to the central axis; a second driving means for driving the wafer support tool to rotate; wherein the grinding wheel has a plurality of meteorites, the plurality of meteorites being disposed opposite to the wafer supporting tool The wafer support tool supports the semiconductor wafer in such a manner that the ground surface of the semiconductor wafer is opposite to the main plane of the grinding wheel, and the plurality of meteorites respectively extend from the center of the grinding wheel to Radially shaped and formed across the ground surface of the semiconductor wafer.

According to the first aspect of the semiconductor wafer grinding device, because the vermiculite is in the semiconductor In the state in which the wafer is ground, the ground surface is moved in parallel with the ground surface to be ground, so that the occurrence of the grinding groove of the ground surface can be suppressed. Therefore, it is not necessary to perform polishing by diamond abrasive grains, and the production efficiency of the semiconductor wafer can be improved.

In one embodiment, the wafer support tool supports the plurality of semiconductor crystals A round way to form. In this case, since a plurality of semiconductor wafers can be ground at the same time, the production efficiency of the semiconductor wafer is improved.

In one embodiment, the semiconductor wafer grinding device has a plurality of the wafers Support tools. In this case, since a plurality of semiconductor wafers can be ground at the same time, the production efficiency of the semiconductor wafer is improved.

In addition, the second aspect of the present invention is a method of manufacturing a semiconductor wafer, including And a cutting process for cutting the ingot to obtain a semiconductor wafer; a grinding step of grinding the ground surface of the semiconductor wafer; and a polishing step of grinding the ground surface; wherein the grinding step is performed In a semiconductor wafer grinding apparatus of a first aspect, the ground surface is ground while the grinding wheel and the wafer supporting tool are rotated.

According to the second aspect of the method of manufacturing a semiconductor wafer, the polishing step can be suppressed The generation of the grinding groove of the ground surface of the semiconductor wafer. Therefore, it is not necessary to perform polishing by the diamond abrasive grains in the polishing step, so that the production efficiency of the semiconductor wafer is improved.

In addition, in the grinding step, it is preferable to make the grinding wheel and the wafer while The support tool is rotated in the same direction to grind the ground surface. Compared with the case where the grinding wheel and the wafer supporting tool are rotated in opposite directions, it is less likely to apply excessive force, so that the processed surface can be beautifully finished.

In addition, the third aspect of the present invention is a method for grinding a semiconductor wafer, In the semiconductor wafer grinding device of the first aspect, the ground surface is ground while the grinding wheel and the wafer supporting tool are rotated.

According to the grinding method of the semiconductor wafer of the third aspect, it is possible to suppress the occurrence of the grinding groove of the ground surface of the semiconductor wafer. Therefore, in the polishing step, it is not necessary to perform polishing by the diamond abrasive grains, so that the production efficiency of the semiconductor wafer is improved.

According to the present invention, it is possible to suppress the occurrence of the grinding grooves of the ground surface of the semiconductor wafer, and it is possible to improve the production efficiency of the semiconductor wafer.

1‧‧‧Semiconductor wafer grinding device

10‧‧‧ grinding wheel

10b‧‧‧main plane

13‧‧‧砥石

20‧‧‧1st drive mechanism (first drive means)

30‧‧‧ Wafer Support Tools

40‧‧‧2nd drive mechanism (2nd drive means)

W‧‧‧Semiconductor Wafer

Wa‧‧‧Spreaded noodles

1 is a flow chart showing a method of manufacturing a semiconductor wafer; FIG. 2 is a side view of a semiconductor wafer grinding apparatus according to an embodiment of the present invention; and FIG. 3 is a semiconductor wafer grinding apparatus shown in FIG. Stereogram 4 is a plan view of a grinding wheel of the semiconductor wafer grinding device shown in FIG. 2; and FIG. 5 is a bottom view of the wafer supporting tool of the semiconductor wafer grinding device shown in FIG. 2; FIG. FIG. 7 is a side view showing a conventional semiconductor wafer grinding device; and FIG. 8 is a conventional semiconductor wafer grinding device. Schematic diagram of the ground surface of the semiconductor wafer.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Before describing the present embodiment, a method of manufacturing a semiconductor wafer will be described with reference to FIG. 1 . Fig. 1 is a flow chart showing a method of manufacturing a semiconductor wafer.

As shown in Fig. 1, first, in step S10, a cylindrical ingot is cut to obtain a disk-shaped semiconductor wafer. Step S10 functions as a cutting step of the present invention. Next, in step S20, in order to avoid occurrence of cracks and defects in the peripheral portion of the semiconductor wafer, the peripheral portion of the semiconductor wafer is chamfered. Next, in step S30, the principal plane of the semiconductor wafer and the ground surface of the opposite side are ground (grinded) to bring the semiconductor wafer to a predetermined thickness. Step S30 functions as a polishing step of the present invention. Next, in step S40, the semiconductor wafer is etched to remove the processing strain generated by the grinding. Furthermore, in step S50, the ground surface of the semiconductor wafer is polished into a mirror shape. Step S50 functions as a polishing step of the present invention. Finally, in step S60, the semiconductor wafer is cleaned with medicinal water to remove impurities such as particles. In addition, at least one of steps S20, S40, and S60 may be omitted.

The semiconductor wafer grinding device of the present embodiment is used, for example, in the polishing step of step S30 of Fig. 1 . A semiconductor wafer grinding apparatus according to an embodiment of the present invention will be described with reference to Figs. 2 to 4 . 2 is a side view of a semiconductor wafer grinding device 1 according to an embodiment of the present invention, FIG. 3 is a perspective view of the semiconductor wafer grinding device 1, and FIG. 4 is a plan view of the grinding wheel 10 of the semiconductor wafer grinding device 1. 5 is a bottom view of the wafer support tool 30 of the semiconductor wafer grinding apparatus 1.

As shown in FIGS. 2 and 3, the semiconductor wafer grinding device 1 includes a grinding wheel 10, a first driving mechanism 20 as a first driving means, a pair of wafer supporting tools 30, and a second driving means. 2 drive mechanism 40.

The grinding wheel 10 includes a grinding wheel body 11 and a shaft 12. As shown in Figure 4, the grinding wheel The main body 11 is formed in a disk shape, and a through hole 11a into which the shaft 12 is fitted is formed at the center. A plurality of vermiculite 13 are disposed on the main plane 11b of the grinding wheel body 11 opposite to the wafer support tool 30. A plurality of vermiculite 13 are radially extended from the center of the grinding wheel body 11, and protrude from the main plane 11b in the direction of the central axis 14 of the shaft 12 (refer to Fig. 2).

The first drive mechanism 20 is composed of a motor or a speed reduction mechanism, and drives the grinding mill. The wheel 10 rotates about a central axis 14.

The wafer support tool 30 includes a holder 31 and a spindle 32. As shown in Figure 5, The holder 31 is formed in a disk shape and has a principal plane 31a which is opposed to the principal plane 11b of the grinding wheel 10. The mandrel 32 is vertically fixed to a central portion of the face on the opposite side of the main plane 31a of the holder 31. The axis 33 of the mandrel 32 (see FIG. 2) is parallel to the central axis 14 of the grinding wheel 10 and is eccentric with respect to the central axis 14.

On the main plane 31a of the holder 31, a plurality of semiconductor wafers W are detachably supported by fixing means. As a fixing means, for example, a wax or a binder can be used. The plurality of semiconductor wafers W are fixed to the principal plane 31a at a predetermined angular interval around the axis 33 of the mandrel 32, and the ground surface Wa faces the principal plane 11a of the grinding wheel 10. The wafer supporting tool 30 can be moved up and down in the direction of the axis 33 by a lifting mechanism (not shown), and can reach a processing position where the semiconductor wafer W abuts against the vermiculite 13 and a retracted position where the semiconductor wafer W is separated from the vermiculite 13 .

The second drive mechanism 40 is constituted by a motor, a speed reduction mechanism, or the like, and drives the wafer support tool 30 to rotate about the axis 33.

Next, a method of grinding the semiconductor wafer W by the semiconductor wafer grinding device 1 will be described with reference to FIG. Fig. 6 is an explanatory view showing a positional relationship between the grinding wheel 10 and the wafer support tool 30.

The pair of wafer support tools 30 (see FIG. 3) fix the plurality of semiconductor wafers W to the main plane 31a of the pair of wafer support tools 30 using a jig (not shown) in a retracted position (see Figure 5).

Second, the pair of wafer support tools 30 are lowered by the lifting mechanism and positioned at the processing position. Next, the grinding wheel 10 is driven to rotate by the first drive mechanism 20, and the second drive is driven. The mechanism 40 drives a pair of wafer support tools 30 to rotate in the same direction as the grinding wheel 10.

In addition, by driving the grinding wheel 10 and the wafer support tool 30 in the same direction When the grinding wheel 10 and the wafer supporting tool 30 rotate in opposite directions, the excessive force is less likely to be applied to the surface to be ground Wa, and the processing of the ground surface Wa can be performed beautifully.

The plurality of vermiculite 13 is slidably connected to the ground surface Wa of the plurality of semiconductor wafers W Touch, and grind the ground surface Wa. The plurality of vermiculite 13 are ground in parallel with the ground surface Wa, and the ground surface Wa is ground in a state of traversing the ground surface Wa of the semiconductor wafer W. Therefore, it is possible to suppress the occurrence of the grinding groove Wb as shown in Fig. 8 on the surface to be ground Wa, and the processing of the ground surface Wa can be performed beautifully. The reason will be described in detail below.

The conventional semiconductor wafer grinding device shown in Fig. 7 is transmitted by a so-called crack The material of the broadcast type is removed to grind the ground surface Wa. In this case, particularly in the case where the semiconductor wafer W is formed of a brittle material (such as germanium, glass, or the like), cracks easily remain on the ground surface Wa, and it is difficult to obtain a fine final processed surface, and the semiconductor wafer is The strength is also reduced.

On the other hand, the semiconductor wafer grinding device 1 of the present embodiment is connected by The grinding process of the ground surface Wa is performed by a near-plastic deformation type material removal processing method. In other words, since the plurality of radial vermiculite 13 slides on the ground surface Wa in a state of being traversed by the ground surface Wa, the temperature of the ground surface Wa is increased by the friction between the vermiculite 13 and the ground surface Wa. The stress at the lowering is lowered and the value of the fracture toughness is increased. As a result, since the crack propagation is suppressed, the cutting of the vermiculite 13 becomes shallow, and the damage distribution becomes shallow and uniform, so that the ground surface Wa can be beautifully processed.

Therefore, in the next polishing step, it is not necessary to eliminate the grinding groove Wb. Polishing with the diamond abrasive grains shortens the polishing step time as compared with the case where the grinding groove Wb is formed on the ground surface Wa. As a result, the production efficiency of the semiconductor wafer W is improved.

Although the specific embodiments of the present invention have been described above, the present invention is not limited to the embodiments shown in the first to sixth embodiments, and various modifications can be made to the present embodiment.

For example, in the present embodiment, the case where the semiconductor wafer grinding device includes a pair of wafer supporting tools has been described, but the number of wafer supporting tools may be one or three or more.

In addition, this embodiment has four semiconductor wafers on the wafer support tool. Although the case of being supported has been described, the number of semiconductor wafers supported by the wafer support tool may be three or less or five or more.

Further, in the present embodiment, the case where the wafer supporting tool and the grinding wheel are rotated in the same direction has been described. However, the wafer supporting tool and the grinding wheel may be rotated in different directions.

Further, various changes can be made to the embodiment without departing from the gist of the invention.

1‧‧‧Semiconductor wafer grinding device

10‧‧‧ grinding wheel

11‧‧‧ grinding wheel body

12‧‧‧Axis

13‧‧‧砥石

14‧‧‧ center axis

30‧‧‧ Wafer Support Tools

31‧‧‧Clamps

32‧‧‧ mandrel

33‧‧‧ axis

W‧‧‧Semiconductor Wafer

Claims (6)

A semiconductor wafer grinding device is a semiconductor wafer grinding device for grinding a ground surface of a semiconductor wafer, comprising: a grinding wheel; a first driving means for driving the grinding wheel to rotate around a central axis; a tool that supports the semiconductor wafer and is parallel to a central axis of the grinding wheel and rotatable about an axis that is eccentric with respect to the central axis; and a second driving means that drives the wafer to support tool rotation; wherein the grinding The grinding wheel is provided with a plurality of vermiculite, and the plurality of meteorites are disposed on a main plane opposite to the wafer supporting tool, wherein the wafer supporting tool has the ground surface of the semiconductor wafer opposite to the main plane of the grinding wheel The semiconductor wafer is supported, and the plurality of vermiculite are respectively extended from the center of the grinding wheel to a radial shape and formed to traverse the ground surface of the semiconductor wafer. The semiconductor wafer grinding device of claim 1, wherein the wafer support tool is formed in a manner to support a plurality of the semiconductor wafers. The semiconductor wafer grinding device of claim 1 or 2, wherein the semiconductor wafer grinding device comprises a plurality of the wafer support tools. A method of manufacturing a semiconductor wafer, comprising: a cutting step of cutting an ingot to obtain a semiconductor wafer; a grinding step of grinding the ground surface of the semiconductor wafer; and a polishing step of grinding the ground surface; In the polishing step, the semiconductor wafer grinding device according to any one of claims 1 to 3 is used, and the ground surface is ground while the grinding wheel and the wafer supporting tool are rotated. Grinding. The method of manufacturing a semiconductor wafer according to claim 4, wherein in the polishing step, the ground surface is ground while the grinding wheel and the wafer supporting tool are rotated in the same direction. A method for grinding a semiconductor wafer, which is a method for grinding a semiconductor wafer, and its characteristics In the semiconductor wafer grinding device according to any one of the first to third aspects of the invention, the ground grinding wheel is ground while the grinding wheel and the wafer supporting tool are rotated.