JPH0212729B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wafer manufacturing method and apparatus for cutting columnar material into flaky wafers in the manufacturing process of semiconductors and the like.

Traditionally, materials such as silicon (called ingots)
In order to cut into wafers, the ingot was mainly pressed against a high-speed rotating internal blade, but there were problems such as the method of holding the cutting blade, imbalance in cutting performance between the two blade surfaces, unevenness in coolant, wind pressure, etc. Due to these reasons, it has been difficult to improve the flatness of the cut surface and, therefore, the surface precision of the cut wafer. Especially in recent years, there has been a strong technical demand for increasing the diameter of ingots in order to improve production efficiency, so-called large-diameter ingots. As a result, warpage (flatness error) on both sides of the wafer becomes large, which has become a problem. Further, if the wafer has a large warpage and the surface precision is poor, a large amount of man-hours and expense are required for post-process grinding, correction in the wrapping process, and finishing, and a satisfactory surface precision cannot always be obtained.

The present invention provides a method and apparatus for dramatically improving the flatness of at least one side of a wafer.

The present invention adds a function of surface grinding the end face of the ingot to the cutting function of a slicing machine that cuts wafers from the ingot. In other words, the cutting process and the end face grinding process of the ingot are performed in one machine, and the cut wafer is The flatness of one side of the ingot can be finished with high precision, and the end face grinding of the ingot may proceed simultaneously with cutting, or the end face grinding and cutting may be performed alternately.

Embodiments of the method and apparatus of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment in which the present invention is applied to a horizontal slicing machine in which an inner peripheral blade is attached to a hollow spindle. In the figure, an ingot 1 is attached to a hollow spindle 3, and is moved in the direction of arrow A by a holding mechanism and a feeding mechanism (not shown) against a blade 2 of an internal cutting edge that rotates at high speed, and is cut into thin wafers. . In the figure, in a horizontal slicing machine, a blade 2 of an inner circumferential cutter is stretched around a hollow spindle 3 that rotates at a high speed, and is rotated at a high speed. The ingot 1 is moved in the direction of arrow A by a holding mechanism and a feeding mechanism (not shown) and cut into thin wafers. On the other hand, a grindstone shaft 5A is disposed within a hollow spindle 3 on the same horizontal slicing machine, and a grindstone 5 is provided at the tip of the grindstone shaft 5A. When cutting a wafer, a rotating grindstone 5 for surface grinding is applied to the end surface 4 of the ingot 1, and when the ingot 1 is moved in the direction of arrow A, the end surface 4 is first ground by the grindstone 5, and then the blade 2 cuts into ingot 1 and cuts it into wafers.

At this time, the blade 2 and the grindstone 5 are arranged so that the tip of the cut of the blade 2 does not reach the part being ground by the grindstone 5 so as not to chip, crack, or crack the wafer to be cut. That is, grindstone 5
The grinding position of the end face of the columnar body is made to precede the cutting position of the columnar body by blade 2, and
The cutting position of the columnar body is always delayed from the position of grinding the end face of the columnar body. When the end face grinding is completed, the grinding wheel 5 moves backward (moves to the right in the figure), and the ingot 1 also returns to its original position to begin the next processing cycle. In this method, the end face grinding and cutting of the ingot 1 can be performed in parallel and almost simultaneously, so there is no loss of time and it is extremely efficient.

The above embodiment is an example in which a hollow spindle 3 is used which can provide the blade 2 with an ingot end face grinding function and an ingot holding mechanism on the left and right sides. However, as shown in FIG. 2, in a method in which the blade 6 is attached to a rotating bowl-shaped holder 7, that is, a non-hollow spindle method, a grindstone and a grindstone shaft cannot be provided inside the bowl-shaped holder 7. Can not. Therefore, at this time, on the same machine for horizontal slicing, an end face grinding wheel 8 is provided close to the side of the bowl-shaped holder 7 of the blade 6, facing toward the end face of the ingot 1, and the ingot 1 moving mechanism is Immediately before the cutting process, the ingot 1 is moved to the position of the grindstone 8 as shown by the dashed line in FIG. , B, feed it into the central opening of the blade 6, and move it as shown by the arrow A.
The blade 6 cuts into the wafer by feeding the wafer in the same direction. Although this method requires a little extra time for processing, it can achieve almost the same results as the first embodiment.

Although the two embodiments have been described above, the method and apparatus of the present invention are not limited to these embodiments, but can also be applied to vertical type or peripheral blade type slicing machines.

As detailed above, by adopting the present invention, all the mechanisms of the slicing machine are used on the same machine, except for adding the end face grinding mechanism, and there is no need for setup changes such as ingot and mounting. , in parallel with the cutting process or during the cutting process cycle.
It becomes possible to grind the end face of the ingot with high precision. Therefore, it is no longer necessary to measure and manage the flatness of the ingot end face, and the quality of the cut wafers can be improved.
That is, the flatness of one side can be dramatically improved. In addition, the number of man-hours and costs of post-processing can be significantly reduced, productivity can be increased, and other great effects can be obtained.

[Brief explanation of drawings]

FIG. 1 is a mechanism explanatory diagram of an embodiment of the present invention, and FIG. 2 is a mechanism explanatory diagram showing another embodiment. 1...Ingot, 2, 6...Blade, 4...
...End face, 5, 8... End face grinding wheel.

Claims (1)

[Scope of Claims] 1. In a wafer manufacturing apparatus in which a cutting blade is attached to a rotating spindle to cut a columnar material into thin pieces, a rotating grindstone shaft is attached near the cutting blade and the cut columnar material is cut into thin pieces. A wafer manufacturing apparatus characterized in that a grindstone for grinding an end face of a material is attached to the tip of the grindstone shaft. 2. The spindle is a hollow spindle formed hollow, the cutting blade is supported by the hollow spindle, and the grindstone is located within the hollow spindle and at a position facing an end surface of the columnar material. Claim 1 characterized by
wafer manufacturing equipment. 3. The grindstone is disposed close to the outside of the spindle, and the steps include cutting the columnar material into thin pieces with the cutting blade, and moving the cut columnar material to the position of the grindstone to cut the end surface. Claim 1, characterized in that it consists of a step of grinding.
wafer manufacturing equipment. 4. In a wafer manufacturing apparatus in which a cutting blade is attached to a rotating spindle to cut a columnar material into thin pieces, the cutting blade is cut by rotating a grindstone shaft having a grindstone at the tip attached near the cutting blade. A wafer manufacturing method characterized by grinding an end face of a columnar material. 5. The step of grinding and the step of cutting in a state where the grinding position of the end face of the columnar material by the grindstone located in the spindle formed in the hollow is in advance of the cutting position of the cutting blade of the columnar material. The wafer manufacturing method according to claim 4, characterized in that the above steps are carried out at the same time. 6 Cutting the columnar material into thin pieces with the cutting blade;
5. The wafer manufacturing method according to claim 4, wherein the cut columnar material is moved to a position of the grindstone disposed close to the outside of the spindle to grind the end surface.