JP3460321B2 - Dicing and cutting method for semiconductor wafer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for dicing and cutting a semiconductor silicon wafer into a plurality of chips by dicing the silicon wafer with a dicing blade. About. 2. Description of the Related Art Pyrex glass or the like is used as a base of a semiconductor type dynamic quantity sensor (for example, a pressure sensor or an acceleration sensor). This is because the thermal expansion coefficient is relatively close to that of the semiconductor silicon wafer on which the sensor is formed, so that external thermal stress is cut off. For this reason, the thickness of the pedestal glass is about several mm. An anodic bonding method is used for bonding a semiconductor silicon wafer and a pedestal glass, and the shape of the pedestal glass is circular in accordance with the circular shape of the semiconductor silicon wafer. Then, the bonded semiconductor silicon wafer / pedestal glass structure is divided into a plurality of physical quantity sensor chips by dicing cut. FIG.
(A) is a schematic view of this conventional device at the time of dicing cut, and (b) is a view taken along the line BB '. In the figure, in a state where the semiconductor silicon wafer 1 is bonded on the circular pedestal glass 2, the rotating shaft 5 is moved in the direction indicated by reference numeral 7 while the dicing cut blade 4 is rotated in the rotation direction indicated by reference numeral 6. And make a dicing cut.
Numeral 3 indicates an invalid area (an area in which chipping at the time of cutting is anticipated and has no relation to electrical characteristics), and a dicing cut is performed in this invalid area. [0004] In such a conventional dicing cut, since the pedestal glass 2 is circular, if the cut of the dicing cut is a straight line perpendicular to the surface of the wafer / glass structure. However, there is a problem that it becomes oblique. That is, when the blade 4 enters the end face of the pedestal glass 2, since the pedestal glass 2 is circular, a reaction force to bend the blade 4 occurs as shown by reference numeral 8, thereby causing an oblique cut. I will. FIG. 2A shows the state of such an oblique cut.
2C, which is a cross section taken along line CC ′ of FIG. Reference numeral 20 denotes an obliquely cut portion. This obliquely cut portion occurs not only in the outer peripheral portion but also in the product chip portion. That is, if the diagonal cut is made at the beginning of the cutting, the diagonal cut is continued up to the center of the wafer of the product chip. When the diagonal cut is made in this way, an error occurs in handling of the cut chip or alignment of the bonded chip in assembling in a later step, which is a problem in terms of assembly characteristics. In order to prevent the oblique cut, it is effective to increase the blade thickness of the blade 4, but there is a problem that the ineffective area 3 occupying the semiconductor wafer 1 increases accordingly and the chip cost increases. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a dicing cut method in which an oblique cut does not occur even when a thin dicing cut blade is used. According to the present invention, in order to achieve the above object, a semiconductor silicon wafer (1) is bonded on a pedestal glass (12), and the bonded semiconductor silicon wafer / pedestal glass structure is provided. Is cut by a dicing cut blade (4) to obtain the semiconductor silicon.
In a method for dicing and cutting a semiconductor wafer wherein a wafer / pedestal glass structure is divided into a plurality of chips, a substantially square shape is used as the pedestal glass (12), and the blade (4) is The dicing cut is performed by vertically contacting the end surface of the base glass (12). [0008] The reference numerals in parentheses of the above means indicate the correspondence with the concrete means described in the embodiments described later. According to the present invention, since the shape of the pedestal glass is made substantially rectangular and the blade is perpendicularly applied to the end face of the pedestal glass to perform the dicing cut, the diagonal cut is performed. The dicing cut can be performed using a thin blade without worrying about the occurrence of the generation, and the width of the invalid area required for dicing can be reduced. The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 1 shows an embodiment of the present invention.
Is a schematic diagram at the time of dicing cut according to the present embodiment,
(B) is an AA 'arrow view. In the figure, the same components as those in FIG. 2 are denoted by the same reference numerals. As shown in FIG. 1, in this embodiment, a pedestal glass 1 to which a semiconductor silicon wafer 1 is bonded is provided.
The shape of No. 2 is square. Therefore, the blade 4 can be vertically applied to the end face of the pedestal glass 12, and the reaction force 8 as shown in FIG. 2 does not occur. Cut can be made. In such a dicing cut, the cutting of the semiconductor silicon wafer and the pedestal glass may be performed separately by using two blades. However, such a method increases the number of steps. On the other hand, in the present embodiment, the cutting is performed by one blade, so that the number of steps can be reduced, and the cutting can be performed with a thin blade to prevent oblique cutting. In the above embodiment, the shape of the pedestal glass 12 is square, but the present invention can be applied to a case where the four corners are obliquely cut to form an octagon. it can. Therefore, the pedestal according to the present invention, the blade only has to hit the end surface of the pedestal perpendicularly,
What is necessary is just a thing of a substantially square shape.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B show an embodiment of the present invention, in which FIG. 1A is a schematic diagram at the time of dicing cut, and FIG. FIG. 2 shows a conventional dicing cut method.
(A) is a schematic diagram at the time of dicing cut, (b) is B-
FIG. 6B is a sectional view taken along the arrow B ′, and FIG. [Description of Signs] 1 Semiconductor silicon wafer 3 Invalid area 4 Blade for dicing cut 12 Base glass

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/301 B24B 27/06 B28D 5/00

Claims (1)

(57) joining the Patent Claims 1. A semiconductor silicon wafer on pedestal glass, the bonded semiconductor silicon wafer / pedestal glass structure, and diced by a blade for dicing, the Semiconductor silicon wafer / pedestal gas
In a dicing and cutting method for a semiconductor wafer in which a lath structure is divided into a plurality of chips, a substantially square base glass is used as the pedestal glass, and the blade is vertically applied to an end surface of the square base glass. A dicing cut method for a semiconductor wafer.