JP3318615B2 - Method of removing work in polishing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the manufacture of super LSIs and the like.
The present invention relates to a method of removing a workpiece, which is a semiconductor wafer serving as a substrate, from a base plate after polishing, and
More specifically, the present invention relates to a method for safely and securely removing a semiconductor wafer, which is a brittle, ultrathin, and large-diameter work, from a base plate.

[0002]

2. Description of the Related Art In a semiconductor wafer which is a work of this kind according to the present invention, electronic devices such as a computer,
A It is used for integrated circuits such as equipment, and its development is progressing day by day. Ultra thinness accompanying the miniaturization of equipment itself, ultra-high precision quality, and further expansion from the viewpoint of workability. A diameter is being required.

In addition, these semiconductor wafer devices are:
With the increase in density and the degree of integration, the production of ultra LSI (ULSI) of 64 megabytes or more has become necessary, and in recent years, the development of ultra LSI of 256 megabytes or 1 gigabyte has been started. .

On the surface of these semiconductor devices, a wiring layer (metal film), an insulating film (oxide film or the like) or a polysilicon film (semiconductor film) is formed as a multilayer film.
That is, super LSI against LSI is one story has a structure corresponding to the two-story, stories, producing odor
In need of polishing with a planar accuracy of the ultra-precision to each of the layers Te.

Conventionally, a base plate for holding a work of such a polishing machine or the like has a vacuum suction and a polishing treatment after the work is vacuumed, and the vacuum suction is released after the processing, thereby removing air. The semiconductor wafer is removed by feeding back, but a porous ceramic or a plate having many small holes must be used for the base plate, and the vacuum is maintained. In order to do so, they had to attach such devices.

[0006] In some cases, a holding member for holding the work between the base plate of the polishing machine is provided. However, the rotation of the base plate is temporarily stopped to mount and remove the work. It was time-consuming and inefficient.

[0007]

Therefore, the initial cost of the polishing apparatus itself is high, and therefore the polishing cost per VLSI is high. In -car, it has been desired to reduce the polishing cost per VLSI to the utmost and further increase the efficiency.

An object of the present invention is to use a soft plate for a base plate of a polishing machine, so that the work can be easily removed and the work can be provided at a low cost. The initial cost of the polisher in the process of manufacturing the polished material is drastically reduced.
It is an object of the present invention to significantly reduce the polishing cost per SI sheet.

[0009]

SUMMARY OF THE INVENTION A method of removing a work in a polishing machine according to the present invention is to form a small through hole for intermittently jetting a fluid to a base plate, and to form a base plate.
The outer periphery of the soft plate is attached to the plate, the non-polished surface of the work is attached to the soft plate with a liquid, and the work is sandwiched between the polishing plate and polished. After the work is polished, the base plate and the polishing plate are separated from each other by using a machine, and a liquid is jetted from the through-holes of the base plate to form a base plate and a soft plate. Forming a fluid storage portion between the flexible plate and the work, thereby expanding the soft plate to such an extent that the interfacial tension of the bonding surface between the soft plate and the work is destroyed. Is to be removed.

[0010]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of polishing a workpiece after polishing the workpiece.
The plate and the polishing plate are separated from each other.
The liquid is jetted from the through-holes of the plate to form a fluid reservoir between the base plate and the soft plate, so that the adhesive surface between the soft plate and the work is formed. The work is removed by expanding the soft plate to such an extent that the interfacial tension is destroyed.

[0011]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic side view illustrating a base plate of a polishing machine according to an embodiment of the present invention, and FIG. 2 is a schematic side view illustrating a method of removing a work according to the embodiment.

According to the present invention, a workpiece W, which is a semiconductor wafer serving as a substrate in a manufacturing process of an VLSI or the like, is polished and then a base plate is formed thereon.
More specifically, the present invention relates to a method for safely and securely removing a semiconductor wafer which is a brittle, ultra-thin, and enlarged diameter of a work W. A through hole 2 for intermittently jetting fluid is formed in a substantially central side of a base plate 1 mounted on a rotating shaft, and a soft member formed of a soft member is formed in the base plate 1. The outer periphery of the plate 3 is adhered, and the non-polished surface of the work W is adhered to the soft plate 3 with a liquid.
After the work W is polished, the work W is polished using a polishing machine that nips the work W with a polishing plate mounted on the other rotating shaft.
The plate 1 and the polishing plate are separated from each other, a fluid is jetted from the small through hole 2 of the base plate 1, and a fluid is stored between the base plate 1 and the soft plate 3. By removing the work W by expanding the soft plate 3 to such an extent as to break the interfacial tension of the bonding surface between the soft plate 3 and the work W by forming the portion A. It is.

The work W to be removed by the detaching method of the present invention is a semiconductor wafer, and one surface of the semiconductor wafer is provided with an insulating film, a wiring layer, and a polysilicon by a method such as photolithography, epitaxial growth, or aluminum evaporation. A silicon film and the like are formed, and furthermore, in a super LSI, these steps are repeated and laminated. However, in forming each layer, polishing of a flat surface with extremely high precision is required each time. is there.

That is, the embodiment of the present invention is applied to a polishing machine.
More specifically, the polishing machine is a polishing machine that is attached to a polishing cloth (not shown) such as non-woven fabric, natural or artificial leather, and is attached to a rotating shaft that is rotated by one driving source. And a base plate made of alumina ceramic or the like mounted on a rotating shaft (not shown) rotated by the other driving source while holding the work W opposite the polishing plate. -G1
The non-polished surface of the semiconductor wafer, which is the work W, is held toward the base plate 1 and the polished surface such as an insulating film is polished by a polishing cloth.

According to the present invention, a small through hole 2 for intermittently jetting a fluid is formed in a substantially central side of the base plate 1, and the small through hole 2 is a liquid such as pure water. Alternatively, it is connected to a driving source such as a pump of a gas such as air, a piston cylinder, or the like, and is jetted.

Next, the outer periphery of the soft plate 3 formed of a soft member such as a silicone resin is adhered to the base plate 1 with an adhesive, an adhesive or the like. The non-polished surface of the work W is adhered to the port 3 with a liquid such as pure water.

The work W is polished by stretching a polishing cloth and sandwiching the work W with a polishing plate (not shown) axially mounted on the other rotating shaft.

In the removing method of the present invention, the base plate 1 and the polishing plate are separated from each other after the work W is polished using the polishing machine configured as described above. For example, pure water is jetted to form a fluid reservoir A made of pure water between the base plate 1 and the soft plate 3, and the fluid reservoir A has the soft plate 3 adhered to the base plate 1. which it was made possible by a soft by fluid jets
The central side of the plate 3 slightly swells toward the work W.

By forming the fluid storage portion A, the soft plate 3 bends and bulges due to the material characteristics, and the adhesive surface between the soft plate 3 and the work W with a liquid such as pure water. The work W comes off by destroying the interfacial tension.

In the embodiment, the control ring 4 is adhered to the outer periphery so as to enclose the work W. That is, the top surface of the control ring 4 is slightly lower than the polished surface of the work W. The polishing surface of the work W being polished has a slight height such that it does not contact when the polishing surface of the work W and the polishing cloth are in a parallel state, but does contact when the polishing cloth is in a non-parallel state. Especially, only the edges are prevented from being sharply polished.

[0022]

As described above, according to the present invention, a brittle, ultra-thin, and large-diameter semiconductor wafer, which is a work in the process of manufacturing an VLSI, can be produced without causing a time loss. It can be removed without causing any obstacles to the mirror surface after processing. By using a base plate on which a soft plate is adhered, the work can be adhered with pure water and easily. The initial cost of the polishing machine can be reduced, the polishing cost per VLSI can be reduced, and its contribution is immeasurable. To play.

[Brief description of the drawings]

FIG. 1 is a view showing a base plate of a polishing machine according to an embodiment of the present invention.
FIG.

FIG. 2 is a schematic side view illustrating a method of removing a work according to the embodiment.

[Explanation of symbols]

 W Work A Fluid storage section B Air inflow section 1 Base plate 2 Through-hole 3 Soft plate 4 Control ring

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/304 B24B 37/04 B24B 41/06 B65G 49/07 H01L 21/68

Claims (1)

(57) [Claims] A through hole for intermittently jetting a fluid is formed in a substantially central side of a base plate axially mounted on one of the rotating shafts, and a soft member is formed in the base plate. Attach the outer periphery of the formed soft plate and apply the heat to the soft plate.
The non-polishing surface of the workpiece is affixed with a liquid, and the workpiece is polished using a polishing machine that polishes the workpiece by sandwiching the workpiece with a polishing plate axially mounted on the other rotating shaft. The base plate and the polishing plate are separated from each other, and a liquid is jetted from the through-holes of the base plate to form a fluid reservoir between the base plate and the soft plate. The work in the polishing machine is characterized in that the soft plate is swollen to such an extent that the interfacial tension of the bonding surface between the soft plate and the work is destroyed and the work is removed. -How to remove the hook.