JPH03120718A - Method for removing semiconductor wafer in chucking mechanism - Google Patents

Abstract

PURPOSE:To remove a semiconductor wafer without any damage to a semiconductor wafer finished face after grinding by a method wherein water containing numerous small bubbles in temporarily reserved in a slit of a chucking mechanism, the water containing numerous small bubbles damaging surface tension of static water is jetted to an upper face with a mount soaked and an entire lower face of the semiconductor wafer is uniformly floated. CONSTITUTION:By using a chucking mechanism 1 having vacuum suction, vacuum suction of an extremely thin semiconductor wafer A mounted on a mount 4 which has been subjected to grinding is released. At the same time water containing numerous small bubbles is jetted from an exhaust port commonly serving as an inlet port 3 and temporarily reserved in a slit 5. Water containing numerous small bubbles for damaging surface tension of a water layer made by a static state on the upper face of the mount 4 is jetted to the upper face of the mount 4 with the mount 4 soaked to have an entire lower face of the semiconductor wafer A floated uniformly, and the wafer A is sucked by a suction pat provided on a transfer arm and removed with the transfer arm lifted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for removing a brittle and extremely thin semiconductor wafer from a chuck mechanism of a grinding machine or the like.

[Background of the invention]

This type of semiconductor wafer according to the present invention is used in integrated circuits of electronic related equipment such as computers, so-called office automation equipment, etc., and the development thereof is progressing day by day, and as the equipment itself becomes smaller, it is becoming more and more extreme. From the viewpoints of thinner, ultra-high precision quality and workability, there is a growing demand for further diameter expansion.

[Prior art and its problems]

In a conventional mounting platform made of a porous material with a chuck mechanism that has a vacuum suction function such as a grinding machine, the semiconductor wafer is first vacuum suctioned and ground, and after the grinding process, the vacuum suction is released and air is released. The semiconductor wafer is transported backwards, floated up, adsorbed by a suction pad, and removed by raising the transfer arm, but air jets alone cannot remove fine particles such as grinding debris that adhere to the top surface of the mounting table. They cannot be removed sufficiently and remain on the top surface of the mounting table, etc., and if the semiconductor wafer is of normal thickness, the top surface of the semiconductor wafer will be distorted or damaged even if the semiconductor wafer is vacuum-adsorbed with some fine particles remaining. There were almost no problems such as

However, with the ultra-thin semiconductor wafers that are in demand these days, even if there is a slight amount of fine foreign matter such as grinding debris remaining on the top surface of the mounting table of the chuck mechanism, if vacuum suction is applied, the ultra-thin semiconductor wafers are brittle and may break. In some cases, the semiconductor wafer itself may be distorted by fine particles and the top surface to be ground cannot be flattened, or the top surface of the mirror-finished semiconductor wafer after grinding may be picked up with a suction pad and removed from the top surface of the chuck mechanism. Semiconductor wafers are often damaged due to the adsorption effect caused by the surface tension of the liquid adhering to the top surface of the mechanism, and since grinding is performed at high speed rotation, damage to semiconductor wafers is caused by frictional heat. Problems are emerging.

For this reason, a method has been adopted in which a separate cleaning device is used for cleaning each time after each grinding process, but this involves a large loss of time.

[Purpose of the invention]

In view of the above reasons, the present invention has been developed as a result of intensive research and has been developed to temporarily accumulate water containing a large amount of fine air bubbles in the gaps of these chuck mechanisms, thereby destroying the surface tension of water in a stationary state. Water containing microscopic air bubbles penetrates the mounting platform made of a porous material and is jetted onto the upper surface.The entire lower surface of the semiconductor wafer is evenly floated, and the suction pad provided on the transfer arm absorbs the water and the transfer arm is moved. The purpose is to provide a method for lifting and removing.

[Embodiments of the invention]

Three embodiments of the method for removing a semiconductor wafer in a chuck mechanism of a grinding machine or the like according to the present invention that achieves the above object will be described below with reference to the drawings.

FIG. 1 is a schematic explanatory diagram showing the main components of a part of the main body of a chuck mechanism of a grinding machine or the like according to the present invention, and FIG. It is a schematic explanatory diagram showing a floating state.

The present invention relates to a method for removing a brittle and ultra-thin semiconductor wafer A from a chuck mechanism 1 of a grinding machine, etc. The present invention relates to a method for removing a brittle and ultra-thin semiconductor wafer A from the chuck mechanism 1. In addition, a cylindrical recess 2 is formed in the chuck mechanism 1, and a gap 5 is provided at the bottom of the recess 2 to rotatably support a disc-shaped mounting base 4 made of a porous material. A chuck mechanism 1 having a vacuum suction function is used to grind an ultra-thin semiconductor wafer A which is fixed and has an exhaust port/water inlet 3 passing through the center of the shaft, and is placed on the mounting table 4. At the same time as the vacuum adsorption of the placed ultra-thin semiconductor wafer A after grinding is released, water containing a large amount of fine bubbles is jetted from the exhaust port/water inlet 3 and temporarily accumulates in the gap 5. The platform 4 made of a porous material is penetrated with water containing a large amount of fine air bubbles that destroys the surface tension of the water layer formed in a static state on the top surface of the platform 4. In this method, the entire lower surface of the semiconductor wafer A is uniformly floated by a jet on the upper surface, and the semiconductor wafer A is adsorbed by a suction pad provided on the transfer arm, and the transfer arm is raised and removed.

That is, the apparatus for carrying out the present invention is as shown in FIG.
A chuck mechanism main body 1 of a grinding machine or the like is formed with a recess 2 having a cylindrical shape and a flat bottom, and the bottom of the recess 2 and the lower surface of a mounting base 4 made of a porous material such as porous ceramic are connected. A gap 5 having an appropriate volume is provided in between, and the disk-shaped platform 4 is rotatably fixed to a shaft by means of forming a step, etc., and an exhaust port and inlet penetrating through the center of the shaft is provided. A water inlet 3 is provided, and the exhaust port/water inlet 3 passes through the chuck mechanism 1 and is connected to a vacuum pump and a water pump.The vacuum pump is operated to apply a load and vacuum adsorb the ultra-thin semiconductor wafer A. This is carried out using a device that includes a chuck mechanism 1 having a function and a transfer arm (not shown) provided with a suction pad at the tip on the upper side of the chuck mechanism 1 so as to be movable up and down.

At the same time, the vacuum suction of the ultra-thin semiconductor wafer A after the grinding process placed on the platform 4 made of a porous material is released, and at the same time, the water pump is operated from the exhaust port/water inlet 3 to remove a large amount of fine particles. When water containing air bubbles is jetted, the water containing fine air bubbles temporarily accumulates in the gap 5 having a volume, and when water continues to be fed further, the water containing a large amount of air bubbles flows into the gap 5. The water that fills the gap 5 and contains a large amount of microscopic bubbles at once permeates the platform 4 made of a porous material and is jetted onto the top surface of the platform 4, causing a static water layer to form on the top surface of the platform 4. It jets water containing a sufficient amount of fine air bubbles to break the tension, and by the large amount of fine air bubbles that permeate the platform 4 made of the porous material and a sufficient amount of water that flows out. The surface tension can be easily broken, and in addition, the entire lower surface of the semiconductor wafer A is evenly floated by the fine air bubbles and water, and is adsorbed by the suction pad provided on the transfer arm, and the transfer arm is lifted and removed. As a result, the extremely thin semiconductor wafer A can be removed without damage, and at the same time, the lower surface of the semiconductor wafer A and the upper surface of the chuck mechanism 1 are washed and cleaned with water, and at the same time, the frictional heat caused by the grinding is cooled.

In this way, the semiconductor wafer A is removed by jetting a large amount of microbubbles and a sufficient amount of water that easily destroys the surface tension of the water layer that forms in a stationary state, thereby safely and reliably removing the semiconductor wafer A without wasting time. The semiconductor wafer A that has been removed can be removed, the upper surfaces of the chuck mechanism 1 and the mounting table 4 are cleaned by a water stream, and the removed semiconductor wafer A is cooled without accumulating frictional heat caused by grinding. After transferring the first unground semiconductor wafer A to another system device, the first unground semiconductor wafer A is vacuum-adsorbed onto the upper surface of the chuck mechanism 1, which has been efficiently and sufficiently cleaned and freed from frictional heat, and can be ground sequentially. be.

〔Effect of the invention〕

As described above, the present invention not only allows removal of the semiconductor wafer after grinding without any loss of time and without causing any damage to the mirror surface of the semiconductor wafer, but also cleans the bottom surface of the semiconductor wafer and the top surface of the chuck mechanism. In addition, it can cool down the frictional heat caused by grinding.

The contribution it makes is immeasurable and has extremely significant effects.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing the main components of a part of a chuck mechanism main body of a grinding machine or the like according to the present invention. FIG. 2 is a schematic explanatory diagram showing a state in which a semiconductor wafer is floated by a water flow. 6A-Semiconductor wafer. 1-chuck mechanism, 2-recess, 3-exhaust port and water inlet, 4
- platform, 5- gap section; Figure 1 Figure 2

Claims (1)

[Claims] A transfer arm equipped with a suction pad at the tip is provided on the upper side of the chuck mechanism so as to be able to move up and down, and a cylindrical recess is formed in the chuck mechanism, and a gap is formed at the bottom of the recess. In order to grind ultra-thin semiconductor wafers, a disk-shaped platform made of a porous material is rotatably fixed on a shaft with a shaft, and an exhaust port and water injection port is provided passing through the center of the shaft. Using a chuck mechanism with a vacuum suction function, the vacuum suction of the ultra-thin semiconductor wafer placed on the mounting table after grinding is released, and at the same time, a large amount of fine air bubbles is contained from the exhaust port and water injection port. Water is jetted and temporarily accumulated in the gap, and water containing a large amount of microbubbles that breaks the surface tension of the water layer formed in a static state on the top surface of the platform is mounted on a vehicle made of a porous material. A chuck characterized in that the semiconductor wafer is infiltrated with the base and jetted onto the upper surface of the mounting base to evenly levitate the entire lower surface of the semiconductor wafer, and the semiconductor wafer is adsorbed by a suction pad provided on the transfer arm and removed by raising the transfer arm. A method for removing a semiconductor wafer in a mechanism.