1. Field of the Invention
The present invention relates to a pressure control system, especially for a pressure control system of a wafer polishing apparatus.
2. Description of Related Art
As shown in
In order to making the pressure outputted from each of polishing heads to the wafer is high enough, ideally the pressure value inputted to each of the air pressure controlling devices 4a should be maintained to be 25 psi, so that the quality of polishing the wafer can be ensured. In fact because the branches 31a are connected with each other, leaping air phenomenon is happened between the air pressure controlling devices 4a and the pressure values of the air pressure controlling devices 4a are not the same, some pressure values are higher than 25 psi, and others are lower than 25 psi. When the pressure value of the air pressure controlling device 4a is lower than 25 psi, the wafer will leave out the wafer polishing apparatus. However, when the pressure value of the air pressure controlling device 4a is higher than 30 psi to exceed the rated pressure of the air pressure controlling device 4a, the air pressure controlling devices 4a is damaged and the life of the air pressure controlling device 4a is reduced.
Hence, the inventors of the present invention believe that the shortcomings described above are able to be improved and finally suggest the present invention which is of a reasonable design and is an effective improvement based on deep research and thought.
It is an object of the present invention to provide a pressure control system of a wafer polishing apparatus, and the pressure control system increase the yield of polishing wafers, and prevent the wafer polishing apparatus from being damaged.
To achieve the above object, the present invention provides a pressure control system of a wafer polishing apparatus. The pressure control system includes a main input air pressure regulator, an air branch conduit, a plurality of first pipes, a plurality of auxiliary air pressure regulators, a plurality of second pipes, and a plurality of air pressure controlling devices. The air branch conduit is connected with the main input air pressure regulator. The first pipes are connected between the air branch conduit and the auxiliary air pressure regulators. The second pipes are connected between the auxiliary air pressure regulators and the air pressure controlling devices.
The advantages of the present invention are described below: the auxiliary air pressure regulators can control the pressure of each of the second pipes, so that the air-leakage phenomenon is not happened between the air pressure controlling devices, and the stability of each of the air pressure controlling devices is higher and the yield of polishing wafers is increased. Besides, the auxiliary air pressure regulators can maintain the air pressure of each of the second pipes to be in the normal rated range, the auxiliary air pressure regulators can prevent the air pressure inputting to the air pressure controlling apparatus from being too high, so that increases the life of the air pressure controlling apparatus.
Refer to
Refer to
A first manometer 44 and a second manometer 45 are connected with the body 41, the first manometer 44 connects with the first pressure chamber 411, the second manometer 45 connects with the second pressure chamber 412, and the first manometer 44 and the second manometer 45 can display the air pressure of the first pressure chamber 411 and the air pressure of the second pressure chamber 412.
An upside of the body 41 is connected with a top cover 46, a receiving chamber 461 is mounted inside the top cover 46, a knob 47 is screwed with the upside of the top cover 46, wherein the knob 47 has a screw 471, the screw 471 is screwed with the upside of the top cover 46 and inserts into the receiving chamber 461. A second spring 462 is mounted inside the receiving chamber 461, a first washer 463 is connected between an upside of the second spring 462 and the screw 471, and the screw 471 presses on the first washer 463.
A colloid film 48 is arranged between an underside of the top cover 46 and the body 41, a second washer 481 is connected between an underside of second spring 462 and the colloid film 48, and the second spring 462 presses on the second washer 481.
When the knob 47 is rotated by a user, the screw 471 will press on the second spring 462, so that the vertical position of the second washer 481 can be controlled. When the pressure outputted from the second spring 462 which is up to the second washer 481 is higher than the air pressure of the first pressure chamber 411 and the air pressure of the second pressure chamber 412, the air valve 413 will be moved downwardly via the second spring 462 and the air hole 414 will be opened. On contrary, when the pressure outputted from the second spring 462 which is up to the second washer 481 is lower than the air pressure of the first pressure chamber 411 and the air pressure of the second pressure chamber 412, the air valve 413 will be moved upwardly via the first spring 4131 and the air hole 414 will be closed, so that the air pressure of second pressure chamber 412 can be regulated via controlling the state (open/close) of the air hole 414.
As shown in
As shown in
As shown in
The advantages of the pressure control system of the present invention are described below:
1. The auxiliary air pressure regulator 4 controls the pressure of each of the second pipes 5, so that the air-leakage phenomenon is not happened between the air pressure controlling apparatuses 6 via the auxiliary air pressure regulators 4, the auxiliary air pressure regulator 4 can control air pressure of each of the second pipes 5 to maintain to be in a steady state value, even if the air pressure outputted from the main input pressure regulator 1 is changed, the output pressure from the air pressure controlling apparatus 6 will not be changed seriously, so that the stability of each air pressure controlling apparatus 6 is higher and the yield of polishing wafers is increased.
2. The auxiliary air pressure regulator 4 controls the pressure of each of the second pipes 5, so that each of the air pressure controlling device 6 is capable of outputting enough pressure to the polishing head 7, so that the polishing head 7 can output enough pressure to the wafer and the wafer can't leave out the polishing apparatus during a polishing process.
3. The pressure of each of the second pipes 5 can be controlled in the rated pressure range of the air pressure controlling device 6, so that the auxiliary air pressure regulators 4 can prevent the pressure of each of the air pressure controlling apparatuses 6 from being too high, so that the life of each of the air pressure controlling apparatuses 6 can be increased.
What are disclosed above are only the specification and the drawings of the preferred embodiment of the present invention and it is therefore not intended that the present invention be limited to the particular embodiment disclosed. It will be understood by those skilled in the art that various equivalent changes may be made depending on the specification and the drawings of the present invention without departing from the scope of the present invention.
Number | Date | Country | Kind |
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98103972 | Feb 2009 | TW | national |