Vacuum pump exhaust pipe of chemical vapor deposition apparatus and relevant vacuum pump

Disclosed is a vacuum pump exhaust pipe of a chemical vapor deposition apparatus, wherein two ports of the vacuum pump exhaust pipe are respectively connected to a vacuum pump outlet and a scrubber, and anti-sticking inner pipes are installed inside the exhaust pipe and closely contacted with inner walls of the exhaust pipe. The present invention also relates to a vacuum pump of the chemical vapor deposition apparatus. Blockage hardly occurs in the vacuum pump exhaust pipe of the chemical vapor deposition apparatus and the relevant vacuum pump according to the present invention to solve problems of the easily found blockage in the exhaust pipe, wasting the manpower and the time for clearing the exhaust pipe and the effect to the uptime of the chemical vapor deposition apparatus in the prior arts.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a semiconductor manufacture field, and more particularly to a vacuum pump exhaust pipe of a chemical vapor deposition apparatus and a relevant vacuum pump capable of extending the preventive maintenance cycle of the apparatus.

2. Description of Prior Art

A plasma-enhanced chemical vapor deposition apparatus is in charge of vapor depositions for forming plural thin film layers in a thin film transistor. As shown inFIG. 1, a reaction chamber of the plasma-enhanced chemical vapor deposition apparatus is denoted by100. A vacuum pump is denoted by200. A vacuum pump exhaust pipe is denoted by300. A scrubber is denoted by400. In the deposition process, the thin film is not merely formed on a surface of a substrate but also on the inner wall of the reaction chamber100. The non-reacted gases are vented to the scrubber400by the vacuum pump200for burning process. In the entire chemical vapor deposition process, the usage percentage of the total gases is less then 10% and a large amount of non-reacted gases are vented. As the exhaust gases are vented to the outlet of the vacuum pump200, the pressure here rises to 600 Pascal and temperature here drops to 100 degree Celsius. The density of O2rapidly ascends. The components of the exhaust gases can be SiH4, H2, N2, NH3and etc. The exhaust gases may react with each other or with the inner wall to generate byproduct powders. Such byproduct powders can block the vacuum pump exhaust pipe300at the outlet of the vacuum pump200. Therefore, the vacuum pump exhaust pipe300at the outlet of the vacuum pump200cannot vent gases fluently and causes alarms to the main apparatus and abandoned products. The procedure of dealing the blockage in the exhaust pipe300at the outlet of the vacuum pump200is: removing the exhaust pipe300at the outlet of the vacuum pump200every two weeks. The exhaust pipe300is cleaned with water, dried and then re-installed. The whole preventive maintenance needs two men operations and the pipe cleaning procedure for one reaction chamber takes one hour. The manpower and the time are wasted and the uptime of the chemical vapor deposition apparatus is affected.

Consequently, there is a need to provide a vacuum pump exhaust pipe of a chemical vapor deposition apparatus and a relevant vacuum pump to solve the existing problems of prior arts.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide a vacuum pump exhaust pipe of a chemical vapor deposition apparatus and a relevant vacuum pump which blockage hardly occurs to solve problems of the easily found blockage in the exhaust pipe, wasting the manpower and the time for clearing the exhaust pipe and the effect to the uptime of a plasma-enhanced chemical vapor deposition apparatus in the prior arts.

The present invention relates to a vacuum pump exhaust pipe of a chemical vapor deposition apparatus, wherein two ports of the vacuum pump exhaust pipe are respectively connected to a vacuum pump outlet and a scrubber. Anti-sticking inner pipes are installed inside the exhaust pipe and closely contacted with inner walls of the exhaust pipe. A material of the anti-sticking inner pipes is Polytetrafluoroethene. The anti-sticking inner pipes are installed at a joint of the vacuum pump outlet and the exhaust pipe and at a joint of the scrubber and the exhaust pipe. Outer surfaces of portions of the exhaust pipe which are not installed with the anti-sticking inner pipes are attached with heating tapes.

The present invention also relates to a vacuum pump exhaust pipe of a chemical vapor deposition apparatus, wherein two ports of the vacuum pump exhaust pipe are respectively connected to a vacuum pump outlet and a scrubber, characterized in that anti-sticking inner pipes are installed inside the exhaust pipe and closely contacted with inner walls of the exhaust pipe.

In one embodiment of the present invention, a material of the anti-sticking inner pipes is Polytetrafluoroethene.

In one embodiment of the present invention, the anti-sticking inner pipe is installed at a joint of the vacuum pump outlet and the exhaust pipe.

In one embodiment of the present invention, the anti-sticking inner pipe is installed at a joint of the scrubber and the exhaust pipe.

In one embodiment of the present invention, the anti-sticking inner pipes are installed at a joint of the vacuum pump outlet and the exhaust pipe and at a joint of the scrubber and the exhaust pipe at the same time.

In one embodiment of the present invention, outer surfaces of portions of the exhaust pipe which are not installed with the anti-sticking inner pipe are attached with heating tapes.

The present invention also relates to a vacuum pump of a chemical vapor deposition apparatus, wherein two ports of the vacuum pump are respectively connected to an outlet of the chemical vapor deposition apparatus and a scrubber. The vacuum pump comprises an exhaust pipe connected to the scrubber. Anti-sticking inner pipes are installed inside the exhaust pipe and closely contacted with inner walls of the exhaust pipe. A material of the anti-sticking inner pipes is Polytetrafluoroethene.

In one embodiment of the present invention, the anti-sticking inner pipes are installed at a joint of the vacuum pump outlet and the exhaust pipe and at a joint of the scrubber and the exhaust pipe.

The one embodiment of the present invention, the anti-sticking inner pipe is installed at a joint of the vacuum pump outlet and the exhaust pipe.

In one embodiment of the present invention, the anti-sticking inner pipe is installed at a joint of the scrubber and the exhaust pipe.

In one embodiment of the present invention, outer surfaces of portions of the exhaust pipe which are not installed with the anti-sticking inner pipe are attached with heating tapes.

In one embodiment of the present invention, the anti-sticking inner pipes are installed at all the inner walls of the exhaust pipe.

Comparing with the vacuum pump exhaust pipe of the chemical vapor deposition apparatus in the prior arts with problems of the easily found blockage in the exhaust pipe, wasting the manpower and the time for clearing the exhaust pipe and the effect to the uptime of the plasma-enhanced chemical vapor deposition apparatus, the vacuum pump exhaust pipe of the chemical vapor deposition apparatus and the relevant vacuum pump employ the Polytetrafluoroethene anti-sticking inner pipes to prohibit blockage in the exhaust pipe formed by the exhaust gases from the chemical vapor deposition apparatus. Accordingly, the drawbacks of the prior arts can be prevented.

For a better understanding of the aforementioned content of the present invention, preferable embodiments are illustrated in accordance with the attached figures for further explanation:

DETAILED DESCRIPTION OF THE INVENTION

The following descriptions for the respective embodiments are specific embodiments capable of being implemented for illustrations of the present invention with referring to appended figures. For example, the terms of up, down, front, rear, left, right, interior, exterior, side, etcetera are merely directions of referring to appended figures. Therefore, the wordings of directions are employed for explaining and understanding the present invention but not limitations thereto.

In figures, the elements with similar structures are indicated by the same number.

FIG. 2depicts a connection diagram of a vacuum pump exhaust pipe of a chemical vapor deposition apparatus according to a preferable embodiment of the present invention. As described in prior art section, as the plasma-enhanced chemical vapor deposition apparatus is performing etching and filming processes, the flow of the reaction gases are facility supplies—gas tanks—gas source terminals—reaction chamber100—vacuum pump200—scrubber400—atmosphere and a whole flow is completed. The vacuum pump200is connected to the scrubber400with an exhaust pipe300. In the whole flow of reaction gases, the gas flow environment is under high degree of vacuum and low pressure from the facility supplies to the vacuum pump200without the effect of the external environment. After exhaust gases generated in the reaction chamber100are vented to the exhaust pipe300behind the vacuum pump200, the degree of vacuum descends. The densities of the exhaust gases ascend and the density of the O2rapidly ascends, too. Moreover, the exhaust pipe300is exposed to contact with the external environment with a lower temperature. Therefore, powder particles can be easily formed on the inner walls of the exhaust pipe300and the blockage of the exhaust pipe300happens as time passed, ultimately.

As shown inFIG. 3andFIG. 4, anti-sticking inner pipes310are installed inside the exhaust pipe300and closely contacted with inner walls of the exhaust pipe300. The material of the anti-sticking inner pipes310is preferably to be Polytetrafluoroethene. Polytetrafluoroethene is a macromolecular compound polymerized by Tetrafluoroethene. The Polytetrafluoroethene has advantages of excellent chemical stability, resistant to corrosion, sealing performance, anti-sticking, electric insulation and ageing resistance. The excellent chemical stability of the Polytetrafluoroethene allows the anti-sticking inner pipes310not to react with any exhaust gases. The anti-sticking property of the Polytetrafluoroethene makes the anti-sticking inner pipes310with bad adhesion. The inner walls of the anti-sticking inner pipes310are hardly adhered by any powder particles generated in the anti-sticking inner pipes310. The powder particles are easily inhaled by the scrubber400. Therefore, blockage hardly happens to the exhaust pipe300with the anti-sticking inner pipes310and the manpower and the time of cleaning the exhaust pipe300can be saved and the effect to the uptime of the plasma-enhanced chemical vapor deposition apparatus can be reduced. Other anti-sticking material also can be illustrated for the anti-sticking inner pipes310.

As shown inFIG. 2, a vacuum pump exhaust pipe of a chemical vapor deposition apparatus according to a first preferable embodiment of the present invention is illustrated. The anti-sticking inner pipe310is installed at a joint of the outlet of the vacuum pump200and the exhaust pipe300. As shown in the area10ofFIG. 2, only the outlet of the vacuum pump200is installed with the anti-sticking inner pipe310. The densities of the exhaust gases are in maximum and most of the powder particles are generated in the area10because the pressure ascension here is most distinct. The anti-sticking inner pipe310installed at the area10can most efficiently decrease the powder particle accumulations in the exhaust pipe300, and more particularly to prevent the powder particle accumulations at the joint of the vacuum pump outlet and the exhaust pipe300. Meanwhile, the cost of manufacturing and installing the anti-sticking inner pipe310is in minimum.

As shown inFIG. 2, a vacuum pump exhaust pipe of a chemical vapor deposition apparatus according to a second preferable embodiment of the present invention is illustrated. The anti-sticking inner pipe310is installed at a joint of the scrubber400and the exhaust pipe300. As shown in the area30ofFIG. 2, only the outlet of the exhaust pipe300is installed with the anti-sticking inner pipe310. The pressure of the exhaust gases rises further because the exhaust gases from the exhaust pipe300is entering the scrubber400here. The powder particles here are generated easier than in the middle of the exhaust pipe300(such as the area20). Therefore, the anti-sticking inner pipe310installed in the area30can decrease the powder particle accumulations better, and particularly decrease the powder particle accumulations in the joint at the scrubber400and the exhaust pipe300. The manufacture and installation cost of the anti-sticking inner pipe310is similar to that of the first preferable embodiment.

As shown inFIG. 2, a vacuum pump exhaust pipe of a chemical vapor deposition apparatus according to a third preferable embodiment of the present invention is illustrated. The anti-sticking inner pipes310are installed at a joint of the outlet of the vacuum pump200and the exhaust pipe300and at a joint of the scrubber400and the exhaust pipe300at the same time. The concrete effects can be referred to the descriptions in the foregoing first and second embodiments. Because the sequence of the blockage degree of the exhaust pipe300is area10>area30>area20, the effects of the blockages at the area10and area30are most serious. Meanwhile, manufacturing and installing the anti-sticking inner pipes310in the area10and area30is easier and the cost is lower. Therefore, installing the anti-sticking inner pipes310in the area10and area30at the same time in this embodiment can achieve the best effect of preventing blockage without adding a high cost.

As shown inFIG. 2, a vacuum pump exhaust pipe of a chemical vapor deposition apparatus according to a fourth preferable embodiment of the present invention is illustrated. Outer surfaces of portions of the exhaust pipe300which are not installed with the anti-sticking inner pipes310are attached with heating tapes. The reason of the powder particle accumulations in the anti-sticking inner pipes310and the exhaust pipe300is caused by the pressure rise and the temperature difference between the exhaust pipe300and the exhaust gases. While one or two ports (area10or/and area30) of the exhaust pipe300are installed the anti-sticking inner pipes310inside, in the areas where the anti-sticking inner pipes310cannot be installed or the installation cost is higher, and particularly in the middle of the exhaust pipe300(area20), the heating tapes are attached to the outer surfaces of the exhaust pipe300in these positions for heating the exhaust pipe300. By decreasing the temperature difference between the exhaust pipe300and the exhaust gases, the powder particle accumulations on the inner walls of the exhaust pipe300can be decreased where the anti-sticking inner pipes310are not installed. Accordingly, the preventive maintenance cycle of the whole exhaust pipe300can be extended to reduce the effect to the uptime of a plasma-enhanced chemical vapor deposition apparatus.

In a vacuum pump exhaust pipe of a chemical vapor deposition apparatus according to the fifth preferable embodiment of the present invention, the anti-sticking inner pipes310are installed at all the inner walls of the exhaust pipe300. In this embodiment, all the inner walls of the exhaust pipe300are installed with the anti-sticking inner pipes310to maximatily extend the preventive maintenance cycle of the whole exhaust pipe300and to reduce the effect to the uptime of a plasma-enhanced chemical vapor deposition apparatus. However, the anti-sticking inner pipes310are installed in the middle (area20) of the exhaust pipe300, the difficulty level and the cost are both high.

Before the anti-sticking inner pipes310are installed inside the vacuum pump exhaust pipe of the chemical vapor deposition apparatus according to the present invention, the pipes of the Polytetrafluoroethene material are machine-shaped as being the anti-sticking inner pipes310and installed at the relevant positions of the exhaust pipe300where need to be protected. It is required that the outer diameter of the anti-sticking inner pipe310needs to be fit with the inner diameter of the exhaust pipe300to guarantee the smooth exhaust for sure. Meanwhile, the thickness of the anti-sticking inner pipe310is preferably to be 1 mm-3 mm. The better venting effect can be guaranteed and the best preventing effect to the powder particle accumulations can be achieved. The lengths of the anti-sticking inner pipes310are determined by the lengths of the exhaust pipe300and the relevant demands for the positions of installing the anti-sticking inner pipes310.

The present invention also relates to a vacuum pump of a chemical vapor deposition apparatus, wherein two ports of the vacuum pump are respectively connected to an outlet of the chemical vapor deposition apparatus and a scrubber. The vacuum pump comprises an exhaust pipe connected to the scrubber. Anti-sticking inner pipes are installed inside the exhaust pipe and closely contacted with inner walls of the exhaust pipe. A material of the anti-sticking inner pipes is Polytetrafluoroethene. The anti-sticking inner pipes are installed at a joint of the vacuum pump outlet and the exhaust pipe and/or at a joint of the scrubber and the exhaust pipe. Alternatively, the anti-sticking inner pipes are installed at all the inner walls of the exhaust pipe.

The benefits and specific embodiments of the vacuum pump of the chemical vapor deposition apparatus are the same or similar to those of the vacuum pump exhaust pipe of the chemical vapor deposition apparatus. Please refer to the specific embodiments of the vacuum pump exhaust pipe of the chemical vapor deposition apparatus for specific details.