KR19990057565A - Residual Charge Removal Device for Semiconductor Wafer Etching Equipment - Google Patents

Abstract

The present invention relates to a device for removing residual charge of a semiconductor wafer etching equipment. In the conventional art, a method of applying reverse bias has a negative electrode when the amount of negative bias supplied is greater than the amount of positive charge present in the electrostatic chuck. There is a possibility that it is charged, and the method using the plasma requires a lot of time due to various conditions such as supplying a predetermined RF power and a process gas to generate the plasma, and the productivity is degraded due to the positive charge in the plasma. By applying a physical damage (DAMAGE) to the electrostatic chuck to shorten the life, the present invention provides an electrostatic force to the etching chamber having a predetermined content and the wafer installed in the inner bottom of the etching chamber and introduced into the etching chamber In the etching equipment comprising an electrostatic chuck fixed with; A semiconductor wafer etching apparatus installed on one side of the etching chamber and having a filament emitting a large amount of hot electrons to neutralize the positive charge remaining in the electrostatic chuck, and a bias supply unit connected to the filament to supply a DC bias By providing a residual charge removing device of the present invention, the charge remaining in the electrostatic chuck can be easily and quickly removed by reacting the hot electrons with the positive charge remaining in the electrostatic chuck.

Description

Residual Charge Removal Device for Semiconductor Wafer Etching Equipment

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer etching equipment, and more particularly, to a device for removing residual charge of a semiconductor wafer etching equipment for removing charges remaining in an electrostatic chuck after an etching process is completed.

In general, a plasma etching process is performed by applying a photoresist to a semiconductor wafer, performing an exposure process using a patterned lattice, and performing a developing process to selectively remove the photoresist coated on the wafer, and then etching the wafer. The RF mixture is applied to the gas mixture in a state in which the electrostatic chuck is fixed to the inside and the process gas is supplied into the etching chamber. The gas mixture is dissociated to form a pattern on the wafer using the generated plasma.

On the other hand, if the wafer is separated from the electrostatic chuck after the etching process as described above and transferred to the next process, the charge supplied to fix the wafer remains in the electrostatic chuck.

As described above, a conventional apparatus for removing electric charge remaining in the electrostatic chuck is illustrated in FIG. 1.

1 is a cross-sectional view showing an etching apparatus having a residual charge removing device according to the prior art, as shown in the conventional etching equipment is a predetermined process gas supply line and a process gas discharge line (not shown) is connected to one side An etch chamber (1) having an internal volume thereof, an electrostatic chuck (2) provided at an inner front surface of the etch chamber (1) for supplying electric charges to electrically fix a wafer introduced into the etch chamber (1), A DC bias 3 connected to the bottom of the electrostatic chuck 2 and supplying a bias charged with a charge opposite to that supplied to the electrostatic chuck 2, and a ground connected to an upper side of the etching chamber 1. It consists of (4).

In the etching apparatus configured as described above, in order to remove the electric charge remaining in the electrostatic chuck 2 after the wafer is separated, the etching equipment remaining in the electrostatic chuck 2 remains in the DC bias 3 installed in the electrostatic chuck 2. A bias charged with ions and counter ions is applied to remove them by neutralizing their charges.

And, as shown in Figure 2, there is also a method for removing the charge remaining in the electrostatic chuck (2) is a method using a plasma (P), the etching process is the RF power in the etch chamber (1) is completed It is applied to form a plasma (P) that is dissociated into electrons, positive charges, neutrons and the like, and removes the positive charge remaining in the electrostatic chuck (2) through the ground (4) via the plasma (P) as a path.

However, in the conventional method of applying a reverse bias, the electrostatic chuck 2 may be charged to the cathode when the amount of negative bias supplied is greater than the amount of positive charge present in the electrostatic chuck 2. have.

In addition, in the method of using the plasma P, productivity is reduced due to severe time required due to various conditions such as supplying predetermined RF power and process gas to generate the plasma P, and plasma P There was a problem of shortening the life by applying physical damage (DAMAGE) to the electrostatic chuck (2) by the positive charge in the).

Accordingly, the present invention has been made to solve the above-described conventional problems, it is possible to easily and quickly remove the charge remaining in the electrostatic chuck, the remaining of the etching equipment for preventing damage to the electrostatic chuck Its purpose is to provide a charge removing device.

1 is a cross-sectional view showing an etching apparatus equipped with a residual charge removing device according to the prior art.

Figure 2 is a cross-sectional view showing another embodiment of the prior art.

Figure 3 is a cross-sectional view showing an etching apparatus equipped with a residual charge removal apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

10: etching chamber 11: electrostatic chuck

13 filament 14 bias supply

15: blocking film 16: blocking plate

17: drive motor 17a: drive shaft

In order to achieve the object of the present invention as described above, it comprises an etching chamber having a predetermined internal volume and an electrostatic chuck which is installed on the inner bottom of the etching chamber to fix the wafer introduced into the etching chamber with an electrostatic force In etching equipment; A semiconductor wafer etching apparatus installed on one side of the etching chamber and having a filament emitting a large amount of hot electrons to neutralize the positive charge remaining in the electrostatic chuck, and a bias supply unit connected to the filament to supply a DC bias A residual charge removal device of is provided.

Hereinafter, an embodiment of a residual charge removing apparatus of a semiconductor wafer etching apparatus according to the present invention will be described with reference to the accompanying drawings.

3 is a cross-sectional view showing an etching apparatus having a residual charge removing device according to the present invention, as shown in the drawing, the etching apparatus of the present invention has an etching chamber 10 having a predetermined content and the etching chamber 10 thereof. Electrostatic chuck (11) is provided on the inner bottom surface of the) to supply electric charge to electrically fix the wafer drawn into the etching chamber (10), and the ground (12) connected to the upper side of the etching chamber (10) And a filament 13 installed on one side of the etching chamber 10 to supply negative charge to the electrostatic chuck 11 after the etching process is progressed, and a bias supply unit to supply a DC bias to the filament 13. 14).

In addition, the outer surface of the filament 13 has several blocking films 15 formed vertically on the upper surface of the etching chamber 10 with the same length, and the blocking plate 16 having a predetermined area so as to be shielded on the bottom surface of the blocking film 15. ), The blocking plate 16 is formed to be rotatable by connecting to the drive shaft (17a) connected to the drive motor (17).

Referring to the operation of the residual charge removal device of the semiconductor wafer etching equipment according to the present invention configured as described above are as follows.

The filament 13 is shielded by the blocking film 15 and the blocking plate 16 and is subjected to the etching process without being exposed to the plasma, and after the predetermined etching process is performed, the electrostatic chuck 11 is subjected to electrostatic force. The fixed wafer is separated and transferred to the next process.

After the wafer is transferred as described above, a large amount of positive charge remains in the electrostatic chuck 11, in which the filament 13 is opened by rotating the blocking plate 16 by driving the driving motor 17. When a high-pressure DC bias is supplied to the filament 13 from the bias supply unit 14 installed on one side of the etching chamber 10, a large amount of hot electrons are generated in the filament 13.

The hot electrons generated as described above are neutralized with each other in response to the positive charge remaining in the electrostatic chuck 11, thereby removing the positive charge of the electrostatic chuck 11.

As described above, the residual charge removing device of the semiconductor wafer etching equipment according to the present invention is installed in a filament on one side of the etching chamber to react the hot electrons emitted from the filament with the positive charge remaining in the electrostatic chuck The charge remaining in the can be removed easily and quickly.

Claims (2)

An etching apparatus comprising an etching chamber having a predetermined content and an electrostatic chuck installed on an inner bottom surface of the etching chamber to fix the wafer introduced into the etching chamber with an electrostatic force; A semiconductor wafer etching apparatus installed on one side of the etching chamber and having a filament emitting a large amount of hot electrons to neutralize the positive charge remaining in the electrostatic chuck, and a bias supply unit connected to the filament to supply a DC bias Device for removing residual charge. The method of claim 1, wherein a barrier film made of an insulator is provided on an outer side of the filament, and a barrier plate is provided on the bottom surface of the filament to insulate the filament from plasma during an etching process. Device.