KR20080051838A - Particle removing apparatus and method of epitaxial equipment with n2 purge nozzle - Google Patents

Abstract

An apparatus and a method for removing particles with an N2 purge nozzle in epitaxial equipment are provided to reduce particles due to the supplying of N2 gas by installing the N2 purge nozzle in a load lock chamber. A wafer cassette is placed on a load lock chamber. A wafer handling chamber is connected to a side of the load lock chamber. A process chamber is connected to the other side of the wafer handling chamber. A wafer transfer arm is installed on a center section in the wafer handling chamber. A wand is connected to an end of the wafer transfer arm. An N2 purge nozzle is installed on an upper portion in the load lock chamber. A circular plate(74) is located on a lower end of the N2 purge nozzle. Radial spray holes(75) are prepared on the circular plate centering a straight low end of the nozzle at regular intervals.

Description

Particle removal apparatus and method of epitaxial equipment with N2 PURGE NOZZLE}

1 is a perspective view of a main portion of the epitaxial equipment for handling a wafer using a conventional wand,

2 is a schematic diagram showing a wafer transfer arm and wand of a conventional epitaxial equipment;

3 is a view illustrating particle generation by N2 when a wand enters a conventional load lock chamber;

4 is a diagram showing the number of particles and crystals generated by conventional cassette slots;

5 is a view showing a form after mounting the conventional load lock chamber and the present invention N2 purge nozzle in the load lock chamber,

6 is a view showing a round plate seen from below,

Fig. 7 is a chart showing changes in defect density before and after performing an N2 purge.

* Description of the symbols for the main parts of the drawings *

10 load lock chamber 11 wafer cassette

12 elevator 20 wafer handling chamber

30: process chamber 31: gate valve

40: wafer transfer arm 41: rotation unit

42: arm unit 50: wand

51: blade unit 51a: suction port

51b: discharge port 52: foot unit

60 wafer 70 N2 purge nozzle

71: support portion 72: vent line

73: N2 purge line 74: round plate

75: injection hole

The present invention relates to an apparatus and method for removing particles using N2 purge nozzles of epitaxial equipment.

In general, the single crystal silicon deposition process in the manufacturing process of the semiconductor device has become one of the core process that is applicable to not only the memory semiconductor, but also non-memory semiconductor. Epi-wafer development and selective epitaxial growth of silicon (SEG) are typical processes.

Conventional techniques for single crystal silicon deposition are divided into low pressure chemical vapor deposition (LPCVD) and ultra high vacuum chemical vapor deposition (UHV-CVD). The LPCVD method is simple in process and has good productivity for epi-wafer fabrication, but is limited by the high thermal budget of 800 ° C. or higher to apply the SEG process.

The epitaxial device is mainly used in an initial process during a manufacturing process of a semiconductor device, and is used to form an identical layer having the same lattice structure on a wafer.

1 is a perspective view of a main portion of an epitaxial device for handling a wafer using a conventional wand. Here, the wand 50 refers to the Bernoulli principle (the principle that the pressure is low when the fluid velocity is high, and the pressure is high when the velocity is slow) to adjust the speed and pressure of the fluid to move the wafer 60 without lifting it directly. Refers to a feeder that can

As shown in FIG. 1, the epitaxial equipment for handling a wafer using a conventional wand includes a loadlock chamber 10, a wafer handling chamber 20, a process chamber, and a process chamber. 30), a wafer transfer arm 40 and a wand 50.

The load lock chamber 10 is a chamber in which the wafer 60 enters into the epitaxial equipment from a SMIF (Standard Mechanical Interface, a kind of wafer transfer device, not shown).

The wafer handling chamber 20 is a chamber located between the load lock chamber 10 and the process chamber 30, and the wafer 60 is moved by the wafer transfer arm 40 and the wand 50 located at the center of the chamber. Transferred. In addition, the process chamber 30 is a chamber located in connection with the wafer handling chamber 20, and is a chamber in which an epitaxial process is performed.

The wafer transfer arm 40 includes a rotating unit 41 installed at a central portion of the wafer handling chamber 20, and one end of which is connected to the rotating unit 41 and the other end of which is connected to the wand 50. It is comprised by the unit 42, The conveyance of the wafer 60 is performed by the rotational motion and linear motion of the wand 50. As shown in FIG.

A process of transferring a conventional wafer for process progress is as follows.

The wafer cassette 11 is first loaded from the SMIF into the load lock chamber 10. Then, when the elevator 12 of the load lock chamber 10 descends and moves to the # 01 slot position (indicating the first slot position number where the wafer 60 is stored in the wafer cassette 11), the wand 50 is # 01 is located on the upper surface of the wafer 60 in the slot position.

Since the supply of nitrogen gas connected to the wand 50 is turned on, the wafer 60 is lifted by the wand 50, and the wand 50 moves to the wafer handling chamber 20 and is then processed by a rotational motion. When positioned in front of the gate valve 31 of the chamber 30, the gate valve 31 is opened and the wand 50 moves into the process chamber 30.

Since the supply of nitrogen gas connected to the wand 50 is turned off, the wafer 60 is placed on the upper surface of the susceptor of the process chamber 30, and the wand 50 is returned to the wafer handling chamber 20. When the gate valve 31 is closed after the movement, the process proceeds.

When the process is completed, the gate valve 31 is opened and the wand 50 moves to the process chamber 30 to convey the wafer 60 back to the slot position # 01 of the load lock chamber 10.

This process is repeated for all the wafers 60 in the slot positions # 1 to #N of the wafer cassette 11 in the load lock chamber 10, and then the wafer cassette 11 is unloaded with SMIF. .

2 is a schematic diagram showing a wafer transfer arm and wand of a conventional epitaxial device.

As shown in FIG. 2, the wand 50 includes a blade unit 51 which fixes the wafer 60 by a vacuum formed at a bottom thereof, and the fixed wafer 60 moves in the direction of the wafer transfer arm 40. The foot unit 52 which prevents it from being prevented, the suction port 51a formed in the center of the bottom face of the said blade unit 51, and the seven discharge ports 51b formed surrounding the said suction port 51a are formed.

Therefore, the wand 50 is located on the upper surface of the wafer 60, and the vacuum generated as the nitrogen gas discharged from the seven discharge ports 51b is strongly sucked into the suction port 51a. Hatched portion) to maintain a constant pressure equilibrium between the discharge and suction of the gas and to fix the wafer 60 without contact with the bottom surface of the blade unit 51 of the wand 50 to prevent damage to the wafer 60 You can do it.

3 is a view illustrating particle generation by N2 when a wand enters a conventional load lock chamber. 3 (a), 3 (b) and 3 (c) are located on the upper surface of the wafer 60 on which the wand 50 is placed on the wafer cassette 11 while the elevator 12 descends to lift the wafer 60. In the process, N2 gas is supplied and particles are generated.

4 is a diagram showing the number of particles and crystals generated by each cassette slot.

4 (a) shows the distribution of particles and crystals in the # 5, # 10, # 22, and # 23 slots, respectively. It is shown. The horizontal axis in the diagram represents the wafer slot number, and the vertical axis represents the number of particles and crystals generated.

As described above, according to the wafer fixing method using the wand 50, particles are generated while strong N2 is generated in the wand 50 to use the Bernoulli principle when the wafer 60 is transferred to the load lock chamber 10. Particles generated in the process chamber 30 easily contaminate the wafer surface and the contamination of the particles also occurs in other parts of the equipment, such as the load lock chamber 10 or the wafer handling chamber 20, as the wafers are transported. have.

The present invention has been made to solve the above-mentioned problems, and provides an apparatus and method for removing particles using the N2 purge nozzle of epitaxial equipment that can reduce the particle generation in the epitaxial equipment handling the wafer using a wand. Has its purpose.

Particle removal apparatus using the N2 purge nozzle of the present invention epitaxial equipment for achieving the above object, in the epitaxial equipment for forming the same layer having the same lattice structure on the wafer for semiconductor manufacturing, the wafer cassette is A load lock chamber placed; A wafer handling chamber connected to a side of the load lock chamber; A process chamber connected with the other side of the wafer handling chamber; A wafer transfer arm installed at an inner center of the wafer handling chamber; And a wand connected to one end of the wafer transfer arm; and an N2 purge nozzle installed at an inner upper end of the load lock chamber.

Particle removal method using the N2 purge nozzle of the epitaxial device of the present invention, epitaxial equipment for forming the same layer having the same lattice structure on the wafer for semiconductor manufacturing, the loading step of placing the wafer cassette in the load lock chamber, the A first transfer step of transferring the wafer stored in the wafer cassette to the process chamber, a process step of proceeding the process in the process chamber, a second transfer step of transferring the wafer to the load lock chamber after the process step, in the load lock chamber Characterized in that the purge step of removing the particles by the N2 purge nozzle.

Hereinafter, the configuration and operation of the preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The particle removal apparatus of the epitaxial equipment for semiconductor manufacturing according to an embodiment of the present invention is a load lock chamber 10, a wafer handling chamber 20, a process chamber 30, a wafer transfer, as in the conventional apparatus shown in FIG. The arm 40 and the wand 50 are included, and the following description will be mainly focused on the operation of newly added components.

FIG. 5: is a figure which shows the form before installation (FIG. 5 (a)) and the post-installation form (FIG. 5 (b)) of the N2 purge nozzle in the load lock chamber 10. As shown in FIG.

Particle removal apparatus using the N2 purge nozzle of the epitaxial equipment according to an embodiment of the present invention is to include the N2 purge nozzle 70 of Figure 5 (b).

The N2 purge nozzle 70 is attached to the inner upper end of the load lock chamber 10 and serves to remove particles such as powder present on the surface of the wafer 60 where the process is completed.

As shown in FIG. 5B, the present invention includes an N2 purge nozzle 70, a support 71, a vent line 72, an N2 purge line 73, and a circular plate 74 in the load lock chamber 10. ).

Among the above-described components, the supporting part 71 serves to support the wafer 60 placed on the upper surface, and the vent line 72 has particles with the purge gas present in the load lock chamber 10. It serves as an exit exit, the purge line 73 serves to supply the N2 gas to the N2 purge nozzle 70, the circular plate 74 is the N2 gas injected from the N2 purge nozzle 70 6 serves to evenly spray on the wafer 60 through the injection hole 75 shown in FIG.

Therefore, particles such as powder present on the surface of the wafer 60 having completed the process are separated from the surface of the wafer by the N2 purge gas injected through the N2 purge nozzle 70 connected to the N2 purge line 73 and the vent Is discharged to line 72.

Particle removal method using the N2 purge nozzle of the epitaxial equipment according to another embodiment of the present invention is composed of a loading step, a first transfer step, a process step, a second transfer step, a purge step, below each step It is detailed.

The loading step is a step in which the wafer cassette 11 on which the wafer 60 is seated is placed in the load lock chamber 10. For example, the wafer cassette 11 is loaded by the operator or the SMIF robot from the SMIF into the load lock chamber 10.

In the first conveyance step, when the elevator 12 of the load lock chamber 10 descends and moves to the # 01 slot position after completion of the loading step, the wand 50 moves to the upper surface of the wafer 60 at the # 01 slot position. Located. Since the supply of nitrogen gas connected to the wand 50 is turned on, the wafer 60 is lifted by the wand 50, and the wand 50 moves to the wafer handling chamber 20 and is then processed by a rotational motion. Located in front of the gate valve 31 of the chamber (30). After the gate valve 31 is opened and the wand 50 moves into the process chamber 30, the supply of nitrogen gas connected to the wand 50 is turned off, so that the wafer 60 is turned on the top surface of the susceptor of the process chamber 30. Wand 50 is moved back to the wafer handling chamber 20 and the gate valve 31 is closed.

The process step is a step of forming the same layer having the same lattice structure as the wafer 60 on the surface of the wafer 60 placed on the susceptor.

In the second conveyance step, when the process step is completed, the gate valve 31 is opened and the wand 50 moves to the process chamber 30 to convey the wafer 60 to the load lock chamber 10. In this step, in the process of fixing the wafer 60 to the bottom surface of the wand 50 by the wand 50, particles generated in the process chamber 30 contaminate the upper surface of the wafer 60 frequently. .

The purge step is a step of removing particles present on the upper surface of the wafer 60 by injecting purge gas into the wafer 60 transferred into the load lock chamber 10 after completion of the second transfer step.

This process is repeated for all the wafers 60 at the slot positions # 1 to #N of the wafer cassette 11 in the load lock chamber 10, and then the wafers 60 are unloaded with SMIF. Particle removal of the epitaxial equipment for semiconductor manufacturing according to an embodiment of the invention is made.

FIG. 7 is a chart showing changes in defect densities such as particles and crystals before and after the N2 purge (FIG. 7A) and after the implementation (FIG. 7B).

The defect density was 15 on average before the N2 purge, but the density was significantly reduced after the N2 purge to be less than 5.

It is apparent to those skilled in the art that the present invention is not limited to the above embodiments and can be practiced in various ways within the scope not departing from the technical gist of the present invention. will be.

As described above, according to the apparatus and method for removing particles using an N2 purge nozzle according to the present invention, by installing an N2 purge nozzle in a load lock chamber, particle generation of epitaxial equipment for handling wafers using a wand is prevented. It can be reduced, thereby stabilizing the process and improving the production yield.

Claims (3)

An epitaxial device for forming an identical layer having the same lattice structure on a wafer for semiconductor manufacturing, comprising: a load lock chamber on which a wafer cassette is placed; A wafer handling chamber connected to a side of the load lock chamber; A process chamber connected with the other side of the wafer handling chamber; A wafer transfer arm installed at an inner center of the wafer handling chamber; A wand connected to one end of the wafer transfer arm; N2 purge nozzle installed in the upper end of the load lock chamber; and a circular plate located on the lower end of the N2 purge nozzle; Particle removal apparatus using the N2 purge nozzle of the epitaxial equipment, characterized in that it comprises a. The apparatus of claim 1, wherein the circular plate is formed with radial injection holes at regular intervals centering directly under the nozzle. In the epitaxial equipment for forming the same layer having the same lattice structure on the wafer for semiconductor manufacturing, the loading step of placing the wafer cassette in the load lock chamber, the first transfer step of conveying the wafer contained in the wafer cassette to the process chamber A process step in which the process is performed in the process chamber, a second transfer step of transferring the wafer to the load lock chamber after the process step, and a purge step in which particles are removed by an N2 purge nozzle in the load lock chamber. Particle removal method using the N2 purge nozzle of the epitaxial equipment characterized in that.

Images