JP2024002229A - Substrate treatment method and substrate treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate treatment method and a substrate treatment apparatus capable of eliminating static of a foreign object in a treatment chamber.

SOLUTION: A substrate treatment method includes the steps of: generating a plasma for eliminating static of a foreign object positioned in a first sputtering room 12A in a transportation room 11 included in a static elimination route outside the first sputtering room 12A; and increasing a pressure inside the first sputtering room 12A to a pressure inside the static elimination route or more such that a charged particle contained in the plasma can reach the inside of the first sputtering room 12A and eliminating static of the foreign object in the first sputtering room 12A by the charged particle reaching the inside of the first sputtering room 12A.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a substrate processing method and a substrate processing apparatus.

An example of a semiconductor device manufacturing apparatus includes a processing chamber and an airlock chamber connected to the processing chamber. The airlock chamber is equipped with a static eliminator and an electrode plate. In a semiconductor device manufacturing apparatus, first, a static eliminator is operated in an airlock chamber before a substrate to be processed is carried in and before the pressure is reduced. As a result, foreign matter adhering to the inner wall of the airlock chamber is neutralized. Next, by reducing the pressure in the airlock chamber, the neutralized foreign matter is exhausted to the outside of the airlock chamber. After the substrate to be processed is carried into the airlock chamber, which has been pressurized to atmospheric pressure, a voltage corresponding to the amount of charge on the substrate is applied to the electrode plate, thereby removing foreign matter attached to the substrate from the electrode plate. move toward In this way, in the semiconductor device manufacturing apparatus, foreign matter attached to the inner wall of the airlock chamber and foreign matter attached to the substrate before processing are removed (see, for example, Patent Document 1).

Japanese Patent Application Publication No. 2002-353086

However, even after the process of removing foreign matter from the substrate is performed in the airlock chamber, some of the foreign matter continues to adhere to the substrate. Foreign objects are also brought into the area. Foreign matter carried into the processing chamber may float within the processing chamber after detaching from the substrate. These foreign substances adhere to substrates carried into the processing chamber, thereby reducing the yield of semiconductor devices.

A substrate processing method for solving the above-mentioned problems includes generating plasma in a static elimination path outside the processing chamber to eliminate static electricity from foreign substances located inside the processing chamber, and charging particles contained in the plasma inside the processing chamber. The method includes increasing the pressure in the processing chamber to be equal to or higher than the pressure in the static elimination path so that the charged particles reach the neutralization path, and neutralizing the foreign matter in the processing chamber by the charged particles that have reached the processing chamber.

A substrate processing apparatus for solving the above problems generates a processing chamber, a static elimination path connected to the processing chamber, and plasma in the static elimination path, and charged particles in the plasma reach the processing chamber. and a static eliminator that adjusts the pressure within the processing chamber to be higher than the pressure within the static eliminator passage.

According to the above-mentioned substrate processing method and substrate processing apparatus, since the pressure inside the processing chamber is higher than the pressure inside the static elimination passage, foreign matter generated in the static elimination passage is suppressed from reaching the processing chamber. By supplying plasma into the processing chamber, it is possible to neutralize foreign matter in the processing chamber.

The substrate processing method may further include discharging the neutralized foreign matter from the processing chamber to the outside of the processing chamber. According to this substrate processing method, since the neutralized foreign matter is discharged from the processing chamber, it is possible to prevent the neutralized foreign matter from floating in the processing chamber again.

In the substrate processing method, eliminating static electricity from the foreign matter includes introducing a first flow rate of gas into the processing chamber, and discharging the foreign matter to the outside of the processing chamber includes introducing a gas having a first flow rate higher than the first flow rate. The method may include introducing two flow rates of gas into the processing chamber. According to this substrate processing method, since the gas at the second flow rate is introduced into the processing chamber, the neutralized foreign matter is easily moved by the flow of fluid within the processing chamber. This makes it easier for foreign matter to be discharged outside the processing chamber.

In the substrate processing method, discharging the foreign matter to the outside of the processing chamber includes introducing gas from a gas inlet and exhausting the inside of the processing chamber from an exhaust port, and the gas inlet and the exhaust port are connected to each other. The pair of walls of the processing chamber may be lined up in opposing directions. According to this substrate processing method, foreign matter in the processing chamber can be moved toward the exhaust port by generating a fluid flow along the direction in which the pair of walls face each other.

1 is a block diagram schematically showing the structure of a cluster tool type sputtering apparatus, which is a substrate processing apparatus according to a first embodiment; FIG. 2 is a block diagram schematically showing the structure of a transfer chamber and a first sputtering chamber included in the sputtering apparatus shown in FIG. 1. FIG. 3 is a flowchart for explaining the substrate processing method of the first embodiment. It is a graph showing the relationship between voltage values and elapsed time at various parts of the substrate. It is a graph showing the relationship between voltage values and elapsed time at various parts of the substrate. FIG. 2 is a block diagram schematically showing the structure of a substrate processing apparatus according to a second embodiment.

[First embodiment]
A first embodiment of a substrate processing method and a substrate processing apparatus will be described with reference to FIGS. 1 to 5.

[Substrate processing equipment]
A substrate processing apparatus will be described with reference to FIGS. 1 and 2. A cluster tool type sputtering apparatus, which is an example of a substrate processing apparatus, will be described below.

As shown in FIG. 1, the cluster tool type sputtering apparatus 10 includes a transfer chamber 11, two sputter chambers 12, a carry-in/out chamber 13, and two substrate processing chambers 14. The sputtering apparatus 10 includes two sputtering chambers 12, a first sputtering chamber 12A and a second sputtering chamber 12B. The transfer chamber 11 is included in the static elimination path. The first sputtering chamber 12A and the second sputtering chamber 12B are examples of processing chambers.

Each processing chamber 12A, 12B, 13, 14 is connected to the transfer chamber 11. A gate valve is located between the transfer chamber 11 and each of the processing chambers 12A, 12B, 13, and 14. When the gate valve opens, the transfer space defined by the transfer chamber 11 and the spaces defined by the processing chambers 12A, 12B, 13, and 14 are communicated with each other. On the other hand, by closing the gate valve, the transfer space of the transfer chamber 11 and each of the processing chambers 12A, 12B, 13, and 14 are separated from each other.

The transfer chamber 11 is equipped with a transfer robot 11R. The transfer robot 11R is configured to be able to transfer substrates between each processing chamber connected to the transfer chamber 11 and the transfer chamber 11. The transfer chamber 11 includes an exhaust section 11E that exhausts the inside of the transfer space defined by the transfer chamber 11. The transfer chamber 11 includes a plasma generation section 11P that generates plasma within the transfer space. For example, the plasma generation unit 11P may be located at the center of the transfer chamber 11 when the transfer chamber 11 is viewed from above.

The carry-in/out chamber 13 is configured to be able to carry unprocessed substrates into the sputtering apparatus 10 from outside the sputtering apparatus 10 and carry out processed substrates from inside the sputtering apparatus 10 to the outside of the sputtering apparatus 10. . The loading/unloading chamber 13 includes an exhaust section 13E. When carrying in substrates, the carry-in/out chamber 13 is separated from the transfer chamber 11, and the carry-in/out entrance of the carry-in/out chamber 13 is opened, thereby opening the carry-in/out chamber 13 to the atmosphere. Next, after the unprocessed substrate is carried in through the carry-in/out entrance, the carry-in/out entrance is closed. Subsequently, the inside of the loading/unloading chamber 13 is exhausted by the exhaust section 13E, whereby the pressure inside the loading/unloading chamber 13 is reduced to the same level as that of the transfer chamber 11. On the other hand, when carrying out the substrate, after the processed substrate is carried from the transfer chamber 11 to the carry-in/out chamber 13, the gate valve located between the carry-in/out chamber 13 and the transfer chamber 11 is closed. Next, after the pressure inside the carry-in/out chamber 13 is increased to atmospheric pressure, the carry-in/out entrance of the carry-in/out chamber 13 is opened. Then, the processed substrate is carried out of the sputtering apparatus 10 from the carry-in/out port.

Each sputtering chamber 12A, 12B is equipped with a cathode 20. Each sputtering chamber 12A, 12B is configured to be able to form a thin film on the surface of a substrate by sputtering using a cathode 20. Each sputtering chamber 12A, 12B is equipped with an exhaust section 12AE, 12BE that exhausts the inside of the processing space defined by the sputtering chamber 12A, 12B.

Each substrate processing chamber 14 is configured to be able to perform predetermined processing on a substrate. The processing performed in the substrate processing chamber 14 may be a pretreatment performed on the substrate before film formation in the sputter chambers 12A, 12B, or may be performed after film formation in the sputter chambers 12A, 12B. It may also be a post-process performed on the substrate. The pre-treatment and post-treatment may be, for example, heating treatment or cooling treatment. Each substrate processing chamber 14 includes an exhaust section 14E that exhausts the inside of the processing space defined by the substrate processing chamber 14. Note that each substrate processing chamber 14 is also an example of a processing chamber.

With reference to FIG. 2, the transfer chamber 11 and the first sputtering chamber 12A will be described in more detail. Note that in FIG. 2, for convenience of illustration, the distance between the plasma generation section 11P and the first sputtering chamber 12A is shorter than the distance between the plasma generation section 11P and the first sputtering chamber 12A in FIG.

As shown in FIG. 2, the transfer chamber 11 defines a transfer space 11S in which the substrate Sb is transferred. The first sputtering chamber 12A defines a first processing space 12AS configured to communicate with the transport space 11S.

A first sputtering chamber 12A is connected to the transfer chamber 11 through a communication portion 10P. The communication portion 10P is connected to the transfer space 11S of the transfer chamber 11 and the first processing space 12AS of the first sputtering chamber 12A. A gate valve 10G is located in the communication portion 10P. By opening the gate valve 10G, the first processing space 12AS is communicated with the transfer space 11S via the communication portion 10P. On the other hand, by closing the gate valve 10G, the first processing space 12AS is separated from the transfer space 11S. The communication portion 10P is included in the static elimination path together with the transfer chamber 11.

The transfer chamber 11 includes a vacuum chamber 11C that defines a transfer space 11S. The transfer chamber 11 includes the plasma generation section 11P as described above. The plasma generation unit 11P generates plasma within the transfer space 11S. The plasma generation unit 11P is, for example, a microwave plasma source.

The transfer chamber 11 further includes a gas introduction section 11A. The gas introduction part 11A is a gas introduction port that the vacuum chamber 11C has. A gas cylinder located outside the sputtering apparatus 10 is connected to the gas introduction section 11A via a mass flow controller. The gas introduction section 11A introduces a predetermined flow rate of gas into the vacuum chamber 11C. The gas introduced by the gas introduction section 11A is an inert gas. The inert gas may be, for example, a noble gas. The noble gas may be, for example, argon gas or helium gas.

The pressure inside the transfer space 11S is adjusted to a predetermined pressure by the exhaust from the above-mentioned exhaust section 11E (see FIG. 1) and the gas introduced from the gas introduction section 11A. The pressure within the transfer space 11S may be, for example, 1×10 ⁻³ Pa or more and 1×10 ⁻¹ Pa or less.

The first sputtering chamber 12A includes a vacuum chamber 12AC that defines a first processing space 12AS. The first sputtering chamber 12A includes the cathode 20, as described above. Cathode 20 includes a target 21 and a backing plate 22. The target 21 is formed of, for example, a metal, a metal compound, or a mixture of a metal and a metal compound. The target 21 has a sputtered surface that is sputtered during film formation on the substrate Sb. The backing plate 22 is joined to the target 21. The backing plate 22 is electrically conductive. The cathode 20 is attached to one surface of the side wall portion that defines the first processing space 12AS. At least the sputtered surface of the target 21 of the cathode 20 is exposed to the first processing space 12AS.

A target power source 23 is connected to the backing plate 22 . When the target power supply 23 applies a voltage to the backing plate 22, a voltage is applied to the target 21 connected to the backing plate 22. The target power supply 23 may be, for example, a DC power supply or an AC power supply.

The first sputtering chamber 12A includes a support section 31 and a suction section 32. The support portion 31 includes a support surface 31F that supports the substrate Sb. The support surface 31F is made of a material different from the material that forms the surface of the substrate Sb that contacts the support surface 31F. For example, the support surface 31F may be made of aluminum oxide, and the substrate Sb may be a glass substrate. For example, the support portion 31 has a flat plate shape, and the support surface 31F is one plane that the support portion 31 has.

The suction part 32 is located within the support part 31. The adsorption section 32 electrostatically adsorbs the Sb substrate located on the support surface 31F to the support surface 31F. The suction unit 32 is an electrostatic chuck that suctions the substrate Sb using electrostatic force.

The first sputtering chamber 12A includes a position changing section 33. The position changing section 33 is configured to be able to change the position of the support section 31 with respect to the cathode 20. The position changing section 33 changes the position of the support section 31 between the first position and the second position. When the support portion 31 is located at the first position, the support surface 31F is substantially orthogonal to the cathode 20. That is, when the support portion 31 is located at the first position, the support surface 31F is located substantially along the horizontal direction. On the other hand, when the support portion 31 is located at the second position, the support surface 31F is substantially parallel to the cathode 20. That is, when the support portion 31 is located at the second position, the support surface 31F is located substantially along the vertical direction.

The first sputtering chamber 12A further includes a first static elimination gas introduction section 34A and a second static elimination gas introduction section 34B. Each static elimination gas introduction part 34A, 34B is a gas introduction port that the vacuum chamber 12AC has. A gas cylinder located outside the sputtering apparatus 10 is connected to the static elimination gas introduction parts 34A and 34B via a mass flow controller. Note that one mass flow controller may be connected to the two static elimination gas introduction sections 34A and 34B, or one common mass flow controller may be connected to the two static elimination gas introduction sections 34A and 34B. Good too.

The static elimination gas introduction parts 34A and 34B introduce a predetermined flow rate of static elimination gas into the vacuum chamber 12AC. The static eliminating gas introduced by the static eliminating gas introduction parts 34A and 34B is an inert gas. The inert gas may be, for example, a noble gas. The noble gas may be, for example, argon gas or helium gas. It is preferable that the static elimination gas introduced by the static elimination gas introduction parts 34A and 34B is the same gas as the gas introduced by the gas introduction part 11A of the transfer chamber 11.

In the vacuum chamber 12AC, the position of the first static elimination gas introduction part 34A is the first position, and the position of the second static elimination gas introduction part 34B is the second position. The support portion 31 is configured such that the first position and the second position can sandwich the support surface 31F when viewed from a viewpoint facing the plane on which the support surface 31F extends. That is, when the support part 31 is located at the first position and thereby the support surface 31F is located along the substantially horizontal direction, when viewed from a viewpoint facing the support surface 31F, the first static elimination gas introduction part 34A and The support surface 31F is sandwiched between the second static elimination gas introduction section 34B and the support surface 31F.

The vacuum chamber 12AC includes a pair of walls facing each other in the vertical direction. The pair of walls includes an upper wall and a lower wall. The first static elimination gas introduction section 34A and the second static elimination gas introduction section 34B are located on the lower wall. Each static elimination gas introduction part 34A, 34B introduces gas into the first processing space 12AS along the vertical direction from below to above.

The vacuum chamber 12AC further includes an exhaust port 36 to which the exhaust section 12AE is connected. When the support surface 31F is located along the substantially horizontal direction, the exhaust port 36, the first static elimination gas introduction section 34A, and the second static elimination gas introduction section 34B are , are preferably located on one straight line.

The vacuum chamber 12AC further includes a pair of side walls facing each other. Each side wall portion is a wall portion extending along the vertical direction, and is connected to the above-mentioned upper wall portion and lower wall portion. It is preferable that one of the static elimination gas introduction parts 34A, 34B and the exhaust port 36 are lined up along the direction in which the pair of side wall parts face each other. It is preferable that one of the static elimination gas introduction parts 34A and 34B is located near one side wall, and the exhaust port 36 is located near the other side wall. Note that the first sputtering chamber 12A preferably includes a plurality of gas introduction sections. The plurality of gas introduction portions are preferably located along the side wall portions in a direction perpendicular to the direction in which the pair of side wall portions face each other.

When the static electricity in the first sputtering chamber 12A is eliminated, the inside of the first processing space 12AS is heated to a predetermined level by the exhaust from the exhaust section 12AE and the static elimination gas introduced from the static elimination gas introduction sections 34A and 34B. Adjusted to pressure. The pressure within the first processing space 12AS is greater than or equal to the pressure within the transfer space 11S. The pressure within the first processing space 12AS may be, for example, 1×10 ⁻¹ Pa or more and 1×10 ¹ Pa or less.

The first sputtering chamber 12A further includes a film-forming gas introduction section 35. The film-forming gas introduction part 35 is a gas introduction port that the vacuum chamber 12AC has. The film-forming gas introduction section 35 is connected to a gas cylinder located outside the sputtering apparatus 10 via a mass flow controller. The film-forming gas introducing section 35 introduces a plasma-generating gas into the first processing space 12AS. The plasma generating gas may be, for example, an inert gas or a mixed gas of an inert gas and a reactive gas. The plasma generation gas introduced by the film forming gas introduction section 35 is preferably the same gas as the gas introduced by the static elimination gas introduction sections 34A and 34B.

When the support part 31 is located at the second position and the support surface 31F is located substantially along the vertical direction, the film-forming gas introduction part 35 and the support part 31 are aligned with each other when viewed from a viewpoint facing the horizontal surface. It is preferable to be located between the target 21 and the target 21 . The film-forming gas introduction section 35 is located on the upper wall of the vacuum chamber 12AC. The film-forming gas introduction section 35 introduces gas into the first processing space 12AS along the vertical direction from above to below.

When a film is formed on the substrate Sb, the pressure inside the first processing space 12AS is adjusted to a predetermined pressure by the exhaust from the exhaust part 12AE and the plasma generation gas introduced from the film-forming gas introduction part 35. be done. The pressure within the first processing space 12AS may be, for example, 1×10 ⁻¹ Pa or more and 1×10 ¹ Pa or less. The pressure within the first processing space 12AS during film formation is preferably the same as the pressure within the first processing space 12AS during static elimination within the first sputtering chamber 12A.

[Substrate processing method]
A substrate processing method will be described with reference to FIG.
The substrate processing method of the present disclosure includes generating plasma and eliminating electricity from foreign matter in a processing chamber. By generating plasma, plasma is generated to eliminate static electricity from foreign matter located inside the processing chamber in the static elimination path outside the processing chamber. To eliminate static electricity from foreign particles in the processing chamber, the pressure inside the processing chamber is made higher than the pressure in the static elimination passage so that the charged particles contained in the plasma can reach the processing chamber, and the charged particles that have reached the processing chamber can eliminate the foreign particles in the processing chamber. Eliminate static electricity.

According to the substrate processing method of the present disclosure, since the pressure in the processing chamber is higher than the pressure in the static elimination passage, the plasma generated in the static elimination passage is suppressed while preventing foreign matter in the static elimination passage from reaching the processing chamber. By supplying it into the processing chamber, it is possible to eliminate static electricity from foreign substances in the processing chamber. Hereinafter, the substrate processing method will be described in detail with reference to the drawings.

The substrate processing method includes a substrate carrying-in process (step S11), a film forming process (step S12), a substrate carrying-out process (step S13), and a static elimination process (step S14). Note that the static elimination process of this embodiment also serves as a discharge process. That is, in this embodiment, the static elimination process and the discharge process are performed simultaneously.

Note that before the substrate loading step is performed, the pressure within the transfer space 11S is adjusted to a pressure within a range of, for example, 1×10 ⁻³ Pa or more and 1×10 ⁻¹ Pa or less. On the other hand, the pressure in the first processing space 12AS is adjusted to a pressure within a range of, for example, 1×10 ⁻¹ Pa or more and 1×10 ¹ Pa or less. Note that the pressure within the transfer space 11S is adjusted to a predetermined pressure by introducing gas from the gas introduction section 11A and exhausting from the exhaust section 11E. On the other hand, the pressure in the first processing space 12AS is adjusted to a predetermined pressure by introducing gas from the static elimination gas introduction parts 34A and 34B and exhausting by the exhaust part 12AE.

In the substrate loading step, first, the transport robot 11R transports the unprocessed substrate Sb located in the transport chamber 11 into the first sputtering chamber 12A. At this time, the gate valve 10G located in the communication section 10P connecting the transfer chamber 11 to the first sputtering chamber 12A is open. Next, the transfer robot 11R places the substrate Sb on the support surface 31F of the support section 31 located at the first position. After that, the gate valve 10G is closed. Then, the suction unit 32 suctions the substrate Sb located on the support surface 31F to the support surface 31F.

In the film formation process, first, gas introduction from the static elimination gas introduction parts 34A and 34B is switched to gas introduction from the film formation gas introduction part 35. In addition, it is preferable that the total flow rate of the gas introduced from the static elimination gas introduction parts 34A and 34B and the flow rate of the gas introduced from the film-forming gas introduction part 35 are the same. This suppresses fluctuations in the pressure within the first processing space 12AS before and after switching the gas introduction.

Next, the position changing section 33 changes the position of the support section 31 from the first position to the second position. Then, when the target power supply 23 applies a voltage to the backing plate 22, plasma is generated from the gas located around the target 21. As a result, the surface of the target 21 to be sputtered is sputtered. As a result, a thin film is formed on the substrate Sb by the sputtered particles flying from the surface to be sputtered toward the substrate Sb. When the voltage application to the target 21 continues for a predetermined period of time, the target power supply 23 stops applying the voltage to the backing plate 22. After that, the position changing section 33 changes the position of the support section 31 from the second position to the first position.

In the substrate unloading process, first, the suction unit 32 releases the suction of the substrate Sb from the support surface 31F. Next, gas introduction from the film-forming gas introduction section 35 is switched to gas introduction from the static elimination gas introduction sections 34A and 34B. In addition, it is preferable that the total flow rate of the gas introduced from the static elimination gas introduction parts 34A and 34B and the flow rate of the gas introduced from the film-forming gas introduction part 35 are the same. This suppresses fluctuations in the pressure within the first processing space 12AS before and after switching the gas introduction.

Subsequently, after the gate valve 10G is opened, the transfer robot 11R receives the processed substrate Sb from the support section 31. Then, the transport robot 11R transports the processed substrate Sb from the first sputtering chamber 12A to the transport chamber 11.

In the static elimination process, the plasma generation unit 11P generates plasma from the gas in the transfer space 11S with the gate valve 10G open. The charged particles contained in the plasma collide with particles located within the transport space 11S and the first processing space 12AS, thereby moving from the transport space 11S toward the first processing space 12AS through the communication portion 10P. At this time, since the pressure is higher than the pressure in the transfer space 11S of the first processing space 12AS, movement of foreign matter from the transfer space 11S toward the first processing space 12AS is suppressed. Moving the charged particles from the transport space 11S to the first processing space 12AS and not moving the foreign matter in the transport space 11S to the first processing space 12AS reduces the pressure in each space and the particles under the pressure. This is realized by the difference in mean free path.

As a result, the plasma generated in the transfer space 11S is supplied into the first processing space 12AS, so that charged foreign matter floating in the first processing space 12AS and charged foreign matter adhering to the vacuum chamber 11C, etc. is neutralized by charged particles in the plasma. Thus, in this embodiment, the static eliminator includes the plasma generation section 11P, the gas introduction section 11A, the exhaust section 11E, the static elimination gas introduction sections 34A and 34B, and the exhaust section 12AE. The static eliminator generates plasma within the static eliminator passage, and adjusts the pressure within the first sputter chamber 12A to be higher than the pressure within the static eliminator passage so that charged particles in the plasma reach the first sputter chamber 12A.

In the static elimination process, the static elimination gas introduced into the first processing space 12AS causes the fluid to flow toward the exhaust port 36, so that at least a portion of the neutralized foreign matter moves toward the exhaust port 36 due to the fluid flow. do. As a result, the neutralized foreign matter is discharged from the inside of the first sputtering chamber 12A to the outside of the first sputtering chamber 12A. As described above, according to the substrate processing method of the present embodiment, the neutralized foreign matter is discharged from the first sputtering chamber 12A, so that it is possible to prevent the neutralized foreign matter from floating in the first sputtering chamber 12A again. .

In addition, by arranging the static elimination gas introduction portions 34A, 34B and the exhaust port 36 along the direction in which the pair of side wall portions face each other, a fluid flow is generated in the direction in which the pair of side wall portions face each other. Therefore, it is possible to move foreign matter in the first sputtering chamber 12A toward the exhaust port 36.

Note that when the total flow rate of the gas introduced into the first sputtering chamber 12A when neutralizing foreign matter is the first flow rate, the discharge processing step of discharging the foreign matter to the outside of the first sputtering chamber 12A is performed at the first flow rate. It is preferable to include introducing a second flow rate of gas into the first sputtering chamber 12A. In this case, after the plasma generation unit 11P finishes generating plasma, the total flow rate of the gas introduced into the first sputtering chamber 12A from the static elimination gas introduction units 34A and 34B is changed from the first flow rate to the second flow rate. do it. As a result, the second flow rate of gas is introduced into the first sputtering chamber 12A, so that the neutralized foreign matter can be easily moved by the flow of fluid within the first sputtering chamber 12A. As a result, foreign matter is more likely to be discharged outside the first sputtering chamber 12A.

Further, the second sputtering chamber 12B described above has the same configuration as the first sputtering chamber 12A. That is, the sputtering apparatus 10 further includes a second sputtering chamber 12B connected to the transfer chamber 11 included in the static elimination path. The static eliminator generates plasma in the transfer chamber 11 included in the static eliminator passage, and changes the pressure in the second sputter chamber 12B to the pressure in the static eliminator passage so that charged particles in the plasma reach the second sputter chamber 12B. Adjust as above. The static eliminating section includes the above-described exhaust section 12BE of the second sputtering chamber 12B and a static eliminating gas introduction section provided in the second sputtering chamber 12B.

In this case, it is possible to eliminate static electricity in the first sputtering chamber 12A and in the second sputtering chamber 12B using one static eliminating section. Therefore, the number of parts constituting the sputtering apparatus 10 can be reduced compared to the case where the sputtering apparatus 10 includes a static eliminator for each processing chamber.

Note that the above-described configuration can be realized because the static eliminating unit includes the plasma generating unit 11P as a generating unit that generates charged particles for static elimination. For example, the range to which the plasma generated by the plasma generation unit 11P is supplied is relatively wider than when the static elimination unit eliminates static electricity from the processing chamber by irradiating ultraviolet rays. Therefore, it is possible to eliminate static electricity in a plurality of processing chambers using a static elimination unit that includes only one plasma generation unit. When eliminating static electricity within a processing chamber by irradiating ultraviolet rays, one or more irradiation units that irradiate ultraviolet rays are required for each processing chamber, and each irradiation unit must be located within the processing chamber. be done.

[Test Example 1]
Test Example 1 will be described with reference to FIGS. 4 and 5.
In a cluster tool type sputtering apparatus including a first sputtering chamber and a transfer chamber, a plasma generation section was attached to the center of the transfer chamber when the transfer chamber was viewed from above. Next, a charging plate was attached to the support located in the first sputtering chamber. At this time, one charging plate was attached to each of the four corners of the square-shaped support surface. Then, with the gate valve located between the first sputtering chamber and the transfer chamber open, plasma was generated in the transfer chamber using the plasma generation section. The voltage value of the charging plate was monitored from the time of plasma generation.

FIG. 4 is a graph showing changes over time in the voltage value at the charging plate when the pressure in the first sputtering chamber was adjusted to 1×10 ⁻³ Pa and the pressure in the transfer chamber was adjusted to 1×10 ⁻² Pa. It is. FIG. 5 is a graph showing changes over time in the voltage value at the charging plate when the pressure in the first sputtering chamber was adjusted to 0.3 Pa and the pressure in the transfer chamber was adjusted to 1×10 ⁻¹ Pa. Note that among the four charging plates, the distance between the charging plate C and the plasma generation section is the smallest, and the distance between the charging plate D and the plasma generation section is the second smallest. Furthermore, among the four charging plates, the distance between charging plate B and the plasma generation section is the second largest, and the distance between charging plate A and the plasma generation section is the largest.

As shown in FIG. 4, when the pressure in the first sputtering chamber was lower than the pressure in the transfer chamber, it was found that the charging plate was more easily neutralized as the distance from the plasma generation section was smaller. Furthermore, it was found that even with the charging plate closest to the plasma generation part, it took 150 seconds or more for the voltage value of the charging plate to reach -100V. Furthermore, even after 200 seconds have passed from the start of static elimination processing, the voltage value of charging plate A is approximately -600V, the voltage value of charging plate B is approximately -400V, and the voltage value of charging plate D is approximately -200V was confirmed.

As shown in FIG. 5, if the pressure in the first sputtering chamber is higher than the pressure in the transfer chamber, the voltage value will drop to -200V on all charging plates after 200 seconds have passed from the start of the static elimination process. It was accepted that it was below. In addition, when the voltage values of the same charging plate were compared when the pressure inside the first sputtering chamber was lower than the pressure inside the transfer chamber and when the pressure inside the first sputtering chamber was higher than the pressure inside the transfer chamber, the following results were obtained. The following matters were recognized. That is, in any of the charging plates, when the pressure in the first sputtering chamber is higher than the pressure in the transfer chamber, the absolute value of the voltage decreases at a high rate within 100 seconds from the start of the static elimination process, or It was found that the pressure in the first sputtering chamber was about the same as that in the case where the pressure was lower than the pressure in the transfer chamber.

In this way, when the pressure inside the first sputtering chamber is higher than the pressure inside the transporting chamber, the charge in the plasma generated inside the transporting chamber is lower than when the pressure inside the first sputtering chamber is lower than the pressure inside the transporting chamber. It was observed that particles easily reached the first sputtering chamber. Furthermore, it was found that when the pressure inside the first sputtering chamber was higher than the pressure inside the transfer chamber, the amount of charged particles arriving was less likely to vary within the first sputtering chamber.

[Test Example 2]
[Test Example 2-1]
First, using the cluster tool type sputtering apparatus used in Test Example 1, the substrate to be processed was carried from the transfer chamber into the first sputtering chamber, and then the substrate was placed on the support section. Thereafter, the substrate was transported from the first sputtering chamber to the transfer chamber. The substrate was carried out of the sputtering apparatus, and then the number of foreign substances attached to the carried out substrate was counted. This process was performed on three substrates.

Next, using the same sputtering apparatus, before carrying the unprocessed substrate from the transfer chamber into the first sputtering chamber, static elimination treatment was performed. In the static elimination process, the pressure in the first sputtering chamber was adjusted to 0.3 Pa, and the pressure in the transfer chamber was adjusted to 1×10 ⁻¹ Pa. Furthermore, in the static elimination process, argon gas was introduced into both the first sputtering chamber and the transfer chamber. Next, after carrying the substrate to be processed from the transfer chamber into the first sputtering chamber, the substrate was placed on the support section. Thereafter, the substrate was transported from the first sputtering chamber to the transfer chamber. The substrate was carried out of the sputtering apparatus, and then the number of foreign substances attached to the carried out substrate was counted. This process was performed on three substrates.

When static elimination processing is not performed, the average number of foreign particles with a size of 5 μm or more among foreign particles attached to the substrate is 270, and the average value of the number of foreign particles with a size of 20 μm or more is 270. It was recognized that the value was 30.3 pieces. On the other hand, when the static elimination process was performed, the average number of foreign particles with a size of 5 μm or more among the foreign particles attached to the substrate was 197, which was 197 particles with a size of 20 μm or more. The average number of foreign objects was found to be 19.7.

Thus, according to the results of Test Example 2-1, it was recognized that the amount of foreign matter adhering to the substrate could be reduced by performing the static elimination process.

[Test Example 2-2]
In Test Example 2-1, the same process as in Test Example 2-1 was performed except that the substrate was subjected to a film formation process. That is, in Test Example 2-2, first, the substrate before processing was carried into the first sputtering chamber from the transfer chamber, and then the substrate was placed on the support section. Thereafter, a thin film was formed on the substrate by sputtering the target in the first sputtering chamber. Subsequently, the substrate was transported from the first sputtering chamber to the transfer chamber. The substrate was carried out of the sputtering apparatus, and then the number of foreign substances attached to the carried out substrate was counted. This process was performed on three substrates.

Note that the conditions for the film forming process were set as follows.
・Target Aluminum ・Sputtering gas Argon gas ・Pressure in the first sputtering chamber 0.3Pa

Next, using the same sputtering apparatus, before carrying the unprocessed substrate from the transfer chamber into the first sputtering chamber, static elimination treatment was performed. In the static elimination process, the pressure in the first sputtering chamber was adjusted to 0.3 Pa, and the pressure in the transfer chamber was adjusted to 1×10 ⁻¹ Pa. Next, after carrying the substrate to be processed from the transfer chamber into the first sputtering chamber, the substrate was placed on the support section. Thereafter, a thin film was formed on the substrate by sputtering the target in the first sputtering chamber. Subsequently, the substrate was transported from the first sputtering chamber to the transfer chamber. The substrate was carried out of the sputtering apparatus, and then the number of foreign substances attached to the carried out substrate was counted. This process was performed on three substrates.

When static elimination processing is not performed, the average number of foreign particles with a size of 5 μm or more among the foreign particles attached to the substrate is 226, and the average value of the number of foreign particles with a size of 20 μm or more is 226. It was recognized that the value was 13.3. On the other hand, when the static elimination process was performed, the average number of foreign particles with a size of 5 μm or more among the foreign particles attached to the substrate was 162, which was 162 particles with a size of 20 μm or more. It was found that the average number of foreign particles was 5.0.

Thus, according to the results of Test Example 2-2, it was recognized that the amount of foreign matter adhering to the substrate could be reduced by performing the static elimination process.
As explained above, according to the first embodiment of the substrate processing method and substrate processing apparatus, the following effects can be obtained.

(1-1) The pressure in the first sputtering chamber 12A is higher than the pressure in the static elimination path. Therefore, by supplying the plasma generated in the static eliminating path to the first sputtering chamber 12A while suppressing foreign matter in the static eliminating path from reaching the first sputtering chamber 12A, It is possible to eliminate static electricity from foreign objects.

(1-2) Since the neutralized foreign matter is discharged from the first sputtering chamber 12A, it is possible to prevent the neutralized foreign matter from floating in the first sputtering chamber 12A again.
(1-3) When introducing the gas at the second flow rate into the first sputtering chamber 12A, the neutralized foreign matter becomes easier to move due to the flow of fluid within the first sputtering chamber 12A. This makes it easier for foreign matter to be discharged out of the first sputtering chamber 12A.

(1-4) It is possible to move foreign matter in the first sputtering chamber 12A toward the exhaust port 36 by generating a fluid flow along the direction in which the pair of wall portions face each other.

[Second embodiment]
A second embodiment of a substrate processing method and a substrate processing apparatus will be described with reference to FIG.
[Substrate processing equipment]
The substrate processing apparatus will be explained with reference to FIG. A sputtering apparatus that is an example of a substrate processing apparatus will be described below.

As shown in FIG. 6, the sputtering apparatus 40 includes a sputtering chamber 41 and a static elimination path 42. The sputtering chamber 41 includes a vacuum chamber 41C that defines a space in which sputtering is performed on the substrate Sb. The static elimination passage 42 is connected to the static elimination port 43 that the vacuum chamber 41C has. The static elimination path 42 is located outside the space defined by the vacuum chamber 41C.

A plasma generation section 44 is attached to the static elimination path 42 . The plasma generation unit 44 is, for example, a microwave plasma source. The plasma generation section 44 is configured to be able to generate plasma within the static elimination path 42. The static elimination passage 42 includes a static elimination valve 42A. By opening the static elimination valve 42A, the static elimination passage 42 is connected to the vacuum chamber 41C. On the other hand, by closing the static elimination valve 42A, the static elimination passage 42 is separated from the vacuum chamber 41C.

The sputtering device 40 includes an exhaust section 45. The exhaust section 45 is connected to an exhaust port 46 included in the vacuum chamber 41C. The exhaust section 45 includes an exhaust valve 45A, a first exhaust pump 45B, a second exhaust pump 45C, and an exhaust passage 45D. In the direction in which fluid is exhausted by the exhaust section 45, the exhaust valve 45A is located at the most downstream position, and the second exhaust pump 45C is located at the most upstream position. The second exhaust pump 45C is connected to the first exhaust pump 45B by an exhaust passage 45D. A static elimination path 42 is connected to the exhaust path 45D. The exhaust valve 45A may be a butterfly valve, for example. The first exhaust pump 45B may be, for example, a turbo molecular pump. The second exhaust pump 45C may be, for example, a dry pump.

A support portion 47 that supports the substrate Sb is located within the vacuum chamber 41C. A cathode 50 is attached to the vacuum chamber 41C at a position facing the support portion 47. Cathode 50 includes a target 51 and a backing plate 52. The target 51 is formed of, for example, a metal, a metal compound, or a mixture of a metal and a metal compound. The target 51 has a sputtered surface that is sputtered during film formation on the substrate Sb. The backing plate 52 is joined to the target 51. The backing plate 52 has electrical conductivity. At least the sputtered surface of the target 51 of the cathode 50 is exposed to the space defined by the vacuum chamber 41C.

A target power source 53 is connected to the backing plate 52. When the target power supply 53 applies a voltage to the backing plate 52, a voltage is applied to the target 51 connected to the backing plate 52. The target power supply 53 may be, for example, a DC power supply or an AC power supply.

The vacuum chamber 41C has a gas inlet 48. A gas cylinder located outside the sputtering apparatus 40 is connected to the gas inlet 48 via a mass flow controller. The gas introduction port 48 introduces a predetermined flow rate of gas into the vacuum chamber 41C. The gas introduced through the gas inlet 48 may be, for example, an inert gas. The inert gas may be, for example, a noble gas. The noble gas may be, for example, argon gas or helium gas. Note that the gas introduced from the gas introduction port 48 may contain a reactive gas. The reactive gas may be, for example, oxygen gas.

The gas introduced from the gas inlet 48 may be switched between the first gas and the second gas. For example, while the first gas may be used when sputtering the target 51 to thereby form a thin film on the substrate Sb, the second gas may be used when removing static from foreign matter in the vacuum chamber 41C. In this case, for example, the first gas may be a mixed gas of an inert gas and a reactive gas, and the second gas may be an inert gas.

The vacuum chamber 41C includes a pair of side walls facing each other. Each side wall portion is a wall portion extending along the vertical direction, and is connected to the upper wall portion and the lower wall portion. The gas introduction port 48 and the static elimination port 43 are lined up along the direction in which the pair of side wall portions face each other. It is preferable that one of the gas inlet ports 48 be located near one side wall, and the static elimination port 43 be located in the other side wall. Note that the sputtering chamber 41 is preferably provided with a plurality of gas introduction ports. The plurality of gas introduction ports are preferably located along the side wall portions in a direction perpendicular to the direction in which the side wall portions face each other.

The pressure in the space defined by the vacuum chamber 41C is adjusted to the first pressure by the gas introduced from the gas inlet 48 and the exhaust from the exhaust section 45 through the exhaust port 46. The first pressure is, for example, a pressure within a range of 1×10 ⁻¹ Pa or more and 1×10 ¹ Pa or less. On the other hand, the pressure in the exhaust passage 45D is adjusted by the exhaust section 45 to a second pressure that is lower than the first pressure. The second pressure is, for example, a pressure within a range of 1×10 ⁻³ Pa or more and 1×10 ⁻¹ Pa or less.

[Substrate processing method]
Similar to the substrate processing method of the first embodiment described above, the substrate processing method of this embodiment includes a substrate carrying-in step, a film-forming step, a substrate carrying-out step, and a static elimination processing step. Note that the static elimination process of this embodiment also serves as a discharge process, similar to the static elimination process of the first embodiment. Note that before the carrying-in/out process is performed, the exhaust section 45 is driven with the exhaust valve 45A opened and the static elimination valve 42A closed. When the exhaust section 45 is driven, the second exhaust pump 45C is first driven, and then, when the pressure inside the vacuum chamber 41C is reduced to a predetermined pressure, the first exhaust pump 45B is driven. As a result, the pressure inside the vacuum chamber 41C is further reduced.

In the substrate loading step, a loading/unloading port of the vacuum chamber 41C (not shown) is opened. Next, the substrate Sb is loaded into the vacuum chamber 41C from the loading/unloading port, and the loaded substrate Sb is placed on the support section 47. In addition, since the loading/unloading entrance of the vacuum chamber 41C is connected to a loading/unloading chamber configured to be able to reduce the pressure, the loading/unloading of the substrate Sb before processing into the vacuum chamber 41C and the loading/unloading of the substrate Sb after processing into the vacuum chamber 41C The inside of 41C is not exposed to the atmosphere.

In the film forming process, first, a predetermined flow rate of gas is introduced from the gas introduction port 48. Thereby, the pressure within the vacuum chamber 41C is adjusted to the first pressure. Next, the target power supply 53 applies voltage to the target 51 via the backing plate 52, thereby generating plasma around the target 51. As a result, the sputtered surface of the target 51 is sputtered, and sputtered particles are emitted from the sputtered surface. As a result, the sputtered particles reach the substrate Sb, thereby forming a thin film on the substrate Sb. After gas introduction continues for a predetermined period of time, gas introduction and voltage application are stopped. As a result, a thin film having a predetermined thickness is formed on the substrate Sb.

In the substrate carrying-out process, the carrying-out port of the vacuum chamber 41C described above is opened. Next, the substrate Sb is carried out of the vacuum chamber 41C from the carry-in/out port.
In the static elimination process, first, the exhaust valve 45A is closed, and the static elimination valve 42A is opened. Next, gas is introduced into the vacuum chamber 41C from the gas inlet 48, thereby adjusting the pressure within the vacuum chamber 41C to the first pressure. At this time, the pressure in the exhaust passage 45D is adjusted to a second pressure that is lower than the first pressure. Therefore, the pressure in the neutralization passage 42 decreases along the direction from the vacuum chamber 41C to the exhaust passage 45D.

Next, the plasma generation unit 44 generates plasma in the static elimination path 42 . At this time, a part of the gas introduced into the vacuum chamber 41C through the static elimination port 43 is introduced into the static elimination passage 42, so that plasma is generated from the gas. Charged particles contained in the plasma collide with particles located within the static elimination passage 42 and within the vacuum chamber 41C, thereby moving from the static elimination passage 42 toward the vacuum chamber 41C. At this time, since the pressure within the vacuum chamber 41C is higher than the pressure within the static elimination passage 42, movement of foreign matter from the static elimination passage 42 toward the vacuum chamber 41C is suppressed. Moving the charged particles from the static elimination passage 42 to the vacuum chamber 41C and not moving the foreign matter in the static elimination passage 42 to the vacuum chamber 41C is due to the pressure in each space and the mean free path of the particles under the pressure. Realized by difference.

As a result, the plasma generated in the static elimination passage 42 is supplied to the vacuum chamber 41C, so that charged foreign matter floating in the vacuum chamber 41C and charged foreign matter adhering to the vacuum chamber 41C are removed from the plasma. Static electricity is removed by charged particles. As described above, in this embodiment, the static elimination section includes the plasma generation section 44, the exhaust section 45, and the gas introduction port 48.

Furthermore, in the static elimination process, the gas introduced into the vacuum chamber 41C causes fluid to flow toward the static elimination port 43, so that the foreign matter from which static electricity has been eliminated moves toward the static elimination port 43 due to the flow of the fluid. As a result, the neutralized foreign matter is discharged from the vacuum chamber 41C to the outside of the vacuum chamber 41C.

In this embodiment, the path through which the charged particles generated by the plasma generation unit 44 move toward the vacuum chamber 41C is the same path through which the neutralized foreign matter is discharged. That is, both the charged particles and the foreign matter pass through the same static elimination path 42. Therefore, since there is a possibility that the foreign matter collides with the charged particles even when moving toward the static elimination path 42, it is possible to prevent the foreign matter from being insufficiently neutralized.

Note that when the flow rate of the gas introduced into the sputtering chamber 41 when removing static electricity from foreign matter is the first flow rate, the discharge treatment step of discharging the foreign matter to the outside of the sputtering chamber 41 is performed at a second flow rate larger than the first flow rate. Preferably, the method includes introducing a flow rate of gas into the sputtering chamber 41 . In this case, after the plasma generation unit 44 finishes generating plasma, the total flow rate of the gas introduced into the vacuum chamber 41C from the gas introduction port 48 may be changed from the first flow rate to the second flow rate. As a result, the second flow rate of gas is introduced into the vacuum chamber 41C, so that the neutralized foreign matter can be easily moved by the flow of fluid within the vacuum chamber 41C. As a result, foreign matter is more likely to be discharged outside the vacuum chamber 41C.

Furthermore, by arranging the gas inlet 48 and the static elimination port 43 along the direction in which the pair of side walls face each other, a fluid flow is generated in the direction in which the pair of side walls face each other. can be moved toward the static elimination port 43.

As explained above, according to the second embodiment of the substrate processing method and substrate processing apparatus, in addition to the above-mentioned (1-1) to (1-4), the following effects can be obtained.
(2-1) Since the path through which the charged particles move and the path through which foreign matter is discharged are the same, there is a possibility that the foreign matter will collide with the charged particles when it moves toward the static elimination path 42. This prevents insufficient charge removal from foreign matter.

[Example of change]
In addition, each embodiment mentioned above can be changed and implemented as follows.
[Static electricity removal process]
- In each embodiment, in the substrate processing method, when repeating film formation on the substrate Sb, static elimination processing may be performed before carrying in the first substrate Sb.

- In each embodiment, in the static elimination process, while the static electricity of the foreign matter is eliminated, it is not necessary to discharge the foreign matter. For example, by adjusting at least one of the exhaust flow rate of the exhaust section and the flow rate of the gas introduced into the processing chamber, it is possible to suppress the discharge of foreign matter that occurs when static electricity is removed from the foreign matter.

[Substrate processing method]
- In the first embodiment, when performing the static elimination process, exhausting the transport space 11S by the exhaust section 11E may be omitted. Even in this case, if the conductance of the communication portion 10P is sufficiently high, by opening the gate valve 10G, both the first processing space 12AS and the transfer space 11S are It is possible to exhaust air through section 12AE. By adjusting the flow rate of the gas introduced from the gas introduction section 11A and the flow rate of the gas introduced from the static elimination gas introduction sections 34A and 34B, the pressure in the first processing space 12AS is changed to the pressure in the transfer space 11S. It is possible to adjust the size above.

[Sputtering equipment]
- In the first embodiment, the sputtering apparatus 10 may include only the transfer chamber 11 and the first sputtering chamber 12A. Even in this case, it is possible to obtain an effect similar to (1-1) above.

[Substrate processing equipment]
- In each embodiment, the substrate processing apparatus is not limited to a sputtering apparatus, and may be an apparatus that forms a thin film on the substrate Sb by, for example, another method. For example, the substrate processing apparatus may be a CVD apparatus, a vacuum evaporation apparatus, or the like. Further, in each embodiment, the substrate processing apparatus is not limited to an apparatus that performs film formation on the substrate Sb, but may be an apparatus that performs other processing on the substrate Sb. For example, the substrate processing apparatus may be, for example, an etching apparatus. Any device may be used as long as it includes a processing chamber and a static elimination path located outside the processing chamber, and is configured to be able to generate plasma in the static elimination path.

10, 40... Sputtering device 11... Transfer chamber 11P, 44... Plasma generation section 12, 41... Sputtering chamber 12A... First sputtering chamber 12B... Second sputtering chamber 42... Static elimination passage

Claims (5)

generating plasma for neutralizing foreign matter located in the processing chamber in a static elimination path outside the processing chamber; and
The pressure in the processing chamber is made equal to or higher than the pressure in the static elimination path so that charged particles contained in the plasma reach the processing chamber, and the foreign matter in the processing chamber is neutralized by the charged particles that have reached the processing chamber. A substrate processing method, including: The substrate processing method according to claim 1, further comprising discharging the foreign matter from which static electricity has been removed from inside the processing chamber to outside the processing chamber. Eliminating static from the foreign matter includes introducing a first flow rate of gas into the processing chamber,
3. The substrate processing method according to claim 2, wherein discharging the foreign matter to the outside of the processing chamber includes introducing gas into the processing chamber at a second flow rate that is larger than the first flow rate. Discharging the foreign matter to the outside of the processing chamber includes introducing gas from a gas inlet and exhausting the inside of the processing chamber from an exhaust port,
The substrate processing method according to claim 2 , wherein the gas inlet and the exhaust port are arranged along a direction in which a pair of walls of the processing chamber face each other. a processing room;
a static elimination path connected to the processing chamber;
a static eliminator that generates plasma in the static elimination path and adjusts the pressure within the processing chamber to be higher than the pressure within the static elimination path so that charged particles in the plasma reach the processing chamber. .

Images