KR100760019B1 - Substrate processing method for increased substrate throughput - Google Patents

Abstract

A substrate processing method for increasing the substrate throughput is disclosed. The substrate processing method of the present invention quickly seats the substrate loaded into the process chamber on the heating chuck and, in addition, lowers the process chamber to a very low basic air pressure to prevent deformation of the substrate by thermal shock. A certain amount of process gas is injected into the process chamber to increase the pressure in the process chamber so that the substrate is heated quickly and uniformly. According to the substrate processing method of the present invention, by heating the substrate uniformly, it is possible to prevent the substrate from being deformed, thereby increasing the yield while increasing the yield of the substrate while improving the yield.

Photoresist, Ashing, Stripping, Plasma

Description

Substrate processing method to increase substrate throughput {SUBSTRATE PROCESSING METHOD FOR INCREASED SUBSTRATE THROUGHPUT}

In order to more fully understand the drawings used in the detailed description of the invention, a brief description of each drawing is provided.

1 and 2 schematically show a substrate processing system employing the substrate processing method of the present invention.

3 is a flow chart sequentially showing a substrate processing method according to the first embodiment of the present invention.

4 is a schematic view of a substrate processing system employing a substrate processing method according to a second embodiment of the present invention.

5 is a perspective view of the plasma reactor and process chamber of FIG. 4.

6 is a view showing a cross section of the plasma reactor of FIG. And

Fig. 7 is a flowchart showing the substrate processing procedure in order according to the second embodiment of the present invention.

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

10: index 12: cassette

20, 60: transfer chamber 21, 61: transfer robot

30: process chamber 40: plasma reactor

50: load lock chamber

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing method for semiconductor manufacturing, and more particularly, to a substrate heating method for improving substrate throughput and yield.

In order to increase productivity in semiconductor manufacturing processes for manufacturing integrated circuits or liquid crystal displays, a technique for increasing substrate throughput while maintaining high yield is required. High productivity has a very close influence on the price competitiveness of the final product, and technical development efforts are being made to increase it.

BACKGROUND OF THE INVENTION Processes for removing photoresist, called stripping or ashing, are one of the very frequent manufacturing processes in semiconductor manufacturing processes. In the process for removing the photoresist, the substrate is heated to a predetermined temperature or more, and then the process is performed while the substrate is heated. For example, the wafer may be placed on a hot heating chuck to heat the substrate and maintain a constant temperature during the process.

When the substrate is rapidly heated by a high temperature heating chuck, a problem occurs that the substrate is warped, because the substrate is not uniformly heated. Deformation of the substrate has a very bad effect on the elements configured in the substrate, and the deformed substrate causes many other problems in subsequent processes. In order to prevent deformation of the substrate, the substrate may be gradually heated. However, in this case, the substrate productivity is drastically reduced, which is not preferable. Therefore, there is a demand for a method capable of preventing the deformation of the substrate while rapidly heating the substrate.

As a method of heating the substrate while preventing the deformation of the substrate, a method of preheating is used before the substrate is placed on a hot heating chuck. Alternatively, a method of preheating the substrate while keeping the substrate in the loading position for a predetermined time without lowering the lift pin immediately after loading the substrate is used. However, these methods can prevent the substrate from heating rapidly, but there is a problem in that it is difficult to increase the substrate throughput more than a predetermined procedure.

The problem of substrate deformation due to rapid heating of the substrate has been pointed out as the same problem not only in the process for removing the photoresist but also in the semiconductor manufacturing process requiring other substrate heating. Therefore, there is a demand for an effective substrate heating method capable of preventing substrate deformation while rapidly heating the substrate in a semiconductor manufacturing process.

Accordingly, an object of the present invention is to provide a substrate processing method capable of rapidly heating while preventing substrate deformation to increase substrate throughput while increasing process yield.

According to another aspect of the present invention, there is provided a method of processing a substrate, the method including: loading a substrate into a process chamber at a pressure of the process chamber being loaded / unloaded; Changing the air pressure in the process chamber to a base air pressure lower than the substrate processing air pressure; Changing the air pressure of the process chamber to a heating pressure higher than the substrate processing pressure, and moving the substrate from the loading / unloading position to the substrate processing position; Heating the substrate to a process temperature at a heated atmosphere and at a substrate processing location; And changing the atmospheric pressure of the process chamber to the substrate processing pressure and proceeding the substrate processing process.

In this embodiment, the loading / unloading pressure is a substrate processing pressure.

In this embodiment, the loading / unloading pressure is atmospheric pressure.

In this embodiment, the basic barometric pressure is 1 Torr or less. Preferably the basic barometric pressure is 500 mmTorr or less.

In this embodiment, the heating air pressure is 1 Torr or more. Preferably the heating air pressure is at least 10 Torr.

In this embodiment, the change to the heating atmospheric pressure is changed by inputting the process gas into the process chamber.

In this embodiment, in the step of moving to the substrate processing position, the substrate is moved to a heated heating chuck.

In this embodiment, the substrate treatment is a plasma treatment.

According to another feature of the invention, the pressure of the process chamber is a step of loading the substrate into the process chamber at loading / unloading pressure; Changing the atmospheric pressure of the process chamber to a preliminary atmospheric pressure and moving the substrate from the loading / unloading position to the substrate processing position; Operating a plasma reactor of the process chamber at a preliminary atmospheric pressure to generate a plasma; Heating the substrate to a process temperature by the generated plasma; And changing the atmospheric pressure of the process chamber to the substrate processing pressure and proceeding the substrate processing process.

In this embodiment, the loading / unloading pressure is a substrate processing pressure.

In this embodiment, the loading / unloading pressure is atmospheric pressure.

In this embodiment, the preliminary air pressure is 10 Torr or less. Preferably the preliminary air pressure is 500 mmTorr or less.

In this embodiment, in the step of moving to the substrate processing position, the substrate is moved to a heated heating chuck.

In this embodiment, the substrate treatment is a plasma treatment.

In this embodiment, the plasma reactor comprises: a hollow discharge tube head disposed above the process chamber; A plurality of hollow discharge tube bridges connected between the plurality of holes opened in the upper portion of the process chamber and the plurality of holes formed in the lower portion of the discharge tube head; A ferrite core mounted to the plurality of hollow discharge tube bridges; And an induction coil wound around the ferrite core and connected to the power supply.

DETAILED DESCRIPTION In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the embodiments of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings. In understanding the drawings, it should be noted that like parts are intended to be represented by the same reference numerals as much as possible. And detailed description of known functions and configurations that are determined to unnecessarily obscure the subject matter of the present invention is omitted.

Example 1

Hereinafter, with reference to the accompanying drawings illustrating a preferred embodiment of the present invention, a substrate processing method for increasing the substrate throughput of the present invention will be described in detail.

1 and 2 schematically show a substrate processing system employing the substrate processing method of the present invention.

Referring to the drawings, there are two types of substrate processing systems for removing photoresist. One is a system in which the substrate W is transferred to the process chamber 30 at atmospheric pressure, as shown in FIG. 1. The other is a system in which the substrate W is transferred from the vacuum load lock chamber 50 to the process chamber 30, as shown in FIG. 2. The substrate processing method of the present invention can be employed in both systems.

Referring to FIG. 1, one system for removing photoresist includes a transfer chamber 20 having an atmospheric pressure environment and an atmospheric transfer robot 21 installed therein. Atmospheric pressure transfer robot 21 transfers the substrate between the cassette 12 placed in the index 10 and the process chamber 30.

A substrate inlet and outlet 22 is provided between the transfer chamber 20 and the process chamber 30, and the substrate inlet and outlet 22 is opened and closed by a gate valve (not shown). The process chamber 30 is placed in an atmospheric pressure environment during the loading / unloading of the substrate, and is changed to a vacuum environment in the substrate processing process. The exhaust and atmospheric pressure control of the process chamber 30 is controlled by a vacuum pump (not shown). In addition, a plasma reactor 40 for processing the substrate of the process chamber 30 is mounted on the process chamber 30.

Referring to FIG. 2, another system for removing photoresist includes a first transfer chamber 20 having an atmospheric pressure environment and an atmospheric transfer robot 21 provided therein. The atmospheric pressure transfer robot 21 transfers the substrate W between the cassette 12 placed in the index 10 and the load lock chamber 50.

A first substrate entrance 22 is provided between the transfer chamber 20 and the load lock chamber 50 to access the substrate, and the substrate entrance 22 is opened and closed by a gate valve (not shown). The load lock chamber 50 is provided with an accommodating part 51 in which the substrate W is accommodated. Behind the load lock chamber 50 is a second transfer chamber 60, in which a vacuum transfer robot 61 operating in a vacuum environment is installed, is connected, and a process chamber 30 is connected thereto. The vacuum transfer robot 61 transfers the substrate W between the load lock chamber 50 and the process chamber 30 in a vacuum state.

A second substrate entrance 61 is provided between the load lock chamber 50 and the second transfer chamber 60 for entering and exiting the substrate W, and is opened and closed by another gate valve (not shown). A third substrate entrance 62 is provided between the second transfer chamber 60 and the process chamber 30, and is opened and closed by another gate valve (not shown). The exhaust and atmospheric pressure control of the load lock chamber 50, the second transfer chamber 60, and the process chamber 30 is controlled by one or more vacuum pumps (not shown). In addition, a plasma reactor 40 for processing the substrate of the process chamber 30 is mounted on the process chamber 30.

The two systems for removing the above photoresist remove the photoresist film applied to the substrate after the etching process or the deposition process. In addition to the systems described above, there may be other types of photoresist removal systems, but those skilled in the art will be well aware of them without providing examples.

An ashing process in which the substrate W is loaded into the process chamber 30 and then heated to a process temperature of about 250 ° C. to remove the photoresist film applied to the substrate W, and then the photoresist film is removed by plasma treatment. This is going on. In the present invention, a method for heating the substrate W to a process temperature provides a method for heating the substrate quickly and so as not to deform the substrate.

3 is a flow chart sequentially showing a substrate processing method according to a first embodiment of the present invention.

1 and 3, in the process of removing the photoresist, in operation S10, the atmospheric transfer robot 21 loads the substrate W from the cassette 12 into the process chamber 30. At this time, the process chamber 30 is at a loading / unloading pressure, that is, at atmospheric pressure, and the lift pin 32 of the heating chuck 31 takes over the substrate W from the atmospheric transfer robot 21 at the loading / unloading position. Receive. When the atmospheric pressure transfer robot 21 exits from the process chamber 30, the gate valve (not shown) closes the substrate entrance 22 in step S12.

Subsequently, in step S14, the process chamber 30 is changed to a basic air pressure lower than the substrate processing air pressure. For example, the basic pressure is 1 Torr or less, preferably 500 mmTorr or less. In step S16, the lift pin 32 moves downward to place the substrate W on the heating chuck 31. At this time, the heating chuck 31 is heated to a high temperature process temperature, but the heat transfer is very low because the process chamber 30 is in a very low basic air pressure state, so that the substrate W is not subjected to a thermal shock.

Subsequently, in step S18, the process chamber 30 is changed to a heated atmospheric pressure state higher than the substrate processing atmospheric pressure. For example, the heating pressure is 1 Torr or more, preferably 10 Torr or more. In this step, the change to the atmospheric pressure is changed by inputting the process gas into the process chamber 30. The process gas is, for example, O ₂ , N ₂ . In step S20, the process chamber 30 is maintained for a predetermined time so that the substrate W is heated to a process temperature, for example, approximately 250 ° C. by the heating chuck 31 using the process gas as a heat transfer medium.

When the heating of the substrate W is completed, the pressure of the process chamber 30 is changed to the substrate processing pressure in step S22. For example, the substrate processing pressure is 1 Torr. Subsequently, plasma is generated by the plasma reactor 40 in step S24, and plasma processing is performed on the substrate W for removing the photoresist. When the substrate processing is completed, the pressure of the process chamber 30 is changed to the loading / unloading pressure, that is, atmospheric pressure in step S26. And the board | substrate W is unloaded by the atmospheric pressure transport robot 21 in step S28.

In the substrate processing process described above, each step may be performed simultaneously or continuously. For example, step S14 and step S16 may be performed simultaneously or sequentially. However, it is preferable to proceed at the same time to reduce the substrate processing time.

The substrate processing method according to the first embodiment of the present invention as described above quickly seats the substrate W loaded into the process chamber 30 on the heating chuck 31, and together with the process chamber 30, a very low basic The pressure is reduced to prevent deformation of the substrate W due to thermal shock. In addition, a predetermined amount of process gas is injected into the process chamber 30 to increase the pressure of the process chamber 30 so that the substrate W is quickly and uniformly heated. At this time, since the injection into the process chamber 30 in advance can be obtained an excellent effect that can shorten the process progress time.

A substrate processing method according to the first embodiment of the present invention is also applied to a substrate processing system for removing photoresist as shown in FIG. Here, it is apparent that the process chamber 30 may further shorten the time of changing the loading / unloading pressure into the basic pressure because the process pressure is in progress.

(Example 2)

4 is a schematic view of a substrate processing system employing a substrate processing method according to a second embodiment of the present invention. 5 is a perspective view of the plasma reactor and the process chamber of FIG. 4, and FIG. 6 is a cross-sectional view of the plasma reactor of FIG. 5.

4 to 6, the substrate processing system according to the second embodiment of the present invention is basically the same as the configuration of the two systems described above. However, the plasma reactor 40 uses a plasma reactor 40 having a multiple discharge tube bridge capable of inducing a very strong plasma reaction capable of inducing a plasma reaction in the process chamber 30 even at a low atmospheric pressure. Thus, as will be described later, plasma is generated under low atmospheric pressure to heat the substrate to the process temperature prior to processing the substrate for removing the photoresist.

The plasma reactor 40 includes a hollow discharge tube head 40 disposed in the upper portion of the process chamber 30, a plurality of holes opened in the upper portion of the process chamber 30, and a plurality of holes formed in the lower portion of the discharge tube head 40. A plurality of hollow discharge tube bridges 42 and 43 connected between the holes, a ferrite core 45 mounted on the plurality of hollow discharge tube bridges 42 and 43, and a winding of the ferrite core 45 to supply a power source ( Consisting of an induction coil 71 connected to 70.

The plurality of hollow discharge tube bridges 42 are radially uniformly arranged on the upper surface of the process chamber 30, and one hollow discharge tube bridge 43 is positioned at the center thereof. The ferrite core 45 may be mounted to each hollow discharge tube bridge 43, and one hollow discharge tube bridge 43 positioned at the center may not be mounted with the ferrite core. Induction coils 46 mounted on the plurality of ferrite cores 45 are connected to a power supply 70 through an impedance matcher 71. The heating chuck 31 is connected to the power supply 73 through the impedance matcher 72.

Fig. 7 is a flowchart showing the substrate processing procedure in order according to the second embodiment of the present invention.

Referring to FIG. 7, in the process of removing the photoresist, the atmospheric transfer robot 21 loads the substrate W from the cassette 12 into the process chamber 30 in step S40. At this time, the process chamber 30 is at a loading / unloading pressure, that is, at atmospheric pressure, and the lift pin 32 of the heating chuck 31 takes over the substrate W from the atmospheric transfer robot 21 at the loading / unloading position. Receive. When the atmospheric pressure transfer robot 21 exits from the process chamber 30, the gate valve (not shown) closes the substrate entrance 22 in step S42.

Subsequently, in step S44, the process chamber 30 is changed to preliminary air pressure. For example, the preliminary air pressure is 10 Torr or less, preferably 500 mmTorr or less. In step S46, the lift pin 32 moves downward to place the substrate W on the heating chuck 31. At this time, the heating chuck 31 is heated to a high temperature process temperature, but the heat transfer is very low because the process chamber 30 is in a very low basic air pressure state, so that the substrate W is not subjected to a thermal shock.

Subsequently, the plasma reactor 40 is operated in step S48 to generate plasma on the substrate W. In step S50, the substrate W is heated to the process temperature by the generated plasma. The process temperature is, for example, allowed to heat up to approximately 250 ° C. After the substrate has been heated to the process temperature, in step S52 the process chamber is changed from preliminary air pressure to substrate processing air pressure. The change to the substrate processing pressure in this step is changed by inputting the process gas into the process chamber 30. For example, the substrate processing pressure is 1 Torr.

In step S54, plasma is maintained by the plasma reactor 40, and plasma processing is performed on the substrate W for removing the photoresist. When the substrate processing is completed, the pressure of the process chamber 30 is changed to the loading / unloading pressure, that is, atmospheric pressure in step S56. And the board | substrate W is unloaded by the atmospheric pressure transport robot 21 in step S58.

In the substrate processing process described above, each step may be performed simultaneously or continuously. For example, step S44 and step S46 may be performed simultaneously or sequentially. However, it is preferable to proceed at the same time to reduce the substrate processing time.

In the substrate processing method according to the second embodiment of the present invention as described above, the substrate W loaded into the process chamber 30 is quickly seated on the heating chuck 31, and the process chamber 30 is very low. The pressure is reduced to prevent deformation of the substrate W due to thermal shock. The plasma is generated on the substrate W so that the substrate W is heated quickly and uniformly. In addition, as the process gas is injected into the process chamber 30 while the plasma is generated, the substrate processing process is continuously performed, thereby obtaining an excellent effect of shortening the process progress time.

The substrate processing method according to the second embodiment of the present invention is also applied to the system as shown in FIG. Here, it is apparent that the process chamber 30 may further shorten the time of changing the loading / unloading pressure into the preliminary pressure due to the process pressure.

As described above, the present invention has been described with reference to the embodiments shown in the drawings, but this is merely exemplary, and those skilled in the art to which the present invention pertains have various modifications and equivalent embodiments. You can see that it is possible. That is, the same may be performed not only for removing a photoresist but also for a semiconductor manufacturing process requiring other substrate heating. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

According to the substrate processing method of the present invention as described above, by heating the substrate uniformly, it is possible to prevent the substrate from being deformed, thereby increasing the yield while increasing the yield of the substrate while improving the yield.

Claims (18)

1. A substrate processing method of a substrate processing system comprising a process chamber provided with a heating chuck and a plasma reactor: Loading the substrate to the lift pin of the heating chuck in the loading / unloading position at atmospheric pressure of the process chamber; Changing the air pressure of the process chamber to a base air pressure lower than a substrate processing pressure for plasma treating the substrate; The lift pin is lowered to move the substrate from the loading / unloading position to the substrate processing position above the heating chuck; Inputting a process gas for substrate processing into the process chamber to change the atmospheric pressure of the process chamber to a heating atmosphere higher than the substrate processing pressure; Heating the substrate to a process temperature at a heated atmosphere and at a substrate processing location; Changing the atmospheric pressure of the process chamber from the heating atmosphere to the substrate processing pressure and proceeding with the substrate processing process; And Lifting the lift pin to move the substrate to a loading / unloading position when the substrate processing process is complete, and the air pressure of the process chamber unloading the substrate out of the process chamber at the loading / unloading air pressure. . The method of claim 1, wherein the loading / unloading pressure is a substrate processing pressure. The method of claim 1, wherein the loading / unloading pressure is atmospheric pressure. delete delete delete delete delete delete delete 1. A substrate processing method of a substrate processing system comprising a process chamber provided with a heating chuck and a plasma reactor: Loading the substrate to the lift pin of the heating chuck in the loading / unloading position at atmospheric pressure of the process chamber; Changing the air pressure in the process chamber to a preliminary air pressure lower than the substrate processing air pressure for plasma treating the substrate; The lift pin is lowered to move the substrate from the loading / unloading position to the substrate processing position above the heating chuck; Operating a plasma reactor of the process chamber at a preliminary atmospheric pressure to generate a plasma; Heating the substrate to a process temperature by the generated plasma; Changing the air pressure of the process chamber from the preliminary air pressure to the substrate processing air pressure and proceeding with the substrate processing process; And Lifting the lift pins to move the substrate to the loading / unloading position when the substrate processing process is complete, and the air pressure of the process chamber unloading the substrate out of the process chamber at the loading / unloading air pressure. . The substrate processing method of claim 11, wherein the loading / unloading pressure is a substrate processing pressure. 12. The method of claim 11, wherein the loading / unloading pressure is atmospheric pressure. delete delete delete delete The method of claim 11, wherein the plasma reactor is: A hollow discharge tube head disposed above the process chamber; A plurality of hollow discharge tube bridges connected between the plurality of holes opened in the upper portion of the process chamber and the plurality of holes formed in the lower portion of the discharge tube head; A ferrite core mounted to the plurality of hollow discharge tube bridges; And A substrate processing method comprising an induction coil wound around a ferrite core and connected to a power supply.

Images