JP2022057019A - Plasma processing apparatus, and plasma processing method - Google Patents

Abstract

To provide a plasma processing apparatus capable of efficiently removing a fluorine compound deposited on a surface of an object to be processed, and a plasma processing method.SOLUTION: A plasma processing apparatus is capable of performing plasma processing on an object to be processed using a fluorine atom containing gas. The plasma processing apparatus comprises: a first chamber maintaining an atmosphere of which the pressure is reduced to be lower than an atmospheric pressure, and capable of internally holding the object to be processed to which a fluorine compound is deposited on a surface; an exhaust unit capable of reducing the pressure inside the first chamber down to a predetermined pressure; and a gas supply unit capable of supplying a water vapor containing gas to the object to be processed to which the fluorine compound is deposited, or to a region in which plasma is generated. The water vapor containing gas supplied to the region in which plasma is generated is excited by the generated plasma and supplied to the object to be processed to which the fluorine compound is deposited.SELECTED DRAWING: Figure 1

Description

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

Dry processes using plasma are utilized in a wide range of technical fields such as manufacturing of semiconductor devices, surface hardening of metal parts, surface activation of plastic parts, and chemical-free sterilization. For example, in the manufacture of semiconductor devices and flat panel displays, various plasma treatments such as etching treatment, ashing treatment, and removal of damage caused by etching treatment using ions are performed.

In such plasma treatment, the generated plasma excites and activates the process gas to generate plasma products such as radicals and ions. Then, plasma treatment is performed on the processed product using the generated radicals and ions. In this case, the process gas is appropriately selected according to the type of treatment, the material of the treated product, and the like. For example, in the case of etching treatment, a process gas containing a fluorine atom such as CF ₄ or CF ₃ is often used so that highly reactive radicals are generated.

However, when the etching treatment is performed using a process gas containing fluorine atoms, the fluorine compound may remain on the surface of the treated product after the treatment. In addition, the fluorine compound adhering to the inner wall of the chamber to be plasma-treated may adhere to the surface of the processed product after the treatment. In addition, the processed material that has been processed is stored in a storage unit such as a pod provided outside the chamber. In this case, if the fluorine compound adheres to the surface of the processed material conveyed from the chamber to the storage unit, the fluorine compound is released to the inside of the storage unit, and fluorine is released on the surface of the other processed material stored in the storage unit. Compounds may adhere.

If the fluorine compound adheres to the surface of the treated object, the fluorine compound may become an obstacle in the treatment performed after the etching treatment (for example, removal of damage caused by the etching treatment).
Therefore, in general, the treated product to which the fluorine compound is attached is washed with water to remove the fluorine compound. However, when the washing treatment is performed, the treatment time becomes long and the productivity is lowered. In addition, watermark may occur.

Further, a technique has been proposed in which a fluorine compound adhering to the surface of a processed product is removed by heating the processed product in an atmosphere of a gas containing a hydrogen atom. (See, for example, Patent Document 1).
However, when the heated processed material is carried out of the chamber and exposed to an atmosphere in which an oxygen-containing gas such as air is present, the surface of the processed material may be oxidized. In this case, if the processed material is kept waiting inside the chamber until the temperature of the heated processed material decreases, the processing time becomes long and the productivity decreases.

Therefore, it has been desired to develop a technique capable of efficiently removing the fluorine compound adhering to the surface of the processed product.

Japanese Unexamined Patent Publication No. 10-163127

An object to be solved by the present invention is to provide a plasma processing apparatus and a plasma processing method capable of efficiently removing a fluorine compound adhering to the surface of a processed product.

The plasma processing apparatus according to the embodiment is a plasma processing apparatus capable of plasma processing a processed material by using a gas containing a fluorine atom. A first chamber that maintains an atmosphere depressurized from atmospheric pressure and can hold the treated product having a fluorine compound on its surface inside, and an exhaust gas that can depressurize the inside of the first chamber to a predetermined pressure. A unit and a gas supply unit capable of supplying a gas containing water vapor to the processed product to which the fluorine compound is attached or to a region where plasma is generated are provided. The gas containing water vapor supplied to the region where the plasma is generated is excited by the generated plasma and supplied to the processed product to which the fluorine compound is attached.

According to the embodiment of the present invention, there is provided a plasma processing apparatus capable of efficiently removing the fluorine compound adhering to the surface of the processed product, and a plasma processing method.

It is a schematic cross-sectional view for exemplifying the plasma processing apparatus which concerns on this embodiment. It is a graph for exemplifying the effect of gas. It is a schematic cross-sectional view for exemplifying the plasma processing apparatus which concerns on other embodiment. It is a layout diagram for exemplifying the plasma processing apparatus which concerns on other embodiment. It is a schematic cross-sectional view for exemplifying a removal part.

Hereinafter, embodiments of the present invention will be illustrated with reference to the drawings. In each drawing, similar components are designated by the same reference numerals and detailed description thereof will be omitted as appropriate.
FIG. 1 is a schematic cross-sectional view for illustrating the plasma processing apparatus 1 according to the present embodiment. The plasma processing apparatus 1 illustrated in FIG. 1 is a microwave excitation type plasma processing apparatus generally called a “CDE (Chemical Dry Etching) apparatus” or a “remote plasma apparatus”. The plasma processing apparatus 1 generates a plasma product from a process gas using plasma P, and mainly processes the processed product W using radicals contained in the plasma product.

As shown in FIG. 1, the plasma processing apparatus 1 includes, for example, a plasma generation unit 2, an exhaust unit 3, a microwave generation unit 4, a chamber 5 (corresponding to an example of the first chamber), a gas supply unit 6, and a gas supply unit 6. , The controller 7 is provided.
The plasma generation unit 2 has, for example, a discharge tube 2a, an introduction waveguide 2b, and a transport tube 2c.
The discharge tube 2a has a region for generating plasma P inside, and is provided at a position separated from the chamber 5. The discharge tube 2a has a tubular shape and contains a material having a high transmittance for microwave M and being difficult to be etched. For example, the discharge tube 2a contains a dielectric such as alumina or quartz.

The introduction waveguide 2b is connected to the outside of the discharge tube 2a so as to be substantially orthogonal to the discharge tube 2a. A termination matcher 2b1 is provided at the end of the introduction waveguide 2b. Further, a stub tuner 2b2 is provided on the inlet side (introduction side of the microwave M) of the introduction waveguide 2b.

An annular slot 2b3 is provided at the connection portion between the introduction waveguide 2b and the discharge tube 2a. The microwave M propagating inside the introduction waveguide 2b is radiated into the inside of the discharge tube 2a via the slot 2b3.

One end of the transport pipe 2c is connected to the end of the discharge pipe 2a on the side opposite to the gas supply part 6 side. The other end of the transport pipe 2c is connected to the chamber 5. The transport tube 2c is formed of a material that is resistant to radicals contained in the plasma product. The transport pipe 2c is formed of, for example, quartz, stainless steel, ceramics, fluororesin, or the like.

The exhaust unit 3 is connected to, for example, the bottom surface of the chamber 5. Further, a pressure control unit (Auto Pressure Controller) 3a can be provided between the exhaust unit 3 and the chamber 5. The exhaust unit 3 decompresses the inside of the chamber 5 to a predetermined pressure. The exhaust unit 3 is, for example, a dry pump, a turbo molecular pump (TMP), or the like.

The microwave generation unit 4 is provided at the end of the introduction waveguide 2b on the side opposite to the discharge tube 2a side. The microwave generation unit 4 generates a microwave M having a predetermined frequency (for example, 2.75 GHz) and radiates it toward the introduction waveguide 2b.

The chamber 5 has an airtight structure capable of maintaining an atmosphere depressurized from atmospheric pressure. Inside the chamber 5, a mounting portion 5a containing an electrostatic chuck (not shown) is provided. The processed object W (for example, a semiconductor wafer, a glass substrate, etc.) is placed on the mounting portion 5a. Therefore, the chamber 5 can hold the processed product W in which the fluorine compound is attached to the surface Wa.

Further, a straightening vane 5b is provided inside the chamber 5. The straightening vane 5b is provided on the inner wall of the chamber 5 so as to be substantially parallel to the mounting surface of the mounting portion 5a. A gas containing radicals or a gas G2 containing water vapor, which will be described later, is introduced into the space between the straightening vane 5b and the ceiling of the chamber 5 via the transport pipe 2c. If the straightening vane 5b is provided, it becomes easy to make the amount of radicals or the amount of water vapor on the surface Wa of the processed material W substantially uniform.

Further, the side wall of the chamber 5 is provided with an opening 5c for carrying in and out of the processed material W. Further, a door 5d for opening and closing the opening 5c is provided. A load lock portion 5e having a chamber 5e1 (corresponding to an example of the first chamber) is provided in a portion where the opening 5c is provided. Since a known technique can be applied to the load lock portion 5e, detailed description thereof will be omitted.

The gas supply unit 6 is connected to the end of the discharge pipe 2a on the side opposite to the chamber 5 side. The gas supply unit 6 can switch between the supply of the gas G1 and the supply of the gas G2. Further, a pressure control unit 6a is provided between the gas supply unit 6 and the discharge pipe 2a. The pressure control unit 6a controls the pressure of the gas G1 supplied to the inside of the discharge pipe 2a and the pressure of the gas G2. It is also possible to separately provide a gas supply unit for supplying the gas G1 and a gas supply unit for supplying the gas G2. A pressure control unit that controls the pressure of the gas G1 and a pressure control unit that controls the pressure of the gas G2 may be provided separately.

The gas G1 can be a so-called process gas. The gas G1 is appropriately selected depending on the material of the surface Wa of the processed product W. For example, in the case of etching treatment, the gas G1 containing fluorine atoms such as CF ₄ and CF ₃ can be used so that highly reactive radicals are generated. For example, the gas G1 can be only _CF4 . Further, the gas G1 can also be a mixed gas in which a reactive gas such as oxygen gas or nitrogen gas is mixed with CF ₄ . Further, the gas G1 can also be a mixed gas in which a rare gas such as argon gas or helium gas is mixed with CF ₄ .

The gas G2 contains water vapor. For example, the gas G2 can be only water vapor. Further, the gas G2 can further contain a carrier gas. The carrier gas is preferably a gas having low reactivity. The carrier gas can be, for example, nitrogen gas. Further, the carrier gas may be a rare gas such as argon gas or helium gas.

The gas G2 can be supplied to the inside of the chamber 5 after being excited and activated by the plasma P, or the gas G2 can be supplied to the inside of the chamber 5 as it is.
When the gas G2 is supplied to the inside of the chamber 5 as it is, the microwave M is not generated in the microwave generating unit 4. Further, the gas G2 can be supplied to the inside of the transport pipe 2c or the inside of the chamber 5. Further, as will be described later, the gas G2 can also be supplied to the inside of the chamber 5e1 of the load lock portion 5e.
For example, the gas supply unit 6 supplies the gas G2 containing water vapor to the processed product W to which the fluorine compound described later is attached or to the region where the plasma P is generated. The gas G2 containing water vapor supplied to the region where the plasma P is generated is excited by the generated plasma P and supplied to the processed product W to which the fluorine compound is attached.

The controller 7 has, for example, a calculation unit such as a CPU (Central Processing Unit) and a storage unit such as a memory. The controller 7 is, for example, a computer or the like. The controller 7 controls the operation of each element provided in the plasma processing apparatus 1 based on, for example, a control program stored in the storage unit.

Next, the operation of the plasma processing apparatus 1 will be described.
First, plasma treatment is performed on the processed material W using the gas G1.
First, the processed object W is carried into the inside of the chamber 5 by a transfer device (not shown), and is placed and held on the mounting portion 5a.
Next, the inside of the chamber 5 is depressurized to a predetermined pressure by the exhaust unit 3. At this time, the pressure inside the chamber 5 is controlled by the pressure control unit 3a. Further, the inside of the discharge tube 2a communicating with the chamber 5 is also depressurized.

Next, the plasma product is generated by the plasma generating unit 2. For example, a gas G1 (for example, CF ₄ or the like) having a predetermined pressure is supplied from the gas supply unit 6 to the inside of the discharge pipe 2a via the pressure control unit 6a. Further, a microwave M having a predetermined power is radiated from the microwave generation unit 4 to the inside of the introduction waveguide 2b. The radiated microwave M propagates inside the introduced waveguide 2b and is radiated into the inside of the discharge tube 2a via the slot 2b3.

Plasma P is generated by the energy of microwave M radiated inside the discharge tube 2a. The generated plasma P excites and activates the gas G1 to generate a plasma product containing radicals, ions, and the like.

The gas containing the plasma product is supplied to the inside of the chamber 5 via the transport pipe 2c. At this time, ions having a short life cannot reach the inside of the chamber 5, and radicals having a long life reach the inside of the chamber 5. The gas containing radicals supplied to the inside of the chamber 5 is rectified by the rectifying plate 5b and reaches the surface Wa of the processed object W, and plasma treatment such as etching treatment is performed. In this case, radical chemical treatment is mainly performed. Further, since the ions used for the physical treatment are not supplied to the inside of the chamber 5, the surface Wa of the processed material W is not damaged by the ions. Therefore, the plasma processing apparatus 1 is suitable for removing damage caused by, for example, an etching process using ions.

Here, when the gas G1 containing a fluorine atom such as CF ₄ is used, the fluorine compound may adhere to the surface Wa of the processed product W. For example, the fluorine compound generated by the plasma treatment may remain on the surface Wa of the treated product W. In addition, the fluorine compound generated by the plasma treatment and adhering to the inner wall of the chamber 5 may adhere to the surface Wa of the processed product W. Further, the processed material W that has been processed is discharged from the chamber 5 and stored in a storage unit such as a pod. When the fluorine compound adheres to the surface Wa of the processed material W carried into the storage portion, the fluorine compound is released to the inside of the storage portion, and the fluorine compound is released to the surface Wa of the other processed material W stored in the storage portion. May adhere.

If the fluorine compound adheres to the surface Wa of the processed product W, the fluorine compound may be an obstacle in the treatment performed after the etching treatment.

Therefore, next, the gas G2 is used to remove the fluorine compound adhering to the surface Wa of the treated product W.
First, the gas G2 having a predetermined pressure is supplied from the gas supply unit 6 to the inside of the discharge pipe 2a via the pressure control unit 6a. The gas G2 supplied to the inside of the discharge pipe 2a is supplied to the surface Wa of the processed product W via the transport pipe 2c and the straightening vane 5b. In this case, as described above, the gas G2 can be supplied to the inside of the transport pipe 2c or the inside of the chamber 5. Further, the gas G2 supplied to the inside of the discharge tube 2a may be excited and activated by the plasma P. The excited and activated gas G2 is supplied to the processed product W to which the fluorine compound is attached.

In this case, since the gas G2 and the excited and activated gas G2 are supplied to the inside of the chamber 5, the fluorine compound adhering to the inner wall of the chamber 5 can also be removed. The fluorine compound removed from the surface Wa of the processed material W and the inner wall of the chamber 5 is discharged to the outside of the chamber 5 by the exhaust unit 3.

The processed material W, which has been processed, is carried out from the chamber 5 by a transfer device (not shown). After that, if necessary, the next processed material W is carried into the chamber 5 and the above-mentioned processing is performed.

FIG. 2 is a graph for exemplifying the effect of gas G2.
“A1” in FIG. 2 is a case where the supply pressure of the gas G2 is 500 Pa and the temperature of the gas G2 is 25 ° C. “A2” is a case where the supply pressure of the gas G2 is 1000 Pa and the temperature of the gas G2 is 25 ° C. “A3” is a case where the supply pressure of the gas G2 is 1000 Pa and the temperature of the gas G2 is 100 ° C. “B” is a case where the supply pressure of the gas G2 is 1000 Pa, the temperature of the gas G2 is 25 ° C., and the gas G2 is excited and activated by the plasma P.

As can be seen from "A1" and "A2", if the supply pressure of the gas G2 is increased, the supply amount of the gas G2 increases, so that the removal rate of the fluorine compound adhering to the surface Wa of the processed product W is improved. be able to.
As can be seen from "A2" and "A3", when the temperature of the gas G2 is increased, the removal rate of the fluorine compound adhering to the surface Wa of the processed product W decreases.

According to the knowledge obtained by the present inventor, it is preferable that the supply pressure of the gas G2 is 1000 Pa or more and 2000 Pa or less, and the temperature of the gas G2 is 20 ° C. or more and 25 ° C. or less. By doing so, the fluorine compound adhering to the surface Wa of the treated product W can be efficiently removed.

Furthermore, as can be seen from "A2" and "B", if the gas G2 is excited and activated by the plasma P, the fluorine compound adhering to the surface Wa of the processed product W can be removed more efficiently. can.

FIG. 3 is a schematic cross-sectional view for illustrating the plasma processing apparatus 11 according to another embodiment.
The plasma processing apparatus 11 illustrated in FIG. 3 is a capacitively coupled plasma (CCP) processing apparatus generally called a “parallel plate type RIE (Reactive Ion Etching) apparatus”. The plasma processing apparatus 11 generates a plasma product from the process gas using the plasma P, and processes the processed product W using the ions and radicals contained in the plasma product.

As shown in FIG. 3, the plasma processing apparatus 11 includes, for example, a plasma generation unit 12, an exhaust unit 3, a power supply unit 14, a chamber 15 (corresponding to an example of the first chamber), a gas supply unit 6, and a controller 7. I have.
The chamber 15 has an airtight structure capable of maintaining an atmosphere depressurized from atmospheric pressure. An opening 15a for carrying in and out of the processed material W is provided on the side wall of the chamber 15 and the like. Further, a door 15b for opening and closing the opening 15a is provided. A load lock portion 15c having a chamber 15c1 (corresponding to an example of the first chamber) is provided in a portion where the opening 15a is provided. Since a known technique can be applied to the load lock portion 15c, detailed description thereof will be omitted.

The plasma generating unit 12 has, for example, a lower electrode 12a and an upper electrode 12b.
The lower electrode 12a is provided inside the chamber 15. The lower electrode 12a can be provided on the bottom surface of the chamber 15. The lower electrode 12a functions as a mounting portion on which the discharge electrode and the processed object W are placed.
The upper electrode 12b faces the lower electrode 12a. The upper electrode 12b can be grounded, for example.

The power supply unit 14 has, for example, a high frequency power supply 14a and a blocking capacitor 14b. The high frequency power supply 14a is electrically connected to the lower electrode 12a via the blocking capacitor 14b. The high frequency power supply 14a applies high frequency power of about 100 KHz to 100 MHz to the lower electrode 12a. The blocking capacitor 14b is provided to prevent the movement of electrons generated in the plasma P and reaching the lower electrode 12a.

Next, the operation of the plasma processing device 11 will be described.
First, plasma treatment is performed on the processed material W using the gas G1.
First, the processed object W is carried into the chamber 15 by a transfer device (not shown), and is placed and held on the lower electrode 12a.

Next, the inside of the chamber 15 is depressurized to a predetermined pressure by the exhaust unit 3. At this time, the pressure inside the chamber 15 is controlled by the pressure control unit 3a.

Next, the plasma product is generated by the plasma generating unit 12. For example, a gas G1 (for example, CF ₄ ) having a predetermined pressure is supplied from the gas supply unit 6 to a region inside the chamber 15 where plasma P is generated via the pressure control unit 6a.

Further, high frequency power of about 100 KHz to 100 MHz is applied to the lower electrode 12a from the power supply unit 14 (high frequency power supply 14a). Since the lower electrode 12a and the upper electrode 12b form a parallel plate electrode, a discharge occurs between the electrodes and plasma P is generated. The generated plasma P excites and activates the gas G1 to generate plasma products such as radicals, ions, and electrons. The generated plasma product descends inside the chamber 15 and reaches the surface Wa of the processed product W, and plasma treatment such as etching treatment is performed.

In this case, among the generated ions and electrons, the electron having a light mass moves quickly and reaches the lower electrode 12a and the upper electrode 12b immediately. The electrons that reach the lower electrode 12a are blocked from moving by the blocking capacitor 14b, so that the lower electrode 12a is charged. The band voltage of the lower electrode 12a reaches about 400V to 1000V, which is called "cathode drop". On the other hand, since the upper electrode 12b is grounded, the arriving electrons are not blocked from moving, and the upper electrode 12b is hardly charged.

Then, the ions move toward the lower electrode 12a (processed object W) along the vertical electric field generated by the cathode drop, and are incident on the surface Wa of the processed object W. Therefore, physical treatment with ions is applied to the surface Wa of the processed material W. Further, the radical descends due to the gas flow or gravity and reaches the surface Wa of the processed product W. Therefore, chemical treatment with radicals is also performed. The plasma processing apparatus 11 that performs physical treatment with ions is suitable for forming trenches, holes, and the like on the surface Wa of the processed material W.

Here, as in the case of the plasma processing apparatus 1 described above, when the gas G1 containing a fluorine atom such as CF ₄ is used, the fluorine compound adheres to the surface Wa of the processed product W.
Therefore, also in the case of the plasma processing apparatus 11, the gas G2 is used to remove the fluorine compound adhering to the surface Wa of the processed product W.

First, gas G2 having a predetermined pressure is supplied from the gas supply unit 6 to the inside of the chamber 15 via the pressure control unit 6a. The gas G2 supplied to the inside of the chamber 15 descends inside the chamber 15 and is supplied to the surface Wa of the processed object W.
Further, the gas G2 supplied to the inside of the chamber 15 may be excited and activated by the plasma P. The excited and activated gas G2 is supplied to the processed product W to which the fluorine compound is attached.

Further, since the gas G2 and the excited and activated gas G2 are supplied to the inside of the chamber 15, the fluorine compound adhering to the inner wall of the chamber 15 can also be removed. The fluorine compound removed from the surface Wa of the processed material W and the inner wall of the chamber 15 is discharged to the outside of the chamber 15 by the exhaust unit 3.
The effect of gas G2 is as described in FIG.

The processed material W, which has been processed, is carried out from the chamber 15 by a transfer device (not shown). After that, if necessary, the next processed product W is carried into the chamber 15 and the above-mentioned processing is performed.

In the above, the capacitive coupling type plasma processing apparatus represented by the CDE apparatus (remote plasma apparatus) and the parallel plate type RIE apparatus has been exemplified, but the plasma processing apparatus according to the present invention is limited to these plasma processing apparatus. Not done. The present invention can be applied to a plasma processing apparatus that can use a process gas containing a fluorine atom. For example, the plasma processing apparatus according to the present invention is a microwave-excited plasma processing apparatus called "SWP (Surface Wave Plasma) apparatus", "Inductively Coupled Plasma (ICP)", "Inductively Coupled Plasma (ICP)". It may be a dual frequency plasma processing apparatus having an inductively coupled electrode at the upper part and a capacitively coupled electrode at the lower part. Since known techniques can be applied to the basic configuration of these plasma processing devices, detailed description thereof will be omitted.

FIG. 4 is a layout diagram for exemplifying the plasma processing apparatus 21 according to another embodiment.
As shown in FIG. 4, the plasma processing device 21 includes, for example, a storage unit 21a, a transport unit 21b, a load lock unit 21c, a transfer unit 21d, a processing unit 21e, and a controller 27.

The controller 27 has, for example, a calculation unit such as a CPU (Central Processing Unit) and a storage unit such as a memory. The controller 27 is, for example, a computer. The controller 27 controls the operation of each element provided in the plasma processing device 21, for example, based on the control program stored in the storage unit.

The storage unit 21a stores, for example, the processed material W in a laminated shape (multi-stage shape). The storage portion 21a is, for example, a so-called pod, a FOUP (Front-Opening Unified Pod) which is a front opening type carrier, or the like. However, the storage unit 21a is not limited to the one illustrated, and may be any storage unit W as long as it can store the processed material W. At least one storage unit 21a is provided.

The transport portion 21b is provided between the storage portion 21a and the load lock portion 21c. The transport section 21b transports and delivers the processed object W between the storage section 21a and the load lock section 21c. In this case, the transport unit 21b transports and delivers the processed product W in an environment where the pressure is higher than the pressure at which the plasma treatment is performed (for example, atmospheric pressure). The transport unit 21b is, for example, a transport robot having an arm.

The load lock portion 21c is provided between the transport portion 21b and the delivery portion 21d. The load lock unit 21c transfers the processed material W between the transport unit 21b and the processing unit 21e, which have different atmospheric pressures. Therefore, the load lock unit 21c has a chamber 21c1 (corresponding to an example of the first chamber), an exhaust unit 21c3, and a gas supply unit 21c2. The exhaust section 21c3 makes the pressure inside the load lock section 21c substantially equal to the pressure inside the chamber 21d1 of the transfer section 21d. The gas supply unit 21c2 supplies gas to the inside of the load lock unit 21c so that the pressure inside the load lock unit 21c becomes substantially equal to the pressure of the transport unit 21b.

The delivery section 21d is provided between the processing section 21e and the load lock section 21c. The delivery unit 21d transfers the processed object W between the processing unit 21e and the load lock unit 21c. The delivery section 21d includes a chamber 21d1 (corresponding to an example of the first chamber), a transfer section 21d2 provided inside the chamber 21d1, and an exhaust section 21d3 for reducing the pressure inside the chamber 21d1 to a predetermined pressure. The transport unit 21d2 is, for example, a transport robot having an arm.

Since known techniques can be applied to the storage unit 21a, the transport unit 21b, the load lock unit 21c, and the delivery unit 21d, detailed description thereof will be omitted. Further, since known techniques can be applied to the transfer procedure of the processed material W and the plasma processing procedure in the storage unit 21a, the transport unit 21b, the load lock unit 21c, the transfer unit 21d, and the processing unit 21e. , Detailed explanation is omitted.

The processing unit 21e has a plasma processing unit 21e1 and a removing unit 21e2. At least one plasma processing unit 21e1 is provided. At least one removing unit 21e2 is provided.
The plasma processing unit 21e1 performs plasma treatment on the processed material W in an atmosphere in which the pressure is lower than the atmospheric pressure. The plasma processing unit 21e1 may be provided with, for example, the gas supply unit for supplying the gas G2 removed from the plasma processing devices 1 and 11 described above, and only the gas supply unit for supplying the gas G1 is provided. That is, the plasma processing unit 21e1 may be any plasma processing apparatus that can use a process gas containing a fluorine atom. Therefore, the configuration of the plasma processing unit 21e1 can be the same as that described above, and detailed description thereof will be omitted.

The removing unit 21e2 removes the fluorine compound adhering to the surface Wa of the processed product W in an atmosphere depressurized from atmospheric pressure.
When the gas G2 is supplied to the inside of the chamber (corresponding to an example of the second chamber) 21e1a of the plasma processing unit 21e1 to remove the fluorine compound, the next processed product is sent to the plasma processing unit 21e1 during the removal. W cannot be carried in. Further, it is necessary to discharge the gas G2 from the inside of the chamber 21e1a before performing the plasma treatment on the next processed object W. If the plasma processing unit 21e1 and the removing unit 21e2 are separated, the next processed material W can be carried into the plasma processing unit 21e1 without waiting for the fluorine compound to be removed from the processed material W after the plasma treatment. can. Further, it is not necessary to discharge the gas G2 from the inside of the chamber 21e1a before performing the plasma treatment on the next processed object W. Therefore, if the removal unit 21e2 is provided, the throughput can be improved.

FIG. 5 is a schematic cross-sectional view for illustrating the removal portion 21e2.
As shown in FIG. 5, the removing unit 21e2 includes, for example, an exhaust unit 3, a chamber 21e2a (corresponding to an example of the first chamber), and a gas supply unit 26.
The chamber 21e2a has an airtight structure capable of maintaining an atmosphere depressurized from atmospheric pressure.
The exhaust unit 3 decompresses the inside of the chamber 21e2a to a predetermined pressure.

The gas supply unit 26 supplies the gas G2 to the inside of the chamber 21e2a. A pressure control unit 26a is provided between the gas supply unit 26 and the chamber 21e2a. The pressure control unit 26a controls the pressure of the gas G2 supplied to the inside of the chamber 21e2a.

In this case, it is preferable that the gas supply unit 26 is provided at a position where the gas G2 can be supplied toward the surface Wa of the processed product W. For example, as shown in FIG. 5, the gas supply unit 26 can supply the gas G2 toward the center of the mounting surface of the mounting unit 5a. By doing so, the gas G2 can be directly supplied to the surface Wa of the treated product W, so that the removal rate of the fluorine compound can be improved.
The effect of gas G2 is as described in FIG.

Further, it is preferable that the internal volume of the chamber 21e2a is smaller than the internal volume of the chamber 21e1a of the plasma processing unit 21e1. By doing so, the utilization efficiency of the gas G2 can be improved, and by extension, the consumption amount of the gas G2 can be reduced.

Further, the removing unit 21e2 stops the supply of the gas G2 after removing the fluorine compound. Then, the gas G2 is discharged to about the pressure of the load lock portion 21c when the processed object W is conveyed from the load lock portion 21c to the delivery portion 21d. As a result, the amount of gas G2 flowing into the delivery unit 21d can be reduced. Therefore, the exhaust speed of the delivery unit 21d can be maintained.

In the above description, the fluorine compound adhering to the surface Wa of the processed material W is removed in the chambers 5 and 15 that perform the plasma treatment and the chamber 21e2a of the removing unit 21e2. However, the removal of the fluorine compound may be carried out in an atmosphere in which the pressure is lower than the atmospheric pressure.

For example, in the case of the plasma processing apparatus 21, gas G2 is supplied to at least one of the chamber 21c1 of the load lock portion 21c and the chamber 21d1 of the transfer portion 21d, and adheres to the surface Wa of the processed product W. Fluorine compounds may be removed.

For example, since the above-mentioned plasma processing devices 1 and 11 are also provided with the load lock portion 5e having the chamber 5e1 and the load lock portion 15c having the chamber 15c1, the gas G2 is supplied to the chambers 5e1 and 15c to supply the processed product W. The fluorine compound adhering to the surface Wa of the plasma may be removed.

As described above, the plasma treatment method according to the present embodiment can have the following steps.
A step of plasma-treating a processed product W using a gas G1 containing a fluorine atom.
A step of removing the fluorine compound adhering to the surface Wa of the processed product W.
In the step of removing the fluorine compound, the gas G2 containing water vapor is supplied to the processed product W to which the fluorine compound is attached or to the region where the plasma P is generated.
The gas G2 containing water vapor supplied to the region where the plasma P is generated is excited by the generated plasma P and supplied to the processed product W to which the fluorine compound is attached.

The temperature of the gas G2 containing water vapor is 20 ° C. or higher and 25 ° C. or lower.
The supply pressure of the gas G2 containing water vapor is 1000 Pa or more and 2000 Pa or less.

The present embodiment has been illustrated above. However, the present invention is not limited to these descriptions.
The above-mentioned embodiments which have been appropriately designed by those skilled in the art are also included in the scope of the present invention as long as they have the features of the present invention.
For example, the shape, size, material, arrangement, number, and the like of each element included in the plasma processing devices 1, 11, and 21 are not limited to those illustrated, and can be appropriately changed.
Further, the elements included in each of the above-described embodiments can be combined as much as possible, and the combination thereof is also included in the scope of the present invention as long as the features of the present invention are included.

1 Plasma processing device, 2 Plasma generating section, 3 Exhaust section, 5 Chamber, 5e load lock section, 6 Gas supply section, 11 Plasma processing device, 12 Plasma generating section, 15 Chamber, 15c load lock section, 21 Plasma processing device, 21c load lock part, 21d transfer part, 21e processing part, 21e1 plasma processing part, 21e2 removal part, 21e2a chamber, 26 gas supply part, G1 gas, G2 gas, P plasma, W processed material, Wa surface

Claims (9)

A plasma processing device capable of plasma processing a processed product using a gas containing fluorine atoms.
A first chamber capable of maintaining an atmosphere depressurized from atmospheric pressure and holding the treated product having a fluorine compound attached to the surface inside.
An exhaust unit that can reduce the pressure inside the first chamber to a predetermined pressure,
A gas supply unit capable of supplying a gas containing water vapor to the treated product to which the fluorine compound is attached or to a region where plasma is generated.
Equipped with
A plasma processing apparatus in which the gas containing water vapor supplied to the region where plasma is generated is excited by the generated plasma and supplied to the processed product to which the fluorine compound is attached. The plasma processing apparatus according to claim 1, wherein the region for generating plasma is provided inside the first chamber or at a position separated from the first chamber. With a second chamber
The region for generating the plasma is provided inside the second chamber or at a position separated from the second chamber.
The plasma processing apparatus according to claim 1, wherein the gas supply unit supplies a gas containing water vapor to a processed product to which the fluorine compound is attached, which is held inside the first chamber. Further equipped with a load lock part,
The first chamber is provided in the load lock portion, and the first chamber is provided in the load lock portion.
The plasma processing apparatus according to claim 1, wherein the gas supply unit supplies a gas containing water vapor to a processed product to which the fluorine compound is attached, which is held inside the first chamber. The plasma processing apparatus according to any one of claims 1 to 4, wherein the temperature of the gas containing water vapor is 20 ° C. or higher and 25 ° C. or lower. The plasma processing apparatus according to any one of claims 1 to 5, wherein the supply pressure of the gas containing water vapor is 1000 Pa or more and 2000 Pa or less. The process of plasma-treating the processed product using a gas containing fluorine atoms,
The step of removing the fluorine compound adhering to the surface of the treated product, and
Equipped with
In the step of removing the fluorine compound, a gas containing water vapor is supplied to the treated product to which the fluorine compound is attached or to a region where plasma is generated.
A plasma treatment method in which the gas containing water vapor supplied to the region where plasma is generated is excited by the generated plasma and supplied to the processed product to which the fluorine compound is attached. The plasma treatment method according to claim 7, wherein the temperature of the gas containing water vapor is 20 ° C. or higher and 25 ° C. or lower. The plasma treatment method according to claim 7 or 8, wherein the supply pressure of the gas containing water vapor is 1000 Pa or more and 2000 Pa or less.

Images