Substrate processing device, substrate processing method and method of manufacturing semiconductor device

Abstract

To provide a substrate processing device, a substrate processing method and a method of manufacturing a semiconductor device capable of realizing a high throughput in substrate processing using a plasma.SOLUTION: A plasma processing unit has: a reaction container; a resonance coil provided on a side wall outer periphery of the reaction container; a gas introduction port 433 provided on a top plate 454 of the reaction container; baffle plates 460a, 460b provided inside the reaction container between the gas introduction port and the upper end of the resonance coil, so as to have a gap from the upper end surface of the container; and a fixing mechanism comprising a bolt 491 inserted into the top plate, and a section corresponding to the gap being formed by metallic collars 492, 493 and a fixing bolt 494 and fixing the baffle plates to the top plate.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus, a substrate processing method, and a method for manufacturing a semiconductor device.

Background Art

[0002] When manufacturing a semiconductor device, various processes are performed using plasma. One method of generating plasma is the so-called inductive coupling method (ICP (Inductive Coupling Plasma) method). In the ICP method, an electric field is formed in the plasma generation space by supplying high-frequency power to a coil, and the gas supplied to that space is made into a plasma state. As a substrate processing apparatus using the ICP method, there is an apparatus such as Patent Document 1, for example.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in conventional substrate processing apparatuses, it has been difficult to generate high-density plasma, and as a result, there has been a problem that the throughput of substrate processing is low.

[0005] An object of the present invention is to provide a substrate processing apparatus and a method for manufacturing a semiconductor device capable of performing high-throughput substrate processing in plasma-based substrate processing.

Means for Solving the Problems

[0006] The present invention provides a reaction vessel, a coil provided on the outer periphery of the side wall of the reaction vessel, A gas inlet provided on the upper end surface of the inner side of the reaction vessel, A baffle portion provided in the reaction vessel between the gas inlet and the upper end of the coil, and having a gap with the upper end surface of the vessel, A fixing mechanism in which a section corresponding to the gap is constituted by a metal collar and the baffle portion is fixed to the upper end surface of the vessel, and a technique having the same is provided.

Advantages of the Invention

[0007] According to the present invention, it becomes possible to perform substrate processing with high throughput.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0009] Next, a preferred embodiment of the present invention will be described with reference to the drawings. The present invention relates to a substrate processing method used, for example, in a semiconductor manufacturing apparatus. In particular, the present invention relates to a dry etching process in which a reactive gas is made into a plasma state by an ICP method, and a predetermined organic thin film (resist, resist film) on the substrate surface is peeled off by reactive species (reactive active species) having high reactivity obtained thereby.

[0010] In a preferred embodiment of the present invention, a semiconductor device manufacturing method and a substrate processing method are realized by an ashing apparatus used as a semiconductor manufacturing apparatus and a substrate processing apparatus. FIG. 1 is a schematic cross-sectional view for explaining an ashing apparatus according to a preferred embodiment of the present invention, and FIG. 2 is a schematic longitudinal sectional view for explaining the ashing apparatus according to the preferred embodiment of the present invention. As shown in FIGS. 1 and 2, the ashing apparatus 10 includes an EFEM (Equipment Front End Module) 100, a load lock chamber section 200, a transfer module section 300, and a process chamber section 400 used as a processing chamber where ashing processing is performed.

[0011] The EFEM 100 includes FOUPs (Front Opening Unified Pods) 110 and 120 and an atmospheric robot 130 which is a first transfer unit for transferring wafers from each FOUP to the load lock chamber. Twenty-five wafers are loaded in the FOUP, and the arm portion of the atmospheric robot 130 extracts five wafers at a time from the FOUP.

[0012] The load lock chamber section 200 includes load lock chambers 250 and 260, and buffer units 210 and 220 that respectively hold the wafers 600 conveyed from the FOUP within the load lock chambers 250 and 260. The buffer units 210 and 220 include boats 211 and 221 and index assemblies 212 and 222 below them. The boat 211 and the index assembly 212 below it rotate simultaneously by a θ axis 214. Similarly, the boat 221 and the index assembly 222 below it rotate simultaneously by a θ axis 224.

[0013] The transfer module section 300 includes a transfer module 310 used as a transfer chamber, and the aforementioned load lock chambers 250 and 260 are attached to the transfer module 310 via gate valves 311 and 312. A vacuum arm robot unit 320 used as a second transfer unit is provided in the transfer module 310.

[0014] The process chamber section 400 includes plasma processing units 410 and 420 used as processing chambers, and plasma generation chambers 430 and 440 provided above them. The plasma processing units 410 and 420 are attached to the transfer module 310 via gate valves 313 and 314.

[0015] The plasma processing units 410 and 420 include susceptor tables 411 and 421 on which the wafers 600 are placed. Lifter pins 413 and 423 are provided penetrating the susceptor tables 411 and 421 respectively. The lifter pins 413 and 423 move up and down in the directions of Z axes 412 and 422 respectively.

[0016] The plasma generation chambers 430 and 440 respectively include reaction vessels 431 and 441. Outside the reaction vessels 431 and 441, a resonance coil (to be described later) is provided. High-frequency power is applied to the resonance coil to turn the reaction gas for ashing, which is introduced from the gas inlet (to be described later), into a plasma state. Using the plasma, the resist on the wafer 600 placed on the susceptor tables 411 and 421 is ashed (plasma processed).

[0017] Furthermore, it has a controller 500 that is electrically connected to each component. The controller 500 controls the operation of each component.

[0018] In the ashing apparatus 10 configured as described above, the wafers 600 are transported from the FOUPs 110 and 120 to the load lock chambers 250 and 260, respectively. At this time, first, as shown in FIG. 2, the atmospheric robot 130 stores the tweezers in the pod of the FOUP and places five wafers on the tweezers. At this time, the tweezers and the arm of the atmospheric robot are moved up and down according to the height position of the wafer to be taken out. After placing the wafers on the tweezers, the atmospheric transfer robot 130 rotates in the direction of the θ axis 131 and mounts the wafers on the boats 211 and 221 of the buffer units 210 and 220, respectively. At this time, by the operation of the boats 211 and 221 in the direction of the Z axis 230, the boats 211 and 221 receive 25 wafers 600 from the atmospheric transfer robot 130, respectively. After receiving 25 wafers, the boats 211 and 221 are operated in the direction of the Z axis 230 so that the wafers in the lowermost layer of the boats 211 and 221 match the height position of the transfer module unit 300.

[0019] In the load lock chambers 250 and 260, the wafers 600 held by the buffer units 210 and 220 in the load lock chambers 250 and 260 are mounted on the fingers 321 of the vacuum arm robot unit 320. The vacuum arm robot unit 320 is rotated in the direction of the θ axis 325, and the fingers are further extended in the direction of the Y axis 326 and transferred onto the susceptor tables 411 and 421 in the plasma processing units 410 and 420, respectively.

[0020] Here, the operation of the ashing apparatus 10 when transferring the wafer 600 from the fingers 321 to the susceptor tables 411 and 421 will be described.

[0021] By the cooperation of the fingers 321 of the vacuum arm robot unit 320 and the lifter pins 413 and 423, the wafer 600 is transferred onto the susceptor tables 411 and 421, respectively. Also, by the reverse operation, the processed wafer 600 is transferred from the susceptor tables 411 and 421 to the buffer units 210 and 220 in the load lock chambers 250 and 260 by the vacuum arm robot unit 320, respectively.

[0022] FIG. 3 is a diagram showing the details of the plasma processing unit 410. Note that the above-described plasma processing unit 420 has the same configuration as the plasma processing unit 410. Also, the above-described susceptor table 421 of the plasma processing unit 420 has the same configuration as the susceptor table 411.

[0023] The plasma processing unit 410 is an ICP-type plasma processing unit that performs ashing on semiconductor substrates and semiconductor elements by dry processing. As shown in FIG. 3, the plasma processing unit 410 includes a plasma generation chamber 430 for generating plasma, a processing chamber 445 for accommodating a wafer 600 such as a semiconductor substrate, a high-frequency power supply 444 for supplying high-frequency power to the plasma generation chamber 430 (particularly the resonance coil 432), and a frequency matcher 446 for controlling the oscillation frequency of the high-frequency power supply 444. For example, the plasma generation chamber 430 is disposed above a horizontal base plate 448 as a gantry, and the processing chamber 445 is disposed below the base plate 448. Also, the resonance coil 432 and the outer shield 452 constitute a spiral resonator.

[0024] The plasma generation chamber 430 is configured to be depressurized and supplied with a reaction gas for plasma, and is composed of a reaction vessel 431, a resonance coil 432 wound around the outer periphery of the reaction vessel, and an outer shield 452 disposed on the outer periphery of the resonance coil 432 and electrically grounded.

[0025] The reaction vessel 431 is a so-called chamber formed in a cylindrical shape from high-purity quartz glass or ceramics. The reaction vessel 431 is arranged so that its axis is vertical, and the upper and lower ends are hermetically sealed by a top plate 454 and a processing chamber 445 provided in a direction different from that of the top plate 454. The top plate 454 is supported by the flange 431b of the reaction vessel 431 and the upper end of the outer shield 452.

[0026] The top plate 454 has a lid portion 454a that closes one end of the reaction vessel 431 and a support portion 454b that supports the lid portion 454a. The lid portion 454a is a radially inner surface starting from the portion in contact with the tip portion 431a, and the support portion 454b is the portion supported by the flange 431b and the outer shield 452. A gas inlet 433 is provided substantially at the center of the lid portion 454a. An O-ring 453 is provided between the outer periphery of the tip portion 431a, the flange 431b, and the support portion 454b to configure the plasma generation chamber 430 to be airtight.

[0027] On the bottom surface of the processing chamber 445 below the reaction vessel 431, a susceptor 459 supported by a plurality (for example, four) of support columns 461 is provided. The susceptor 459 is equipped with a susceptor table 411 and a heater 463 as a substrate heating unit for heating the wafer on the susceptor. An exhaust plate 465 is disposed below the susceptor 459. The exhaust plate 465 is supported by a bottom plate 469 via a guide shaft 467, and the bottom plate 469 is hermetically provided on the lower surface of the processing chamber 445. A lift plate 471 is provided so as to be movable up and down using the guide shaft 467 as a guide. The lift plate 471 supports at least three lifter pins 413.

[0028] As shown in FIG. 3, the lifter pin 413 penetrates the susceptor table 411 of the susceptor 459. At the top of the lifter pin 413, a support portion 414 for supporting the wafer 600 is provided. The support portion 414 extends in the central direction of the susceptor 459. By raising and lowering the lifter pin 413, the wafer 600 can be placed on the susceptor table 411 or lifted from the susceptor table 411. Via the bottom plate 469, a lifting shaft 473 of a lifting drive unit (not shown) is connected to the lifting plate 471. By the lifting drive unit raising and lowering the lifting shaft 473, the support portion 414 is raised and lowered via the lifting plate 471 and the lifter pin 413. In addition, in FIG. 3, the lifter pin 413 with the support portion 414 attached is shown.

[0029] A baffle ring 458 is provided between the susceptor 459 and the exhaust plate 465. The baffle ring 458, the susceptor 459, and the exhaust plate 465 form a first exhaust chamber 474. The cylindrical baffle ring 458 is provided with a large number of uniformly distributed ventilation holes. Therefore, the first exhaust chamber 474 is partitioned from the processing space of the processing chamber 445. Also, it communicates with the processing space through the ventilation holes. Note that the processing space refers to the space for processing the substrate.

[0030] An exhaust communication hole 475 is provided in the exhaust plate 465. The first exhaust chamber 474 and the second exhaust chamber 476 are communicated by the exhaust communication hole 475. An exhaust pipe 480 is communicated with the second exhaust chamber 476, and a pressure regulating valve 479 and an exhaust pump 481 are provided in the exhaust pipe 480 from upstream. The gas exhaust portion is composed of the exhaust pipe 480, the pressure regulating valve 479, and the exhaust pump 481. The gas exhaust portion is connected to the processing chamber 445 via the second exhaust chamber 476.

[0031] On the top plate 454 at the upper part of the reaction vessel 431, a gas supply pipe 455 extending from the gas supply unit 482 and for supplying a reaction gas for required plasma is attached to the gas inlet 433. The gas inlet 433 is conical, and its diameter becomes larger as it gets closer to the processing chamber. The gas supply unit 482 (gas supply section) has, in order from the upstream side, a gas source 483, a mass flow controller 477 which is a flow rate control section, and an on-off valve 478. The gas supply unit 482 controls the supply amount of the gas by controlling the mass flow controller 477 and the on-off valve 478.

[0032] Also, the pressure in the processing chamber 445 is adjusted by adjusting the supply amount and the exhaust amount by the mass flow controller 477 and the pressure adjustment valve 479.

[0033] Fig. 4(a) shows the periphery of the baffle plate 460 according to a preferred embodiment of the present invention. Fig. 4(b) shows the periphery of the baffle plate 460 according to a comparative example.

[0034] The baffle plate 460 according to a preferred embodiment of the present invention is composed of, as shown in Fig. 4(a), for example, a first baffle plate 460a made of quartz and a second baffle plate 460b. The first baffle plate 460a is provided inside the reaction vessel 431, between the upper end of the resonance coil 432 and the gas inlet 433. Also, the second baffle plate 460b is provided between the first baffle plate 460a and the upper end of the resonance coil 432. That is, the first baffle plate 460a and the second baffle plate 460b are provided so as to overlap with a space therebetween between the upper end of the resonance coil 432 and the gas inlet 433. Also, the first baffle plate 460a and the second baffle plate 460b are provided between the susceptor table 411 and the gas inlet 433.

[0035] Further, the first baffle plate 460a and the second baffle plate 460b have substantially the same shape and are plate-shaped without holes. Also, they are shaped along the inner circumference of the reaction vessel 431. That is, if the inner circumference of the reaction vessel 431 is circular, the ends of the respective baffle plates are also circular. In other words, the baffle plates are disk-shaped along the inner circumference of the reaction vessel 431.

[0036] With such a configuration, a gas flow path flowing between the top plate 454 and the first baffle plate 460a and a gas flow path flowing between the reaction vessel 431 and the end of the baffle plate along the inner circumference of the reaction vessel 431 are formed. Since the gas supplied from the gas inlet 433 is supplied via each gas flow path, the gas supplied to the center of the reaction vessel 431 does not concentrate. That is, since the gas is supplied via the first baffle plate 460a and the second baffle plate 460b, as shown by the dashed arrow in Fig. 4(a), a gas flow is generated, and the gas will fall substantially vertically near the upper end of the resonance coil 432 (A-A line in Fig. 4(a)). Therefore, there is no gas loss.

[0037] On the other hand, as shown in Fig. 4(b), the baffle plate 460 according to the comparative example is composed of a single baffle plate 460. In the baffle plate 460 according to the comparative example, as shown by the dashed arrow in Fig. 4(b), a gas flow path is formed obliquely from the gas inlet 433 toward the outer circumference of the baffle plate 460, and the gas is diffused near the upper end of the resonance coil 432 (A-A line in Fig. 4(b)). That is, since the gas is diffused into a region with weak electrolytic strength, it will lead to weak plasma generation.

[0038] Here, in the case of an ICP type plasma generation device, it is known that the electric field for generating plasma is stronger the closer it is to the resonance coil 432. Therefore, by concentrating the gas in a place where the electric field is strong, that is, a place close to the resonance coil 432, the plasma generation efficiency can be increased. Also, in such a place, there is high energy, and a plasma with a long lifespan is generated. That is, by providing at least two baffle plates 460a and 460b, the gas is caused to flow along the inner wall of the reaction vessel 431 close to the resonance coil as shown by the arrow, and by concentrating the gas in a place where the electric field is strong, that is, a place close to the resonance coil 432, the plasma generation efficiency can be increased. Also, in such a place, plasma with high energy and a long lifespan is generated.

[0039] Next, the mounting structure of the baffle plates 460a and 460b will be described with reference to FIG. 5. FIG. 5 is an enlarged view of the baffle plates 460a and 460b and the top plate 454, and is a diagram for explaining the mounting structure of the baffle plates 460a and 460b. First, the fixing mechanism will be described with reference to FIG. 5(a). Insert the bolt 491 inserted into the top plate 454 successively into the first collar 492 with a hole in the center, the fixing hole provided in the first baffle plate 460a, the second collar 493 with a hole in the center, and the fixing hole provided in the second baffle plate 460b, and fix with the fixing bolt 494. The first collar 492 is made of metal (for example, an aluminum alloy), and the top plate 454 and the collar 492 are configured to be grounded. The fixing mechanism is provided evenly at least at three locations in the circumferential direction of the baffle plate 460.

[0040] Subsequently, the positional relationship among the baffle plates 460a and 460b, the top plate 454, and the reaction vessel 431 will be described with reference to FIG. 5(b). As shown in FIG. 5(b), the distance between the lid portion 454a of the top plate 454 and the surface of the first baffle plate 460a facing the lid portion 454a is defined as GAP(a). GAP(a) is set to be from 1 mm to 5 mm, more desirably from 2 mm to 4 mm. The distance between the opposing surfaces of the first baffle plate 460a and the second baffle plate 460b is defined as GAP(b). GAP(b) is from 30 mm to 50 mm. The distance between the diameter of the baffle plate 460 and the reaction vessel is set to be from 0.1 to 10 mm. Specifically, the baffle plate has a diameter of 269 mm, which is smaller than the diameter of the substrate, and the inner circumference of the reaction vessel 431 is 275 mm.

[0041] The distance between the first baffle plate 460a and the gas inlet 433 is set to be a distance such that abnormal discharge does not occur between the first baffle plate 460a and the lid part 454a, and particularly, it is set to be a distance such that abnormal discharge does not occur in the vicinity of the gas inlet 433.

[0042] The abnormal discharge mentioned here refers to, for example, the following phenomena. When Ar gas, which facilitates discharge, is added to the processing gas, due to the influence of the electric field generated from the resonance coil 432, discharge occurs between the first baffle plate 460a and the lid part 454a. In particular, in the vicinity of the gas introduction hole 433, since it is a region where the processing gas tends to stay, discharge is likely to occur. The cause of this discharge is presumed to be due to the addition of Ar gas. Since Ar gas has the property of facilitating discharge, it is considered that even if the electric field generated from the resonance coil 432 is a weak electric field, the processing gas will discharge.

[0043] When discharge occurs, the following problems are considered to occur. One is that the plasma generated in the vicinity of the gas inlet 433 enters the gas supply pipe 455, resulting in etching of the gas supply pipe 455. By etching, there is a possibility of generating particles. In particular, when the gas supply pipe 455 is formed of metal, it is considered that the processing chamber 445 will be contaminated with metal, which will have an adverse effect on substrate processing. Second, the plasma generated between the first baffle plate 460a and the lid part 454a may come into contact with the O-ring 431a, which may accelerate the deterioration of the O-ring 431a.

[0044] In order to suppress the above-mentioned discharge, as a result of intensive research by the inventors, it has been found that by increasing the flow rate of the processing gas, the discharge can be suppressed. Specifically, the distance between the first baffle plate 460a and the lid portion 454a is narrowed. By adopting such a structure, the pressure between the first baffle plate 460a and the lid portion 454a can be increased, and as a result, the flow rate of the gas can be increased.

[0045] Subsequently, the positional relationship between the second baffle plate 460b and the resonance coil 432 will be described. The second baffle plate 460b is configured such that the surface facing the susceptor table 411 within the second baffle plate 460b is positioned at a height above the upper end (A - A line) of the resonance coil 432. In other words, it is configured to be positioned between the upper end of the resonance coil 432 and the first baffle plate 460a. By adopting such a configuration, since the gas flows near the resonance coil 432, efficient plasma generation becomes possible. Furthermore, it is possible to prevent the diffusion and deactivation of the plasma and supply as many active reaction species as possible to the downstream wafer. By bringing the second baffle plate 460b closer to the upper end of the resonance coil 432, it becomes possible to reduce the volume of the plasma generation region and increase the plasma density per unit volume. Therefore, it becomes possible to transport as many active reaction species as possible downstream. As described above, the baffle structure is configured.

[0046] Here, the flow rate of the gas will be described with reference to FIG. 6. FIG. 6 is a flow rate distribution diagram. FIG. 6(a) shows an example using the baffle plate 460 according to the comparative example, where a single baffle plate is set. (b) shows an example using the baffle plate 460 according to the present embodiment, where two baffle plates 460a and 460b are set. In the example using a single baffle plate 460 of the comparative example, it can be seen that the flow rate is low near the gas inlet 433 and high between the baffle plate 460 and the lid portion 454a. Furthermore, it can be seen that the gas is stagnating in a spiral shape. From this, it is speculated that abnormal discharge occurs between the baffle plate 460 and the lid portion 454a. On the other hand, in the example where two baffle plates 460 according to the present embodiment are used, it can be seen that discharge can be suppressed because gas does not accumulate between the first baffle plate 460a and the lid portion 454a.

[0047] Fig. 7 shows a diagram illustrating the relationship between RF power, the baffle plate 460, and discharge. The vertical axis represents the RF power applied to the resonance coil 432. The normal discharge limit power was measured in the state without the baffle plate 460, the state with one baffle plate 460, and the state with two baffle plates 460, respectively. The normal discharge limit power is the power at which abnormal discharge does not occur. The process conditions at this time are as follows. Atmosphere: PR-GAS (CH4: 10%, Ar: 90%) Flow rate: 0.2 to 3.0 slm Pressure: 50 to 250 mTorr

[0048] As can also be seen from this figure, in the state without the baffle plate 460, normal discharge is possible up to 1000 W. Also, in the state with one baffle plate 460, normal discharge is possible up to 3000 W. Further, in the state with two baffle plates 460, normal discharge is possible up to 4900 W.

[0049] In the case of an ICP type plasma generation device, the higher the RF power, the more efficiently the plasma state can be achieved. Therefore, in the range where abnormal discharge does not occur, a state with a high RF power is desirable. Accordingly, the state with two baffle plates is more desirable than the state without a baffle plate or the state with one baffle plate.

[0050] The resonance coil 432 is wound such that its diameter, winding pitch, and number of turns are set to resonate in a certain wavelength mode in order to form a standing wave of a predetermined wavelength. That is, the electrical length of the resonance coil 432 is set to an integer multiple (1 times, 2 times,...), a half wavelength, or a 1 / 4 wavelength corresponding to one wavelength at the predetermined frequency of the power supplied from the high-frequency power supply 444. For example, the length of one wavelength is approximately 22 meters at 13.56 MHz, approximately 11 meters at 27.12 MHz, and approximately 5.5 meters at 54.24 MHz. The resonance coil 432 is formed in a flat plate shape from an insulating material and is supported by a plurality of supports vertically erected on the upper end surface of the base plate 448.

[0051] Both ends of the resonance coil 432 are electrically grounded, but at least one end of the resonance coil 432 is grounded via a movable tap 462 in order to finely adjust the electrical length of the resonance coil during the initial installation of the device or when the processing conditions are changed. Reference numeral 464 in FIG. 3 indicates the other fixed ground. Further, in order to finely adjust the impedance of the resonance coil 432 during the initial installation of the device or when the processing conditions are changed, a power supply unit is configured by a movable tap 466 between the grounded ends of the resonance coil 432.

[0052] That is, the resonance coil 432 has grounded portions at both ends and a power supply unit that is supplied with power from the high-frequency power supply 444 between the respective ground portions. Moreover, at least one of the ground portions is a variable ground portion whose position can be adjusted, and the power supply unit is a variable power supply unit whose position can be adjusted. When the resonance coil 432 is provided with a variable ground portion and a variable power supply unit, as will be described later, it is possible to adjust more simply when adjusting the resonance frequency and the load impedance of the plasma generation chamber 430.

[0053] The outer shield 452 is provided to shield the leakage of electromagnetic waves to the outside of the resonance coil 432 and to form a capacitance component necessary for constituting the resonance circuit between the resonance coil 432. The outer shield 452 is generally formed in a cylindrical shape using a conductive material such as an aluminum alloy, copper, or a copper alloy. The outer shield 452 is disposed at a distance of, for example, about 5 to 150 mm from the outer periphery of the resonance coil 432.

[0054] An RF sensor 468 is installed on the output side of the high-frequency power supply 444 to monitor traveling waves, reflected waves, etc. The reflected wave power monitored by the RF sensor 468 is input to the frequency matcher 446. The frequency matcher 446 controls the frequency so that the reflected wave is minimized.

[0055] The controller 470 corresponds to the controller 500 in FIG. 1 and controls not only the high-frequency power supply 444 but also the entire ashing apparatus 10. A display 472, which is a display unit, is connected to the controller 470. The display 472 displays data detected by various detection units provided in the ashing apparatus 10, such as the monitoring result of the reflected wave by the RF sensor 468.

[0056] For example, during the ashing process or when the plasma is generated before the ashing process, when the processing conditions change during the plasma processing (such as increasing the gas species), the gas flow rate, gas mixing ratio, and pressure may change, and the load impedance of the high-frequency power supply 444 may also change. Even in such a case, since the ashing apparatus 10 has a frequency matcher 446, it can immediately follow the changes in the gas flow rate, gas mixing ratio, and pressure and match the transmission frequency of the high-frequency power supply 444.

[0057] Specifically, the following operations are performed. During plasma generation, it converges to the resonance frequency of the resonance coil 432. At this time, the RF sensor 468 monitors the reflected wave from the resonance coil 432 and transmits the level of the monitored reflected wave to the frequency matcher 446. The frequency matcher 446 adjusts the transmission frequency of the high-frequency power supply 444 so that the reflected wave power is minimized.

[0058] Subsequently, a semiconductor manufacturing method that employs the substrate processing method (photoresist removal method) of the present invention as one step will be described with reference to FIG. 8. FIG. 8 illustrates a process of manufacturing a semiconductor device (semiconductor device) using the substrate processing method of the present invention and an ashing apparatus 10 or the like.

[0059] FIG. 8 shows a process of processing a substrate (wafer 600) using the ashing apparatus 10, and a substrate processing method according to an embodiment of the present invention is shown. In the method for processing a substrate according to the present invention, as shown in FIG. 8, a series of steps including at least a loading step S100 of loading the substrate into a processing chamber, a heating step S200 of heating the substrate, a processing step S300 of supplying a reaction gas and processing the substrate, and an unloading step S400 of unloading the substrate from the processing chamber are performed to process the substrate.

[0060] In the loading step S100, the wafer 600 coated with resist is loaded into the processing chamber 445. In the heating step S200, the wafer 600 loaded into the processing chamber 445 in the loading step S100 is heated. In the processing step S300, a reaction gas containing at least a hydrogen component and an argon component is supplied into the processing chamber 445. For example, PR-GAS (a mixed gas of CH4 and argon) is supplied. Further, the wafer 600 is processed with the reaction gas supplied to the processing chamber in a plasma state. In the unloading step S400, the processed wafer 600 is unloaded from the processing chamber 445.

[0061] Hereinafter, an example of substrate processing using the ashing apparatus 10 will be described more specifically. The operations of each part of the ashing apparatus 10 are controlled by the controller 470.

[0062] <Loading Step S100> In the loading step S100, the finger 321 of the vacuum arm robot 320 conveys the wafer 600 to the processing chamber 445. That is, the finger 321 carrying the wafer 600 enters the processing chamber 445, and the finger 321 places the wafer 600 on the lifted lifter pin 413. The tip of the lifter pin 413 is maintained in a state floating from the susceptor table 411. The wafer 600 is transferred onto the lifter pin 413, that is, in a state floating from the susceptor table 411. At this time, the wafer 600 is held at, for example, room temperature.

[0063] 〔Heating Step S200〕 In the heating step S200, the wafer 600 is held in a floating state from the susceptor table 411 and heated by the heater 463 of the susceptor table 411. The wafer temperature is controlled by the distance between the susceptor table 411 and the wafer 600. In this heating step S200, the temperature of the wafer 600 is set to be 200°C or higher and 400°C or lower.

[0064] 〔Processing step S300〕 In the processing step S300 of supplying the reaction gas, the reaction gas (ashing gas) is supplied from the reaction vessel 431 to the gas inlet 433 and then to the plasma generation chamber 430. The supplied reaction gas is a reaction gas containing at least a hydrogen component and an argon component.

[0065] After the processing chamber 445 reaches a predetermined condition, the supplied reaction gas is turned into a plasma state by the resonance coil 432. That is, after the reaction gas is supplied in the step of supplying the reaction gas, the high-frequency power supply 444 supplies power to the resonance coil 432, accelerates free electrons by the induced magnetic field excited inside the resonance coil 432, and collides with gas molecules to excite the gas molecules to generate plasma. Then, substrate processing is performed by this reaction gas in the plasma state, and the resist is removed.

[0066] In this embodiment, as the reaction gas used in the processing step S300, a reaction gas containing at least a hydrogen component and an argon component is supplied. Here, Ar gas is used, but more specifically, a gas obtained by adding a dilution gas composed of at least one gas selected from the group consisting of N2 gas and He gas to hydrogen can be used.

[0067] 〔Unloading step S400〕 In the unloading step S400, after the ashing treatment step is completed, the lifter pin 413 rises. The finger 321 of the vacuum arm robot 320 picks up the processed wafer 600 on the lifter pin 413 and transports it to the load lock chamber part 310, or the load lock chamber 210 or 220 via the transfer chamber part 310.

[0068] In this embodiment, the ashing process has been described as an example, but the present invention is not limited thereto, and it can be implemented by a process using plasma, such as an etching process, a film modification process, or a film formation process.

[0069] In addition, in this embodiment, an example in which two baffle plates are used has been described, but the present invention is not limited thereto, and a plurality of baffle plates may be used between the upper end of the coil and the gas inlet.

[0070] As described above, according to this embodiment, the gas can flow along the inner wall of the reaction vessel 431, and the gas can be supplied to a region where the electric field is strong, so that the plasma generation efficiency can be increased. In addition, plasma with high energy and a long lifespan is generated. Therefore, processing at a high ashing rate becomes possible, and as a result, the throughput of the entire apparatus can be increased.

[0071] The present invention is as described in the claims, and further includes the following appended matters.

[0072] 〔Appended Note 1〕 A substrate processing apparatus including: a reaction vessel having a coil provided on the outer periphery and configured in a cylindrical shape; a lid portion provided at an end of the reaction vessel; a gas inlet provided in the lid portion; a first plate provided between the gas inlet and the upper end of the coil; a second plate provided between the first plate and the upper end of the coil; a substrate processing chamber provided inside the reaction vessel in a direction different from the lid portion; and a gas exhaust portion connected to the substrate processing chamber.

[0073] 〔Appended Note 2〕 The substrate processing apparatus according to Appended Note 1, having an O-ring on the outer periphery of the tip of the reaction vessel.

[0074] 〔Appended Note 3〕 A method for manufacturing a semiconductor device using a substrate processing apparatus, the apparatus comprising: a reaction vessel having a coil provided on its outer periphery and being cylindrical in shape; a lid provided at an end of the reaction vessel; a gas inlet provided on the lid; a first plate provided between the gas inlet and the upper end of the coil; a second plate provided between the first plate and the upper end of the coil; a substrate processing chamber provided inside the reaction vessel in a direction different from that of the lid; and a gas exhaust unit connected to the substrate processing chamber. The method includes the steps of: guiding the gas introduced from the gas inlet to the vicinity of the coil through the first and second plates; converting the gas into a plasma state by the coil and processing the substrate placed in the substrate processing chamber; and exhausting the gas by the gas exhaust unit.

[0075] [Appendix 4] A baffle structure for use in a substrate processing apparatus, the apparatus comprising: a reaction vessel having a coil provided on its outer periphery and being cylindrical in shape; a lid provided at an end of the reaction vessel; a gas inlet provided on the lid; a substrate processing chamber provided inside the reaction vessel in a direction different from that of the lid; and a gas exhaust unit connected to the substrate processing chamber. The baffle structure includes stacking and arranging a first plate and a second plate between the gas inlet and the upper end of the coil.

[0076] [Appendix 5] A baffle structure for use in a substrate processing apparatus, the apparatus comprising: a reaction vessel having a coil provided on its outer periphery and being cylindrical in shape; a lid provided at an end of the reaction vessel; a gas inlet provided on the lid; a substrate processing chamber provided inside the reaction vessel in a direction different from that of the lid; and a gas exhaust unit connected to the substrate processing chamber. The baffle structure forms a baffle structure by overlapping a first plate and a second plate with a space therebetween, and is configured such that the height of the baffle structure is lower than the distance between the gas inlet and the upper end of the coil.

Explanation of Reference Numerals

[0077] 10…Asher 100…EFEM 110, 120…FOUP 130…Atmospheric Robot 200…Load lock chamber section 210, 220…Buffer unit 211, 221…Boat 212, 222…Index assembly 250, 260…Load lock chamber 300…Transfer chamber section 310…Transfer chamber 311, 312, 313, 314…Gate valve 320…Vacuum arm robot unit 321…Finger 325…θ axis 326…Y axis 400…Process chamber section 410, 420…Plasma processing unit 411, 421…Susceptor table 412, 422…Z axis 413, 423…Lifter pin 430, 440…Plasma generation chamber 431, 441…Reaction vessel 432, 442…Resonance coil 433, 443…Gas inlet 445…Processing chamber 444…High-frequency power supply 446…Frequency matcher 448…Base plate 452…Outer shield 453…O-ring 454…Top plate 454a…Cover part 455…Gas supply pipe 458…Baffle ring 460…Baffle plate 462…Movable tap 463…Heater 464…Fixed ground 466…Movable tap 468…RF sensor 470, 500…Controller 472…Display (display device) 480…Exhaust pipe 482… Gas supply unit 600… Wafer

Claims

1. A reaction vessel, a coil provided on the outer periphery of the side wall of the reaction vessel, a gas inlet provided on the upper end face of the inner side of the reaction vessel, a baffle portion provided between the gas inlet and the upper end of the coil inside the reaction vessel so as to have a gap with the upper end face of the vessel, a fixing mechanism in which a section corresponding to the gap is constituted by a metal collar and the baffle portion is fixed to the upper end face of the vessel, A substrate processing apparatus having the same.

2. The substrate processing apparatus according to claim 1, wherein the baffle portion is made of quartz.

3. The substrate processing apparatus according to claim 1 or 2, wherein the fixing mechanism is provided inside the outer edge of the baffle portion.

4. The substrate processing apparatus according to any one of claims 1 to 3, wherein the collar is configured such that the diameter of the section corresponding to the gap is larger than the diameter of the section inserted into the hole provided in the baffle portion.

5. The substrate processing apparatus according to any one of claims 1 to 4, further including bolts inserted into the upper end face of the vessel and penetrating the collar.

6. A reaction vessel, a coil provided on the outer periphery of the side wall of the reaction vessel, a gas inlet provided on the upper end face of the inner side of the reaction vessel, a baffle portion provided between the gas inlet and the upper end of the coil inside the reaction vessel so as to have a gap with the upper end face of the vessel, a fixing mechanism in which a section corresponding to the gap is constituted by a metal collar and the baffle portion is fixed to the upper end face of the vessel, A step of introducing gas from the gas inlet of the substrate processing apparatus having the same into the reaction vessel, a step of generating plasma of the gas in the reaction vessel by supplying high-frequency power to the coil, a step of processing a substrate using the plasma generated in the reaction vessel, A substrate processing method having the same.

7. A reaction vessel, a coil provided on the outer periphery of the side wall of the reaction vessel, a gas inlet provided on the upper end face of the inner side of the reaction vessel, a baffle portion provided between the gas inlet and the upper end of the coil inside the reaction vessel so as to have a gap with the upper end face of the vessel, a fixing mechanism in which a section corresponding to the gap is constituted by a metal collar and the baffle portion is fixed to the upper end face of the vessel, A step of introducing gas from the gas inlet of the substrate processing apparatus having the same into the reaction vessel, A step of generating plasma of the gas in the reaction vessel by supplying high-frequency power to the coil; A step of processing a substrate using the plasma generated in the reaction vessel; A method for manufacturing a semiconductor device having the above steps.

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