JP2001093871A - Plasma arc cutting apparatus, manufacturing process and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems that more than half of currently employed semiconductor processes are performed by decompressed devices, that a cleaning apparatus and aligner can be used only under atmospheric pressure, and that the interface between the devices operated under atmospheric pressure and those operated under reduced pressure cannot be constituted smoothly which becomes a bottleneck for efficient processes. SOLUTION: Plasma containing high-density radicals is formed linearly by using microwaves and damage-free and high-speed film formation, etching and so forth are performed so as to realize continuous machining of wafers or the like. Load locking becomes unnecessary by operating devices under substantially atmospheric pressure and isolating process spaces or the like by a gas flow. Since processes such as film formation, CVD, etching, planarization, cleaning and so forth can be conducted directly by only switching the gas, majority of processes can be performed under atmospheric pressure, thus enabling efficient processes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus and a device manufacturing process. More specifically,
With regard to processes such as etching, planarization, cleaning, and hydrogen termination, it is particularly suitable for continuous processing equipment using linear ultra-high-density plasma excited by microwaves or lasers, and manufacturing processes for devices using this equipment. It is suitable.

[0002]

2. Description of the Related Art In recent years, semiconductor devices have been miniaturized.
Accordingly, flattening in the process is essential. Currently, this planarization process is performed by CMP (Chemic).
alMechanical Polishing) is often used, but there are many problems such as securing uniformity, regenerating used abrasive grains, and treating highly concentrated chemicals. In semiconductor processes where particle control is important,
It is also necessary to isolate only the CMP in another area.

In the current process of exposing the wafer surface to the atmosphere, it is important to control the natural oxide film on the surface. In particular, highly doped Si surfaces and metal surfaces are very easily oxidized. This natural oxide film causes various device performance deteriorations such as deterioration of oxide film characteristics during gate oxidation, increase in contact resistance, and increase in wiring resistance.

[0004] The roughness of the Si surface is one of the factors directly affecting the performance fluctuation of the device. It is difficult to obtain a flat surface in the atomic order, and sacrificial oxidation must be repeatedly performed in addition to CMP. Therefore,
A heat treatment of about 800 ° C. or more and a long time is always required. Although a planarization process using hydrogen has been put to practical use, it also has a similar problem due to a long-time high-temperature process exceeding 900 ° C.

At present, the cleaning process is performed by using a wet process. In semiconductor manufacturing, contaminants generated are often extremely small, but a large amount of ultrapure water and chemicals are consumed to remove them.

[0006]

[0007] Even if a plasma apparatus currently used is used, flattening, cleaning, natural oxide film removal,
It is possible to perform steps such as hydrogen termination. However, generally used plasma has an operating pressure of several mTorr to several Torr, and a plasma density of only about 10 ¹² 1 / cm ³ can be obtained at a high plasma density. It is about several nm / min to several μm / min.

Further, since many plasma devices operate at low pressure, they must be evacuated and opened to the atmosphere, and a load lock mechanism is also required. Therefore, each process must be performed sequentially while moving in the isolated space.

On the other hand, continuous processing is possible by forming a linear plasma and performing the process while continuously moving the wafer. For example, when a plate of 300 mm × 300 mm is continuously processed in one minute. Then, the processing of 1 mm width must be completed in 0.2 sec (that is, if the processing of 1 μm depth is performed, the processing speed is 300 μm / min), which is several orders of magnitude higher than the conventional plasma apparatus. Processing speed is required.

On the other hand, a high-pressure plasma apparatus includes a parallel plate type continuous processing apparatus using a high frequency and a diffusion type processing apparatus using a microwave. The electrical design is difficult, the peripheral circuits are large, and the plasma density is relatively low. Conventional microwave excitation equipment can obtain high-density plasma at the excited part, but it needs a diffusion distance necessary to make it uniform, so the equipment becomes larger, and Ions and radicals also reach the plate after repeated frequent collisions at atmospheric pressure, so that the density of ions and radicals at sites used for actual processing is significantly reduced.

In order to increase the processing speed by several orders of magnitude in order to realize such a continuous process, it is indispensable to form a high-density plasma linearly near the plate surface.

[Means for Solving the Problems]

The plasma processing apparatus of the present invention forms a linear plasma using electromagnetic waves, and continuously moves the relative positions of the workpiece and the plasma while keeping the workpiece surface horizontal to the linear plasma. While processing the surface of the workpiece.

In one embodiment of the plasma processing apparatus according to the present invention, the electromagnetic wave is a microwave.

In one embodiment of the present invention, the electromagnetic wave is a laser.

As one mode of the plasma processing apparatus of the present invention, the operating pressure is 0.1 mTorr or more.

In one embodiment of the plasma processing apparatus according to the present invention, the operating pressure is substantially atmospheric pressure.

As one mode of the plasma processing apparatus of the present invention, a film is formed directly on the surface of a workpiece by plasma using a mixed gas of at least one of oxygen, nitrogen, ammonia, hydrogen and fluorine and a rare gas.

As one mode of the plasma processing apparatus of the present invention, a CVD film is formed on the surface of a workpiece by plasma using a source gas and a mixed gas of at least one of hydrogen, oxygen, and nitrogen and a rare gas.

As one mode of the plasma processing apparatus of the present invention, the surface of a workpiece is etched by plasma using a mixed gas of a raw material gas and at least one of hydrogen and oxygen and a diluent gas.

As one mode of the plasma processing apparatus of the present invention, at least one of cleaning of a workpiece surface and flattening of a metal surface is performed by plasma using a mixed gas of a raw material gas and at least one of hydrogen and oxygen and a diluent gas. Do one.

As one mode of the plasma processing apparatus of the present invention, at least one of planarization of a workpiece surface, removal of a natural oxide film, and hydrogen termination is performed by plasma using a mixed gas of a diluent gas and hydrogen.

As one mode of the plasma processing apparatus of the present invention, the processing apparatus is cleaned by plasma using a mixed gas of a raw material gas and at least one of hydrogen and oxygen and a diluent gas.

In one embodiment of the plasma processing apparatus of the present invention, the dilution gas contains at least one of He, Ne, Ar, Kr and Xe.

In one embodiment of the plasma processing apparatus of the present invention, the source gas for CVD is SixHy, SiHxCly.
And at least one of organic metal gases.

In one embodiment of the plasma processing apparatus of the present invention, the source gas for etching and chamber cleaning contains at least one of NF ₃ , fluorocarbon, SF ₆ and CO _x .

As one mode of the plasma processing apparatus of the present invention, the source gas in etching, cleaning and metal flattening contains a halogen element.

In one embodiment of the plasma processing apparatus of the present invention, the halogen gas used in etching, cleaning and metal flattening is chlorine and bromine.

In one embodiment of the plasma processing apparatus of the present invention, the source gas used for planarization contains at least one of Si _{x Hy} and SiH _x Cl _y .

As one mode of the plasma processing apparatus of the present invention, the effective process speed is controlled by changing the radiation surface width of the electromagnetic wave.

As one mode of the plasma processing apparatus of the present invention, a hermetic seal is performed by forming a viscous flow in a gap between the workpiece and the apparatus.

As one mode of the plasma processing apparatus of the present invention, the workpiece is fixed to a stage on which the workpiece moves integrally.

As one mode of the plasma processing apparatus according to the present invention, microwaves are supplied in substantially the same phase over the entire radiation surface to the plasma.

As one form of the plasma processing apparatus of the present invention, a protective film having high corrosion resistance is formed on the surface of a member of a workpiece transfer device.

As one mode of the plasma processing apparatus of the present invention, at least two or more of the plasma processing apparatuses according to claims 6 to 11 are connected, and a plurality of processes are continuously processed.

As an embodiment of the plasma processing apparatus of the present invention, a water removing mechanism is connected.

As one mode of the plasma processing apparatus of the present invention, a gas contact portion in the apparatus is heated from 50 ° C. to 250 ° C.

As one mode of the plasma processing apparatus of the present invention, the shape of the workpiece is a plate.

In one embodiment of the plasma processing apparatus according to the present invention, at least a part of the workpiece is a semiconductor.

In one embodiment of the plasma processing apparatus of the present invention, at least a part of the workpiece is silicon.

In one embodiment of the plasma processing apparatus according to the present invention, at least a part of the workpiece is a glass substrate.

In one embodiment of the plasma processing apparatus according to the present invention, at least a part of the workpiece is a resin substrate.

In the plasma processing apparatus using plasma excited by electromagnetic waves according to the present invention, a gas laminar flow comprising at least two layers is formed in a plasma forming section, and a gas type to be supplied to each gas flow is selected. And control the dissociation and excitation of the source gas.

The manufacturing process of the device according to the present invention is described in claim 6.
, 23 to 25 and 28, at least a part is processed.

The device according to the present invention is characterized in that:
At least a part is processed by the plasma processing apparatus described in 23 to 25 and 28.

BEST MODE FOR CARRYING OUT THE INVENTION

For example, at atmospheric pressure, the density of gas molecules is 1
It is about ²⁰ molecules / cm ³ . Assuming that the ratio of gas molecules to be ionized is 1/10000, the plasma density is 1
Since about ¹⁶ ions / cm ³ and the ratio of radicals are about several percent, high-density plasma with radical density of about 10 ¹⁸ radicals / cm ³ can be formed. That is, by using this ultra-high density plasma,
The processing speed can be improved by two to three digits as compared with the conventional plasma process. For example, even when processing of several μm is required, the process is completed in a processing time of about several hundred msec. For example, it is possible to process a plate having an area equivalent to a 300 mm wafer in several seconds to several tens of seconds in one process.

When operated at a high pressure, it is possible to completely prevent external contamination and the backflow of reaction products by controlling the air flow around the plate, and it is necessary to completely seal the process space. Disappears. At that time, since the separation from the outside can be performed by airflow control (air curtain), the time for evacuation and opening to the atmosphere is reduced, and a load lock mechanism is not required. This makes it possible to process a plate by a flow operation (continuously processing a plurality of chambers adjacent to a transport path using a caterpillar, a belt, a roller, etc.), which was impossible at all. .

Further, since a continuous process can be continuously processed, by arranging a plurality of process devices adjacent to each other, the next process can be started before one process is completed, and the process time can be reduced. It becomes possible. In this case, it is necessary to make the processing speed in each step the same. For example, a processing speed that is slow can be dealt with by increasing the energy input to the plasma to increase the plasma density and by arranging a plurality of chambers for performing the same process in series. Furthermore, by making the line width of the plasma formation region in the plate advancing direction variable, the effective process time can be changed.
It is also possible to adjust the effective process speed without changing the process conditions.

The plasma used in the present invention is mainly excited by microwaves. The microwave is an electromagnetic wave having a frequency of several hundred MHz to several tens GHz. Since these discharges are electromagnetic wave excitation, it is possible to excite plasma even through an insulating film, for example, and to excite the plasma at a higher frequency to reduce the irradiation energy of ions from the plasma to several eV or less. Thus, contamination due to sputtering from a material constituting the chamber can be suppressed.
If a high frequency is used, if the excitation line width is changed, the impedance of the system changes, and a mechanism for actively changing the impedance inside the power supply circuit is required. However, in the case of microwaves, the line width can be changed only by changing the width of the slot, for example, and there is no need to change the power supply circuit configuration accordingly.

Embodiment 1

Hereinafter, an embodiment of the present invention will be described with reference to the drawings and the like.

FIG. 1 is a schematic cross-sectional view of the present apparatus in the plate advancing direction. The plasma excitation unit 103 is provided on the chamber wall 100
In addition, the gap between the transfer device 104 and the outside is shut off from the outside atmosphere. At this time, by setting the pressure of each part as P ₃ > P ₁ > P ₂ , the chamber wall 100 and the transfer device 10
In the gap of 4, it is possible to form a viscous flow,
Leakage of the process gas to the outside of the chamber can be prevented. In order to enhance the effect of preventing leakage, it is desirable that the flow between the chamber wall 100 and the transfer device 104 be laminar.

When the structure of each part of the device is determined, the conductance of each gap is uniquely determined.
If the pressure of ₁ · P ₂ · P ₃ is determined, the plasma generator 1
01 and the transfer device 104, that is, the flow rate to the plasma excitation unit, and the flow rate between the chamber wall 100 and the transfer device 104, that is, the leakage flow to the outside can be set. Therefore, this device can regulate the gas flow rate as long as it has a mechanism for regulating the pressure. Thus, if it is desired to realize a simpler device, only the pressure needs to be controlled, and a flow meter is not required. It goes without saying that any flow rate can be obtained by using a flow meter.

FIG. 2 is a schematic cross-sectional view taken along the line AA ′ of FIG. 102 indicates the plate on which the process takes place. If there is a concern that the plate may be slipped like a silicon wafer, for example, or if it is desired to improve the uniformity when performing heating or the like, place the plate on a stage larger than the plate, By being transported by the transport device 104,
The plate can be prevented from being damaged, and a highly uniform process can be performed.

When a non-square plate is used, the sealing characteristic between the chamber wall 100 and the transfer device 104 changes reflecting the plate shape, and a pressure fluctuation in the process space occurs. Therefore, the plate 102 and the transport device 1
It is desirable to adopt a structure in which the plate 102 is buried in the transfer device 104 so that the space between the process surface 04 and the chamber wall 100 is equal. When a circular silicon wafer or the like, which is widely used at present, is used, a groove having a radius substantially equal to that of the silicon wafer and having a depth substantially equal to the thickness of the silicon wafer is formed on the stage. By making the heights uniform, the uniformity of the process at the edge portion can be improved.

When using a stage and performing heating or the like, it is important to ensure uniformity of heat over the entire surface of the plate.
For this purpose, it is desirable to use a material having high thermal conductivity at least for a portion of the stage that is in contact with the wafer. As an insulator, AlN.Al ₂ O ₃ is desirable.

When using at high pressure, it is desirable to secure the adhesion by evacuating the back surface of the plate. At this time, even if the amount is small, the process or suction of the seal gas can prevent the moisture adsorbed on the back surface of the plate from diffusing into the process space.

When the pressure control as shown in FIG. 1 is performed, the process gas does not leak to the outside, but the gas in the external atmosphere is mixed into the process gas. is there. On the other hand, by adopting a structure as shown in FIG. 3 and setting the pressure so that the pressure satisfies P ₄ > P ₃ P ₄ > P ₁ > P ₂ , the gas introduction path 300
And the gas blown from 301 allows sealing. Since a part of the gas blown out from the gas introduction path 301 is directly supplied to the plasma 103, it is preferable to use the gas as a carrier gas for the process. On the other hand, the gas blown out from the gas introduction path 300 does not reach the plasma unit 103 particularly when the gas is supplied in a viscous flow, and therefore, for example, high-purity N ₂ or the like may be used regardless of the process.

The present apparatus can be operated at a pressure of 0.1 Torr or more at which high-density plasma can be formed by microwaves. However, when the pressure is low, the gas flow becomes viscous or molecular. Separation methods and the like are required.
However, when the thickness of the film to be formed is small, or in a line employing vacuum tunnel transfer or the like, it may be desirable to use the film at a low pressure operation.

(Linear Excitation Method Using Electromagnetic Wave) In order to form a linear plasma using microwaves, a structure as shown in FIG. 4 is formed, for example, inside 101 in FIG. This structure includes an H-plane slot antenna 400 and a uniformized line 40.
4. A slot array is formed between the H-plane slot antenna 400 and the equalizing line 402. The slot array is composed of slots 401 alternately arranged on the left and right of the waveguide center line 405 at a pitch of １ ／ of the guide wavelength. Microwaves with the same phase emitted from the slot array are supplied to the equalizing line 404. In this case, the long axis of the slot 401 is set parallel to the waveguide center line 405,
The slot 401 may be inclined with respect to the waveguide centerline 405.

The H-plane slot antenna 400 can be replaced with a structure capable of emitting microwaves having the same phase in a linear manner. Similar effects can be obtained with slot arrays formed in circular waveguides, coaxial waveguides, etc., as well as E-plane antennas. If the length of the linear plasma in the major axis direction is relatively short, a horn antenna or the like can be used. For feeding power to the H-plane slot antenna 400, a straight pipe connection is possible in addition to the T-branch. When other structures are adopted, the connection is made using a coaxial waveguide converter, a circular-rectangular waveguide converter, or the like. A system using traveling waves is also possible, but if power supply efficiency is taken into account, the terminals are short-circuited,
It is desirable to use a tuner or the like as a resonance system.

The equalizing line 402 is a parallel plate line (in practice, a center line) for forming a spatially uniform microwave wavefront using microwaves having the same phase emitted from the slot array. 405 direction). With this track, each slot 4
The microwaves discretely emitted from 01 are homogenized,
A wavefront having a more uniform intensity is formed in the direction of the center line 405. When such an effect is obtained, especially when a resonance system is designed, the height of the uniformizing line 404 in the vertical direction of the drawing is set to the guide wavelength of the uniforming line 402 (approximately uniform because of the flat rectangular waveguide). The height may be an integral multiple of a half wavelength of the free space wavelength in consideration of the dielectric constant inside the line 402. By doing so, the resonance condition in the longitudinal direction of the uniformized line 402 is satisfied, and efficient excitation can be performed.

The microwave uniformed by the equalizing line 402 is emitted from the slit 403 into plasma. By making the width of the slit 403 variable, the effective process speed can be changed.

When the pressure is high, the effect of plasma diffusion cannot be obtained, so that the shape of the formed plasma strongly correlates with the intensity of the microwave. Therefore, it is desirable to adopt a configuration that enables uniform discharge as shown in FIG.
On the other hand, when the operating pressure is low, the diffusion of the plasma can be expected, so that the same effect can be obtained without the uniformizing line. Also, in the case where a uniform wavefront can be formed independently as in the case of a horn antenna, the uniformized line may not be provided. To deflect the excitation width in case of horn antenna,
A slit may be formed on the front surface of the antenna.

If a discharge occurs in the path to the microwave emission surface in common with all plasma supply systems, the microwave is consumed in the discharge unit. In order to prevent discharge at unnecessary portions, a method of filling a path with a gas such as SF ₆ that is difficult to discharge, a method of filling by evacuation or pressurizing to maintain a pressure at which discharge is difficult, and a method of filling a dielectric are used. . In the case of filling the dielectric material, the loss is small due to the propagation path of the microwaves of SiO ₂ (thermal conductivity: up to 1.4).
[W / m · K]) · Al ₂ O ₃ (Thermal conductivity: 10 [W
/ M · K]) · AlN (thermal conductivity: up to 160 [W / m ·
K]) and the like. In particular, AlN having high thermal conductivity is desirable because the surface in contact with the plasma is exposed to ion irradiation and radicals and becomes high in temperature.

It is to be noted that a laser can be considered as an excitation source capable of performing a process of low damage similarly to the microwave, having a relatively simple apparatus configuration and obtaining high-density plasma. In the case of a laser, since the frequency is extremely high, reflection from plasma does not need to be considered as seen in a microwave. However, by setting the focal plane (which becomes linear in the event of a failure) at a position distant from the wafer surface as appropriate, an excitation section with a high plasma temperature near the focal plane and a plasma diffusion region around it are formed. And can be treated in the same manner as microwaves. The linear and uniform focusing of the laser can be easily realized by using an optical system combining a transmission refraction system and a catadioptric system. In addition,
Examples of the laser that can be used include a carbon dioxide laser capable of obtaining a high output, a solid-state laser such as a YAG laser, an excimer laser, and a Cu vapor laser. In particular, a carbon dioxide laser is preferable because the optical system is easy to assemble, has a high output, and is easy to handle.

(Separation and Supply of Plural Kinds of Gases) When plasma excitation using microwaves is performed, if the electron density is higher than the cutoff density, the microwaves are reflected by the plasma and cannot propagate through the plasma. At this time, the plasma is excited in a region having a depth several times the skin depth δ = (2 / ωμσ) ^1/2 which is the penetration depth of the microwave from the surface of the plasma. ω is the angular frequency of the microwave, μ is the magnetic permeability, and σ is the conductivity of the plasma.

If the electron density is lower than the cut-off density, that is, if a condition under which microwaves can propagate in the plasma is selected, the plates are irradiated with the microwaves and abnormal heating of the plates occurs, and the reflected waves from the plates and the walls of the chamber are reflected. This causes problems such as the occurrence of a standing wave, non-uniformity of the plasma, and inefficient excitation. Therefore, in order to perform a highly efficient and uniform process, a process using a cut-off mode is performed. At this time, plasma is formed also at a portion other than the δ depth, but this is due to diffusion. Yes, especially the electron temperature is lower than the excitation site.

Generally, when plasma excitation is performed using a gas other than a rare gas, the electron density tends to decrease. In some processes, it is preferable that dissociation does not proceed. That is, it is desirable that a rare gas is present in the excitation section in order to obtain stable plasma, and it is desirable to supply the gas avoiding the excitation section in order to stably supply the gas whose dissociation is to be prevented.

FIG. 5 is a cross-sectional view of an apparatus which enables such a separate supply. A rare gas and a gas for which dissociation should be promoted are supplied from a supply system 500 from a supply system 500 from a supply gas 501. Supply system 500 and supply system 501
Further, by appropriately determining the structure of the supply system 301 and the gas flow rate, it is possible to form a laminar flow structure laminated on the plasma excitation unit 103.

FIG. 6 shows details of the plasma excitation section 103 having a laminated laminar flow structure. The microwave emitted from the plasma emitting surface 600 has an intensity of 1 / e (≒ 0.368) times at the portion 601 where the skin depth has entered, and attenuates exponentially. Therefore, when the distance from the plasma emission surface 600 is several times the skin depth, the excitation of the plasma by the microwave can be ignored. The plasma in a region further than this is diffusion plasma, and has a low electron temperature and is unlikely to dissociate gas molecules. By setting the boundary 602 between the gas flow 605 supplied from the supply system 500 and the gas flow 607 supplied from the supply system 501 and the supply system 301 at a position farther than the region 605 into which the microwave enters, the gas flow The gas molecules contained in 607 move on the plate surface 603 without being dissociated. In particular, when the gas flow 606 and the gas flow 607 are laminar, the exchange of gas molecules contained in the gas flow 606 and the gas flow 607 is suppressed, so that a very high separation effect can be expected.

For example, in the case of CVD, the gas flow 606 is made of a rare gas, and the gas flow 607 is made of various source gases, hydrogen, oxygen,
It is desirable to use an additive gas such as nitrogen. In particular, when performing CVD of a semiconductor or metal, if a raw material gas is contained on the gas flow 606 side, the semiconductor or metal is deposited on the plasma emission surface 600 and absorbs / reflects microwaves. The light does not enter and the plasma cannot be excited. Therefore, in particular, Si epitaxial growth, various S
iO ₂ film, a metal thin film formation, the metal oxide and the nitride film formation, _Si x _H y for use in high-ferroelectric formed shape, Si
H _x Cl _y and organometallic gases such as such dissociation prone gas should be contained in the gas stream 607.

The raw material gas having an organic group has an effect of improving the coating property by the effect of various groups at the time of film formation. Therefore, a higher quality film can be formed because dissociation is not promoted. Becomes The diluent gas is preferably a rare gas having low chemical reactivity. However, since the plasma state and the generated radical species vary depending on the gas species, He, Ne, Ar, Kr and Xe are used in accordance with the source gas and process. Depending on the type, a mixture of several types may be appropriately selected.

In RIE or the like, it is necessary to supply and separate according to the function of the gas. For example, C ₄ F ₈ / CO / O ₂ /
When using the system of the rare gas, radicals which determines the selectivity ratio of Si and other materials is C-CF _x with a C-C bond, by radical CF _x system is better not dissociate. Therefore, in order to prevent dissociation and stabilize the plasma, C ₄ F ₈ / O ₂ is supplied to the gas flow 607 side, and dissociation is preferably promoted to supply C. By supplying the gas to the gas flow 606 side, plasma that realizes etching with a high selectivity can be formed. In addition, by separating and supplying a source gas such as fluorocarbon, a halide such as chlorine / bromine, or CO ₂ or SF ₆ , processing with higher precision becomes possible.

When performing the planarization process of Si,
Performing etching with hydrogen diluted with for example a rare gas, but the Si _x H _y and SiH _x Cl _y slightly added to the process gas, it is possible to improve the effect of flattening by the competitive reaction. In such a case, the additional gas is also supplied in the gas flow 60.
By supplying to the 7 side, film formation on the plasma emission surface 600 can be prevented.

Even when the same gas is used, different effects may be obtained by changing the introduction path depending on the use. For example, when direct oxidation or direct nitridation is performed, radicals and the like generated depending on which gas such as oxygen, nitrogen, hydrogen, ammonia, or fluorine is supplied change.
Even if these gases are supplied to the gas stream 607 which is difficult to dissociate, radicals are formed. The main process in which radicals are formed at this time is an indirect process such as collision of rare gas excited by microwaves with ions and radicals. Generally, radicals directly excited by microwave are radical species.・ Different from density. That is, since a plurality of reaction atmospheres can be realized by the introduction path, film formation with different film formation speeds and film quality can be realized.

When there is a radical ion or the like which is efficiently excited by a specific intermolecular collision, the excited molecule is efficiently excited by supplying the excited molecule to 606 and the molecule to be excited to 607. The excited molecules can be minimized by microwave excitation, and the desired radical ions and the like can be effectively formed. For example, when direct oxidation is performed, a gas obtained by adding a small amount of He to Kr, which is a dilution gas, to 606 is used.
By flowing a gas obtained by diluting oxygen, which is a source gas, with Kr, oxygen radicals that are hardly generated by Kr excitation can be formed, and different film quality and different film formation rates can be obtained. This can be discussed in processes such as hydrogen termination.
By determining the gas supply mode in accordance with the target material and the processing result, it is possible to improve characteristics such as selectivity and film quality.

In any of the processes, especially in a high-pressure process, the mean free path is short, so that ion irradiation on the plate surface can be neglected and a damage-free process is possible. However, if the mean free path cannot be ignored at low pressure and damage due to ion irradiation becomes a problem, the damage can be reduced by using a rare gas having a larger mass and a larger atomic radius, such as Kr or Xe.

(Surface Treatment) In the present embodiment which enables these processes, the portion where moisture adsorption is to be prevented and the device surface which may be exposed to a high concentration of radicals are all formed by adding aluminum to the conventional SUS316L material. ~ 4.16
%) Is formed using a high-concentration aluminum-added stainless steel added, and the temperature is raised to 900 ° C. in an oxidation-reduction competitive atmosphere in which 1 ppm of water is added to 10% hydrogen-added Ar. A passivation film was formed. Thus, with respect to highly corrosive chlorine gas or fluorine gas, also has an excellent corrosion resistance against high concentrations radicals formed by high-density plasma, H ₂
Even if a chamber cleaning using NF ₃ or the like is performed, no metal contamination or the like occurs on the plate. Furthermore, because of its excellent water desorption characteristics and low catalytic properties, a gas such as silane that reacts extremely sensitively to water is also supplied to the process space without deterioration.

It should be noted that a Cr ₂ O ₃ protective film having a high moisture desorption property, an aluminum fluoride / magnesium fluoride mixed protective film on an aluminum-magnesium alloy, a nickel fluoride protective film on a Ni plating surface, and the like are formed into a workable and resistant film. A highly reliable device can be obtained by appropriately selecting a material in consideration of radical properties, moisture adsorption characteristics, catalytic properties, and the like and forming a protective film. An example of the composition, formation conditions, and the like of main protective films will be described.

[Table 1]

(Continuation of a Plurality of Processes) By adopting an apparatus configuration as in this patent, it is possible to easily integrate a plurality of processes in a compact manner. FIG. 7 shows a sectional view thereof, and FIG. 8 shows a perspective view thereof. FIG. 8 shows the separating wall 7.
06 is omitted. Reference numerals 700 to 702 denote chambers each having a structure as shown in FIG. 1, 3 or 5 therein. This also includes auxiliary equipment such as heaters 703 to 705
Comes with.

When the plate is overheated, if the uneven heating induces the occurrence of slip or the like, it is necessary to maintain a uniform temperature in places other than the process section (the contact surface between the plasma excitation section 103 and the plate). is there. Therefore, the heating sequence in 703 is started when all the plates that have proceeded in the direction 709 have entered the heating range of 703, and the heating by 705 is performed until the process of the entire surface of the plate is completed. It is desirable to start a cooling, heat release or heating stop sequence. In particular, when the process temperatures performed in 700, 701 and 702 are different, the configuration as shown in FIG. 7 is desirable. In some cases, the stage that moves integrally with the plate may be provided with a heating mechanism so that heating at 703 or the like may not be performed. In this case, since there is no problem even if the process temperature in each stage is different, the installation interval of the single chamber can be reduced to approximately the length in the plate traveling direction.

For example, even if the process atmosphere is separated from the outside of the chamber as shown in FIG. 5, if the plate surface is exposed to the atmosphere during the transfer between the single chambers, the amount of moisture adsorbed is close to the parallel adsorbed water after one second. Moisture adheres to the plate surface from the atmosphere and brings moisture into the process atmosphere. Therefore, a separating wall 706 is introduced in FIG. As a result, it is possible to prevent moisture adsorption on the wafer during transfer between single chambers. When operating at a pressure lower than the pressure near the atmospheric pressure, the isolation wall 706 is indispensable, and a load lock mechanism is required at the forefront and rearmost portions of the apparatus.

Since the gas coming out of the exhaust port 707 is a high-purity and high-purity purge gas, it can be easily recycled. As a result, the outlets 7 at both ends of the cluster device
Since only 08 discharges gas to the outside, the consumption of purge gas can be reduced.

The present apparatus does not have a mechanism for removing moisture or the like adsorbed on the plate surface when the plate is first introduced. However, such a configuration is sufficient when the first step 700 is performing processes such as water removal using plasma, oxide film removal / separation, or cleaning.

FIG. 9 shows an example of a configuration in which water removal by non-plasma is required at the initial stage. The moisture removing mechanism 900 removes moisture on the plate surface using, for example, lamp irradiation.
An IR lamp or the like may be used. However, in the case where heating of the plate by irradiation of the lamp or the like becomes a problem, an excimer laser or the like that can remove only surface moisture may be used. In addition, even if the water removing mechanism 900 is not provided, a suitable distance is provided from the plate inlet to the chamber 700, and the plate is heated to desorb water and absorb high-purity purge gas flowing from the plate 700. Is also possible.

FIG. 9 also proposes a structure relating to the heating system. When processing at the same process temperature can be performed in a plurality of chambers, the entire region may be heated continuously as in 903. In that case, in order to enable uniform heating over the entire surface of the plate, heating units 901 and 902 capable of raising and lowering the temperature are used.
By installing the front and rear parts respectively, it is possible to perform heating without causing slip, in-plane distortion, and the like.

(Simultaneous processing on both sides) With these methods, it is possible to remove water from the upper surface of the plate. However, if it is difficult to prevent water diffusion from the bottom of the plate as described above,
The configuration as shown in FIG. 10 is employed. The chamber 1000
The plasma excitation section is vertically symmetric with respect to the plate 102. By letting this pass through the plate 102, it is possible to simultaneously remove water from both surfaces of the plate.

This method is effective when water removal, oxide film removal / separation or cleaning is required on both sides of the plate.
It is used in a mixed state with the chamber 700 or the like which only has the upper surface processing. Needless to say, the mechanism related to water removal in these continuous devices can be used for a single chamber.

(Prevention of Accumulation of Reaction By-products, etc.) In this apparatus, it is not always necessary to ensure the uniformity of the gas composition, partial pressure, etc. in the plate traveling direction. Therefore, for example, CV
In the case of D or the like, it can be said that only the necessary amount of the source gas is added to suppress the concentration of the source gas on the exhaust side to an extremely low level.
Reaction products from the IE also accumulate on chamber walls and the like. In many cases, the deposits adversely affect the process, such as forming a dust source in the apparatus.

In CVD (MO-CVD) using an organic metal gas, which has recently been studied, the gas supply path needs to be maintained at a high temperature because the vapor pressure of the liquid gas is low. In contrast, the chamber walls are preferably at 50 ° C.
If the temperature is raised to about 250 ° C, the deposition rate and condensation can be reduced by several orders of magnitude, the frequency of chamber cleaning and maintenance can be drastically reduced, and stable gas supply is possible. Becomes However, irrespective of whether such measures are taken or not, the chamber should be NF ₃ or H
₂ , especially in the case of an organic substance, it is needless to say that the chamber can be kept in a good condition by performing periodic cleaning using plasma to which O ₂ is added.
As a gas added at the time of cleaning, a gas having a cleaning effect on various substances such as fluorocarbon, SF _6, and CO _x is appropriately used.

(System Integration and Line Construction by Continuous Processing Apparatus) As described above, this apparatus can realize a flow operation production line near atmospheric pressure. At this time, film forming, etching, flattening, and cleaning steps other than PVD and anisotropic etching can be configured by the present apparatus. The remaining main processes are exposure, partial cleaning, and ion implantation.

[0099] Since ion implantation can be realized with the same configuration as that of the present apparatus by using, for example, a technique such as laser doping, all steps except PVD and anisotropic etching can be realized under atmospheric pressure. That is, it is possible to construct a line by combining about 80% to 90% of the process in the same manner as the present apparatus, and an ultra-high-speed TAT compact production line, which could not be realized until now, is constructed. In particular, in the production of FPDs including LCDs, since anisotropic etching is not required, atmospheric pressure production can be performed in all steps, and an innovative production line can be constructed.

The purpose of this apparatus is to perform fine processing such as fine circuit processing and micromachining. The plate is used for a semiconductor substrate such as a Si / SiC / diamond / Ge wafer, a compound semiconductor wafer such as GaAs, or a high-speed operation circuit. Needless to say, the same effect can be obtained by using a sapphire substrate, a glass / quartz substrate used for liquid crystal or the like, or a fluorocarbon-based or polyimide-based resin substrate.

Embodiment 2

The cleaning device according to the present invention will be described. This is a cleaning technique called dry cleaning. With the present apparatus, as described above, it is possible to obtain a cleaning effect and a cleaning speed of several orders of magnitude or more in the related art. The choice of gas and its effects in some sub-processes are described.

What is equivalent to the conventional sulfuric acid / hydrogen peroxide cleaning is realized by a plasma process including oxygen in a process gas. High-concentration oxygen radicals excited and generated by microwaves oxidize organic substances adhering to the plate surface and generate H ₂
It decomposes into O, CO _x , NO _x , SO _{x and the} like and is removed from the surface.

Further, what is equivalent to the conventional hydrochloric acid / hydrogen peroxide cleaning is realized by a plasma process containing chlorine or bromine in a process gas. Generally, metal chlorides and bromides in particular have low vapor pressures and easily sublime. Therefore, by forming high-density chlorine radicals or bromine radicals, it is possible to remove inorganic components after oxidizing metal impurities and organic substances on the plate surface. In any case, the flattening process in the present apparatus proceeds by a chemical reaction due to low kinetic energy radicals or ions. Note that the metal surface can be flattened by a similar process. However, since flattening of the metal surface requires a high throughput, it is generally necessary that the source gas concentration, pressure, incident power, and the like be larger than those of cleaning.

Important steps accompanying the cleaning step include removal of a natural oxide film and hydrogen termination. This is both done with dilute hydrofluoric acid. However, in this step, for example, there is a disadvantage that the zeta potential of the silicon surface and the particles is not controlled and the particles removed in the previous step adhere again. On the other hand, if oxide film etching and hydrogen termination are performed using high-density hydrogen radicals excited by microwaves, a hydrogen-terminated surface at the same level as dilute hydrofluoric acid can be formed without particles reattaching.

In the plate cleaning by the present apparatus, organic and inorganic substances can be removed. Particularly, since the cleaning speed is much higher than that of the conventional apparatus, it is possible to deal with even relatively large foreign matter. However, it is difficult to remove particles, which is another factor, only by a plasma process. If the operating pressure of the present apparatus is set to approximately the atmospheric pressure, it can be easily combined with a conventional cleaning apparatus. In addition, since a known low-water-type cleaning device or the like can be directly connected to a transport system of the present device, a complete cleaning process can be realized by incorporating the cleaning device inside the present device. With such a configuration, the time required for evacuation, opening to the atmosphere, and transport between devices can be significantly reduced, and the footprint and the processing time can be reduced.

Conventionally, when plasma is used for dry cleaning,
There were problems such as damage to the film due to high-energy ion collision and dielectric breakdown of the oxide film due to non-uniformity of the plasma. However, in the apparatus of the present invention, the plasma potential itself of the plasma obtained particularly under high pressure conditions is at an extremely low level, and these problems are avoided, and an ideal dry cleaning technique is established.

The present invention can be embodied in various other forms without departing from the spirit or main characteristics thereof. Therefore, the above-described embodiment is merely an example in every aspect, and should not be construed as limiting. The scope of the present invention is defined by the appended claims, and is not limited by the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

【The invention's effect】

By using the present apparatus, for example, most of the process for forming a fine circuit of a semiconductor can be made an atmospheric pressure process, and since processing over a large diameter can be performed, productivity can be dramatically improved.

[Brief description of the drawings]

FIG. 1 is a sectional view in the plate advancing direction near a process space.

FIG. 2 is a vertical cross-sectional view in the plate advancing direction near a process space.

FIG. 3 is a sectional view of a device having a different pressure control method.

FIG. 4 is a perspective view of a microwave supply unit.

FIG. 5 is a cross-sectional view of an apparatus employing a separate supply.

FIG. 6 is a conceptual diagram of a process space at the time of separation supply.

FIG. 7 is a cross-sectional view of a clustered device.

FIG. 8 is a perspective view of a clustered device.

FIG. 9 is a sectional view of a continuous processing apparatus into which a moisture removing mechanism is introduced.

FIG. 10 is a cross-sectional view of an apparatus capable of performing double-sided simultaneous processing.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 chamber wall 101 plasma generating section 102 plate (stage) 103 plasma exciting section 104 transfer device 200 chamber side wall 300 gas introduction path (downstream seal gas supply) 301 gas introduction path (upstream seal gas supply) 400 H-plane slot antenna 401 Slot 402 Uniform line 403 Plasma excitation unit 404 Uniform line side wall 405 Center line 500 Supply system (dissociated gas) 501 Supply system (non-dissociated gas) 600 Plasma radiating surface 601 Plasma entry region boundary 602 Gas flow boundary 603 Plate surface 604 Gas Advancing direction 605 Plasma invasion area 606 Dissociated gas flow 607 Non-dissociated gas flow 700 Chamber 1 701 Chamber 2 702 Chamber 3 703 Auxiliary 1 704 Auxiliary 2 705 Auxiliary 3 706 Separation wall 707 Exhaust port 708 Exhaust Mouth 709 Plate advancing direction 900 moisture removing mechanism 901 foremost heating unit 902 the last portion heating part 903 continuous heating section 1000 double-sided simultaneous processing chamber

Continued on the front page F term (reference) 4E001 LH00 NA01 5F004 AA01 AA16 BA20 BB11 BB24 BC04 BC06 BD04 CA02 CA05 DA00 DA01 DA02 DA03 DA15 DA16 DA17 DA18 DA22 DA23 DA24 DA25 DA26 5F045 AA09 AA13 AC01 AC05 AC11 AC12 AC15 AC16 AE17 AE17 AE17 AE21 AE23 AE25 AE29 AF03 AF08 BB02 BB09 DP23 DQ15 EF01 EF17 EH05 EH10 EM01 HA24 HA25

Claims (33)

[Claims] A linear plasma is formed using an electromagnetic wave, and while a workpiece surface is kept horizontal to the linear plasma,
A plasma processing apparatus for performing surface processing on a workpiece while moving a relative position between the workpiece and the plasma. 2. The plasma processing apparatus according to claim 1, wherein the electromagnetic wave is a microwave. 3. The plasma processing apparatus according to claim 1, wherein the electromagnetic wave is a laser. 4. The plasma processing apparatus according to claim 1, wherein the operating pressure is 0.1 mTorr or more. 5. The plasma processing apparatus according to claim 1, wherein the operating pressure is substantially atmospheric pressure. 6. The process according to claim 1, wherein the film is formed directly on the surface of the workpiece by plasma using a mixed gas of at least one of oxygen, nitrogen, ammonia, hydrogen and fluorine and a rare gas. Plasma processing equipment. 7. The plasma processing method according to claim 1, wherein a CVD film is formed on the surface of the workpiece by plasma using a source gas and a mixed gas of at least one of hydrogen, oxygen, and nitrogen and a rare gas. Processing equipment. 8. The plasma processing apparatus according to claim 1, wherein the workpiece surface is etched by plasma using a mixed gas of a source gas, at least one of hydrogen and oxygen, and a diluent gas. 9. A method using at least one of cleaning of a workpiece surface and flattening of a metal surface by plasma using a mixed gas of a source gas and at least one of hydrogen and oxygen and a diluent gas. The plasma processing apparatus according to claim 1. 10. The method according to claim 1, wherein at least one of planarization of a workpiece surface, removal of a natural oxide film, and hydrogen termination is performed by plasma using a mixed gas of a diluent gas and hydrogen. Plasma processing equipment. 11. The plasma processing apparatus according to claim 1, wherein the processing apparatus is cleaned by plasma using a mixed gas of a source gas, at least one of hydrogen and oxygen, and a diluent gas. 12. The method according to claim 12, wherein the dilution gas is He.Ne.Ar.K.
The plasma processing apparatus according to claim 6, wherein at least one of r and Xe is included. Wherein said raw material _gas, Si _x H _y, SiH _x
The plasma processing apparatus according to claim 7, wherein at least one of _Cly and an organometallic gas is contained. 14. The plasma processing apparatus according to claim 8, wherein the source gas contains at least one of NF ₃ , fluorocarbon, SF _6, and CO _x . 15. The plasma processing apparatus according to claim 8, wherein said source gas contains a halogen-based element. 16. The plasma processing apparatus according to claim 15, wherein said halogen gas is chlorine and bromine. 17. the raw material gas, _Si x _{H y} and Si
The plasma processing apparatus according to claim 10, characterized in that it comprises at least one of H _x Cl _y. 18. The plasma processing apparatus according to claim 1, wherein an effective process speed is controlled by changing a radiation surface width of the electromagnetic wave. 19. The plasma processing apparatus according to claim 1, wherein airtight sealing is performed by forming a viscous flow in a gap between the workpiece and the apparatus. 20. The plasma processing apparatus according to claim 1, wherein the workpiece is fixed to a stage that moves integrally. 21. The plasma processing apparatus according to claim 2, wherein the microwaves are supplied in substantially the same phase over the entire radiation surface to the plasma. 22. The plasma processing apparatus according to claim 1, wherein a protective film having high corrosion resistance is formed on a surface of a member of the workpiece transfer device. 23. The plasma processing apparatus according to claim 1, wherein at least two or more of the plasma processing apparatuses according to claim 6 are connected to perform a plurality of processes continuously. 24. The plasma processing apparatus according to claim 1, wherein a water removing mechanism is connected. 25. The gas contact part in the apparatus is set at 50 ° C. to 250
The plasma processing apparatus according to claim 1, wherein the plasma processing apparatus is heated to a temperature of ° C. 26. The plasma processing apparatus according to claim 1, wherein the shape of the workpiece is a plate. 27. The plasma processing apparatus according to claim 1, wherein at least a part of the workpiece is a semiconductor. 28. The plasma processing apparatus according to claim 1, wherein at least a part of the workpiece is silicon. 29. The plasma processing apparatus according to claim 1, wherein at least a part of the workpiece is a glass substrate. 30. The plasma processing apparatus according to claim 1, wherein at least a part of the workpiece is a resin substrate. 31. In a plasma excited by an electromagnetic wave, a gas laminar flow comprising at least two layers is formed in a plasma forming portion, and a gas type to be supplied to each gas flow is selected, thereby dissociating and exciting a source gas. A plasma processing apparatus characterized by controlling the following. 32. A manufacturing process, wherein at least a part of a workpiece is processed by the plasma processing apparatus according to claim 6 to 11, 23 to 25, and 28. 33. A device, at least a part of which is processed by the plasma processing apparatus according to claim 6 to 11, 23 to 25, and 28.