KR20090037343A - Magnetized inductively coupled plasma processing apparatus and generating method - Google Patents

Abstract

A magnetized inductively coupled plasma process device and a plasma generating method thereof are provided to obtain a uniform plasma distribution by using a permanent magnet. A magnetized inductively coupled plasma device includes a vacuum chamber(200), a sample mounting unit(205), an antenna(210), a pair of permanent magnets(230,235), and a side magnet(250). The sample mounting unit is positioned inside the vacuum chamber. An antenna generates the plasma in the vacuum chamber. A pair of permanent magnets are arranged in the bottom of the upper part of the antenna and the lower part of the vacuum chamber. The pair of permanent magnets form the magnetic field in the vertical direction of the vacuum chamber. The pair of permanent magnets have the opposite polarity. The side magnet is arranged in the side of the vacuum chamber. The side magnet forms a multi polar surface magnetic field in the vertical direction to the vacuum chamber.

Description

Magnetized inductively coupled plasma processing apparatus and plasma generating method {MAGNETIZED INDUCTIVELY COUPLED PLASMA PROCESSING APPARATUS AND GENERATING METHOD}

The present invention relates to an inductively coupled plasma processing apparatus and a method of generating the same, and more particularly, to facilitate the generation of high density plasma at low pressure, and to improve the uniformity of the plasma distribution for a sample. The present invention relates to an apparatus and a method for generating the same, which allow a plasma field to be uniformly applied to the entire area of a sample by generating a magnetic field in the generating space.

Plasma generators include Helicon and microwave plasma sources using capacitively coupled plasma sources, inductively coupled plasma sources, and plasma waves. plasma source). Among them, inductively coupled plasma generators capable of easily forming high-density plasmas are widely used.

FIG. 1 illustrates an inductively coupled plasma generator that is generally used. The inductively coupled plasma generator 1 reacts into a chamber 101 in which a plasma 106 is generated and into the chamber 101. A gas inlet 102 for supplying gas and a vacuum pump 103 for maintaining the inside of the chamber 101 in a vacuum and discharging the reaction gas when the reaction is terminated. In addition, a substrate holder 105 for placing a substrate 104 (for example, a wafer) to be processed is installed in the chamber 101, and an RF power source 109 is disposed above the chamber 101. This connected antenna 107 is provided.

When power is added from the RF power source 109 with impedance matching 108 to the antenna 107, RF power, that is, RF potential and current, is applied to the antenna 107. The applied RF potential forms a time-varying electric field in the vertical direction of the dielectric 110 separating the antenna 107, and the RF current flowing through the antenna 107 is a magnetic field in the internal space 111 of the reaction chamber 101. And the magnetic field creates an induction electric field.

At this time, the reaction gas inside the chamber 101 obtains sufficient energy for ionization from the induction generated electric field and forms the plasma 106. The formed plasma 106 is incident on the substrate 104 installed in the substrate holder 105 by another RF power source 112 applying a negative DC bias voltage to process the substrate 104.

On the other hand, the plasma 106 formed in the chamber 101 is more dense by the induced electric field by the magnetic field than the electric field formed in the chamber 101. Such a plasma is called an inductively coupled plasma and such equipment is called an inductively coupled type. It is called a plasma generator or a plasma generator. This plasma generator has the advantage of being able to form a high density plasma at a high operating gas pressure, but when the gas pressure is lowered, there is a disadvantage that it is difficult to ignite and maintain the plasma.

FIG. 2 illustrates a planar spiral antenna which has been widely used in the plasma generator. In the planar spiral antenna, electromagnetic waves are largely formed at the center portion, and thus the density distribution of the inductively coupled plasma generated is not uniform in space, and the density is high at the center portion and decreases toward the edge of the reactor.

Therefore, in order to process a large area substrate of 300 mm or more, it is required to form a plasma having a uniform distribution in a space corresponding to at least the substrate area, but the aforementioned flat spiral antenna does not satisfy such a condition. have.

To solve this problem, various types of antennas have been disclosed. For example, Korean Patent Application No. 7010807/2000 discloses a transformer coupled balanced antenna in which the planar spiral antennas are arranged in parallel (see FIG. 3), and Korean Patent Application No. 14578/1998 forms a radiation structure. A large area planar antenna is disclosed (see FIG. 4). In addition, Korean Patent Application No. 35702/1999 discloses an antenna combined in a parallel form (see FIG. 5).

However, the problem that occurs in operating this kind of antenna is a difficulty in matching the antenna and the input power, and the carved antennas are a problem due to the disturbance of electromagnetic waves generated between the antennas, a difficulty in manufacturing, and an antenna combination when driving for a long time. If some of the antenna characteristics are changed independently, there is a problem in the stability of the operation can not be adjusted. In addition, the parallel antenna is composed of several antenna coil wires. Therefore, in order to adjust the phase of the input current flowing through each parallel antenna line from the antenna input end to the output end, an inductor or a capacitor is independently attached to each line of the parallel antenna. This attachment condition also narrows the operating area of the reactor.

Therefore, the shape of the antenna using one input terminal and the other output terminal is most ideal, but it is difficult to control the plasma density of the central part by controlling the formation of a large induced electric field in the center portion generated by the spiral antenna. There is a problem in that the plasma distribution or density is difficult.

An object according to an embodiment of the present invention for solving the above problems is a problem that it is difficult to ignite the plasma and to generate and maintain the high-density plasma when the gas pressure is low in the inductively coupled plasma processing apparatus, and in the planar spiral antenna The present invention provides a magnetized inductively coupled plasma processing apparatus and a plasma generating method capable of improving the problem of having a non-uniform distribution in the form of a high density and rapidly decreasing toward the edge due to the generated induction electric field.

Another object according to an embodiment of the present invention is to simplify the installation of an apparatus for forming an external magnetic field with a plasma confinement effect, and to easily perform maintenance work in the event of a problem with the apparatus. The present invention provides a magnetized inductively coupled plasma processing apparatus and a plasma generating method capable of forming a uniform plasma distribution by a change in shape and arrangement.

Inductively coupled plasma processing apparatus according to an embodiment of the present invention for solving the above problems is a vacuum chamber; Sample mounting means provided in the vacuum chamber; An antenna generating a plasma inside the vacuum chamber; And at least one pair of permanent magnets disposed above the antenna and below the vacuum chamber and having opposite poles to form a magnetic field in a vertical direction of the vacuum chamber.

Furthermore, it may further comprise at least a pair of side magnets disposed on the side of the vacuum chamber and forming a multipolar surface magnetic field in a direction perpendicular to the axis of the vacuum chamber, wherein the side magnets have a polarity of neighboring magnets. It can be arranged oppositely.

Furthermore, the non-conductive window may further include a non-conductive window for isolating the antenna and the reaction chamber included in the vacuum chamber in which the plasma is generated and passing the induced electromotive force of the antenna, wherein the non-conductive window is planar or critical. It may have a cotton form.

In this case, the antenna may be located above the vacuum chamber or inside the reaction chamber where the plasma generated in the vacuum chamber is generated.

At this time, the permanent magnet is in the form of any one of a plurality of linear and at least one serpentine arranged in parallel or in the form of at least one concentric circle, at least one concentric square and at least one spiral. Can be arranged.

Here, the magnetic field strength formed in the vertical direction of the vacuum chamber may be 0.2 to 10 times the magnetic field strength at which the radio frequency applied to the antenna becomes an electron cyclotron frequency.

A plasma generating method according to an embodiment of the present invention, the plasma generating method of the inductively coupled plasma processing apparatus, comprising the steps of: (a) injecting a reaction gas on the upper sample inside the reaction chamber of low pressure; (b) generating electromagnetic waves with the reaction gas using an antenna supplied with RF power; (c) The image of the sample to be uniform on the distribution of the plasma generated by the electromagnetic wave, and to be formed on top of the sample. It may include the step of applying a magnetic field in the vertical direction of the reaction chamber by using a permanent magnet located at the bottom.

Furthermore, the method may further include applying a multipolar surface magnetic field in a direction perpendicular to the axis of the reaction chamber by using the plurality of side magnets mounted on the side of the reaction chamber.

Here, the multipolar surface magnetic field may be applied in a direction perpendicular to the axis of the reaction chamber by using the plurality of side magnets having opposite polarities of magnets adjacent to each other mounted on the side of the reaction chamber.

In addition, the magnetic field applied in the vertical direction of the reaction chamber may be applied to increase the density of the magnetic flux flux as the radial direction away from the center of the sample.

By providing the plasma processing apparatus and the method of generating the same according to the present invention, it is easy to generate and maintain a high-density plasma at low pressure, and to improve the uniform distribution easily in the uneven distribution in the reaction chamber of the plasma density. You can do it.

In addition, the installation of an apparatus for forming an external magnetic field that has a plasma confinement effect is simplified, and the apparatus can be easily repaired in the event of a problem, and a more uniform plasma distribution can be achieved by a simple change in shape and arrangement. Can be formed.

Other objects and features of the present invention in addition to the above object will be apparent from the description of the embodiments with reference to the accompanying drawings.

Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, a magnetized inductively coupled plasma processing apparatus and a plasma generating method according to an embodiment of the present invention will be described in detail with reference to FIGS. 6 to 11.

6 is a diagram illustrating a configuration of an inductively coupled plasma processing apparatus as an embodiment according to the present invention. As shown in FIG. 6, the present invention includes a vacuum chamber 200, a sample mounting means 205 provided inside the vacuum chamber 200, and a planar antenna positioned above the vacuum chamber 200 to generate plasma. (210), the antenna and the reaction chamber 201 to isolate the non-conductive window 240 for passing the induced electromotive force of the antenna 210, the direction disposed on the side of the vacuum chamber 200 and perpendicular to the axis of the chamber At least one side magnet 250 forming a multipolar surface magnetic field, an upper portion of the antenna 210 and a lower portion of the reaction chamber 201, and parallel to the axis of the reaction chamber 201. The configuration includes at least a pair of permanent magnets 230 and 235 having opposite poles to allow a magnetic field to be formed in one direction.

Here, the vacuum chamber 200 includes both the portion in which the antenna 210 is formed and the reaction chamber 201, although the vacuum chamber 200 and the reaction chamber 201 may be used under the same name, Since the reaction chamber 201 of the vacuum chamber 200 is used as a term referring to the portion where the actual plasma is generated in the detailed description of the present invention, the vacuum chamber 200 and the reaction chamber 201 are used separately. Of course, when the non-conductive window 240 does not exist, the vacuum chamber 200 may be the reaction chamber 201.

In this case, a part of the vacuum chamber 200 in which the non-conductive window 240 upper antenna is formed may maintain a vacuum or atmospheric pressure state.

More specifically, the spiral-shaped planar antenna 210, a power supply (not shown) for applying power to the antenna 210, a low pressure reaction (etch or deposition) chamber 201, and the antenna A non-conductive window (eg quartz window) 240 isolating the reaction chamber 201 but allowing the induced electromotive force of the antenna 210 to pass through, an electrode (not shown) for etching or deposition, and an impedance matching circuit of the antenna (not shown). Radio frequency power supply (not shown) for applying a bias to the electrode, a radio frequency shield (not shown) for the antenna, and a side magnet generating a multipolar surface magnetic field in a direction perpendicular to the axis of the chamber. 250) and permanent magnets 230 and 235 which generate an external magnetic field in a direction parallel to the axis of the chamber.

In this case, as shown in FIG. 6, the nonconductive window 240 may include not only a flat window but also a non-planar window, for example, a dome window.

In addition, although the antenna for generating plasma is described as a planar antenna in this embodiment, the antenna is not limited to the planar antenna and may include a non-planar antenna. For example, a non-planar helical antenna or a non-planar concentric antenna that is suitable for the dome shape may correspond to the window of the dome shape. In this case, a plurality of concentric antennas may be used to form a non-planar shape.

In addition, although the planar antenna is described in a spiral form in this embodiment, other types of antennas, for example, a plurality of linear antennas, serpentine antennas, and the like may be used to generate a plasma, and the form of the antenna is a reaction chamber. It may be determined by the shape of the. For example, when the reaction chamber is cylindrical, a spiral antenna, a plurality of concentric antennas, or the like may be used, and when the reaction chamber is a rectangular cylinder, a plurality of linear antennas, a snake antenna, or the like may be used to generate plasma inside the reaction chamber. have.

Hereinafter, the principle of generating plasma through the structure of the apparatus according to the embodiment shown in FIG. 6 will be described.

Plasma, which is a collection of ions, electrons and neutral particles, is widely applied to energy, lighting, environment, indicator, heat source, new material synthesis, thin film manufacturing, semiconductor etching process, and so on. Varies. Plasma used in semiconductor etching process and value-added thin film deposition mainly uses electric current and voltage source such as ultra high frequency and radio frequency, and transfers power to plasma by various mechanisms.

Therefore, the characteristics of plasma (electron density, electron temperature, operating pressure, ion current density, ion energy, type of active species, density of active species, plasma uniformity) are determined according to the power delivery method and discharge type. The success of the process depends on the nature of the plasma produced.

An inductively coupled plasma processing apparatus includes an antenna, an antenna power source, a chamber for low pressure treatment (etching or deposition) isolated between an antenna and a non-conductive window (e.g. a quartz window), and a radio frequency power source for the treatment electrode. And the like. In the inductively coupled plasma processing apparatus, a radio frequency (a few MHz to several tens of MHz) current is transmitted to an antenna through an impedance matching circuit from outside, and is a non-conducting chamber of a ceramic system such as a quartz window, and is isolated from the outside. Plasma can be obtained by passing an induced electromotive force through.

In the case of the above-described inductively coupled plasma processing apparatus, the induced electromotive force does not penetrate deeply into the plasma in the processing chamber, and usually exists only within a few cm below the quartz window, and the penetration depth is

(Ω _pe , υ, c, and ω are the plasma frequency, the collision frequency, the speed of light, and the applied radio frequency, respectively).

Therefore, in the conventional plasma processing apparatus, induction electromotive force is deeply penetrated into the processing chamber to improve the defect that uniform induction of plasma cannot be generated at high density as the induced electromotive force does not penetrate deeply into the processing chamber. An apparatus for magnetizing plasma has been developed to generate. [Reference Patent: Republic of Korea Patent Registration Number: 10-0178847]

By using several spirally wound planar antennas, at least one pair of coil electromagnets can apply a magnetic field perpendicular to the antenna to the processing chamber to effectively magnetize the plasma.

When the plasma is magnetized by an external magnetic field, a conductivity tensor or dielectric tensor, which determines the properties of the plasma, is given by the following equation.

Electrical Conductivity of Plasma Without Magnetic Field

(Where n, e, ω, υ _m and ω _ce are the electron density, charge amount, externally applied electromagnetic frequency, collision frequency, and electron cyclotron rotation frequency, respectively).

When the properties of the plasma are changed in this way, electromagnetic waves can be transferred into the plasma, thereby increasing the penetration depth of the induction field and the induction field, and controlling the size of the magnetic field. Therefore, the plasma volume at which power transfer takes place is greatly enlarged.

The real or imaginary part (which represents energy absorption) of the wave number of the generated electromagnetic waves is derived from the dielectric tensor, and the collision frequency and electron

Density, magnetic field strength. The wavelength in the region where the device is mainly operated (sub mTorr-several tens of mTorr, input power: 100W-several kW, magnetic field: several-tens of Gauss) is about several-several tens of centimeters.

In addition, since the external magnetic field is present throughout the reaction chamber, the radial loss of electrons is reduced, and as a result, the plasma potential is lowered, and thus the ion loss is also reduced, thereby generating a uniform high-density plasma.

However, it is difficult to install a pair of coil electromagnets, etc., which form an external magnetic field, and there is a problem that it is not easy to repair or correct when a problem occurs. More importantly, the magnetic field strength distribution in the radial direction can be freely designed There are no drawbacks.

Therefore, in the present invention, in order to improve the uniformity of the plasma distribution by the induced electromotive force, at least one pair of permanent magnets, which can facilitate the shape and arrangement of the permanent magnets, may be disposed in the upper and lower portions of the reaction chamber, and the shape may be changed according to the plasma distribution. To configure the system.

7 is a view illustrating a shape of a permanent magnet cross section forming an external magnetic field in the inductively coupled plasma processing apparatus according to an embodiment of the present invention.

As shown in FIG. 7, the permanent magnet is arranged by disposing the permanent magnets arranged in several circular or at least one rotating spirals having the same center at different polarities of the magnets directed inwardly at the upper and lower portions of the reaction chamber. It is possible to form a magnetic field in a direction parallel to the. The distribution of the magnetic flux can be changed according to at least one of the shape and arrangement of the permanent magnets, which can have a significant effect on the plasma distribution.

A permanent magnet is a magnet that generates and maintains a stable magnetic field without receiving electrical energy from the outside. A magnet with a very small ability to maintain magnetization for a permanent magnet is called a temporary magnet. In contrast to materials with high permeability, permanent magnets are suitable not only for high residual magnetism (thousands to 10,000G) but also for high coercivity (hundreds of Oe). Nico (alloy of aluminum, nickel, cobalt, copper), quinipe (alloy of copper, nickel, iron), S _m -Co, Nd-Fe-B, and the like.

In other words, it refers to a magnet that can permanently form a magnetic field in the magnetic body instead of forming a magnetic field by receiving electric energy from the outside like an electromagnet by a conventional coil. In the present invention, such a permanent magnet can be used to not only make the plasma distribution uniform, but also to form an external magnetic field more easily.

On the other hand, if you look at the principle of forming a plasma in the reaction chamber, a gas having a pressure of several hundred mTorr in the sub-mTorr inside the reaction chamber, and after applying a low voltage to the antenna and gradually increasing the voltage, over a certain voltage The inside of the reaction chamber emits light as plasma is generated in all regions except the tube wall and the vicinity of the electrode. This phenomenon is called gas discharge.

In the light emitting region, the gas is ionized so that the density of electrons and ions is dramatically increased than before discharge occurs. Here, the term "discharge" means that electrons constituting a gas atom or molecule obtain energy from the outside, thereby releasing the bonds of atoms or molecules, and continuously forming a large number of free electrons. That is, by ionization, gas atoms and molecules become positive ions and electrons, and the ionized gas is called an ionizing gas or plasma. The charged particle density of the ionized gas in the emitting region is quite large (about 10 ⁹ / cm ³ in fluorescent lamps) and maintains electrical neutrality as a whole.

In the plasma, the average density of electrons and the average density of ions are the same (the density of neutral particles is much larger than these). This is called plasma density. In addition, there is a thin layer of non-emission region around the plasma, which seems to surround the plasma. This area is called Sheath. Sheath is depleted of electrons, so the ionization by electrons hardly occurs. Therefore, the charged particles have a low density, are not electrically neutral, and no glow is observed. Sheaths are not only formed on the cathode, but on all contacts such as anodes, conductors, and insulators exposed to the plasma.

As described above, in the plasma processing apparatus of the present invention, as shown in FIG. 6, the magnetic force lines generated by the permanent magnets 230, 235, and 250 react with the permanent magnets by placing the permanent magnets on the outer side of the reaction chamber 201 or on the outside of the upper and lower surfaces. It is also possible to arrange so as to form an optimal shape in the chamber.

Polarities of the upper permanent magnets 230 and the lower permanent magnets 235 are opposite to each other in the polarity toward the reaction chamber 201, so that the lines of magnetic force inside the chamber may be straight in the axial direction of the reaction chamber 201. .

On the other hand, in the case of the permanent magnets of the side magnets 250, the polarities of the neighboring magnets cross the polarities toward the reaction chamber 201, thereby effecting plasma confinement by the multipole surface magnetic field to reduce the plasma loss in the chambers. It is possible to increase the plasma density and to improve the radial uniformity.

표류(drift) 운동을 야기하여, 반응 챔버(201) 축에 대한 회전 방향과 반경방향 으 로 균일도를 향상시키며, 이온화 반응을 촉진시키는 역할을 하게 된다.The magnetic force lines generated by the upper permanent magnet 230 and the lower permanent magnet 235 have components in the axial direction as well as the radial direction of the reaction chamber 201, which is the axis of the reaction chamber 201 in the sheath. Electrons by directional electric and radial magnetic fields

By causing the drift (drift) movement, it improves the uniformity in the direction of rotation and radial direction about the reaction chamber 201 axis, and serves to promote the ionization reaction.

8 is a cross-sectional view showing an arrangement of permanent magnets according to another embodiment of the present invention. As shown in FIG. 8 (a), the permanent magnets are arranged in several tetrahedrons having the same center, and the cross section is formed in the form of several square rings having the same center. This shape is a shape which can make the radial distribution of an electron or ion uniform like the concentric permanent magnet shown in FIG. FIG. 8 (b) also shows a permanent magnet arranged in a labyrinth shape, in which the strength of the magnetic field formed in the vertical direction of the reaction chamber 201 is uniformly formed in the radial direction at least once. Unlike the shape illustrated in the drawings, such a structure can of course be shaped into various symmetrical structures in the radial direction.

In the plural concentric or helical permanent magnet arrangements described above, when the spacing between the magnets becomes narrower as the distance between the magnets increases in the radial direction, the density of the magnetic flux becomes higher as the distance in the radial direction increases. The effect of improving the uniformity can be obtained (not shown).

Here, the upper and lower permanent magnets may be arranged in a form other than those shown in FIGS. 7 and 8. For example, a plurality of linear permanent magnets may be arranged in parallel or a grid, for example, a rectangular lattice form. Or honeycomb (hexagonal) lattice.

In addition, the arrangement of the upper and lower permanent magnets may vary depending on the shape of the reaction chamber. For example, in the case of a cylindrical chamber, as shown in FIG. 7, a plurality of concentric circles or spiral permanent magnets are used, and a rectangular In the case of a cylindrical chamber, any one of tetrahedral and maze-type permanent magnets, a plurality of linear permanent magnets, and a lattice permanent magnet shown in FIG. 8 may be used.

Of course, the placement density of the permanent magnets may be different in order to improve the plasma treatment uniformity at the center and the peripheral circumference of the reaction chamber, and it is preferable that the upper permanent magnet and the lower permanent magnet are opposite to each other and directed into the reaction chamber.

(여기서, B, m, e, f는 자기장세기, 전자의 질량, 전하, 주파수를 말한다.)의 0.2~10배 사이 값을 갖는 자기장이 형성되도록 영구자석의 세기 및 위치 등을 선택할 수 있다.At this time, the shape and arrangement of the upper permanent magnet and the lower permanent magnet may vary depending on the strength of the vertical and vertical vertical magnetic fields in the reaction chamber. The magnetic field in which the radio frequency applied to the device is the electromagnetic cyclotron frequency. Century that is,

(Where B, m, e, and f represent magnetic field strength, mass of electrons, charge, and frequency). The strength and position of the permanent magnet may be selected to form a magnetic field having a value between 0.2 and 10 times.

Here, when a radio wave having a separate frequency is applied to the antenna and the substrate support, the frequency f for calculating the strength of the magnetic field is preferably used as the frequency of the radio wave having a large output.

9 is a view illustrating a configuration and magnetic flux distribution of an inductively coupled plasma processing apparatus as another embodiment according to the present invention.

As shown in FIG. 9, the present invention includes a vacuum chamber 300, a sample mounting means 305 provided inside the vacuum chamber 300, and a planar antenna positioned above the vacuum chamber 300 to generate plasma. (310), the non-conductive window 340 isolating the antenna and the reaction chamber 301 to pass the induced electromotive force of the antenna 310, the direction disposed on the side of the vacuum chamber 300 and perpendicular to the axis of the chamber At least one side magnet 350 to form a multipolar surface magnetic field, an upper portion of the antenna 310 and a lower portion of the vacuum chamber 300, and form a magnetic field in a direction parallel to the axis of the vacuum chamber 300. At least one pair having opposite poles to enable each other, the configuration includes a concentric or spirally arranged permanent magnets (330, 335) become thicker or more closely arranged as the cross-section is farther from the center.

The side magnet 350 may be an electromagnet, it is also possible to be a permanent magnet. As described above, the side magnet has the polarity of the neighboring magnets crossing the polarity toward the inside of the reaction chamber, thereby giving the plasma confinement effect by the multipolar surface magnetic field to reduce the plasma loss in the chamber to increase the plasma density, and the radial density. It can serve to improve the uniformity.

In addition, the upper and lower permanent magnets 330 and 335 are arranged so that the magnetic field is formed from the upper to the lower direction by changing the polarity, the plasma density of the central portion due to the conventional induction electric field is high and non-uniform in the form of sharply decreasing toward the edge In order to solve the problem of having a distribution, the thickness of the permanent magnet cross section is thickened or has a shape arranged closely.

FIG. 10 is a view showing a concentric circle or spiral shape as an embodiment of a permanent magnet forming a vertical magnetic field of the plasma processing apparatus of the present invention. As shown in FIG. 10, the cross-sectional thickness of the permanent magnet corresponding to the embodiment of FIG. 7 becomes thicker as it moves away from the center, and the cross-section has a circular shape.

FIG. 11 is a view showing a rectangular concentric or spiral shape as another embodiment of a permanent magnet forming a vertical magnetic field of the plasma processing apparatus of the present invention. As shown in FIG. 11, the cross-sectional thickness of the permanent magnet corresponding to the embodiment of FIG. 8 becomes thicker as it moves away from the center, and the cross-section has a rectangular shape.

표류(drift) 운동이 커지게 됨으로써, 플라즈마의 밀도가 높아지게 되어 전체적으로 플라즈마 분포가 시료 전 영역에서 균일하게 되는 효과가 있다.As long as the shape is symmetric in the radial direction depending on the shape of the sample to be processed, any shape is possible and is not limited to the embodiment of the drawings. In other words, increasing the density of magnetic flux at the top of the sample increases the strength of the magnetic field per unit area, and the interaction of the electric and magnetic fields in this region

As the drift movement is increased, the density of the plasma is increased, so that the plasma distribution is uniform throughout the entire sample area.

The cross-sectional shape of the permanent magnet described above can be not only the shape shown in the embodiment, but also an appropriate shape for improving the uniformity of the plasma distribution.

In the detailed description of the present invention, the antenna for generating a plasma is described with reference to embodiments in which the antenna is positioned above the non-conductive window, which is isolated from the reaction chamber, but the present invention is not limited thereto. Those skilled in the art will appreciate that they may be located at.

The magnetized inductively coupled plasma processing apparatus and the plasma generating method according to the present invention can be modified and applied in various forms within the scope of the technical idea of the present invention and are not limited to the above embodiments. In addition, the embodiments and drawings are merely for the purpose of describing the contents of the invention in detail, not intended to limit the scope of the technical idea of the invention, the present invention described above is common knowledge in the technical field to which the present invention belongs As those skilled in the art can have various substitutions, modifications, and changes without departing from the spirit of the present invention, it is not limited to the embodiments and the accompanying drawings. And should be judged to include equality.

1 is a view showing an inductively coupled plasma generator that is generally used in the prior art,

FIG. 2 illustrates a planar spiral antenna which has been widely used in a conventional plasma processing apparatus.

3 is a diagram illustrating a transformer coupled balanced antenna having the planar spiral antennas arranged in parallel with Korean Patent Application No. 7010807/2000;

4 is a view showing a large area planar antenna in the form of a radiation structure of Korean Patent Application No. 14578/1998;

5 is a view showing an antenna combined in a parallel type of Korean Patent Application No. 35702/1999,

6 is a diagram illustrating a configuration of an inductively coupled plasma processing apparatus as an embodiment according to the present invention;

7 is a view illustrating a shape of a permanent magnet array cross section forming an external magnetic field in the inductively coupled plasma processing apparatus according to the present invention;

8 is a cross-sectional view showing an arrangement of a permanent magnet as another embodiment according to the present invention;

9 is a view illustrating a configuration and magnetic flux distribution of an inductively coupled plasma processing apparatus as another embodiment according to the present invention;

10 is a view showing a concentric circle or spiral shape as an embodiment of a permanent magnet forming a vertical magnetic field of the plasma processing apparatus of the present invention;

FIG. 11 is a view showing a rectangular concentric or spiral shape as an example of a permanent magnet forming a vertical magnetic field of the plasma processing apparatus of the present invention.

<Description of Symbols for Main Parts of Drawings>

200: vacuum chamber

201: reaction chamber

205: sample mounting means

210: antenna

230, 235: permanent magnet

240: non-conductive window

250: side magnet

Claims (19)

A vacuum chamber; Sample mounting means provided in the vacuum chamber; An antenna generating a plasma inside the vacuum chamber; And At least a pair of permanent magnets disposed above the antenna and below the vacuum chamber and having opposite poles to form a magnetic field in a vertical direction of the vacuum chamber; Inductively coupled plasma processing apparatus comprising a. The method of claim 1, At least one pair of side magnets disposed on the vacuum chamber side and forming a multipolar surface magnetic field in a direction perpendicular to the axis of the vacuum chamber Inductively coupled plasma processing apparatus further comprising. The method of claim 2, The side magnet is Inductively coupled plasma processing apparatus that is an electromagnet or a permanent magnet. The method of claim 2, The side magnet is An inductively coupled plasma processing apparatus in which polarities of neighboring magnets are opposite to each other. The method of claim 1, A non-conductive window that isolates the antenna and the reaction chamber included in the vacuum chamber in which the plasma is generated and passes the induced electromotive force of the antenna Inductively coupled plasma processing apparatus further comprising. The method of claim 5, The non-conductive window is High frequency inductively coupled plasma processing apparatus having a planar or non-planar form. The method of claim 1, The antenna is Inductively coupled plasma processing apparatus, which is a planar antenna or a non-planar antenna. The method of claim 1, The antenna is An inductively coupled plasma processing apparatus positioned above the vacuum chamber or located inside a reaction chamber in which the plasma generated in the vacuum chamber is generated. The method of claim 1, The permanent magnet is An inductively coupled plasma processing apparatus arranged in the form of at least one concentric circle, at least one concentric square, and at least one spiral. The method of claim 9, The permanent magnet is At least one of a thickness and a height increases as the distance from the center of the vacuum chamber increases. The method of claim 9, The permanent magnet is An inductively coupled plasma processing apparatus having a narrower distance from a center of the vacuum chamber. The method of claim 1, The permanent magnet is Inductively coupled plasma processing apparatus arranged in the form of any one of a plurality of parallel and at least one serpentine in parallel. The method of claim 1, The magnetic field strength formed in the vertical direction of the vacuum chamber is And a radio frequency applied to the antenna is 0.2 to 10 times the magnetic field strength which is the electron cyclotron frequency. The method of claim 1, The permanent magnet is Inductively coupled plasma processing apparatus that is cylindrical or hexahedral. In the plasma generating method of the inductively coupled plasma processing apparatus, (a) injecting a reaction gas into the upper part of the sample in the low pressure reaction chamber; (b) generating electromagnetic waves with the reaction gas using an antenna supplied with RF power; And (c) The image of the sample to be uniform on the distribution of the plasma generated by the electromagnetic wave, and to be formed on top of the sample. Applying a magnetic field in the vertical direction of the reaction chamber by using a permanent magnet located at the bottom; Plasma generating method comprising a. The method of claim 15, Applying a multipolar surface magnetic field in a direction perpendicular to the axis of the reaction chamber using a plurality of permanent magnets mounted on the side of the reaction chamber; Plasma generating method further comprising. The method of claim 16, And a multipolar surface magnetic field applied in a direction perpendicular to the axis of the reaction chamber by using an electromagnet or a permanent magnet mounted on the side of the reaction chamber. The method of claim 16, And applying a multipolar surface magnetic field in a direction perpendicular to the axis of the reaction chamber by using the plurality of side magnets having opposite polarities of magnets adjacent to each other mounted on the side of the reaction chamber. The method of claim 15, The magnetic field applied in the vertical direction of the reaction chamber Plasma generating method is applied so that the magnetic flux flux density increases as the radially away from the center of the sample.

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