TWI406336B - High-density plasma generator - Google Patents

Abstract

The present invention relates to an inductively coupled high density plasma generating apparatus which stably etches surfaces of sapphire wafers used for producing high luminance LED chips. The apparatus comprises a reaction chamber which provides a space for generating plasma; an antenna system arranged above the reaction chamber to induce electric fields for generating plasma; a dielectric insulation plate interposed between the reaction chamber and the antenna system; and a plurality of permanent magnets arranged along the circumference of the dielectric insulating plate. The plurality of permanent magnets are sequentially arranged in such a manner that one of the magnetic poles of each permanent magnet is the same as one of the magnetic poles of the adjacent permanent magnet and the other of the magnetic poles of each permanent magnet is opposite to the other of the magnetic poles of the adjacent permanent magnet. The antenna system includes a plurality of antenna units arranged in different positions, and each antenna of the antenna units includes a power applying portion to which high frequency power is applied, a ground output portion, and a circular coil. The power applying portion and the ground output portion are arranged to form an opening. The above-described high density plasma generating apparatus can be valuably used in the formation of lens patterns on sapphire wafers, which requires high density plasma etching, as it provides effects of uniform etching using stable plasma.

Description

High density plasma generator

The present invention relates to an inductively coupled high density plasma generator. More particularly, the present invention relates to an inductively coupled high density plasma generator that stably etches the surface of a sapphire wafer used to fabricate high brightness LED wafers.

In general, a plasma generator is classified into a PECVD (plasma-promoted chemical vapor deposition) apparatus for depositing a thin film, an etching apparatus for etching a deposited thin film to pattern a deposited thin film, a sputtering machine, and a ash. Chemical device.

In addition, plasma generators based on RF power application schemes are classified into CCP (Capacitively Coupled Plasma) generators and ICP (Inductively Coupled Plasma) generators. When RF power is applied to the plate electrode, the CCP generator generates plasma by using an RF electric field that is vertically formed between the opposite and parallel plate electrodes, and the ICP generator converts the source by using an induced electric field caused by the transmission antenna. The material is plasmaized to produce a plasma.

This ICP generator has the following structure.

The ICP generator includes a chamber defined as a closed reaction zone, a susceptor disposed thereon to mount the substrate, a gas spray plate for spraying source material from the upper end of the base, and a supply The source material is supplied to a gas supply tube of the gas spray plate.

In order to convert the source material into a plasma, an RF antenna for supplying RF power is provided on the chamber cover. This RF antenna is connected to the RF power source via a feed cable. A matcher is placed in the RF antenna and RF power source Match between load impedance and source impedance.

At the same time, the chamber cover below the RF antenna is made of an insulating material to transmit an induced magnetic field to the chamber. The chamber cover includes an insulating material that reduces capacitive coupling between the antenna and the plasma so that energy can be transferred from the RF power source to the plasma through inductive coupling.

When radio frequency power is supplied to the radio frequency antenna, a time-varying magnetic field in the vertical direction is generated around the radio frequency antenna, and an electric field in the horizontal direction is induced into the chamber due to the time-varying magnetic field. The electrons are accelerated by the induced electric field to collide with the neutral gas, so ions and radicals are generated to perform the etching and deposition process of the substrate. At this time, in order to adjust the ion energy incident on the substrate, bias power is applied to the susceptor in addition to the radio frequency power.

In addition to this, a heater or a cooling passage is provided at the susceptor to adjust the temperature of the substrate, and the remaining gas is discharged to the outside through the discharge port with a vacuum pump.

Hereinafter, a process of using an antenna system having the above structure to generate plasma will be briefly described. When RF power is applied to the antenna system, current flows through the antenna system such that a time varying electric field is generated around the antenna system. Therefore, the induced electric field is generated in the reaction chamber by a time-varying electric field. The electrons are heated by the induced electric field, thus producing a plasma that is inductively coupled to the antenna. Therefore, the plasma etching apparatus can perform a plasma etching process or a plasma deposition process by using ions or radicals generated when electrons in the plasma collide with neutral gas particles. At the same time, if RF power is applied to the chuck by using an additional RF power source, the ion energy incident on the substrate can be controlled. The structure of the antenna system will be described later in detail with reference to FIG.

Such an antenna system is disclosed in Korean Patent Application No. 2000-0102257 (published in September 2009), filed by the applicant of the present invention.

Figure 12 is a perspective view of the antenna system disclosed in the above publication.

The antenna system 150 as shown in Fig. 12 includes four circular coil antennas arranged in a multiple structure. In detail, the antenna system 150 includes a first lower antenna 151 arranged in a first plane (XY plane of FIG. 1) adjacent to an upper portion of the reaction chamber, and a first plane arranged in the first lower antenna 151 a second lower antenna 152 spaced apart from the first lower antenna 151, arranged on a second plane parallel to the first plane and moving upward from the first plane (X'-Y' plane of FIG. 1) The first upper antenna 153 and the second upper antenna 154 are arranged on the second plane in the first upper antenna 153 and spaced apart from the first upper antenna 153.

The four circular coil antennas 151 to 154 are arranged corresponding to the edges of the insulating sheets and connected in parallel to a radio frequency power source 180. The four circular coil antennas 151 to 154 respectively include power input terminals 151a to 154a that receive radio frequency power and ground terminals 151b to 151d that are electrically connected to the ground housing 160.

However, according to the antenna system having the above structure, the power loss may occur due to the distance between the circular coil and the grounded object located outside the reaction chamber, so the plasma density may be remarkably lowered at the edge of the substrate carried on the reaction chamber.

In addition, when the length of the coil used to generate the induced electric field increases due to the large-scale process equipment, the inductance is also increased, so the plasma effect The rate reduction and plasma density are irregularly distributed according to the connection structure between the power supply components and the ground power output components.

The present invention has solved the problems occurring in the prior art, and an object of the present invention is to provide a high-density plasma generator capable of inducing an electric field by using a sapphire wafer for etching a high-brightness LED wafer. The magnetic lines of force based on the configuration of the permanent magnets produce a stable high-density plasma to ensure stability.

Another object of the present invention is to provide a high density plasma generator capable of increasing the efficiency of a coil by limiting the power lost through a chamber wall as a ground in a predetermined region.

Still another object of the present invention is to provide a high-density plasma generator capable of realizing a large-scale process apparatus by using magnetic lines of force based on a configuration of an induced electric field and a permanent magnet.

In order to accomplish the above object, there is provided a high-density plasma generator comprising a reaction chamber having a cavity for generating a plasma, an antenna system provided in an upper portion of the reaction chamber to induce an electric field to generate plasma, and provided in A dielectric insulating plate between the reaction chamber and the antenna system, and a plurality of permanent magnets disposed around the dielectric insulating plate. The permanent magnets are arranged in order such that the same polarity and different polarities are alternately formed between two adjacent permanent magnets. The antenna system includes a plurality of antenna components that are located at positions different from each other. The antenna of each antenna component includes a power receiving component that receives RF power, a ground output component, and a circular coil, and an opening defined by the power receiving component and the grounding output component.

According to the present invention, the permanent magnets are respectively disposed outside the antenna components, and are separated from each other by a distance of about 1 mm to about 15 mm.

According to the present invention, the vertical distance from the horizontal plane of the circular coil to the power receiving component to the grounding output component is from about 100 mm to about 300 mm, and the power receiving component is at a distance of about 15 mm to about 25 mm and grounded The output components are separated to form an opening.

In accordance with the present invention, an antenna assembly includes a first lower antenna aligned with a first plane adjacent an upper portion of the reaction chamber, and a second lower antenna aligned with a first plane within the first lower antenna.

In accordance with the present invention, an antenna assembly includes a first upper antenna aligned parallel to a first plane and moving upwardly from a first plane, and a second upper antenna aligned with a second plane within the first upper antenna.

In accordance with the present invention, an antenna assembly includes a third upper antenna aligned in a third plane parallel to the second plane and moving upward from the second plane, and a fourth upper antenna aligned in a third plane within the third upper antenna.

In accordance with the present invention, the antenna assembly further includes a third lower antenna aligned with a first plane within the second lower antenna.

According to the present invention, an antenna component includes a first upper antenna aligned with a second plane parallel to the first plane and moving upward from the first plane, a second upper antenna aligned with a second plane within the first upper antenna, and an alignment a third upper antenna of the second plane within the upper antenna.

According to the invention, the antenna assembly includes a fourth upper antenna aligned with a third plane that is parallel to the second plane and moves upward from the second plane, alignment a fifth upper antenna of a third plane within the four upper antennas and a sixth upper antenna aligned with a third plane within the fifth upper antenna.

According to the invention, the opening of the first lower antenna and the opening of the second lower antenna are arranged at 180° intervals on the concentric circles of the circular coil.

According to the invention, the opening of the first lower antenna, the opening of the second lower antenna, the opening of the first upper antenna, and the opening of the second upper antenna are arranged at 90° intervals on the concentric circles of the circular coil.

According to the present invention, the opening of the first lower antenna, the opening of the second lower antenna, the opening of the first upper antenna, the opening of the second upper antenna, the opening of the third upper antenna, and the opening of the fourth upper antenna are 60° The spacing is arranged on the concentric circles of the circular coil.

According to the present invention, the opening of the first lower antenna, the opening of the second lower portion, and the opening of the third lower antenna are arranged at 120° intervals on the concentric circles of the circular coil.

According to the present invention, the opening of the first lower antenna, the opening of the second lower antenna, the opening of the third lower antenna, the opening of the first upper antenna, the opening of the second upper antenna, and the opening of the third upper antenna are 60° The spacing is arranged on the concentric circles of the circular coil.

According to the present invention, the opening of the first lower antenna, the opening of the second lower antenna, the opening of the third lower antenna, the opening of the first upper antenna, the opening of the second upper antenna, the opening of the third upper antenna, and the fourth upper portion The opening of the antenna, the opening of the fifth upper antenna, and the opening of the sixth upper antenna are arranged at 40° intervals on the concentric circles of the circular coil.

According to the invention, the vertical distance between the first and second planes is from about 5 mm to about 20 mm.

According to the invention, the vertical distance between the second and third planes is from about 5 mm to about 20 mm.

According to the invention, the circular coil has a diameter of from about 2 mm to about 7 mm and is made of copper, and the surface of the circular coil is silver plated, gold or platinum.

According to the invention, the first and second upper antennas are respectively located on horizontal planes corresponding to the first and second lower antennas.

According to the present invention, the third and fourth upper antennas and the first and second upper antennas are respectively located on horizontal planes corresponding to the first and second lower antennas.

According to the present invention, the first to third upper antennas are respectively located on horizontal planes corresponding to the first to third lower antennas.

According to the present invention, the fourth to sixth upper antennas and the first to third upper antennas are respectively located on horizontal planes corresponding to the first to third lower antennas.

As described above, according to the high-density plasma generator of the present invention, when the lens pattern is formed on a sapphire wafer through a plasma etching process to manufacture an LED, a uniform etching effect can be obtained due to stable plasma.

In addition, according to the present invention, the plasma flux lost through the chamber wall can be defined in a predetermined region by pushing the plasma flux toward the substrate carried in the reaction chamber, so that the plasma density can be uniformly distributed. The entire area of the substrate.

Further, according to the present invention, loss through the wall of the chamber as a ground The power can be limited to a predetermined area due to the configuration of the permanent magnet, so the efficiency of the coil can be improved. Therefore, the process equipment can be manufactured in a large size by automatic division, so the yield can be improved.

In addition to this, according to the present invention, the coil is made of round copper having a diameter of about 2 mm to about 7 mm, and silver, gold or platinum is plated on the surface of the coil, so power transmission efficiency can be improved. And the plasma efficiency can be increased by cooling the heat generated by the antenna.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings.

First, the concept of the present invention will be described.

In accordance with the present invention, an antenna system includes a plurality of circular coils aligned parallel to each other, wherein each circular coil is provided with a power supply component and a ground output component (ground component) and a power ground component and a The ground defines the opening defined by the component. In order to compensate for the plasma uniformity of the circular antenna having an opening, the circular antenna includes an inner circular coil and an outer circular coil such that the openings of the inner and outer coils are symmetrical to each other at an angle of 180°. Therefore, the plasma discharged by the plasma is not biased in one direction.

The antenna assembly of the antenna system used in the present invention includes an inner circular coil having an opening and an outer circular coil having an opening. This antenna component has a loop-type antenna structure in which current flows in the same direction. A single coil that generates an induced electric field is provided with a power receiving component and a grounding component to form an opening therebetween, so that plasma unevenness in this partial region may increase. In the case of a multi-layer structure, arranged A pair of coils having openings separates the openings from each other at an angle of 90 to compensate for the power modulation of the circular antenna with power receiving components and ground output components, thus ensuring stable plasma uniformity.

To compensate for the non-uniformity of the plasma that occurs in a localized region between the power receiving component and the grounded output component, both ends of the reference coil are vertically upwardly curved. If a plurality of layers are formed by the above-described manner, plasma non-uniformity occurring in a local region between the power receiving component of the coil generating the induced electric field and the ground output component of the coil can be prevented. That is to say, in terms of structure, when viewed from the perspective of the substrate carried in the chamber, the coil is considered to provide two coils on a flat dielectric insulating plate, thereby preventing induction from a plurality of induction coils. The decrease in plasma discharge efficiency caused by the coefficient.

In this way, the loop type antenna whose current flows in the same direction can be made into a three-layer structure or a four-layer structure. The three-layer coils are arranged to rotate at an angle of 60°, thereby compensating for power modulation in a region of the circular antenna having an opening to ensure stable plasma uniformity.

The non-uniformity of the plasma density may locally occur in the area of the circular antenna with the opening due to the power receiving component of the discharge current and the ground output component. In order to solve the above problem, the openings are formed in an antenna having a two-layer structure or a three-layer structure such that the openings are spaced apart from each other by an angle of 60 or 90, thereby reducing the unevenness of the plasma density in the partial regions.

If an antenna component including an internal coil and an external coil and RF power is applied to a circular coil, the plasma is caused by an induced magnetic field applied to the coil. The density can vary depending on the diameter of the inner coil based on the substrate carried in the reaction chamber, and the outer coil can compensate for plasma uniformity. Because of the power loss caused by the distance between the circular coil and the external grounded object, the plasma density may be significantly reduced at the edge of the substrate carried in the reaction chamber. To solve this problem, the permanent magnets are arranged to push the plasma flux toward the substrate carried in the reaction chamber, and the plasma flux lost through the chamber wall in this manner can be limited to a predetermined area. Therefore, the plasma density can be uniformly distributed over the entire area of the substrate.

A power receiving component can be divided into a plurality of power receiving components connected in parallel with one another in order to simultaneously etch a plurality of substrates in a plasma vacuum chamber by using a plurality of separate dielectric insulating plates. When the length of the coil for generating the induced electric field is increased due to the large-sized process equipment, the inductance is also increased, so the plasma efficiency is reduced. In order to solve this problem, the permanent magnets are arranged such that the coil is subjected to the magnetic field, and the power loss through the wall of the chamber as the ground is limited to a predetermined area, so that the coil efficiency can be improved and the process apparatus can be enlarged by automatic division. Size manufacturing.

According to the related art, wherein the coil includes a spiral coil and a double circular coil to generate an induced electric field, an electromagnetic coil fabricated in the form of a spiral coil is provided outside the chamber to compensate for a low plasma density at the edge of the substrate, The structure of the device is complex and power control is difficult. As for a helical antenna including a plurality of spiral coils that are separated and flattened to each other, even if the spiral coils have the same current direction, the magnetic fields formed around the spiral coils can be reinforced or canceled by each other due to the spiral coils, so The plasma density of the edge of the substrate carried in the reaction chamber can be Can be reduced. To this end, an electromagnetic coil such as a spiral coil must be provided to increase the uniformity of the plasma density distribution.

The present invention has solved the above-described problems of the antennas occurring in the related art. In accordance with the present invention, the power receiving components and grounding output components are arranged to face each other with respect to the substrate carried in the reaction chamber. In addition to this, the power receiving component can be divided into a plurality of power receiving components arranged in parallel with each other according to process conditions, and the coil can generate induced electric fields parallel to each other in this way, thus generating plasma. At this time, the vertical distance from the power receiving component of a circular coil to the horizontal plane of the other circular coil closest to the circular coil is at least 100 mm to 300 mm. In this case, the unevenness of the plasma density distribution caused by the architecture of the power receiving component and the grounding output component can be solved.

This coil can be fabricated by using round copper having a diameter of from about 2 mm to about 7 mm. To improve power transfer efficiency, the coil is silver plated, gold or platinum. This coil has a function of cooling the heat generated therefrom.

A single layer coil includes an inner circular coil and an outer circular coil. When the substrate has been processed, the diameter of the inner circular coil and the outer circular coil can be determined according to the uniformity caused by the substrate carried in the reaction chamber. In addition to this, in order to compensate for the unevenness at the edge of the substrate according to the plasma distribution, the configuration of the permanent magnet can be adjusted.

When the process time is shortened, the coil may have a multilayer structure in order to increase the plasma density. If the coil has a multilayer structure, the uniformity of plasma distribution can be improved compared to a coil having a single layer structure. Multilayer structure The coils are arranged similarly to the coils having a single layer structure except that they are separated from each other by 5 mm to 20 mm in the longitudinal direction. At this time, in order to reduce the influence of the capacitance component caused by the diameter of the circular coil, the two coils are vertically spaced or angularly arranged with respect to the substrate, thereby improving the uniformity of the plasma density distribution to achieve the reinforcing effect.

In order to reduce the potential difference caused by the influence of a plurality of capacitor components having a plurality of layers of coils, the diameter of the coil may vary with a reference coil. In this case, the effect of the capacitive component can be minimized.

According to the related art, at least one variable capacitor is provided between the coil including the circular coil and the spiral coil to adjust the current, thus forming a plurality of loop type antennas.

However, according to the present invention, the permanent magnets are arranged differently to obtain magnetic lines of force having different shapes and strengths. The permanent magnets are circularly arranged to be spaced apart from the circular antenna coil, wherein the distance between two adjacent permanent magnets is from 1 mm to 15 mm, and the magnetic poles may be alternately formed in this manner. In addition to this, the permanent magnets are arranged circularly such that the magnetic field can have a minimum Gauss value at a predetermined distance from the edge of the substrate carried by the reaction chamber. If the process is performed while the plasma density is generated by the induced electric field, the magnetic force may not affect the process. In detail, since the process parameters from the magnetic lines of force can be removed during the process, the power lost through the chamber walls can be limited to the process area, so the uniformity of the plasma density can be improved. That is to say, the uniformity of the plasma density can be improved due to the structure of the coil and the configuration of the magnetic poles.

The plasma produced under the above conditions can be lower than the conventional plasma process pressure Stable discharge under pressure. If the present invention is applied to a process for etching the surface of a sapphire wafer for manufacturing an LED, a uniform plasma density distribution can be obtained under a process pressure of several mT to several hundred mT, so the etched crystal of the sapphire used in the manufacture of the LED of the present invention is etched. The circle is very effective.

<Example 1>

Hereinafter, a first embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The present invention provides an ICP (Inductively Coupled Plasma) generator for etching wafer surfaces used to fabricate high brightness LED wafers.

1 is a perspective view showing the structure of a high-density plasma generator according to a first embodiment of the present invention, and FIG. 2 is a view showing an antenna system 150 and a permanent magnet 190 as shown in FIG. A plan view of the interposed configuration relationship, and Fig. 3 is a plan view showing the effective magnetic force distribution based on the configuration of the permanent magnet according to the present invention.

Referring to Fig. 1, a high-density plasma generator 100 according to the present invention includes a reaction chamber 110 having a cavity for generating plasma, and a substrate tray 120 containing a plurality of substrates subjected to a plasma etching process, provided in the reaction chamber. The lower inner portion of 110 is a wafer holder 130 supporting the substrate tray 120, an antenna system 150 providing an electric field at the upper portion of the reaction chamber to induce plasma generation, and a dielectric insulating plate interposed between the reaction chamber 110 and the antenna system 150. 140. A grounded housing 160 provided at an upper portion of the antenna system 150, an RF power source 170 for supplying RF power to the antenna system 150, and an impedance matching device for matching the internal impedance of the RF power source 170 with the impedance of the RF supply path. 180, and a plurality of arranged around the dielectric insulating plate 140 Permanent magnet 190.

The reaction chamber 110 has a cylindrical shape and is composed of a cavity that generates plasma for etching the substrate. The reaction chamber 110 is provided on a side wall having a gas feed port 114 for supplying process gas into the reaction chamber 110 and a recess 111 for guiding the substrate tray 120 into the cavity 112 of the reaction chamber 110.

The wafer holder 110 is provided at a lower portion of the cavity 112 of the reaction chamber 110 to support the substrate tray 120. Wafer mount 130 can provide biased RF power to allow plasma generated in reaction chamber 110 to collide with the surface of the substrate. In this case, the wafer holder 130 is electrically coupled to an additional source of RF power that is different from the RF power source 170 that supplies the RF power to the antenna system 150 as an RF electrode.

The antenna system 150 has a coil structure and receives radio frequency power from the RF power source 170 to induce a magnetic field in the reaction chamber 110 to generate plasma in the reaction chamber 110. The first figure shows the antenna configuration provided in the antenna system 150 in the form of a coil.

Hereinafter, a process for generating a plasma by using the antenna system 150 will be briefly described. When radio frequency power is applied to the antenna system 150, current flows through the antenna system 150 such that a time varying magnetic field is generated around the antenna system 150. At this time, the variable magnetic field forms an induced electric field in the reaction chamber 110 and the electrode is heated by the induced electric field, thereby generating a plasma inductively coupled to the antenna. The plasma generator 100 can perform a plasma etching process or a plasma deposition process by using ions or radicals generated when electrons in the plasma collide with neutral gas particles. At the same time, if RF power is applied to the wafer holder 130 from an additional RF power source, the ion energy incident on the substrate can be controlled. Antenna system The detailed structure of 150 will be described in detail later.

Meanwhile, as described above, the induced electric field is formed around the antenna system by the radio frequency power supplied from the RF power source 170, and the positive and negative charges are alternately charged on the surface of the antenna system 150 at a high frequency, so that a capacitance is generated. Electric field. However, although the capacitive electric field can promote the initial plasma discharge in the ICP generator, this capacitive electric field may destroy the dielectric material disposed between the plasma and the antenna system 150 due to sputtering, such that plasma uniformity may occur. decline.

The dielectric insulating plate 140 is provided to prevent adverse effects of the capacitive electric field. The dielectric insulating plate 140 is disposed between the reaction chamber 110 and the antenna system 150 to reduce the capacitive electric field and efficiently transmit the induced electric field to the plasma. In detail, the dielectric insulating plate 140 reduces the capacitive coupling between the antenna system 150 and the plasma so that the energy of the RF power source 170 can be efficiently transferred to the plasma through inductive coupling. The dielectric insulating plate 140 has a disk shape and is made of ceramic. Therefore, this dielectric insulating plate 140 is referred to as a "Faraday shield" or a "ceramic window." The dielectric insulating plate 140 is supported by the lower flange 162 of the grounded housing 160 and fixed by the fixed base 163.

The grounded housing 160 is a cylindrical metal housing and is provided in an upper portion of the antenna system 150 to prevent the antenna system 150 from being exposed to the outside. This grounded housing 160 provides a grounded area that is electrically coupled to the ground terminal of the antenna assembly of the antenna system 150.

Although not shown in Fig. 1, the plasma generator 100 further includes a vacuum pump that causes the reaction chamber 100 to be in a vacuum state, and is formed in the reaction chamber. 110 is to discharge a gas discharge port of a gas generated in the reaction chamber 110 via a plasma reaction.

In the following, the configuration of the antenna components and permanent magnets provided in the antenna system 150 will be described with reference to Figs. 1 to 3.

According to a first embodiment, antenna system 150 includes an antenna component having a pair of single layer coils. As shown in FIGS. 1 and 2, the antenna component 10 according to the first embodiment includes a first lower antenna 11 aligned with a first plane adjacent to an upper portion of the reaction chamber 110, and is disposed on a first plane. The second lower antenna 12 in the first lower antenna 11 is. Each antenna includes a power receiving component 18 coupled to a radio frequency power source 170 for receiving radio frequency power, a ground output component 19 coupled to the grounded housing 160, and a circular coil, wherein the opening 17 is defined in the power receiving component 18 and Ground output between components 19.

In detail, the antenna component 10 according to the first embodiment includes a pair of circular antennas, wherein each antenna includes a power receiving component 18 and a grounding output component 19. In order to improve the plasma uniformity of the circular antenna having the opening 17, the circular antenna is provided with an inner circular coil and an outer circular coil, and the opening of the inner circular coil is symmetrical to the outer circular coil at an angle of 180°. The opening, the plasma discharged through the plasma in this way may not be biased in one direction. The first lower antenna 11 having an opening and the second lower antenna 12 having an opening may constitute a loop type antenna in which current flows in the same direction. A single coil that produces an induced electric field can include a power receiving component 18 and a ground output component 19 in such a manner that the opening 17 is formed between the power receiving component 18 and the grounding output component 19. Therefore, the unevenness of the plasma in this partial region may increase. For understanding To solve this problem, as shown in Figure 2, the antenna assembly includes two open components. In detail, the openings of the first lower antenna 11 are arranged at positions where the opening of the second lower antenna 12 is rotated by an angle of 180°.

In addition, the vertical distance l from the horizontal plane of the circular coil of the first lower antenna 11 to the power receiving component 18 and the ground output component 19 is from about 100 mm to about 300 mm, and the power receiving component 18 is The opening 19 is formed relative to the ground output member 19 at a distance of from about 15 mm to about 25 mm. If the distance between the power receiving component 18 and the ground output component 19 is within 10 millimeters, the plasma density is biased in one direction. Conversely, if the distance between the power receiving component 18 and the ground output component 19 exceeds 30 millimeters, the plasma density is symmetrically curved.

Therefore, when RF power is applied to the circular coil, the plasma density generated by the induced magnetic field applied to the coil may vary depending on the diameter of the internal coil based on the substrate carried in the reaction chamber 110, and the external coil may be Make up for plasma uniformity. However, according to the above structure, the power loss may occur due to the distance between the circular coil and the grounded object located outside the reaction chamber 110, so the plasma density at the edge of the substrate carried in the reaction chamber 110 may be remarkably reduce. In order to compensate for the decrease in plasma density, the permanent magnets 190 are arranged to push the plasma flux toward the substrate carried in the reaction chamber 110, in such a manner that the plasma flux lost through the chamber wall 111 can be limited to a predetermined within the area. Therefore, the plasma density can be uniformly distributed over the entire area of the substrate.

In addition, a power receiving component can be divided into a plurality of power receiving components connected in parallel with each other, in order to use a plurality of separate powers. The dielectric insulation plate simultaneously etches a plurality of substrates in the plasma vacuum chamber 110. When the length of the coil for generating the induced electric field is increased due to the large-sized process equipment, the inductance is also increased, so the plasma efficiency is reduced. In order to solve this problem, the permanent magnets 190 are arranged such that the coils are subjected to the magnetic field, and the power loss through the chamber wall 111 as the ground is limited to a predetermined area, so that the coil efficiency can be improved and the process equipment can be automatically divided. Made in large size.

The coil of antenna assembly 10 is made of round copper having a diameter of from about 2 mm to about 7 mm, and silver, gold or platinum is plated on the surface of the coil to improve power transfer efficiency and cooling from antenna assembly 10 The heat generated.

The permanent magnets 190 used in the present invention are arranged differently to obtain magnetic lines of force having different shapes and strengths. In detail, the permanent magnets are circularly arranged to be spaced apart from the circular antenna coil, wherein the distance between two adjacent permanent magnets 190 is 1 mm to 15 mm, and the magnetic poles may be alternately formed in this manner. In addition, the permanent magnets 190 are circularly arranged such that the magnetic field can have a minimum Gauss value at a predetermined distance from the edge of the substrate carried by the reaction chamber. If the process is performed while the plasma density is generated by the induced electric field, the magnetic force may not affect the process. Therefore, the process parameters from the magnetic lines of force can be removed during the process, so the power lost through the chamber wall 111 can be limited to the process area, so the uniformity of the plasma density can be improved. That is to say, the uniformity of the plasma density can be improved due to the structure of the coil and the configuration of the magnetic poles.

The permanent magnet 190 is disposed outside of the antenna assembly 10 and the number of permanent magnets 190 may depend on the outer diameter or permanent of the dielectric insulating plate 140. The size or magnetic force of the magnet 190 changes. In this regard, the invention does not limit the number and size of permanent magnets 190.

The distance d between two adjacent permanent magnets 190 is set to be 1 mm to 15 mm, and the permanent magnets 190 are sequentially arranged such that the same polarity and different polarities are alternately formed in two adjacent permanent Between the magnets 190. Therefore, the effective magnetic force distribution as shown in Fig. 3 can be obtained.

As described above, according to the first embodiment of the present invention, as shown in FIG. 3, the limit line of the effective magnetic force distribution is provided, so that the plasma process area can be extended beyond the outer diameter of the substrate W, so the process efficiency can be raised.

<Example 2>

Hereinafter, a second embodiment of the present invention will be described with reference to FIG.

Fig. 4 is a plan view showing the configuration of an antenna component according to a second embodiment of the present invention.

The structure according to the second embodiment is similar to the structure according to the first embodiment except for the structure of the antenna component of the antenna system 150. Therefore, to avoid redundancy, the following description will focus on the structure of the antenna component 20.

According to the second embodiment of the present invention, the antenna component 20 has a two-layer structure similar to the related art. In detail, the antenna component 20 according to the second embodiment of the present invention includes a first lower antenna arranged in a first plane adjacent to an upper portion of the reaction chamber 110, and a first array arranged in the first lower antenna a second lower antenna spaced apart from the first lower antenna on a plane, and a second flat arranged parallel to the first plane and moving upward from the first plane a first upper antenna on the face and a second upper antenna spaced apart from the first upper antenna on a second plane within the first upper antenna.

Therefore, as shown in FIG. 4, the antenna component 20 according to the second embodiment of the present invention includes four openings, that is, an opening of the first lower antenna, an opening of the second lower antenna, and a first upper antenna. The opening and the opening of the second upper antenna are arranged at 90° intervals on the concentric circles of the circular coil.

At the same time, the vertical distance between the first and second planes is from about 5 mm to about 20 mm. That is, according to the second embodiment of the present invention, a coil having a two-layer structure is provided to increase the plasma density and shorten the process time. This two-layer structure can increase the plasma density compared to a single layer structure. At this time, the vertical distance between two adjacent antennas is about 5 mm to about 20 mm. In addition, in order to reduce the influence of the capacitance component caused by the diameter of the circular coil, the two coils are vertically spaced or angularly arranged with respect to the substrate, thereby improving the uniformity of the plasma density distribution and enhancing effect.

In order to reduce the potential difference caused by the influence of a plurality of capacitor components having a plurality of layers of coils, the diameter of the coil may vary with a reference coil. In this case, the effect of the capacitive component can be minimized.

That is, if the antenna component 20 has the above-described two-layer structure, the plasma density distribution can be uniformly formed over the entire area of the substrate.

<Example 3>

Hereinafter, a third embodiment of the present invention will be described with reference to FIG.

Fig. 5 is a plan view showing the configuration of an antenna component according to a third embodiment of the present invention.

The structure according to the third embodiment is similar to the structure according to the first embodiment except for the structure of the antenna component of the antenna system 150. Therefore, to avoid redundancy, the following description will focus on the structure of the antenna component 30.

According to the third embodiment of the present invention, the antenna component 30 has a three-layer structure. In detail, the antenna component 30 according to the third embodiment of the present invention includes a first lower antenna arranged in a first plane adjacent to an upper portion of the reaction chamber 110, and a first array arranged in the first lower antenna a second lower antenna spaced apart from the first lower antenna on a plane, a first upper antenna arranged on a second plane parallel to the first plane and moving upward from the first plane, arranged in the first upper antenna a second upper antenna spaced apart from the first upper antenna on the second plane, a third upper antenna arranged on a third plane parallel to the second plane and moving upward from the second plane, and arranged in the third upper portion a fourth upper antenna spaced apart from the third upper antenna in a second plane within the antenna.

Therefore, as shown in FIG. 5, the antenna component 30 according to the third embodiment of the present invention includes six openings, wherein the opening of the first lower antenna, the opening of the second lower antenna, and the opening of the third upper antenna They are arranged on the concentric circles of the circular coil at intervals of 60°.

If the antenna component 30 has the above-described three-layer structure, the plasma density distribution can be uniformly formed over the entire area of the substrate as compared with the second embodiment of the present invention.

If a plurality of layers are formed by the above-described manner, plasma non-uniformity occurring in a local region between the power receiving component of the coil generating the induced electric field and the ground output component of the coil can be prevented. That is to say, in terms of structure, when viewed from the perspective of the substrate carried in the chamber, the coil is considered to provide two coils on a flat dielectric insulating plate, thereby preventing induction from a plurality of induction coils. The decrease in plasma discharge efficiency caused by the coefficient.

<Example 4>

Hereinafter, a fourth embodiment of the present invention will be described with reference to FIG.

Fig. 6 is a plan view showing the configuration of an antenna component according to a fourth embodiment of the present invention.

The structure according to the fourth embodiment is similar to the structure according to the first embodiment except for the structure of the antenna component of the antenna system 150. Therefore, to avoid redundancy, the following description will focus on the structure of the antenna component 40.

According to a fourth embodiment of the invention, antenna component 40 includes three separate antennas. In detail, the antenna component 40 according to the fourth embodiment of the present invention includes a first lower antenna arranged in a first plane adjacent to an upper portion of the reaction chamber 110, and a first array arranged in the first lower antenna a second lower antenna spaced apart from the first lower antenna on a plane, and a third lower antenna spaced on the first plane in the second lower antenna and spaced apart from the second lower antenna.

Therefore, as shown in FIG. 6, the antenna component 40 according to the fourth embodiment of the present invention includes three openings, wherein the opening of the first lower antenna, the second The opening of the lower antenna and the opening of the third lower antenna are arranged at 120° intervals on the concentric circles of the circular coil.

If the antenna component 40 has the above three separate antennas, the plasma density distribution can be uniformly formed over the entire area of the substrate as compared with the first embodiment of the present invention.

<Example 5>

Hereinafter, a fifth embodiment of the present invention will be described with reference to FIGS. 7 to 9.

Figure 7 is a plan view showing the configuration of an antenna component according to a fifth embodiment of the present invention, and Figures 8a and 8b are diagrams for explaining the difference between the single-layer structure and the multilayer structure of the antenna component. The photographic images of the experimental results, and the 9a and 9b graphs are graphs showing the measurement results of the substrate uniformity when the antenna component has a single layer structure and a three layer structure.

The structure according to the fifth embodiment is similar to the structure according to the first embodiment except for the structure of the antenna component of the antenna system 150. Therefore, to avoid redundancy, the following description will focus on the structure of the antenna component 50.

According to a fifth embodiment of the present invention, the antenna component 50 includes a first lower antenna arranged on a first plane adjacent to an upper portion of the reaction chamber 110, arranged on a first plane within the first lower antenna a second lower antenna spaced apart from the first lower antenna, a first upper antenna arranged on a second plane parallel to the first plane and moving upward from the first plane, and a second array arranged in the first upper antenna a second upper antenna spaced apart from the first upper antenna in a plane, arranged parallel to the second plane and extending from the second plane a third upper antenna on the third plane that moves upward, and a fourth upper antenna that is arranged on the second plane in the third upper antenna and spaced apart from the third upper antenna.

Therefore, as shown in FIG. 7, the antenna component 50 according to the fifth embodiment of the present invention includes six openings, wherein the opening of the first lower antenna, the opening of the second lower antenna, the opening of the first upper antenna, The opening of the second upper antenna, the opening of the third upper antenna, and the opening of the fourth upper antenna are arranged at 60° intervals on the concentric circles of the circular coil.

The vertical distance between the first and second planes is from about 5 mm to about 20 mm. That is, according to the fifth embodiment of the present invention, a coil having a multilayer structure is provided to increase the plasma density and shorten the process time. This multilayer structure can increase the plasma density compared to a single layer structure. At this time, the vertical distance between two adjacent antennas is about 5 mm to about 20 mm. In addition, in order to reduce the influence of the capacitance component caused by the diameter of the circular coil, the two coils are vertically spaced or angularly arranged with respect to the substrate, thereby improving the uniformity of the plasma density distribution and enhancing effect.

That is, as can be seen from Fig. 8, if the antenna component 50 has the above-described three-layer structure, the plasma density distribution can be uniformly formed over the entire area of the substrate as compared with the single-layer structure.

As can be seen from the experimental results shown in Fig. 9, if the antenna component has a single layer structure, the etching depth in the center direction of the substrate is narrowed, so the uniformity of the substrate is lowered. However, if the antenna component has a multilayer structure, the etching depth over the entire area of the substrate is uniform.

<Example 6>

Hereinafter, a sixth embodiment of the present invention will be described with reference to FIG.

Fig. 10 is a plan view showing the configuration of an antenna component according to a sixth embodiment of the present invention.

The structure according to the sixth embodiment is similar to the structure according to the first embodiment except for the structure of the antenna component of the antenna system 150. Therefore, to avoid redundancy, the following description will focus on the structure of the antenna component 60.

According to a sixth embodiment of the present invention, the antenna component 60 includes a first lower antenna arranged on a first plane adjacent to an upper portion of the reaction chamber 110, arranged on a first plane within the first lower antenna And a second lower antenna spaced apart from the first lower antenna, a third lower antenna arranged on the first plane in the second lower antenna and spaced apart from the second lower antenna, arranged parallel to the first plane and a first upper antenna on a second plane in which the first plane moves upward, a second upper antenna arranged on a second plane in the first upper antenna and spaced apart from the first upper antenna, and arranged in the second upper antenna a third upper antenna spaced apart from the second upper antenna on the second plane, a fourth upper antenna arranged on a third plane parallel to the second plane and moving upward from the second plane, arranged in the fourth upper antenna a fifth upper antenna spaced apart from the fourth upper antenna on the third plane, and a sixth upper antenna spaced apart from the fifth upper antenna in a third plane disposed within the fifth upper antenna.

According to a sixth embodiment, the vertical distance between the first and second planes is from about 5 mm to about 20 mm, and the vertical distance between the second and third planes is from about 5 mm to about 20 mm.

Therefore, as shown in FIG. 10, the antenna component 60 according to the sixth embodiment of the present invention includes nine openings, wherein the opening of the first lower antenna, the opening of the second lower antenna, the opening of the third lower antenna, The opening of the first upper antenna, the opening of the second upper antenna, the opening of the third upper antenna, the opening of the fourth upper antenna, the opening of the fifth upper antenna, and the opening of the sixth upper antenna are arranged at intervals of 40°. On the concentric circles of the circular coil.

The plasma produced under the above conditions can be stably discharged at a pressure lower than that of the conventional plasma process. If the present invention is applied to the surface of a sapphire wafer for etching LEDs, a uniform plasma density distribution can be obtained at a process pressure of several mT to several hundred mT, so the present invention etches a sapphire wafer for manufacturing LEDs. It is very effective.

In detail, as can be seen from Fig. 11, condition 2 (such as the antenna structure shown in Fig. 7) exhibits a higher etching depth uniformity than condition 1 (such as the antenna structure shown in Fig. 4). That is, the uniformity of the plasma density of Condition 1 is higher than Condition 2. Except for this, the etching depth of Condition 2 is deeper than Condition 1, which means that the uniformity of the plasma density of Condition 1 is higher than Condition 2.

According to the present invention, the first and second lower antennas are respectively located at positions spaced apart from the center of the circular coil by 300 mm and 200 mm, and the first to third lower antennas of the three separate antennas are respectively located The center of the circular coil is separated by 340 mm, 280 mm and 160 mm. However, the present invention is not limited thereto, and the positions of the first to third antennas may vary depending on the volume of the reaction chamber.

Although an exemplary embodiment of the present invention has been described, it should be understood that the present invention The present invention is not limited to the exemplary embodiments, and various changes and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention as set forth in the appended claims.

10, 20, 30, 40, 50, 60‧‧‧ antenna components

100‧‧‧High-density plasma generator

11‧‧‧First lower antenna

110‧‧‧Reaction room

111‧‧‧ chamber wall

112‧‧‧ Cavity

114‧‧‧ gas inlet

12‧‧‧Second lower antenna

120‧‧‧ substrate plate

130‧‧‧ Wafer Holder

140‧‧‧Dielectric insulation board

150‧‧‧Antenna system

160‧‧‧ Grounding enclosure

162‧‧‧Flange

163‧‧‧Fixed pedestal

17‧‧‧ openings

170‧‧‧RF power source

18‧‧‧Power receiving components

180‧‧‧impedance matcher

19‧‧‧ Grounding output components

190‧‧‧Permanent magnet

D‧‧‧distance

l ‧‧‧vertical distance

1 is a perspective view showing the structure of a high-density plasma generator according to a first embodiment of the present invention; and FIG. 2 is a view showing the relationship between the antenna system and the permanent magnet as shown in FIG. A plan view of the configuration relationship; FIG. 3 is a plan view showing an effective magnetic force distribution based on the configuration of the permanent magnet according to the present invention; and FIG. 4 is a view showing the configuration of the antenna component according to the second embodiment of the present invention. FIG. 5 is a plan view showing a configuration of an antenna component according to a third embodiment of the present invention; and FIG. 6 is a plan view showing a configuration of an antenna component according to a fourth embodiment of the present invention; 7 is a plan view showing a configuration of an antenna component according to a fifth embodiment of the present invention; FIGS. 8a and 8b are diagrams for explaining a difference between a single layer structure and a multilayer structure of an antenna component. Photographs of experimental results; Figures 9a and 9b are graphs showing measurement results of substrate uniformity when the antenna component has a single layer structure and a three layer structure; and Fig. 10 is a view showing a sixth embodiment according to the present invention. Disposing a plan view of the antenna components; FIG. 11a to 11c based on the display as a measurement result of FIG. 4 and the antenna structure shown in Fig. 7; and Fig. 12 is a perspective view showing the structure of an antenna system according to the related art.

10‧‧‧Antenna components

100‧‧‧High-density plasma generator

11‧‧‧First lower antenna

110‧‧‧Reaction room

111‧‧‧ chamber wall

112‧‧‧ Cavity

114‧‧‧ gas inlet

12‧‧‧Second lower antenna

120‧‧‧ substrate plate

140‧‧‧Dielectric insulation board

150‧‧‧Antenna system

160‧‧‧ Grounding enclosure

162‧‧‧Flange

163‧‧‧Fixed pedestal

170‧‧‧RF power source

18‧‧‧Power receiving components

180‧‧‧impedance matcher

19‧‧‧ Grounding output components

190‧‧‧Permanent magnet

l ‧‧‧vertical distance

Claims (22)

A high-density plasma generator comprising: a reaction chamber having a cavity for generating plasma; an antenna system provided in an upper portion of the reaction chamber to generate an electric field to generate the plasma; a dielectric insulation a plate is provided between the reaction chamber and the antenna system; and a plurality of permanent magnets are disposed around the dielectric insulating plate; wherein the permanent magnets are arranged in order such that the same polarity and different polarities are alternately formed Between two adjacent permanent magnets; the antenna system includes a plurality of antenna components positioned at different positions from each other; an antenna of each antenna component includes a power receiving component that receives RF power, and a ground output A component, and a circular coil; and an opening defined by the power receiving component and the grounding output component. The high-density plasma generator of claim 1, wherein the permanent magnets are respectively disposed outside the antenna components and separated from each other by a distance of about 1 mm to about 15 mm. The high density plasma generator of claim 2, wherein a vertical distance from the horizontal plane of the circular coil to the power receiving component and the grounding output component is from about 100 mm to about 300 mm. And the power receiving component is separated from the ground output component by a distance of between about 15 mm and about 25 mm to form the opening. A high-density plasma generator as described in claim 2, wherein the The antenna assembly includes a first lower antenna aligned with a first plane adjacent the upper portion of the reaction chamber, and a second lower antenna aligned with the first plane within the first lower antenna. The high density plasma generator of claim 4, wherein the antenna component comprises a first upper antenna aligned with a second plane parallel to the first plane and moving upward from the first plane, And a second upper antenna that is aligned with the second plane within the first upper antenna. The high-density plasma generator of claim 5, wherein the antenna component comprises a third upper antenna aligned with a third plane parallel to the second plane and moving upward from the second plane, And a fourth upper antenna aligned with the third plane in the third upper antenna. The high density plasma generator of claim 4, wherein the antenna component further comprises a third lower antenna aligned with the first plane in the second lower antenna. The high-density plasma generator of claim 7, wherein the antenna component comprises a first upper antenna aligned with a second plane parallel to the first plane and moving upward from the first plane, Aligning a second upper antenna of the second plane in the first upper antenna and a third upper antenna aligning the second plane in the second upper antenna. The high-density plasma generator of claim 8, wherein the antenna component comprises a fourth upper antenna aligned with a third plane parallel to the second plane and moving upward from the second plane, And aligning a fifth upper antenna of the third plane in the fourth upper antenna, and a sixth upper antenna aligning the third plane in the fifth upper antenna. The high-density plasma generator of claim 4, wherein the opening of the first lower antenna and the opening of the second lower antenna are The 180° spacing is arranged on the concentric circles of the circular coil. The high-density plasma generator of claim 5, wherein the opening of the first lower antenna, the opening of the second lower antenna, the opening of the first upper antenna, and the second upper portion The openings of the antenna are arranged at 90[deg.] intervals on the concentric circles of the circular coil. The high-density plasma generator of claim 6, wherein the opening of the first lower antenna, the opening of the second lower antenna, the opening of the first upper antenna, the second upper portion The opening of the antenna, the opening of the third upper antenna, and the opening of the fourth upper antenna are arranged at a 60° interval on a concentric circle of the circular coil. The high-density plasma generator of claim 7, wherein the opening of the first lower antenna, the opening of the second lower antenna, and the opening of the third lower antenna are 120° The spacing is arranged on the concentric circles of the circular coil. The high-density plasma generator of claim 8, wherein the opening of the first lower antenna, the opening of the second lower antenna, the opening of the third lower antenna, the first upper portion The opening of the antenna, the opening of the second upper antenna, and the opening of the third upper antenna are arranged at a 60° interval on a concentric circle of the circular coil. The high-density plasma generator of claim 9, wherein the opening of the first lower antenna, the opening of the second lower antenna, the opening of the third lower antenna, the first upper portion The opening of the antenna, the opening of the second upper antenna, the opening of the third upper antenna, the opening of the fourth upper antenna, the opening of the fifth upper antenna, and the opening of the sixth upper antenna They are arranged on the concentric circles of the circular coil at intervals of 40°. The high density plasma generator of claim 5, wherein a vertical distance between the first plane and the second plane is from about 5 mm to about 20 mm. The high density plasma generator of claim 6 or 9, wherein a vertical distance from the second plane to the third plane is from about 5 mm to about 20 mm. The high-density plasma generator according to any one of claims 1 to 9, wherein the circular coil has a diameter of about 2 mm to about 7 mm and is made of copper, and the circle One surface of the coil is silver plated, gold or platinum. The high-density plasma generator of claim 11, wherein the first upper antenna and the second upper antenna are respectively located on a horizontal surface corresponding to the first lower antenna and the second lower antenna. . The high-density plasma generator of claim 12, wherein the third upper antenna and the fourth upper antenna and the first upper antenna and the second upper antenna are respectively located corresponding to the first The antenna is on a horizontal plane of the second lower antenna. The high-density plasma generator of claim 14, wherein the first upper antenna to the third upper antenna are respectively located on a horizontal surface corresponding to the first lower antenna to the third lower antenna. . The high-density plasma generator of claim 15, wherein the fourth upper antenna to the sixth upper antenna and the first upper antenna to the third upper antenna respectively correspond to the first The antenna is on a horizontal plane of the third lower antenna.