KR20220023652A - Neutral particle generator with ECR plasma generator - Google Patents

Abstract

A neutral particle generator including an ECR plasma generator according to an embodiment of the present invention includes: a pair of waveguides formed in a tubular shape on one side and the other side, respectively; a slit for supplying the microwaves supplied into the pair of waveguides into the ECR chamber; a reflector formed on the ECR chamber and having a curvature; a magnet portion disposed on the upper end of the reflector; and bias supply means for supplying a bias to the reflector.

Description

Neutral particle generator with ECR plasma generator

The present invention relates to a neutral particle generator including an ECR plasma generator, and more particularly, to a neutral particle generator including an ECR plasma generator for generating ECR plasma using microwaves for deposition and annealing on the surface of a substrate, etc. It relates to a particle generator.

Plasma refers to a group of charged cations and electrons generated by electric discharge, and a technology using plasma is currently used in the processing of various products. In particular, it is very usefully used as a technique for depositing a predetermined material on the surface of a semiconductor wafer or LCD substrate (Plasma-enhanced chemical vapor deposition, PECVD) and etching (Plasma Etch).

The plasma apparatus includes a capacitively coupled plasma, an inductively coupled plasma, and an electron cyclotron resonance (ECR) depending on a method of generating plasma. Among them, electron cyclotron resonance refers to a phenomenon of high-density plasma generation using a phenomenon in which resonance occurs when a microwave is applied and a magnetic field is applied to generate a cyclonic frequency of electrons in plasma equal to the frequency of microwave. is becoming

In general, the ECR deposition apparatus requires the configuration of the electromagnetic wave input condition, the magnetic field formation condition, and the ECR generation region, and includes a chamber for a work space, a microwave input means on one side of the chamber, a magnetic coil or permanent magnet installed in the chamber, etc. A self-generating means and a gas supplying means for supplying gas to the ECR plasma generating region may be provided.

To explain the working principle for this, when a microwave is input into the chamber while a magnetic field is formed inside the chamber by the magnetic generating means, an ECR phenomenon is generated, and the gas supplied to the generating region is ionized to generate plasma. Usually, a microwave having a frequency of 2.45 GHz is used, and the magnetic flux density for resonating with it is 875 Gauss.

On the other hand, plasma can be converted into neutral particles to treat the surface of the object to be deposited, and there are largely two methods for generating neutral particles from plasma. One of them is the generation of neutral particles by charge exchange caused by the collision of plasma and gas particles, and the other is the generation of neutral particles by the collision between plasma ions and a metal plate.

However, in the related art, the plasma distribution in the plasma chamber is not uniform, so the efficiency of converting plasma ions into neutral particles and the density of the generated neutral particles are low, and it is difficult to control the directionality of the neutral particles and the number of collisions.

Korean Patent Registration No. 10-0555849 (Title of Invention: Neutral Particle Beam Processing Device)

The problem to be solved by the present invention is to increase the neutral particle conversion efficiency of plasma ions, to uniform the density distribution of neutral particles, and to propose a neutral particle generator including an ECR plasma generator that increases the flux of neutral particles. .

The problem to be solved by the present invention is to improve the uniformity of the plasma in the longitudinal direction of the linear reactor (chamber) and increase the flux of neutral particles by improving the plasma density adjacent to the reflector. To propose a neutral particle generator including an ECR plasma generator that improves annealing quality.

A neutral particle generator including an ECR plasma generator according to an embodiment of the present invention includes: a pair of waveguides formed in a tubular shape on one side and the other side, respectively; a slit for supplying the microwaves supplied into the pair of waveguides into the ECR chamber; a reflector formed on the ECR chamber and having a curvature; a magnet portion disposed on the upper end of the reflector; and bias supply means for supplying a bias to the reflector.

The neutral particle generating device including the ECR plasma generating device according to the present invention has a high density of neutral particles generated from the reflector due to the shape of the reflector having an ECR plasma effect and curvature due to the permanent magnet located on the upper end of the reflector. ) and the sample passing through the area in a scan method can obtain the maximized annealing effect due to the concentrated neutral particles.

Unlike CVD or sputtering, annealing by neutral particles has a certain threshold effect and is only effective above a certain neutral particle flux.

1 is a perspective view showing a neutral particle generator including an ECR plasma generator proposed by the present invention.
2 is a plan sectional view showing one form of a neutral particle generating device including an ECR plasma generating device proposed by the present invention.
Figure 3 is a side cross-sectional view showing one form of the neutral particle generator including the ECR plasma generator proposed by the present invention.
4 is a plan cross-sectional view showing another type of slit arrangement of the neutral particle generating device including the ECR plasma generating device proposed in the present invention.
5 is a first embodiment illustrating an arrangement structure of a slit in a waveguide according to an embodiment of the present invention.
6 is a second embodiment illustrating an arrangement structure of a slit in a waveguide according to an embodiment of the present invention.

The foregoing and further aspects of the present invention will become more apparent through preferred embodiments described with reference to the accompanying drawings. Hereinafter, it will be described in detail so that those skilled in the art can easily understand and reproduce through these embodiments of the present invention.

The neutral particle generator including the ECR plasma generator proposed in the present invention does not form a separate limiter. In general, the limiter prevents the passage of plasma ions and electrons and serves to selectively pass neutral particles, but in the deposition process, the limiter has a problem of significantly lowering the deposition rate. Accordingly, the neutral particle generator proposed in the present invention proposes a neutral particle generator including an ECR plasma generator in which a limiter applied to a thin film deposition process is not formed.

Figure 1 shows a perspective view of a neutral particle generator including an ECR plasma generator according to an embodiment of the present invention, Figure 2 is a neutral particle generator including an ECR plasma generator according to an embodiment of the present invention It shows a plan cross-sectional view of the apparatus, Figure 3 shows a side cross-sectional view of the neutral particle generator including the ECR plasma generator according to an embodiment of the present invention.

1 to 3 , the neutral particle generating device 100 including the ECR plasma generating device includes a waveguide 110 , a magnet unit 120 , an ECR chamber 130 , a slit 140 , and a reflector 150 . may include Of course, other configurations other than the above-described configuration may be included in the neutral particle generator 100 including the ECR plasma generator proposed in the present invention.

The waveguides 110 are a pair, have a straight tube shape in the longitudinal direction of the x-axis direction, and may be disposed to face each other while being spaced apart from each other by a predetermined distance. Microwave supply means (not shown) each including a microwave generator is connected to the end of the waveguide, and the microwaves supplied from the microwave supply means may flow into the inside of the waveguide 110 .

Microwaves may be supplied to the pair of waveguides 110 from mutually opposite directions, respectively. That is, the microwave may be supplied to the waveguide 110 on one side in the x-axis direction, and the microwave may be supplied to the waveguide 110 on the other side in the -x-axis direction. Microwaves become weaker as they move away from the microwave supply means, and since the pair of waveguides 110 may receive microwaves from opposite directions, the microwave supply deviation is offset and a relatively uniform plasma can be generated. In addition, since the microwave only passes through a straight section, distortion and loss of microwave energy can be minimized.

The microwaves introduced into the pair of waveguides 110 may be supplied into the ECR chamber 130 through the slit 140 . The microwave introduced into the waveguide 110 proposed in the present invention may be a stationary wave.

The ECR chamber 130 is positioned between the pair of waveguides 110 and may have a linear shape along the x-axis direction, which is the longitudinal direction. The ECR chamber 130 may be a space in which an electron cyclotron resonance (ECR) plasma is generated. An electron cyclotron resonance phenomenon is generated inside the ECR chamber 130, and when a plasma generating gas is injected in the electron cyclotron resonance state, ECR plasma may be generated. The injected plasma generating gas may be, for example, argon (Ar) gas, nitrogen (N ₂ ) gas, or the like, but is not limited thereto.

The magnet part is formed at the top of the ECR chamber. As a magnetic field field (M.F) generating means, the magnet unit may include a first polarity magnet 120a having a first polarity and a second polarity magnet 120b having a polarity different from the first polarity. For example, when the first polarity magnet 120a has an N pole, the second polarity magnet 120b may have an S pole. On the other hand, the distance between the magnets may be adjusted so that the magnetic field (M.F) 875Gauss of the first polarity magnet 120a and the second polarity magnet 120b approaches each other. In this case, plasma having a relatively uniform density may be formed in all regions within the ECR chamber 130 .

In the magnet part, a first polarity magnet having a first polarity formed long in the longitudinal direction of the ECR chamber 130 is disposed in the center of the upper end of the ECR chamber, and the ECR chamber 1300 is spaced apart from the first polarity by a certain distance on both sides. A second polarity magnet having a second polarity formed elongated in the longitudinal direction of is arranged, in addition, the second polarity magnet may be formed in an elliptical shape by being spaced apart a certain distance in a state in which the first polarity magnet is disposed therein. The second polarity magnet may be formed in an elliptical shape, and the first polarity magnet may be formed in a straight line shape inside the second polarity magnet.

Although the present invention shows a magnet as a means for generating a magnetic field, the present invention is not limited thereto, and a magnetic coil that is a device capable of generating a magnetic field may also be included.

The slit 140 communicates with the waveguide 110 in the x-axis direction, which is the longitudinal direction, and may be positioned to face the ECR chamber 130 .

The microwave supplied to the waveguide 110 is supplied to the inside of the ECR chamber 130 through the slit 140 , and the plasma frequency and the micro frequency at a point of 875 Gauss of the magnetic field MF formed by the magnet unit 120 . , and electron cyclotron resonance occurs. At this time, when gas is injected into the ECR chamber 130 , the gas is ionized to form a plasma, electrons in the plasma are accelerated by a resonance phenomenon, and a high-density ECR plasma can be generated inside the chamber 130 . .

The reflector 150 is positioned above the ECR chamber 130 and may convert plasma ions into neutral particles n. The reflector 150 may be made of tantalum (Ta), molybdenum (Mo), tungsten (W), platinum (Pt), gold (Au), stainless steel, or an alloy thereof. The bias supply unit 160 may be connected to the reflector 150 to supply a bias to the reflector 150 .

In relation to the present invention, the reflector 150 has a curvature so that the neutral particles reflected by the metal plate are concentrated and supplied in a specific direction. In this way, the neutral particle generator can supply high energy in a specific direction.

The surface of the reflector 150 should be mirror-treated to prevent scattering of neutral particles converted from ions. When scattering occurs, the flux of neutral particles reaching the top of the sample is significantly reduced. The bias voltage of the bias supply unit 160 may be appropriately adjusted in consideration of the required energy level of the neutral particle beam.

The neutral particle generator 100 including the ECR plasma generator converts ECR plasma ions generated in the ECR chamber 130 into neutral particles to deposit the surface of the substrate and perform annealing treatment on the surface of the substrate in a semiconductor process. It can be widely used for treatment.

According to FIG. 3 , when ECR plasma ions are generated in the ECR chamber 130 , the bias supply unit 180 applies a negative bias voltage to the reflector 150 , respectively, and the positively charged plasma ions are attracted to the reflector by attraction. (150).

In the conventional surface treatment of a substrate using neutral particles in a semiconductor process, the neutral particle conversion efficiency of plasma ions is low, and thus the surface treatment quality of the substrate is low.

On the other hand, the neutral particle generating device 100 including the ECR plasma generating device proposed in the present invention can focus the ECR plasma ions in a specific direction by using the reflector 150 having a curvature. Accordingly, it is possible to increase the quality of deposition and annealing of the substrate 200, which is a deposition target.

The substrate 200 may be seated on the upper portion of the transfer unit 300 and disposed under the ECR chamber 130 . The surface of the substrate 200 may be deposited and annealed while performing a reciprocating or continuous reciprocating motion in the lower portion of the ECR chamber 130 according to the driving of the transfer unit 300 . A plurality of substrates may be seated on the transfer unit 300 to process the plurality of substrates at once.

Figure 4 is similar to the neutral particle generator 100 including the ECR plasma generator of Figure 2 except for the slit 140, so the same reference numerals are used for the same parts, and detailed description thereof is omitted.

Referring to FIG. 4 , the neutral particle generator including the ECR plasma generator may include a slit 123 coupled to the waveguide 110 .

As shown in FIG. 4 , the slit formed on one side of the waveguide and the slit formed on the other side of the waveguide may not face each other, but may be alternately formed. As described above, the slit formed on one side of the chamber crosses the slit formed on the other side with each other to suppress the resonance of the two electric fields that can be generated when the opposite slits have the same width and the same height. becomes uniform, and thereby the density of plasma generated inside the chamber becomes uniform.

5 is a first embodiment illustrating an arrangement structure of a slit in a waveguide according to an embodiment of the present invention. Hereinafter, the arrangement structure of the magnet according to an embodiment of the present invention will be described in detail with reference to FIG. 5 .

Referring to FIG. 5 , slits 140 are formed in the waveguide 130 at regular intervals. In addition, as shown in FIG. 5 , the slit 140 is formed in a vertical direction in the waveguide. In relation to the present invention, the width of the slit is preferably 5 mm or less.

6 is a second embodiment illustrating an arrangement structure of a slit in a waveguide according to an embodiment of the present invention.

Referring to FIG. 6 , slits 140 are formed in the waveguide 130 at regular intervals. Unlike the slit of FIG. 5 which is formed to be long in the vertical direction, the slit 140 shown in FIG. 6 is formed to be inclined. As described above, the slit 140 is preferably formed at the point where the intensity of the microwave is greatest. However, a point at which a slit is formed and a point at which the intensity of the microwave is greatest may be different from a point where the wavelength of the microwave is temporarily changed or due to other temporary factors. In order to solve this problem, the present invention proposes a method of forming the shape of the slit to be obliquely inclined. When the slit is formed obliquely, the microwave may be introduced into the chamber through the slit even if the point at which the intensity of the microwave is greatest is temporarily changed. Accordingly, the present invention proposes a slit structure formed obliquely in addition to the slit structure formed in the vertical direction.

In particular, when looking at the inside of the neutral particle generating device from the outside, the slit formed in the waveguide on one side is inclined in a clockwise direction, and the slit formed in the waveguide on the other side is inclined in the counterclockwise direction. That is, the direction of the slit formed in the waveguide on one side and the direction of the slit formed in the waveguide on the other side are alternated with each other.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible therefrom. .

100: Neutral particle generator including an ECR plasma generator.
110: waveguide
120: magnet part
130: ECR chamber
140: slit
150: reflector
160: bias supply means

Claims (5)

a pair of waveguides respectively formed in a tubular shape on one side and the other side;
a slit for supplying the microwaves supplied into the pair of waveguides into the ECR chamber;
a reflector formed on the ECR chamber and having a curvature;
a magnet portion disposed on the upper end of the reflector; and
bias supply means for supplying a bias to the reflector;
Neutral particle generator including an ECR plasma generator comprising a.
The method of claim 1,
Neutral particle generator including an ECR plasma generator, characterized in that the reflector converts plasma ions of an upper region of the ECR plasma formed inside the chamber into neutral particles.
According to claim 1, wherein the magnet unit,
a first magnet elongated in the longitudinal direction of the ECR chamber at the center of the reflector; and
A neutral particle generator including an ECR plasma generator, which is spaced apart from the second magnet by a predetermined distance and includes a second magnet elongated in the longitudinal direction of the ECR chamber.
According to claim 1,
The slit is a neutral particle generator including an ECR plasma generator, characterized in that it is formed in a vertical direction or is formed obliquely.
5. The method of claim 4,
Neutral particle generator including an ECR plasma generator, characterized in that the slit formed in one side of the waveguide is inclined in a clockwise direction, and the slit formed in the other side of the waveguide is inclined in the counterclockwise direction.

Images