KR101058832B1 - Antenna Structure of Substrate Processing Equipment Using Plasma - Google Patents

Abstract

An antenna structure of a substrate processing apparatus using plasma according to the present invention includes a center introducer to which power is applied; A plurality of antenna bodies branched from the center introduction body in a parallel structure to have a symmetrical structure, each antenna body having a first straight portion extending linearly in the radial direction from the center introduction body, and an end of the first straight portion; A first straight portion connected vertically in the downward direction in the second direction, a second straight portion extending shorter than the length of the first straight portion toward the center introduction body at an angle with the first straight portion at the end of the first vertical portion, and the second straight portion By including a second vertical portion connected vertically from the end of the lower portion in the downward direction, and an arc portion extending in an arc shape from the end of the second vertical portion to the circumference formed by the whole antenna body, it is possible to supply power more stably, the plasma The density is uniformly formed and the plasma density can be increased to improve the substrate processing efficiency. .

Antenna, semiconductor, wafer, cooling,

Description

Antenna structure for substrate treatment device using plasma

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus using a plasma used in a manufacturing process such as a semiconductor, and more particularly to an antenna provided in a substrate processing apparatus using a plasma.

BACKGROUND OF THE INVENTION In a manufacturing process of a semiconductor or flat panel display device, a method using a plasma is widely used in a unit process such as dry etching, physical or chemical vapor deposition, photoresist cleaning, and other surface treatment in a manufacturing process of a wafer or a substrate.

Substrate processing apparatus using plasma is classified into capacitively coupled plasma (CCP) and inductively coupled plasma (ICP) according to a method of generating plasma.

The CCP method is a method of generating a plasma by using an RF electric field formed vertically between both electrodes by applying RF power to the parallel plate electrodes facing each other, and the ICP method is a raw material using an induction electric field induced by an RF antenna. This is how the material is transformed into plasma.

FIG. 1 schematically illustrates a configuration of an ICP type substrate processing apparatus. Referring to FIG. 1, a substrate support in which a substrate 11 is disposed and a substrate S positioned on an upper surface of the chamber 11 is formed. 12), the gas injection means 13 which supplies a raw material to the upper part of the board | substrate support 12 is comprised.

The upper part of the chamber 11 is sealed by the dielectric plate 14, and the RF antenna 15 is installed on the upper part of the dielectric plate 14. The RF antenna 15 is connected to the RF power source 17, and a matching circuit 16 for impedance matching is installed between the RF antenna 15 and the RF power source 17.

The gas injection means 13 may be configured as an injector symmetrically installed along the chamber sidewall as shown, but may be configured in a showerhead manner below the dielectric plate 14.

In a typical PECVD apparatus, the substrate support 12 is often grounded as shown, but in a high density plasma CVD (HDPCVD) apparatus which performs a gap fill process of a contact hole or a trench, deposition and etching are performed in parallel, so that the substrate is controlled for ion control. A bias RF power source may also be connected to the support 12.

The dielectric plate 14 serves to help transfer energy from the RF power source 17 to the plasma by inductive coupling by reducing capacitive coupling between the RF antenna 15 and the plasma.

The time-varying magnetic field in the vertical direction is generated by the RF power supplied from the RF power source 17 around the RF antenna 15, and the electric field in the horizontal direction is induced by the time-varying magnetic field inside the chamber 11. .

As the electrons accelerated by the induced electric field collide with the neutral gas, ions and radicals are generated to perform deposition or etching processes on the substrate.

The RF antenna 15 directly affects the plasma density inside the chamber 11 according to its shape or installation position.

For example, as shown in FIG. 2A, a spiral RF antenna 20 spirally wound around one coil generates a large voltage drop between a power supply terminal and a ground terminal, and thus, the RF power source 17. The plasma density is high in the connected center and the plasma density tends to decrease toward the periphery.

In addition, the power efficiency is very low due to the voltage drop, and in particular, as the size of the chamber increases, this problem becomes more serious.

FIG. 2B is a parallel RF antenna 30 introduced to improve the problem of the spiral RF antenna 10, and includes circular first, second and third loop antennas 31, 32, and 33 having different diameters. Arranged in a concentric manner, the loop antennas 31, 32, 33 are connected in parallel to the RF power source 17.

Since the parallel RF antenna 30 uses a loop antenna having a relatively short length compared to the spiral RF antenna 20, the power efficiency is higher than that of the spiral RF antenna 20. However, as the length of the loop antenna increases toward the outside, the voltage drop occurs relatively at the peripheral part, and thus, the plasma density tends to be lower at the peripheral part than the central part.

As such, since the plasma density is directly influenced by the shape and the installation position of the RF antenna 30, various methods for improving the plasma density have been attempted.

Referring to this method, first, as shown in FIG. 3A, the thickness of the dielectric plate 14 positioned under the RF antenna 15 is differently produced according to the position.

For example, if the plasma density is formed higher in the chamber center than in the periphery, the dielectric plate 14 having a relatively thick central part or a relatively thin peripheral part may be used to lower the plasma density at the chamber center or the plasma density at the periphery. Increase

Second, as shown in FIG. 3B, the loop antennas or coils are arranged relatively densely in the region where the plasma density is low, without spacing the intervals of the loop antennas or coils constituting the RF antenna 15 at equal intervals. In the region of high plasma density, the method is arranged relatively broadly.

Therefore, the plasma density is relatively low in the region in which the loop antenna or the coil is widely disposed, thereby controlling the plasma density. In the drawings, the distance between the loop antennas or the coils is closer to the periphery.

Third, as illustrated in FIG. 3C, the dielectric plate 14 is manufactured in a dome shape to maximize the center of the RF antenna 15 that generates a relatively strong RF electric field from the substrate support 12.

Therefore, the plasma density at the center is lowered, thereby obtaining a plasma having an overall uniform density distribution.

There are other ways to control the processor parameters, but this is a relatively complex and difficult process.

As described above, conventional antennas used in a substrate (wafer) processing apparatus, such as semiconductor equipment, are complicated in overall structure because they adjust the distance between antennas or change the thickness or structure of the dielectric plate to uniformly generate plasma inside the chamber. However, there is a problem in that plasma is generated uniformly while reducing power consumption.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the antenna can be provided in a parallel and multi-layered structure to supply power more stably. An object of the present invention is to provide an antenna structure of a substrate processing apparatus using plasma, which can increase the substrate processing efficiency.

In addition, the present invention is to provide an antenna structure of a substrate processing apparatus using a plasma to increase the substrate processing efficiency by applying a higher power to the antenna by configuring the antenna in the tube type to pass through the cooling fluid therein There is a purpose.

An antenna structure of a substrate processing apparatus using a plasma according to the present invention for realizing the above object includes a center introducer to which power is applied; And a plurality of antenna bodies branched from the center introducer to have a symmetrical structure in a parallel structure, wherein each antenna body comprises: a first straight portion extending linearly in a radial direction from the center introducer; A first vertical portion vertically connected downward from the end of the portion, a second straight portion extending shorter than the length of the first straight portion toward the center introduction body at an angle with the first straight portion at the end of the first vertical portion, It characterized in that it comprises a second vertical portion connected vertically from the end of the second straight portion in the downward direction, and an arc portion extending in an arc shape from the end of the second vertical portion to the circumference formed by the entire antenna body.

It is preferable that the said center introducer is comprised by the power supply introduction part set up in the direction perpendicular | vertical to the center of a distribution part.

Preferably, the second straight portion is twisted in a range of an acute angle with the first straight portion in a direction in which the arc portion continues.

The arc portion is preferably formed to have a size that the outer portion inscribed in the circumference of the entire antenna body.

Preferably, the end portion of the arc portion includes a third vertical portion vertically connected upwardly.

Preferably, the antenna body is configured such that three antenna bodies are arranged at intervals of 120 degrees around the center introduction body.

In this case, the antenna body has a first antenna body, a second antenna body, and a third antenna body connected to the center introducer in order, and the arc portion of the first antenna body is formed of the third antenna body. It may be configured to extend between the first vertical portion and the arc portion of the second antenna body.

On the other hand, each antenna body may be formed in a tubular structure so that the cooling fluid passes.

In this case, it is preferable that a cooling passage is formed in the center introduction body so that the cooling fluid passes through each of the antenna bodies, and a nipple connected to each cooling passage is formed outside.

And the cooling fluid may be configured to be introduced into the cooling passage of the center introduction body and discharged to the end of the arc portion.

Since the antenna structure of the substrate processing apparatus using the plasma according to the present invention is parallel and is arranged in three-dimensionally uniform intervals, it is possible to supply power to the antenna more stably and to reduce arcing defects. Even with the power consumption, the plasma density is uniformly formed, and the plasma density is increased to improve the substrate processing efficiency.

In addition, the present invention is configured by the antenna tube type to allow the cooling fluid to pass through the higher power can be applied to the antenna has a strong and uniform plasma formation has the effect of increasing the substrate processing efficiency do.

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

4 is a schematic diagram illustrating a substrate processing apparatus having an antenna according to the present invention.

As illustrated in FIG. 4, a semiconductor manufacturing apparatus equipped with an antenna according to the present invention, that is, a substrate (wafer) processing apparatus, includes a substrate support 52 on which a substrate is supported under a chamber 50. The gas supply unit 54 supplying a process gas to the upper portion of the chamber 50 and an antenna 60 for generating plasma are provided.

Here, the chamber 50 may be configured to be separated from an area where the dielectric plate 56 is provided at an upper portion thereof, and the gas supply unit 54 is introduced into the space below the dielectric plate 56. It is configured. The gas supply unit 54 may be configured in a showerhead manner in the chamber 50.

In Fig. 4, reference numerals 81 and 83 are cooling fluid inlet tubes and cooling fluid outlet tubes through which cooling fluid is supplied and discharged, and these tubes are preferably connected to a cooling unit for circulating the cooling fluid.

Reference numeral 57 denotes a matching circuit for impedance matching between the antenna 60 and the RF power source 58. The RF power source 58 and the matching circuit 57 constitute a power supply unit.

Here, the antenna has a parallel structure, which will be described in detail with reference to FIGS. 5 to 8.

5 to 8 are views showing the antenna according to the present invention, Figure 5 is a perspective view of the assembled state, Figure 6 is an exploded perspective view, Figure 7 is a plan view, Figure 8 is a front view, Figure 9 is a view of the current and cooling fluid A reference diagram showing the flow.

The antenna 60 according to the present invention is largely branched so as to have a symmetrical structure with a center introducer 61 to which power is supplied from the power supply units 57 and 58 and a parallel structure from the center introducer 61. It consists of a plurality of antenna body 70. In the embodiment of the present invention described below, the antenna body 70 will be described centering on a structure in which three antenna bodies 70 are arranged at intervals of 120 degrees.

The center introducer 61 includes a power supply introducer 62 which is erected in a direction perpendicular to the center of the distribution unit 63 where the plurality of antenna bodies 70 branch. This power supply introduction section 62 is configured to be electrically connected to the positive voltage circuit 57 side for supplying power in order to receive power from the power supply section.

In addition, the center introducer 61 is configured to supply cooling fluid to each of the three antenna bodies 70, which will be described later.

The antenna body 70, as illustrated in the figure, is configured to be uniformly arranged at intervals of 120 degrees around the center introducer 61, the configuration of each antenna body (70; 70A, 70B, 70C) Explain.

Each antenna body 70 has a first straight portion 71, a first vertical portion 72, a second straight portion 73, a second vertical portion 74, and an arc from the center introducer 61. The portion 75 and the third vertical portion 76 are configured to be sequentially connected.

Each of the antenna bodies 70 is arranged such that the first straight portion 71, the second straight portion 73, and the circular arc portion 75 are located in different horizontal spaces in the horizontal direction, and the first vertical portion 72. ) And the second vertical portion 74 are arranged in the vertical direction.

Each component part of each antenna body 70 is demonstrated.

The first straight portion 71 extends straight in the radial direction from the center introduction body 61. In the drawing, three first straight portions 71 are connected in a radial structure at intervals of 120 degrees, and portions connected to the first vertical portions 72 are approximately different antenna bodies 70 as shown in FIG. 7. It is preferable to be configured to continue to the position where the circular arc (75) meets.

The first vertical portion 72 is vertically connected at the end of the first straight portion 71 in the downward direction. In this case, the length of the first vertical portion 72 may be appropriately set in consideration of the internal space of the entire chamber 50.

Both ends of the first vertical portion 72 are connected to each other by a coupler 77 having a hexahedral structure to be connected to the first straight portion 71 and the second straight portion 73.

The second straight portion 73 extends toward the center introduction body 61 at an end of the first vertical portion 72 at a predetermined angle with the first straight portion 71, and thus, of the first straight portion 71. It is formed shorter than the length.

In addition, it is preferable that the second straight portion 73 is connected to the first straight portion 71 in an acute angle in a direction in which the next arc portion 75 continues. This is to generate the plasma density as a whole uniformly in the chamber 50.

The second vertical portion 74 is vertically connected at the end of the second straight portion 73 in the downward direction. At this time, the second vertical portion 74 may be set to the same length as the length of the first vertical portion 72, the both ends of the second straight portion 73 and the arc portion 75 through the coupler 77 also. It is configured to be connected with).

The arc portion 75 extends in an arc shape from the end of the second vertical portion 74 to the circumference formed by the entire antenna body 70.

At this time, the circular arc portion 75 is preferably formed to have a size that the outer periphery of the circumference formed by the entire antenna body (70).

When the first antenna body 70A, the second antenna body 70B, and the third antenna body 70C are sequentially connected to the center introducing body 61, the first antenna body 70A is connected. The portion where the circular arc portion 75 ends is preferably configured to extend between the first vertical portion 72 of the third antenna body 70C and the circular arc portion 75 of the second antenna body 70B.

The third vertical portion 76 is also connected to the coupler 77 at the end of the circular arc portion 75 and vertically connected upwards.

The third vertical portion 76 may be configured to be electrically connected to the chamber 50 to serve as a ground terminal.

Reference numeral 78 denotes a ground terminal connected to the chamber provided in the third vertical portion 76.

On the other hand, each of the antenna body (70A) 70B (70C) may be formed in a tubular structure so that the cooling fluid passes.

Accordingly, a cooling passage 63a is formed in the center introduction body 61 so that cooling fluid passes through each of the antenna bodies 70, and nipples 65 connected to each cooling passage 63a are formed at the outside. do. The nipples 65 are respectively connected to the cooling fluid inlet tube 81 as shown in FIG. 4.

Each of the wire rod and coupler 77 constituting each antenna body 70 is configured to allow the cooling fluid to pass through, wherein the wire rod and the coupler 77 are disposed between the antenna portion and the portion through which the cooling fluid passes. Insulation tube for the insulation of can be configured.

Nipples 79 connected to the cooling channel are formed at the upper end of the third vertical portion 76. These nipples are respectively connected to the cooling fluid discharge pipe 83 as shown in FIG.

By such a structure, the cooling fluid is preferably configured to be introduced into the cooling passage of the center introduction body 61 and to be discharged to the outside through the third vertical portion 76 of the end portion of the arc portion 75.

In the above-described embodiments of the present invention, the semiconductor manufacturing equipment has been described, but the present invention is not limited thereto.

The technical idea described in the above-described embodiments of the present invention may be implemented independently, or may be implemented in combination with each other. While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. It is possible. Therefore, the technical protection scope of the present invention will be defined by the appended claims.

1 is a schematic configuration diagram of a general ICP type substrate processing apparatus.

2A and 2B illustrate various types of RF antennas, respectively.

3A to 3C illustrate various methods for improving the plasma density distribution, respectively.

4 is a schematic diagram illustrating a substrate processing apparatus using a plasma having an antenna according to the present invention.

5 is a perspective view showing an antenna according to the present invention.

6 is an exploded perspective view showing an antenna according to the present invention.

7 is a plan view showing an antenna according to the present invention.

8 is a front view showing an antenna according to the present invention.

9 is a reference perspective view showing the current flow and the cooling fluid flow of the antenna according to the present invention.

Claims (10)

A center introducer electrically connected to the power supply to receive power; Consists of a plurality of antenna body branched from the center introduction to have a symmetrical structure in a parallel structure, Each of the antenna bodies includes a first straight portion extending linearly from the center introduction body in a radial direction, a first vertical portion vertically connected downward from an end of the first linear portion, and a first straight portion at the end of the first vertical portion. A second straight portion extending shorter than the length of the first straight portion toward the center introduction body at a constant angle with the first straight portion, a second vertical portion vertically connected downward from the end of the second straight portion, and an end of the second vertical portion; The antenna structure of the substrate processing apparatus using the plasma, characterized in that it comprises an arc portion extending in an arc shape to the circumference of the entire antenna body. The method according to claim 1, The center introducer is an antenna structure of a substrate processing apparatus using a plasma, characterized in that the power introduction unit is arranged in a direction perpendicular to the center of the distribution unit. The method according to claim 1, The antenna structure of the substrate processing apparatus using the plasma, characterized in that the second straight portion is connected in a direction in which the arc portion continues in the range of the acute angle with the first straight portion. The method according to claim 1, The arc portion of the antenna structure of the substrate processing apparatus using a plasma, characterized in that the outer portion is formed in the size inscribed in the circumference of the entire antenna body. The method according to claim 1, The antenna structure of the substrate processing apparatus using the plasma, characterized in that at the end of the arc portion, a third vertical portion which is vertically connected upward. The method according to claim 1, The antenna body is an antenna structure of a substrate processing apparatus using a plasma, characterized in that three antenna bodies are arranged at intervals of 120 degrees around the center introduction body. The method according to claim 6, The antenna body has a first antenna body, a second antenna body, and a third antenna body connected to the center introducer in this order. And an arc portion of the first antenna body is configured to extend between the first vertical portion of the third antenna body and the arc portion of the second antenna body. The method according to any one of claims 1 to 7, The antenna structure of the substrate processing apparatus using a plasma, characterized in that each of the antenna body is made of a tubular structure so that the cooling fluid passes. The method according to claim 8, Cooling passages are formed in the center introduction body so that cooling fluid passes through the antenna bodies, and an nipple connected to each cooling passage is formed at an outer side of the center introduction body. The method according to claim 9, The cooling fluid is introduced into the cooling passage of the center introduction body and the antenna structure of the substrate processing apparatus using a plasma, characterized in that configured to be discharged to the end portion.

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