KR100415944B1 - inductive coupled plasma generation source - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma generation source embedded in a chamber type process module for semiconductor manufacturing. The present invention relates to a radio frequency (RF) power supply for supplying high frequency power and an impedance of a current supplied through the RF power supply. A plasma generating source comprising a plurality of plasma generating circuits, each including an impedance matching device and an antenna to which an electric current matched through the impedance matching device is applied to generate an electromagnetic field, provides a plasma having a more uniform density distribution. Make it possible to create.

Description

Inductively coupled plasma generation source

The present invention relates to a semiconductor manufacturing apparatus, and more particularly, to a plasma generating source mounted in a chamber type process module which is a semiconductor manufacturing apparatus.

In the semiconductor industry, which is rapidly developing as a high value-added industry, the development speed is further accelerated as semiconductor manufacturing technology such as deposition and etching using plasma is developed and utilized. In recent years, as the miniaturization and large area of semiconductor devices are strongly demanded, the process using the plasma plays an important role.

A method of generating such a plasma generally includes a capacitive coupling method or an inductive coupling method, among which an inductive coupled plasma (ICP) generation method has a relatively low operating pressure and an apparatus structure. It has a small constraint and has the advantage of generating high density plasma, replacing the existing capacitively coupled plasma (CCP) generation method.

In brief, the inductively coupled plasma generation method generates an electric field that changes with time in a discharge gas through an RF (Radio frequency) power supply supplying a high frequency voltage, thereby exciting the gas to generate a plasma, Maintaining, in particular, has the advantage that it can be used for direct reaction by generating a plasma on top of the wafer mounted in the chamber type process module for semiconductor manufacturing,

The structure of a chamber type process module in which the inductively coupled plasma generating source is mounted is briefly shown in FIG. 1, which is equipped with a wafer 1, which is an object to be processed, and a chamber 20, which is a sealed reaction vessel for directly processing the same. And a storage device 40 for storing necessary materials such as a source and a reactant material supplied into the chamber 20, and in particular, the chamber 20 may be supplied with the necessary materials from the storage device 40 described above. The inlet pipe 22 which makes it possible to carry out, and the discharge pipe 24 which makes it possible to control a pressure by discharging the gas in the inside.

In addition, the inside of the chamber 20 is divided into a first region 28a and a second region 28b by an insulating plate 26 that is horizontally installed. The second region 28b includes a wafer 1 as a processing target. A chuck 30 for gripping) is installed to allow the wafer 1 to be seated on an upper surface thereof, and a part or all of the plasma generating source 50 capable of generating plasma is mounted in the first region 28a. When the gaseous source and the reactant are introduced into the chamber 20 through the above-described storage device 40, the plasma generating source 50 generates a changing electromagnetic field to generate plasma in the second region 28b. Through this process, the wafer 1 on the chuck 30 is processed and processed.

In this case, the aforementioned plasma generation source 50 properly matches the impedance of the current applied through the first RF power supply 56 and the first RF power supply 56 that supplies high frequency power. The first impedance matching device 54 and a load, i.e., an antenna 52, for generating an electromagnetic field through the matched current are included. In this case, the aforementioned antenna is not a meaning of agreement in charge of transmitting and receiving signals in wireless communication, but of a broad meaning including a function of releasing power into a space. As used herein, it will be used in a consistent sense in the following specification.

In addition, the impact of plasma ions generated through the plasma generation source 50 is also applied to the inside of the chuck 30 located in the second region 28b of the chamber 20 and on which the wafer 1 is seated. A bias electrode 72 for regulating energy is located, which may be electrically connected to a second RF 76 power supply and a second impedance matching device 74 to which a voltage is applied.

In this case, the plasma generation source described above will be described in more detail with reference to FIG. 2, which has a configuration in which the first RF power supply 56, the first impedance matching device 54, and the antenna 52 are electrically connected. As described above, in particular, the antenna 52, which generates an electromagnetic field as a load, has a form in which a coil or tube made of a conductive material is wound in a spiral form.

However, there are some problems when using such a spiral antenna as a load, one of which generates an electromagnetic field having a non-uniform density. That is, referring to FIG. 3, which shows a cross section of the spiral antenna 52, it has a narrower diameter toward the center portion, and electromagnetic fields generated in adjacent areas interfere with each other, resulting in an electromagnetic field having a non-uniform density distribution. (B) will appear.

The electromagnetic field having such non-uniform density distribution eventually generates non-uniform density distribution plasma inside the chamber. As the non-uniform density plasma is difficult to control precisely, the fine processing and processing of the wafer becomes impossible. It is frequently observed in the case of different machining states depending on the position.

This problem is particularly acute with large area wafers, i.e. with the advantage that it is possible to obtain more semiconductor cells through the same process. Due to the non-uniform density distribution of the plasma, further adverse effects will occur.

An object of the present invention is to provide a plasma generating source capable of generating a plasma having a more uniform density distribution as devised to solve the above problems.

1 schematically illustrates the structure of a typical chambered process module for semiconductor manufacturing.

2 is a diagram illustrating a configuration of a general plasma generation source.

3 is a diagram conceptually illustrating a distribution of electromagnetic fields generated through a general plasma generation source.

4 is a view showing a schematic structure of a chamber type process module mounted with a plasma generating source according to the present invention;

5A and 5B are views showing the configuration of the first and second plasma generation circuits constituting the plasma source according to an embodiment of the present invention, respectively.

6 is a diagram conceptually illustrating a distribution of electromagnetic fields generated through a plasma generation source according to the present invention.

<Description of the symbols for the main parts of the drawings>

1: wafer 100: chamber type process module

120: chamber 122: inlet pipe

124: outlet pipe 126: insulation plate

128a, 128b: first and second regions 130: chuck

140: storage device 150: first plasma generating circuit

160: second plasma generating circuit

The present invention provides a plasma generating source that is partially or entirely mounted in a chamber-type process module, a semiconductor manufacturing apparatus, to achieve the above object, a first RF power supply, a first impedance matching device, and a first antenna A first plasma generating circuit comprising a; Provided is a plasma generation source comprising a second plasma generation circuit comprising a second RF power supply electrically connected, a second impedance matching device, and a second antenna positioned above the first antenna.

In this case, the first antenna is made of a material selected from a coil or a tube, characterized in that the spiral wound to narrow in one direction, the second antenna is characterized in that the plurality of plate-like conductive materials are connected in parallel to each other.

In addition, the first and the second plasma generating device is characterized in that it is mounted in a chamber-type process module for processing a 300mm large wafer, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. .

The plasma generating source according to the present invention is characterized in that it is mounted in a general chamber type process module. The chamber type process module in which the plasma generation source is mounted is briefly shown in FIG.

The chamber-type process module 100 in which the plasma generation source is mounted according to the present invention includes a chamber 120 which is a sealed reaction container in which a wafer 1, which is a processing target, is placed therein, and thus its direct processing and processing are performed. The storage device 140 includes a storage device 140 for storing necessary materials such as a source and a reactant supplied into the chamber 120.

In this case, the chamber 120 has an inlet pipe 122 through which the necessary material is supplied from the storage device 140 described above, and a discharge pipe 124 for adjusting the pressure by discharging the gaseous material therein, and the inside of the chamber 120. The insulating plate 126 which divides the first into the first region 128a and the second region 128b is terminated and installed. The chuck 130 holding the wafer 1 is mounted in the second region 128b. The wafer 1 is seated on the upper surface thereof, and part or all of the plasma generating source for generating plasma is mounted in the first region 128a in the same manner as in the general case.

At this time, preferably in order to control the impact energy of the plasma ions generated in the second region 128b through the plasma generation source mounted in the first region 128a, the bias electrode inside the chuck 130 172 is provided, and the bias electrode 172 is electrically connected to the first RF power source 176 and the first impedance electrode 174.

The plasma generation source according to the present invention for generating a plasma to the second region 128b by mounting part or all of the first region 128a of the chamber-type process module 100 having the above-described configuration may include a first plasma generation circuit. 150 and the second plasma generating circuit 160, that is, a second RF power supply 156, a second impedance matching device 154, and a first antenna The second plasma generating circuit 160 including the first plasma generating circuit 150, the third RF power supply 166, the third impedance matching device 164, and the second antenna 162. ) Is that.

Each of the plasma generating circuits 150 and 160 complements each other to generate a more uniform electromagnetic field. The first and second plasma generating circuits 150 and 160 are respectively illustrated in FIGS. Shown in 5b.

That is, the first plasma generation circuit 150 shown in FIG. 5A has a second RF power supply 156 for supplying high frequency power and an impedance of a current supplied through the second RF power supply 156. The second impedance matching device 154, which is a matching device for matching, and a first antenna 152 for generating an electromagnetic field by applying a matched current through the matching device. At this time, the first antenna 152 is made of a spiral coil or tube wound in one direction so as to become narrower, the electromagnetic field generated through this is densely concentrated toward its inner center, similar to a general case, and adjacent to each other The non-uniform electromagnetic field generated by the mutual interference phenomenon may appear, but this may be solved by the second antenna 162 of the second plasma generating circuit 160 located above the first antenna 152.

That is, the second plasma generation circuit 160 according to the present invention, as shown in Figure 5b, the third RF power supply 166 for supplying a high frequency power, and the current supplied through the third RF power supply 166 The third impedance matching device 164, which is a matching device for matching the impedance of the, and a second antenna 162 to generate an electromagnetic field by applying a matched current through the second antenna 162, the second antenna 162 Located above the first antenna 152 of the first plasma generation source 150 described above, in particular, the shape has a configuration in which a plurality of conductive materials on a plate are connected in parallel.

Therefore, the plasma generating source according to the present invention including the first and second plasma generating circuits 150 and 160 is more uniform through the complementary action of the first and second plasma generating circuits 150 and 160. It is possible to implement an electromagnetic field, which is spaced at an appropriate distance on the upper portion of the first antenna 152 of the first plasma generating circuit 150, as shown in Figure 6 the second of the second plasma generating circuit 160 Antenna 162 is located.

Therefore, the electromagnetic field generated from the first antenna 152 and the electromagnetic field generated from the second antenna 162 affect each other. In this case, the first and second plasma generation circuits 150 and 160 are respectively the second and the third. Since the impedance matching circuits 154 and 164 are provided, they can be controlled appropriately to adjust the current applied to the respective antennas 152 and 162 or to properly adjust the positions of the first and second antennas 152 and 162. It is possible to implement the electromagnetic field (B) having a uniform density distribution.

The plasma generating source according to the present invention has been exemplified as two plasma generating circuits each having a spiral antenna and an antenna made of a conductive material on a plurality of parallel connected plates, but the shape of each antenna is freely deformed. It is also possible to implement a plasma generating apparatus including three or more plasma generating circuits.

Therefore, the present invention is not limited to the above description, but is only an example, and may be freely modified without departing from the scope of the present invention according to the desired purpose.

The present invention enables the implementation of an electromagnetic field having a more uniform density distribution by providing a plasma generation source including a plurality of plasma generation circuits, each of which plays a complementary role. In particular, the first and second plasma generation circuits are A plurality of plate-like conductive materials provided in a spiral shape as a first antenna included in the first plasma generating circuit, and a second antenna included in the second plasma generating circuit, positioned on top of the first antenna and connected in parallel with each other. By employing the improved effect can be obtained.

In addition, each plasma generation circuit is provided with an independent RF power supply and an impedance matching device for controlling the current supplied through the respective RF power supplies, respectively, to control them, thereby realizing a more uniform electromagnetic field.

In particular, the plasma generating source according to the present invention can be mounted in a chamber-type process module used for processing and processing a large wafer having a diameter of 300 mm or more to obtain a more advantageous effect, which is more effective than the plasma generated through the plasma generating source. Since it is possible to give a uniform density distribution, it is possible to implement a reliable semiconductor device.

Claims (4)

As a plasma generating source mounted in part or all in a chamber type process module, a semiconductor manufacturing apparatus, A first plasma generation circuit comprising a first RF power supply electrically connected to the first RF power supply, a first impedance matching device, and a first antenna; A second plasma generation circuit comprising a second RF power source electrically connected to the second RF power supply; a second impedance matching device; and a second antenna positioned above the first antenna. Plasma generating source comprising a The method according to claim 1, The first antenna is made of a material selected from a coil or a tube and spirally wound so as to narrow in one direction. The method according to claim 1, The second antenna is a plasma generation source in which conductive materials on a plurality of plates are connected in parallel to each other. The method according to claim 1, The first and second plasma generators are mounted in a chamber type process module for processing a 300mm large wafer.