JPS6348933Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention consists of an ion generation chamber for converting gas particles into ion particles by gas discharge, and an ion beam in which ion particles are extracted from the ion generation chamber into a vacuum container. This relates to an ion beam device that is equipped with an introduction terminal, an introduction line, a pipe, etc. inside a vacuum vessel for supplying electric power and cooling water to the ion generation chamber and ion extraction electrode from outside the vacuum vessel. .

Conventional configurations and their problems In recent years, demand for devices using thin films has been increasing year by year, mainly in the semiconductor field. On the other hand, the manufacturing method includes various steps such as thin film deposition and removal, and appropriate processing methods and processing equipment are used depending on the application. Ion beam etching is being considered as one method for removing this thin film.

Hereinafter, a conventional ion beam apparatus will be described with reference to the drawings.

FIG. 1 shows a conventional ion beam device. In FIG. 1, 1 is a vacuum container capable of maintaining a vacuum state. Reference numeral 2 denotes an inlet for introducing gas particles, cooling water, electric power, etc. from the outside of the vacuum container 1 into the inside of the vacuum container 1, and their introduction paths are floated in terms of potential. 3 is an ion beam. 4 is a sample to be etched by ion beam 3 irradiation. 4a is a base material, 4b is a metal thin film to be etched as desired, and 4c is a resist mask. 5 is a sample stage for mounting the sample 4, and is cooled by cooling water. Reference numeral 6 denotes an ion generation chamber for converting gas particles introduced from the outside of the vacuum container 1 into ion particles, and has a gas excitation electrode, an excitation coil, etc. inside. Reference numeral 7 denotes an ion extraction electrode provided between the ion generation chamber 6 and the sample 4 in order to irradiate the sample 4 placed in the vacuum container 1 with the ion particles as an ion beam 3 . 8
is a pipe made of stainless steel for supplying gas particles and cooling water to the ion generation chamber 6. 9
is a power supply line made of copper for supplying power such as voltage and current to the ion generation chamber 6 and the ion extraction electrode 7. Reference numeral 10 indicates that during irradiation with the ion beam 3, secondary electrons generated by collisions of accelerated ion particles on the inner wall of the vacuum container 1, the sample 4, and the surfaces of other components located in the vacuum container 1 have a potential. The grounded material and shape of the plate-shaped cover is made of stainless steel and is used to prevent sparks and abnormal discharge from occurring on the surface of the parts.

First, the degree of vacuum in the vacuum container 1 is evacuated to 2×10 ^-5 Torr or less using a vacuum pump, and then the inlet 2
and through pipe 8, argon (hereinafter abbreviated as Ar)
Gas is introduced into the ion generation chamber 6 at a constant flow rate of 6.0 to 7.0 SCCM, and the degree of vacuum in the vacuum container 1 is adjusted.
Maintain at around 1.8×10 ^-4 Torr. Cooling water is introduced into the sample stage 5 and the ion generation chamber 6 through the inlet 2 and the pipe 8. Next, the inlet 2 and the power supply line 9
A predetermined electric power is introduced into the ion generation chamber 6 and the ion extraction electrode 7 through the ion generation chamber 6 and the ion extraction electrode 7. That is, the above operation causes a gas discharge of Ar in the ion generation chamber 6, and the Ar particles are excited and converted into Ar ion particles. At the same time, Ar ion particles generated in the ion generation chamber 6 are accelerated through the ion extraction electrode 7 and irradiated as the ion beam 3 onto the sample 4 side. When the accelerated Ar ion particles collide with the sample 4, the momentum of the Ar ion particles is transferred to the atoms of the sample 4, and the atoms are repelled by the Ar ion particles. Therefore, the ion beam etching method using Ar ion particles utilizes the sputtering effect, and proceeds when the energy of the Ar ion particles is greater than the bond energy (about 25 eV) of the constituent atoms of the sample 4.
In this case, the resist mask 4c is also the metal thin film 4b.
However, compared to the metal thin film 4b, the resist mask 4 is etched by the ion beam 3 irradiation.
If the thickness of the metal thin film 4b is increased, the exposed portion of the metal thin film 4b can be removed faster than the resist mask 4c, and a circuit of the metal thin film 4b can be formed on the base material. Further, the processing speed (etching speed) R(θ) of the sample 4 by irradiation with the ion beam 3 is generally expressed by the following equation.

R(θ)=A×I×S(θ)cosθ/n Å/min Here, n is the atomic density of sample 4 (atoms/cm ³ ),
I is the ion beam 3 current density (mA/cm ² ), θ is the ion beam 3 incident angle on the sample 4, S(θ) is the sputtering rate, and A is a constant. That is,
The processing speed of the sample 4 is proportional to the current density of the ion beam 3 and the energy of Ar ion particles contributing to the sputtering rate. On the other hand, during irradiation with the ion beam 3, secondary electrons are generated from the surfaces of the inner wall of the vacuum chamber 1, the sample 4, and other components located within the vacuum chamber 1 due to the collision of accelerated Ar ion particles. do. When these secondary electrons fly to parts having potential, such as the power inlet 2, the power supply line 9, and the ion generation chamber 6, sparks and abnormal discharge occur in those parts.

Conventionally, in order to prevent the above-mentioned sparks and abnormal discharges and stabilize the ion beam 3, a grounded cover 10 is installed, and 2
Attempts have been made to prevent the next electron from reaching the surface. However, depending on the structure of the cover 10, the degree of vacuum near the part with potential decreases, and cold cathode discharge tends to occur inside the cover 10. Therefore, it was necessary to arrange it. In other words, Patsien's law was applied to make it difficult for cold cathode discharge to occur. Therefore, the structure of the ion beam device has become complicated. Also, cover 1
Since 0 used a stainless steel plate with good conductivity, it was extremely difficult to change the arrangement of the ion beam 3 generating section to an arbitrary position within the vacuum vessel 1 due to the configuration of the ion beam device. As described above, the conventional ion beam apparatus has the disadvantage that the cover 10 makes the apparatus complicated.

Purpose of the invention The present invention eliminates these conventional drawbacks. It has a simple structure and can suppress secondary electrons. Moreover, the ion beam generation section can be placed anywhere in the vacuum chamber. An object of the present invention is to provide an ion beam device that can be easily changed to a different position.

Composition of the invention This invention consists of a vacuum container that can maintain a vacuum state, an ion generation chamber installed inside the vacuum container to convert gas particles introduced from outside the vacuum container into ion particles, and a chamber that converts the ion particles into ion particles. As a beam
In order to irradiate the workpiece placed in the vacuum container, electric power is supplied from outside the vacuum container to the ion extraction electrode provided between the ion generation chamber and the workpiece, and to the ion generation chamber and the ion extraction electrode. and the vicinity of at least a portion having a positive potential of the power supply component, cooling water supply component, and gas supply component for supplying cooling water, the ion generation chamber, the ion extraction electrode, the power supply component, the cooling water supply component, and the gas supply component. By covering parts with electric potential, such as power supply parts, cooling water supply parts, and gas supply parts, with the covers according to potential, ions can be removed. During beam irradiation, the secondary electrons generated during beam irradiation are prevented from flying to the surfaces of these parts, and sparks and abnormal discharges are prevented from occurring in the parts with the above potential, and the vacuum level inside the cover is This prevents the occurrence of cold cathode discharge inside the cover due to changes, making it possible to generate an ion beam stably, and furthermore, making it possible to easily move the ion beam generator to any position within the vacuum vessel. It has the unique effect of becoming .

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows an ion beam apparatus according to a first embodiment of the present invention. In Figure 2,
11 is a vacuum container capable of maintaining a vacuum state; 12 is an ion generation chamber provided within the vacuum container 11 for converting gas particles introduced from outside the vacuum container 11 into ion particles; 13 is an ion generation chamber An ion extraction electrode made of molybdenum is provided between the ion generation chamber 12 and the workpiece in order to irradiate particles as an ion beam to a workpiece placed in the vacuum container 11; reference numeral 14 denotes an ion generation chamber. 12
and a power supply component for supplying power to the ion extraction electrode 13, etc.; 15 is the ion generation chamber 12;
and a cooling water supply component for supplying cooling water to the ion extraction electrode 13 etc.; 16 is the ion generation chamber 1;
2, a gas supply component 17 for supplying gas to the ion generation chamber 12, an ion extraction electrode 13, a power supply component 14, and a cooling water supply component 15;
and a cover located near at least a portion having a positive potential of the gas supply component and covering the portion having a potential in a floating state and independently for each potential; 18 is a workpiece; 19 is a sample stage, and 20 is an ion beam.

The operation of the ion beam apparatus configured as described above will be described below.

First, the inside of the vacuum container 11 is evacuated by a vacuum pump until the degree of vacuum inside the vacuum container 11 reaches 2×10 ^-5 Torr or less, and then the gas is supplied from the outside of the vacuum container 11 through the gas supply part 16. Ion generation chamber 12
To, argon (hereinafter abbreviated as Ar) gas from 6.0 to
It is introduced at a flow rate of 8.0 SCCM so that the degree of vacuum within the vacuum vessel 11 is approximately 1.8×10 ^-4 Torr.
Further, cooling water is introduced into the ion generation chamber 12 and the sample stage 19 holding the workpiece 18 through the cooling water supply component 15 . Next, power is introduced into the ion generation chamber 12 and the ion extraction electrode 13 from the outside of the vacuum chamber 11 through the power supply component 14 to generate plasma in the ion generation chamber 12 . Gas particles are converted into Ar ion particles by excitation. At the same time, Ar ion particles are irradiated as an ion beam 20 toward the workpiece 18 in an accelerated state by the potential of the ion extraction electrode 13. During generation of the ion beam 20, secondary electrons are generated from the inner wall of the vacuum chamber 11, the workpiece 18, and the surfaces of other components located inside the vacuum chamber 11.
It prevents the secondary electrons from flying to parts with potential such as the ion generation chamber 12, the ion extraction electrode 13, the power supply part 14, the cooling water supply part 15, the gas supply part 16, etc. It is possible to prevent the occurrence of sparks and abnormal discharges. Furthermore, even if the degree of vacuum of the part with potential changes, the cover 17 is in a potential floating state and covers the parts with potential independently for each potential. Cold cathode discharge does not occur. Furthermore, since the cover 11 floats in terms of potential, there is no need for the cover 17 to be placed close to a part that has a potential, which allows the structure of the ion beam device to be simplified, and the cover 17 can be By using a flexible tube made of Teflon for part of the cooling water supply part 15 and a flexible tube made of Teflon for part of the gas supply part 16, the ion beam 2 in the ion beam apparatus is
It becomes possible to arrange the zero generation part at any position within the vacuum container 11.

As described above, according to the present embodiment, by providing the cover 17 which is in a potential floating state and covers the potential-bearing parts independently for each potential, the potential-bearing parts of the ion beam device can be The ion beam 20 can be stably generated by preventing sparks, abnormal discharge, cold cathode discharge, etc. Further, if a flexible tube made of an insulating material is used as a part of the cover 17, the ion beam 20 generating section of the ion beam device can be easily placed at any position within the vacuum vessel 11.

Effects of the invention As described above, the present invention stabilizes the generation of ion beams by providing covers that independently cover parts of the ion beam device that are in a floating state and have a positive potential for each potential. In addition, the ion beam generating section can be easily installed at any position within the vacuum container, which has great practical effects.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of a conventional ion beam device, and FIG. 2 is a front sectional view of an ion beam device according to an embodiment of the present invention. 11... Vacuum container, 12... Ion generation chamber, 1
3... Ion extraction electrode, 14... Power supply component, 15... Cooling water supply component, 16... Gas supply component, 17... Cover.

Claims (1)

[Claims for Utility Model Registration] (1) A vacuum container capable of maintaining a vacuum state, and an ion generator provided within the vacuum container to convert gas particles introduced from outside the vacuum container into ion particles. an ion extraction electrode provided between the ion generation chamber and the workpiece so as to irradiate the ion particles as an ion beam onto the workpiece placed in the vacuum container; the ion generation chamber and the ion extraction chamber; A power supply component that supplies power to the electrode from outside the vacuum container, a cooling water supply component that supplies cooling water, a gas supply component that supplies gas to the ion generation chamber, the ion generation chamber and ion extraction electrode, and the power supply. An ion beam device comprising: a supply component; and a cover positioned near at least a portion having a positive potential of the cooling water supply component and the gas supply component and floating in potential. (2) The ion beam device according to claim 1, wherein the cover is provided to independently cover portions having potentials for each potential. (3) The ion beam device according to claim (1), wherein the ion particles are argon ion particles. (4) The ion beam apparatus according to claim 1, wherein a portion of the gas supply component and the cooling water supply component are flexible tubes made of Teflon. (5) The ion beam device according to claim (1), wherein the cover for a portion of the power supply component is a flexible tube made of Teflon.