WO2013035983A1 - Apparatus and method for plasma ion implantation - Google Patents

Abstract

Provided are an apparatus and method for plasma ion implantation, capable of efficiently implanting ions of a raw material, which exists in a solid state when at room temperature, into the surface of a sample under a low processing pressure. The apparatus for plasma ion implantation according to one embodiment of the present invention comprises: a vacuum chamber maintaining a vacuum state therein; a magnetron sputtering source coupled to the vacuum chamber and generating a pulsed plasma inside the vacuum chamber; a conductive sample stage installed at a position inside the vacuum chamber opposing the magnetron sputtering source, and on which a sample is seated; and an RF-DC coupler which combines inputted pulsed DC power and RF power, and which supplies, to the magnetron sputtering source, combined RF-DC power, i.e. overlapped RF power and pulsed DC power.

Description

Plasma ion implantation device and method

The present invention relates to a plasma ion implantation apparatus and method for enabling plasma ion implantation of elements present in a solid state at room temperature.

Ion implantation is a technique in which ions are accelerated to tens to hundreds of keV and incident on the surface of a material. Ion implantation technology can form a modified layer up to several thousand micrometers below the surface of the material, and forms a gentle composition change layer, so that the coating layer peeling phenomenon due to heterogeneity of the material as in the coating is not fundamentally generated. Another advantage of ion implantation technology is that it is a high-energy process, so it is hardly restricted by thermodynamics, and because it is a room temperature process, there is no change in size or deterioration due to heat, and surface roughness is also not significantly affected. Can be. Furthermore, there is an advantage that it is easy to control the type, thickness and degree of modification of the modified layer by adjusting the type, energy, and amount of implanted ions.

However, despite many advantages of the ion implantation technology described above, the use of the ion implantation technology is very limited in other material fields except the semiconductor field. For this reason, the conventional ion implantation apparatus is a device developed for doping an impurity onto a semiconductor wafer, which is a planar sample, extracts ions from an ion source, accelerates them, and enters the sample in the form of an ion beam. You should shake the ion beam. This method of implanting ions in the form of ion beam has three-dimensional rotation and inclination of the sample for implanting ions into three-dimensional objects such as molds, tools, and mechanical component parts due to the principle of line-of-sight implantation. There are technical disadvantages such as the need for masking to prevent sputtering caused by incident ions. It is also a factor that makes the practical application of ion implantation technology difficult, with very expensive equipment costs compared to other surface modification equipment.

In order to overcome the disadvantages of the ion beam ion implantation technology, plasma ion implantation technology using plasma and high voltage pulses has been developed. Plasma ion implantation technology is a technology that can achieve surface modification by injecting ions uniformly on the surface of a large-area three-dimensional sample. That is, since plasma and high voltage pulses are used, uniform ion implantation rate to a large area sample is very fast, and an ion beam dispersing device or the like is not necessary. In addition, the use of plasma eliminates the inherent charge concentration on the sample surface, and the simple device provides excellent clustering with other thin film processing equipment and a very low cost. There is this.

However, most of the plasma ion implantation technologies that have been devised and used up to now are possible only in the gaseous state such as nitrogen, oxygen, irgon, methane, and in some cases (US Pat. No. 5,777,438, US Pat. No. 5,126,163). It is designed to enable plasma ion implantation of solid elements using pulse cathodic arcs. However, when the pulsed cathode arc plasma is used, it results in deposition on the surface of the ion implanted sample due to the generation of macro droplets caused by the arc, and a filter using a magnetic field must be used to prevent this. There are disadvantages.

In addition, as in the case of Korean Patent No. 10-1055396, there is a method of enabling the operation of the magnetron sputtering deposition source under low process pressure advantageous for plasma ion implantation by generating an inductively coupled plasma using a separately mounted RF antenna. However, when using such an RF antenna, it may cause the generation of polluted particles due to the peeling of the material deposited on the antenna surface, there is a disadvantage that the antenna must be replaced from time to time to prevent this.

Provided are a plasma ion implantation apparatus and method capable of efficiently ionizing ions of an element present in a solid state at room temperature to a surface of a sample at a low process pressure.

Plasma ion implantation apparatus according to an embodiment of the present invention is a vacuum chamber that maintains a vacuum state inside, the magnetron deposition source coupled to the vacuum chamber to generate a pulsed plasma inside the vacuum chamber, the position opposite the magnetron deposition source in the vacuum chamber A conductive sample mount installed on the sample to mount the sample, and an RF-DC coupling unit for supplying the RF-DC combined power of the RF power and the pulsed DC power to the magnetron deposition source by combining the input pulse DC power and RF power do. RF-DC combined power superimposed RF power and pulsed DC power can have a density value of 10W / cm ² ~ 10kW / cm ² , and the power density of RF power is 0.1W / cm ² ~ 2W / cm ² . Can be.

And a high voltage pulse power supply for accelerating the pulsed plasma generated from the magnetron deposition source to the sample side and supplying a high voltage pulse synchronized with the pulsed DC power input to the RF-DC coupling part to the sample mount, and is generated from the high voltage pulse power supply. The operating frequency of the high voltage pulse is 1Hz to 10kHz, which is the same frequency as the RF-DC combined power superimposed with the RF power supplied to the magnetron deposition source and the pulsed DC power, and the pulse width is 1usec to 200usec, and the negative pulse high voltage Can be -1kv to -100kV.

A gas supply unit for supplying a gas to be converted into a plasma inside the vacuum chamber, disposed in the gas supply path between the gas supply unit and the vacuum chamber and controls the pressure of the gas supplied from the gas supply unit into the vacuum chamber to maintain the set pressure inside the vacuum chamber A gas control unit, a first vacuum valve installed in the gas supply path between the gas control unit and the vacuum chamber, a vacuum pump holding the vacuum in the vacuum chamber, and a second vacuum valve installed in the gas discharge path between the vacuum pump and the vacuum chamber It may further include. The set pressure inside the vacuum chamber can be 0.1 mTorr to 2 mTorr.

An RF power supply unit for generating RF power and an RF matching unit coupled between the RF power supply unit and the RF-DC coupling unit for RF impedance matching, the pulse current meter for measuring plasma ion implantation current, plasma ion implantation voltage It may further include a monitoring unit for monitoring the plasma ion implantation current and the voltage connected to the pulse voltage meter, and the pulse current meter and the pulse voltage meter, respectively.

On the other hand, the plasma ion implantation method comprises the steps of placing the sample on the conductive sample mounting inside the vacuum chamber, maintaining the interior of the vacuum chamber in a vacuum state using a vacuum pump, supplying the gas to be plasmaized in the vacuum chamber and the internal pressure Maintaining the phase, supplying the RF-DC combined power of the RF power and the pulsed DC power superimposed on the magnetron deposition source to operate the magnetron deposition source, and applying a negative high voltage pulse to the conductive sample mount. Synchronizing and supplying at the same frequency as the pulsed DC power for operation, by accelerating the high-density solid element plasma ions generated from the magnetron deposition source toward the sample by using a negative high-voltage pulse supplied to the conductive sample holder Implanting ions into the surface of the sample.

The pressure inside the vacuum chamber can be 0.1mTorr ~ 2mTorr, RF-DC combined power superimposed RF power and pulsed DC power has a density value of 10W / cm ² ~ 10kW / cm ² , and frequency is 1Hz ~ 10kHz The pulse width can be 1usec to 200usec. The power density of the RF power superimposed on the pulsed DC power can be 0.1W / cm ^{2 to} 2W / cm ² , and the operating frequency of the high voltage pulse is the RF-power superimposed with the RF power supplied to the magnetron deposition source. It is 1 Hz-10 kHz which is the same frequency as DC coupling power, pulse width is 1usec-200usec, and negative pulse high voltage can be -1kv --100kV.

Plasma ion implantation apparatus and method provides a low frequency plasma ion implantation by supplying RF-DC coupled power with RF superimposition to the magnetron sputtering deposition source and supplying a negative high voltage pulse synchronized to the sample mount. There is an effect that can be performed at process pressure.

In addition, in order to operate the magnetron sputtering deposition source used as the deposition source for thin film deposition under a low process pressure, the RF power 4 supplies a superimposed RF-DC combined power and is synchronized with the negative high voltage. By supplying the pulse to the sample, there is an effect that the plasma ion implantation on the surface of the sample without energy loss due to the collision of the plasma ions generated from the magnetron sputtering deposition source with the gas particles.

In addition, plasma ions can be effectively implanted into the surface of a sample under low process pressure, and the ions of elements present in the solid state at room temperature can be widely applied to enhance the surface properties through ion implantation of various elements. .

1 is a block diagram showing a plasma ion implantation apparatus according to an embodiment of the present invention.

FIG. 2 is a graph illustrating a synchronization concept of the RF-DC coupled power superimposed with the RF power supplied to the magnetron deposition source and the time of the high voltage pulse supplied to the sample of the plasma ion implantation apparatus according to the embodiment of the present invention.

Figure 3a is a graph showing the discharge current according to the argon pressure of the magnetron deposition source operated using only a simple pulsed DC power according to an embodiment of the present invention.

Figure 3b is a graph showing the discharge current according to the argon pressure of the magnetron deposition source operated using the RF RF superimposed RF-DC combined power according to an embodiment of the present invention.

FIG. 4 is a graph illustrating OJ analysis results of measuring a distribution of aluminum elements in a depth direction of a silicon wafer sample in which aluminum plasma ions are implanted according to an exemplary embodiment of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” include plural forms as well, unless the context clearly indicates the opposite. As used herein, the term "comprising" embodies a particular characteristic, region, integer, step, operation, element, and / or component, and other specific characteristics, region, integer, step, operation, element, component, and / or group. It does not exclude the presence or addition of.

Unless defined otherwise, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Commonly defined terms used are additionally interpreted to have a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted in an ideal or very formal sense unless defined.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

1 is a block diagram of a plasma ion implantation apparatus using a pulse magnetron deposition source and a high voltage pulse by using a RF-DC combined power superimposed RF power and pulsed DC power according to an embodiment of the present invention. Referring to FIG. 1, the plasma ion implantation apparatus includes a vacuum chamber 1, a magnetron deposition source 9, a conductive sample mounting unit 12, an RF-DC coupling unit 7, and a high voltage pulse power supply unit 13. .

The vacuum chamber 1 has an inner space for plasma ion implantation, and the inner space maintains a vacuum state. The magnetron deposition source 9 is coupled to the upper side of the vacuum chamber 1 to generate ions of solid elements, and generates a pulsed plasma 10 by the magnetron deposition source 9. The conductive sample holder 12 is a portion on which the sample 11 is mounted, and is installed at a position opposite to the magnetron deposition source 9 in the vacuum chamber 1. The RF-DC coupling unit 7 combines the input pulse DC power 6 and the RF power 4 so that the RF power 4 and the pulse DC power 6 overlap the magnetron deposition source 9. Supply DC coupled power (8). The pulsed DC power 6 is generated in the pulsed DC power supply 5. The high voltage pulse power supply unit 13 accelerates the pulsed plasma 10 generated from the magnetron deposition source 9 to the sample 11 and the high voltage synchronized with the pulsed DC power 6 input to the RF-DC coupling unit 7. Pulse 14 is supplied to conductive sample mount 12. The high voltage pulse power supply unit 13 supplies the negative high voltage pulse 14 to the conductive sample holder 12.

Meanwhile, referring to FIG. 1, the plasma ion implantation apparatus includes a gas control unit 15, a gas supply unit 16, a vacuum pump 21, a first vacuum valve 22, a second vacuum valve 23, and an RF power supply unit ( 2), the RF matching section 3, the pulse current meter 17, the pulse voltage meter 18, and the monitoring unit 19 further includes.

The gas control unit 15 is disposed in the gas supply path between the gas supply unit 16 and the vacuum chamber 1 to regulate the gas flow rate. The gas regulating unit 15 functions to maintain the set pressure inside the vacuum chamber 1 by adjusting the pressure of the gas supplied from the gas supply unit 16 into the vacuum chamber 1. The gas supply unit 16 supplies a gas to be plasmaized into the vacuum chamber 1. The vacuum pump 21 functions to maintain the vacuum of the vacuum chamber (1). The first vacuum valve 22 is installed in the gas discharge path between the gas control unit 15 and the vacuum chamber 1 to control the flow of the gas amount according to the opening and closing degree. Reference numeral 20 means that the vacuum chamber 1 is electrically grounded. The second vacuum valve 23 is installed in the gas supply path between the vacuum pump 21 and the vacuum tank 1. On the other hand, the RF power supply unit 2 generates the RF power 4. The RF matching unit 3 is coupled between the RF power supply unit 2 and the RF-DC coupling unit to perform RF impedance matching. The pulse current meter 17 measures the plasma ion implantation current. The pulse voltage meter 18 measures the plasma ion implantation voltage. The monitoring unit 19 is connected to the pulse current meter 17 and the pulse voltage meter 18, respectively, to monitor plasma ion implantation current and voltage.

As described above, the plasma ion implantation apparatus supplies the RF-DC coupling power 8 with the RF superimposed on the magnetron deposition source 9, and the negative high voltage pulse (synchronized to the conductive sample mount 12) 14) enables plasma ion implantation of solid elements at low process pressures. Plasma ion implantation of a solid element is achieved by synchronizing the pulse magnetron deposition source 9 and the high voltage pulse 14 using the RF-DC combined power 8 overlapping the RF power 4 and the pulsed DC power 6. Make it efficient. That is, in order to operate the magnetron deposition source 9 used as the deposition source for thin film deposition under a low process pressure, the RF-DC combined power 8 in which the RF power 4 and the pulsed DC power 6 are superimposed is used. By supplying the negative high voltage pulse 14 synchronized with the sample 11 to the sample 11 so that plasma ions generated from the magnetron sputtering deposition source are not lost in energy due to collision with gas particles. Plasma ion implantation is allowed on the surface. In case of using the RF-DC combined power (8) in which the RF power (4) and the pulsed DC power (6) are superimposed for the operation of the magnetron deposition source (9), the operation using only a simple pulse DC power (6) Operation at lower process pressures is possible. Therefore, it is possible to prevent the loss of ion implantation energy due to collision with other gas particles during plasma ion implantation. In addition, there is no discharge delay phenomenon of the pulsed plasma, which may accelerate the ignition time.

In the plasma ion implantation apparatus according to the embodiment of the present invention, the pulse magnetron deposition source 9 and the high voltage pulse 14 using the RF-DC coupling power 8 in which the RF power 4 and the pulse DC power 6 are superimposed. Synchronize and use That is, after the sample 11 is mounted on the conductive sample mount 12 located in the vacuum chamber 1, the vacuum degree inside the vacuum chamber 1 is exhausted to the high vacuum region by using the vacuum pump 21. Thereafter, a gas for generating a plasma, but not necessarily limited thereto, is introduced into the vacuum chamber 1 through a gas supply unit 16 and a gas control unit 15 such as gas such as argon, nitrogen, oxygen, and methane. The pressure inside the vacuum chamber 1 is adjusted to a pressure of 0.1 mTorr to 2 mTorr. For this reason, even if the gas pressure inside the vacuum chamber 1 is lower than 0.1 mTorr, the plasma 10 may be used even when the RF power 4 and the pulsed DC power 6 overlapping the RF-DC combined power 8 are used. ), The energy loss of accelerated ions is very high at the high pressure of 2mTorr or higher due to the frequent collision of the accelerated ions and the surrounding gas particles at the plasma ion implantation. When using a process pressure of 2mTorr, considering that the average collision distance of the ions is only about 4cm, it can be obvious that the ion implantation is not performed smoothly at a pressure of 2mTorr or more.

As described above, when the pressure inside the vacuum chamber 1 is stabilized after the use of gas, the RF power 4 and the pulsed DC power 6 are superimposed on the magnetron deposition source 9 mounted on the vacuum chamber 1. The magnetron deposition source 9 is operated by supplying the RF-DC coupling power 8, and the negative high voltage pulse 14 is applied to the conductive sample mount 12 using the high voltage pulse power supply 13. Plasma ion implantation process is performed by supplying.

The negative power supplied to the RF-DC coupling power 8 and the conductive sample mount 12 in which the RF power 4 and the pulsed DC power 6 supplied to the magnetron deposition source 9 are superimposed. The high voltage pulses 14 are synchronized as shown in FIG. 2 to operate at the same frequency.

FIG. 2 is a graph illustrating a synchronization concept of the RF-DC coupled power superimposed with the RF power supplied to the magnetron deposition source and the time of the high voltage pulse supplied to the sample of the plasma ion implantation apparatus according to the embodiment of the present invention.

Referring to FIGS. 1 and 2, the moment when a high power density pulse DC power 6 is supplied to the magnetron deposition source 9 in which a low density plasma is maintained by the low power RF power 4. The solid element sputtered from the magnetron deposition source 9 is ionized by a high density plasma. The ions of the solid element generated as described above are accelerated to the sample 11 by the negative high voltage pulse 14 supplied to the conductive sample mount 12, and thus ion implantation is performed on the surface of the sample 11 to be synchronized. Should be done.

The power density of the RF power (4) to be supplied to the magnetron evaporation source (9) has a value of ^{0.1W / cm 2 ~2W / cm 2} . The frequency of the RF power 4 preferably has a frequency in the 1 to 30 MHz band which is most commonly used. The reason is that it is difficult to maintain the plasma by the RF power 4 when the RF power density uses a value of 0.1 W / cm ² or less. On the other hand, when the RF power density of 2W / cm ² or more is used because the sputtering of the target material by the RF power (4) occurs, a phenomenon that a thin film is deposited on the surface of the sample (11).

In addition, the pulse DC power density supplied to the magnetron deposition source 9 is set to have a value of 10 W / cm ² to 10 kW / cm ² . The reason for this is that it is difficult to generate a high-density plasma with high ionization rate from the magnetron deposition source 9 with a low pulse DC power 6 of 10 W / cm ² or less. On the other hand, in order to use a value of 10kW / cm ² or more, it is practically difficult to manufacture the pulsed DC power supply unit 5 or the RF-DC coupling unit 7 for combining the RF power 4 and the pulsed DC power supply 6. Because.

The operating frequency and pulse width of the pulsed DC power 6 used in the plasma ion implantation process are to have a frequency of 1 Hz to 10 kHz and a pulse width of 1usec to 200usec. This is because the plasma ion implantation process takes too much time at low frequencies below 1 Hz, thereby reducing the economic value of the present technology. In addition, it is because there is a lot of difficulty in manufacturing the pulsed DC power supply unit 5 that operates at a high frequency of 10kHz or more. When the pulse width is operated with a short pulse width of 1usec or less, the generation of high density plasma is not sufficient, so the ionization rate of the generated solid element is low. On the other hand, when a long pulse width of 200usec or more is used, the process is unstable because an arc is likely to occur in the magnetron deposition source 9 due to the high pulse power.

The operating frequency, pulse width, and negative (-) pulse high voltage of the high voltage pulse 14 supplied to the conductive sample mount 12 of the plasma ion implantation device are supplied to the magnetron deposition source 9 by the pulse DC power supply 6. It must be synchronized with the same frequency of 1Hz ~ 10kHz which is the same frequency as. Pulse widths of 1usec to 200 usec and negative pulse high voltages of -1kv to -100kV are used. For this reason, plasma ion implantation is not effective in the case of a pulse width of less than 1usec, and when plasma is operated by a long pulse of 200usec or more, a negative high voltage supplied to the conductive sample mount 12 causes plasma. There is a concern that the sheath expands too much and the plasma is turned off while touching the wall of the vacuum chamber 1. In addition, this is because an arc is more likely to occur as the time for which the high voltage is supplied to the conductive sample mounting table 12 becomes longer. In addition, the low voltage of -1kV or less has a disadvantage that the depth of ion implantation on the surface of the sample 11 is too low. This is because the manufacture of the high voltage pulse power supply unit 13 of -100 kV or more is practically difficult.

In the plasma ion implantation apparatus according to the embodiment of the present invention, the operation of the magnetron deposition source 9 used as the deposition source for thin film deposition is performed by the RF-DC combined power in which the RF power 4 and the pulsed DC power 6 overlap. Operate in pulse mode using (8). Then, by supplying the negative high voltage pulse 14 synchronized with the sample 11, the pulse plasma ions generated from the magnetron in the pulse mode can be effectively accelerated to be implanted into the surface of the sample 11. In case of using the RF-DC combined power (8) in which the RF power (4) and the pulsed DC power (6) are superimposed for the operation of the magnetron deposition source (9), the operation using only a simple pulse DC power (6) Operation at lower process pressures is possible. Therefore, it is possible to prevent the loss of ion implantation energy due to the collision with other gas particles during plasma ion implantation, and has the advantage of advancing the ignition time of the pulsed plasma. In addition, when the magnetron deposition source 9 is operated in a pulsed mode instead of continuous operation, the magnetron deposition source can be supplied at a very high moment when a pulse is supplied while maintaining a low average power so that there is no problem in cooling the magnetron target. High density plasma can be generated on the surface of (9). This increases the ionization rate of the element emitted from the surface of the magnetron deposition source 9. The ions of the sputtering target element generated in this way are accelerated toward the sample 11 by the synchronized negative high voltage pulse 14 applied to the sample 11 and ions are injected into the surface of the sample 11. do.

Experimental Example

According to an embodiment of the present invention, a solid element plasma using a magnetron deposition source 9 and a high voltage pulse 14 to which an RF-DC coupled power 8 in which an RF power 4 and a pulsed DC power 6 are superimposed is supplied. Ion implantation experiment was performed as follows. An aluminum target having a diameter of 75 mm and a thickness of 6.35 mm was used as the magnetron deposition source 9 for aluminum ion injection, and a silicon wafer was used as the ion injection sample 11. After attaching the sample 11 to the conductive sample holder 12, the vacuum chamber 1 was evacuated to a vacuum of 3 * 10 ^-6 Torr, and then argon gas was introduced to introduce the argon pressure inside the vacuum chamber 1. Was changed in the range of 0.6mTorr ~ 2mTorr. The magnetron deposition source 9 was operated by supplying pulsed DC power 6 to the aluminum magnetron deposition source 9, and the RF-DC coupling power 8 supplied to the magnetron deposition source 9 was -1.2 kV, The frequency of the RF-DC coupling power 8 was 100 Hz and the pulse width was 50 usec. In addition, in order to examine the effect of the superposition of the RF power (4), when only the pulse DC power (6) is supplied and the 13.56MHz, 10W RF power (4) (RF power density ~ 0.2W / cm ² ) The cases were compared and the discharge pulse current of the magnetron deposition source 9 was measured in order to investigate the pulse plasma generation during the operation of the aluminum magnetron deposition source 9.

Figure 3a is a graph showing the discharge current according to the argon pressure of the magnetron deposition source 9 operated using only a simple pulsed direct current (6) according to an embodiment of the present invention, Figure 3b is an embodiment of the present invention The graph shows the discharge current according to the argon pressure of the magnetron deposition source 9 operated using the RF-DC coupled power 8 in which the RF power 4 and the pulsed DC power 6 overlap.

Referring to FIG. 3A, when only the simple pulsed DC power 6 without RF power 4 is supplied, the minimum operating argon pressure of the aluminum magnetron deposition source 9 is 1.2 mTorr, and the magnetron at a pressure lower than that. It can be seen that the deposition source 9 cannot be operated. Referring to FIG. 3B, it can be seen that the minimum operating argon pressure of the aluminum magnetron deposition source 9 can be lowered to 0.7 mTorr when the pulsed DC power 6 is superimposed on the 10 W RF power 4. . 3A and 3B, when the discharge pulse current of the magnetron deposition source 9 is used, the discharge delay of about 20usec between the supply time of the pulse DC power 6 and the start of the discharge when the pulse DC power 6 is used alone. On the other hand, when the RF power 4 is superimposed, it can be seen that the discharge starts as soon as the pulsed DC power 6 is supplied without such a discharge delay phenomenon.

The magnetron deposition source 9 is operated by using only the pulsed DC power 6 by the above method, or by using the RF-DC coupled power 8 in which the RF power 4 and the pulsed DC power 6 are superimposed. While the negative high voltage pulse 14 was supplied to the sample 11, the aluminum plasma ion implantation process was performed for 15 minutes. When only the pulsed DC power (6) is used, the operating pressure is 1.5 mTorr. When the RF power (4) and the pulsed DC power (6) are superimposed, the operating pressure is 0.9 mTorr. It was. The high voltage pulse 14 value used in the ion implantation experiment was the same as -60 kV and 40usec, and the frequency was synchronized to 100 Hz which is the same as that of the magnetron deposition source 9. In addition, after supplying the pulsed DC power 6 for the magnetron deposition source 9 of 50usec, the high voltage pulse 14 of 40usec is supplied to the conductive sample mount 12 after about 10usec. Plasma ion implantation was performed at a high state. After the aluminum plasma ion implantation process, the OJ analysis was performed to determine the distribution of elemental depth in the silicon wafer.

4 is a sample 11, 10W RF power 4 and pulsed DC power 6 of aluminum plasma ion implanted at a pressure of 1.5mTorr using only a simple pulsed DC power 6 according to an embodiment of the present invention The OJ analysis result of measuring the distribution of aluminum element in the depth direction of the sample 11 into which aluminum plasma ions are injected at a pressure of 0.9 mTorr using the superimposed RF-DC coupling power 8 is shown.

By comparing the aluminum distribution of the aluminum plasma ion implanted sample 11 with reference to Figure 4 it can be seen clearly the difference. That is, compared with the sample 11 ion-implanted at 1.5 mTorr using only the pulsed DC power 6, the RF-DC combined power 8 having the 10W RF power 4 and the pulsed DC power 6 superimposed It can be seen that aluminum is ion-implanted to a point below the surface of the sample 11 implanted with ion at 0.9 mTorr. Since ion implantation is performed at 0.9mTorr, the process pressure lower than 1.5mTorr, the ion implantation depth is deep due to less energy loss of ions due to collision. In addition, as shown in Figure 4 also shows a difference in the amount of aluminum ion implanted during the same time. This is because when the RF power 4 is superimposed as described above, since the discharge starts as soon as the pulsed DC power 6 is supplied without the discharge delay phenomenon, the density of the plasma is relatively high. This means that the rate of ion implantation can be increased and the ion implantation process can be performed in a shorter time.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it is within the scope of the present invention.

Claims (14)

A vacuum chamber in which the inside maintains a vacuum state; A magnetron deposition source coupled to the vacuum chamber to generate a pulsed plasma into the vacuum chamber; A conductive sample mounting table installed at a position opposite to the magnetron deposition source in the vacuum chamber to mount a sample thereon; And RF-DC coupling unit for supplying RF-DC combined power of RF power and pulse DC power superimposed to the magnetron deposition source by combining the input pulse DC power and RF power Plasma ion implantation device comprising a. The method of claim 1, RF-DC combined power overlapping the RF power and the pulsed DC power has a density value of 10W / cm ² ~ 10kW / cm ² plasma ion implantation device. The method of claim 2, The power density of the RF power superimposed on the pulsed DC power is 0.1W / cm ² ~ 2W / cm ² plasma ion implantation device. The method of claim 3, Plasma ion implantation further comprises a high voltage pulse power supply for accelerating the pulsed plasma generated from the magnetron deposition source to the sample side and supplying a high voltage pulse synchronized to the pulse DC power input to the RF-DC coupling unit to the sample mounting table Device. The method of claim 4, wherein The operating frequency of the high voltage pulse generated from the high voltage pulse power supply unit is 1Hz to 10kHz, the same frequency as the RF-DC combined power superimposed RF power and pulsed DC power supplied to the magnetron deposition source, pulse width is 1usec ~ 200usec The negative ion pulse high voltage is -1kv to -100kV, the plasma ion implantation apparatus. The method of claim 1, A gas supply unit supplying a gas to be plasmaized into the vacuum chamber; A gas control unit disposed in a gas supply path between the gas supply unit and the vacuum chamber to adjust a pressure of a gas supplied from the gas supply unit into the vacuum chamber to maintain a set pressure inside the vacuum chamber; A first vacuum valve installed in a gas supply path between the gas control unit and the vacuum chamber; A vacuum pump for maintaining a vacuum in the vacuum chamber, and A second vacuum valve installed in a gas discharge path between the vacuum pump and the vacuum chamber Plasma ion implantation device further comprising. The method of claim 6, And a set pressure within the vacuum chamber is 0.1 mTorr to 2 mTorr. The method of claim 1, RF power supply for generating RF power, and RF matching unit coupled between the RF power supply unit and the RF-DC coupling unit for RF impedance matching Plasma ion implantation device further comprising. The method of claim 1, Pulse current measuring instrument for measuring plasma ion implantation current, A pulse voltage meter for measuring plasma ion implantation voltage, and A monitoring unit connected to the pulse current meter and the pulse voltage meter, respectively, to monitor plasma ion implantation current and voltage; Plasma ion implantation device further comprising. Placing the sample on the conductive sample mount in the vacuum chamber; Maintaining the interior of the vacuum chamber in a vacuum state using a vacuum pump; Supplying a gas to be plasmaized in the vacuum chamber and maintaining an internal pressure; Supplying an RF-DC coupled power in which RF power and pulsed DC power are superimposed on the magnetron deposition source to operate the magnetron deposition source; Synchronizing and supplying a negative high voltage pulse to a conductive sample holder at the same frequency as the pulsed DC power for operating the magnetron deposition source; Injecting ions into the surface of the sample by accelerating the high-density solid element plasma ions generated from the magnetron deposition source toward the sample by using a negative high voltage pulse supplied to the conductive sample mount Plasma ion implantation method comprising a. The method of claim 10, The pressure in the vacuum chamber is 0.1mTorr ~ 2mTorr plasma ion implantation method. The method of claim 10, RF-DC combined power superimposed the RF power and pulsed DC power has a density value of 10W / cm ² ~ 10kW / cm ² , the frequency is 1Hz ~ 10kHz, the pulse width is 1usec ~ 200usec plasma ion implantation method. The method of claim 12, RF power superimposed on the pulsed DC power is 0.1W / cm ² ~ 2W / cm ² plasma ion implantation method. The method of claim 13, The operating frequency of the high voltage pulse is 1 Hz to 10 kHz, which is the same frequency as the RF-DC combined power superimposed with the RF power supplied to the magnetron deposition source and the pulsed DC power, and the pulse width is 1usec to 200usec, and is negative. Pulse high voltage is -1kv to -100kV plasma ion implantation method.

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