TW201522676A - Sputtering film formation device and sputtering film formation method - Google Patents

Abstract

The present invention is a sputtering film formation device in which a high-voltage cathode voltage is applied to a cathode electrode to generate plasma between a target (10) and a substrate (12), thereby forming a film on the substrate (12) through a mask (11). The sputtering film formation device is equipped with a pulse bias power source (6) which enables the application of a pulse-like negative voltage to the mask (11) in the process of forming the film on the substrate (12). This constitution enables the mask to be washed while forming the film.

Description

Sputtering film forming device and sputtering film forming method

The present invention relates to a sputtering film forming apparatus for forming a film on a substrate disposed opposite to a target via a cover, and more particularly to a sputtering film forming apparatus capable of performing a film cleaning while being formed into a film and splashing A film forming method.

In the conventional film forming apparatus, the film forming apparatus including the cover cleaning function is formed in a film forming chamber in a reduced pressure state, and the organic compound is vapor-deposited by the cover, and the film forming chamber is not subjected to atmospheric pressure but to the cover. The high-frequency voltage is applied to excite the gas introduced into the film forming chamber to generate a plasma to remove the organic compound attached to the cover (see, for example, Japanese Laid-Open Patent Publication No. 2012-197518).

However, in the conventional film forming apparatus, since the cover cleaning is suitably performed after the film formation on the substrate, the film cannot be formed during the cleaning of the cover, and the production amount of the film formation substrate is lowered, which is a problem.

Therefore, the present invention has been made in view of such a problem, and an object thereof is to provide a sputtering film forming apparatus and a sputtering film forming method which can perform a cover cleaning while forming a film.

In order to achieve the above object, the sputtering film forming apparatus according to the first aspect of the invention is characterized in that: a cathode voltage of a high voltage is applied to a cathode electrode to generate a plasma between a target and a substrate, and a film is formed on the substrate via a cover; There is a pulse bias power supply, and a pulsed negative voltage can be applied to the cover during film formation on the substrate.

Further, the sputtering method of the second invention is a method in which a cathode voltage of a high voltage is applied to a cathode electrode to generate a plasma between a target and a substrate, and a film is formed on the substrate via a cover; A pulsed negative voltage is applied to the cover during film formation of the substrate.

According to the present invention, during the film formation of the substrate by applying a high voltage cathode voltage to the cathode electrode, the film deposited on the surface of the cover is knocked with a cation of an inert gas by applying a pulsed negative voltage to the cover. Click to remove. Therefore, the cover can be washed while the film is formed, and the throughput of the film formation substrate can be improved.

1‧‧‧vacuum room

2‧‧‧target holder

3‧‧‧Substrate holder

4‧‧ ‧ blocking

5‧‧‧High frequency power supply

6‧‧‧pulse bias power supply

7‧‧‧filming room

8‧‧‧ gas inlet

9‧‧‧Exhaust port

10‧‧‧ target

11‧‧‧ Cover

12‧‧‧Substrate

13‧‧‧ Bypass capacitor

14‧‧‧Shielding members

15‧‧‧ openings

16‧‧‧ bias electrode

17‧‧‧Restricted resistance

18‧‧‧cation

19‧‧‧ Sputtering particles

20‧‧‧ opening pattern

21‧‧‧Transparent conductive film

22‧‧‧DC power supply

23‧‧‧Resistance

Fig. 1 is a front view showing a schematic configuration of a first embodiment of a sputtering film forming apparatus of the present invention.

Fig. 2 is a flow chart for explaining a sputtering film formation method according to the first embodiment.

Fig. 3 is a timing chart showing the bias application timing of the first embodiment.

Fig. 4 is a view for explaining film formation in a seasoning period according to the first embodiment, wherein (a) shows the start of film formation, and (b) shows a state in which film formation is advanced.

Fig. 5 is an explanatory view showing a cleaning of a cover which is sputter-deposited in the first embodiment.

Fig. 6 is a view for explaining the film formation restart in the sputtering film formation of the first embodiment, wherein (a) shows film formation re-starting, and (b) shows film formation and advancement.

Fig. 7 is a front view showing a schematic configuration of a second embodiment of the sputtering film forming apparatus of the present invention.

Fig. 8 is a timing chart showing the bias application timing of the second embodiment.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. Fig. 1 is a front view showing a schematic configuration of a first embodiment of a sputtering film forming apparatus of the present invention. The sputtering film forming apparatus is an RF sputtering apparatus which applies a high-frequency voltage to a target holder to generate a plasma between the target and the substrate, and forms a film on the substrate via the cover. The vacuum chamber 1 is provided. The target holder 2, the substrate holder 3, the shutter 4, the high frequency power source 5, and the pulse bias power source 6.

The vacuum chamber 1 is a sealed container in which the film forming chamber 7 is formed, and includes a gas introduction port 8 and an exhaust port 9. Further, the inside of the film forming chamber 7 can be maintained at a constant degree of vacuum by evacuating the air or the sputtering gas in the film forming chamber 7 by a vacuum pump (not shown) provided in connection with the exhaust port 9. Again The gas introduction port 8 is a gas cylinder (not shown) in which an inert gas such as an argon (Ar) gas is connected to a pipe, and a sputtering gas can be introduced into the film formation chamber 7.

The target holder 2 is disposed in the film forming chamber 7 of the vacuum chamber 1. The target holder 2 is a fixed holding target 10, and is formed of a metal material in a state of being electrically insulated from the vacuum chamber 1. Further, the target holder 2 may be provided with a water path for introducing the cooling water for cooling the target 10 from the outside to the inside as necessary.

The substrate holder 3 is disposed in the film forming chamber 7 of the vacuum chamber 1 in opposition to the target holder 2 . The substrate holder 3 is formed of a metal material in a state in which the cover 11 made of, for example, a resin film having a plurality of opening patterns is adhered to the film formation surface of the substrate 12 while the substrate 12 is held.

Further, the cover 11 is not limited to being formed of a non-conductive material such as a resin film, and may be a conductive metal cover. In this case, when the film to be formed is a conductive film, either a non-conductive cover or a conductive metal cover can be used. Further, when the film to be formed is a non-conductive film, a conductive metal cover or a composite cover coated with a conductive film on the target side surface of the non-conductive cover can be used. In the description of the present embodiment, a case where the film formed is a conductive film and the cover 11 is a non-conductive resin film is described.

The target holder 2 and the substrate holder 3 can be disposed in various ways in the film forming chamber 7 of the vacuum chamber 1. For example, the target holder 2 and the substrate holder 3 may be arranged in an up-and-down direction or in a left-right direction. In the case where the cover 11 is a film as in the embodiment, the target holder 2 and the substrate holder 3 are disposed to face up and down with respect to the vacuum chamber 7 so that the substrate holder 3 is positioned below. The vertical axis is preferably tilted in the opposite direction. Thereby, since the film cover 11 hangs down by its own weight, the cover 11 can be adhered to the film formation surface of the substrate 12.

A shutter 4 is provided between the target holder 2 and the substrate holder 3. The shutter 4 is for controlling the start and end timing of film formation, and is provided to open and close the passage of the sputter particles 19 (see FIG. 4) flying from the target 10 toward the substrate 12. That is, if the shutter 4 is moved in the direction of the arrow A shown in Fig. 1 to open the passage of the sputtered particles 19, film formation is started, and if the shutter 4 is moved in the direction of the arrow B shown in the figure, the passage of the sputtered particles 19 is closed. Then the film formation is finished. Thereby, the film thickness of the film pattern of the film formation can be controlled. Further, a state in which the passage of the sputter particles 19 is closed by the shutter 4 is referred to as "the shutter 4 is closed", and a state in which the passage of the sputter particles 19 is opened is referred to as "the shutter 4 is opened".

The target holder 2 is electrically connected to each other and is provided with a high-frequency power source (RF power source) 5. The high-frequency power source 5 supplies high-frequency power of 13.56 MHz to the target holder 2 to apply a high-frequency voltage (RF voltage) to the target holder 2 to generate plasma between the target 10 and the substrate 12, which is useful for adjusting high. The high frequency matcher omitted from the illustration of the frequency power. In this case, the target holder 2 side serves as a cathode electrode, and the substrate holder 3 side serves as a ground electrode (anode electrode). Further, reference numeral 13 in Fig. 1 is a bypass capacitor connected in series with the target holder 2, and reference numeral 14 is a shield which prevents the anode ions from colliding with a portion other than the target 10 portion opposite to the substrate 12, for example, the target holder 2. The member is provided with an opening 15 corresponding to a central region of the target 10.

A pulsed bias power source 6 is provided on the surface of the target 10 of the cover 11 to be energized. The pulse bias power source 6 and the cathode voltage are driven in synchronization, and when the cathode voltage is positive, the ON drive is performed to output a pulse-shaped negative voltage, and the cover 11 is biased. In this case, as shown in FIG. 1, the pulse bias power source 6 has a bias electrode 16 (contacting the surface of the cover 11) and a limiting resistor 17 (inserted between the bias electrode 16 and the pulse bias power source 6). To limit the flow through the current) in series.

Next, a sputtering film forming method using the sputtering film forming apparatus constructed in this manner will be described with reference to the flowchart of FIG. 2.

First, in step S1, preparation for film formation is performed. Specifically, the vacuum of the film forming chamber 7 of the vacuum chamber 1 is broken, and the target 10 of the ITO (composite oxide film forming material containing indium-tin as a main component) is mounted on the target holder 2 in the film forming chamber 7.

Next, the substrate 12 is placed on the substrate holder 3, and the cover 11 is placed in close contact with the film formation surface of the substrate 12. Thereafter, the bias electrode 16 associated with the pulse bias power source 6 is in contact with the surface of the cover 11.

In step S2, preparation for film formation is started. In detail, once the mounting of the target 10 and the substrate 12 is completed, the vacuum chamber 1 is closed. Then, the exhaust valve (not shown) provided on the exhaust port 9 side of the vacuum chamber 1 is slowly opened, and the air in the film forming chamber 7 is exhausted by a vacuum pump. Further, at this time, the gas introduction valve (not shown) provided on the side of the gas introduction port 8 is in a closed state. In addition, the shutter 4 is also in a closed state.

Once the degree of vacuum in the film forming chamber 7 reaches a predetermined value, the gas introduction valve is opened to introduce, for example, a mass flow controller into the Ar gas adjusted to a constant flow rate. Then, by adjusting the exhaust valve The exhaust gas amount of the exhaust pump is adjusted so that the total gas pressure in the film forming chamber 7 is adjusted to a predetermined value.

In step S3, film formation of the transparent conductive film 21 is performed. Specifically, when the gas pressure in the film forming chamber 7 reaches a predetermined value, the high-frequency power source 5 is activated, and a high-frequency (RF) voltage shown in FIG. 3(a) of a predetermined value is applied to the target 10. This high frequency power is adjusted by the high frequency matcher and the power output.

When a predetermined high-frequency power is applied to the target 10, the Ar gas in the film forming chamber 7 is ionized, and plasma is generated between the target 10 and the shutter 4. Then, pre-sputtering is performed for a certain period of time to remove impurities on the surface of the target 10, and then the shutter 4 is opened, and the substrate 12 is sputter-deposited.

Hereinafter, the sputtering film formation of the present invention will be described in detail.

When the RF voltage shown in FIG. 3(a) is applied to the target holder 2, since the bypass capacitor 13 is provided, the cathode voltage becomes a sinusoidal waveform shifted to the negative side as shown in FIG. 3(b). Then, as shown by the oblique line in the figure, sputtering of the target is performed while the cathode voltage is negative, and film formation on the substrate 12 is performed. From the start of sputtering to a certain period of time (during the seasoning shown in (c)), a transparent film having a sufficient film thickness that can be biased from the pulse bias power source 6 is not deposited on the surface of the cover 11. 21, even if the pulse bias power source 6 is activated, no bias is applied to the surface of the cover 11. Therefore, in the present embodiment, the pulse bias power supply 6 during the aging period is 0V.

In the above aging period, as shown in FIG. 4(a), the ionized Ar gas cation 18 is pulled toward the target 10 side when the cathode voltage is negative, and collides with the target 10 as shown by the arrow to fly out. Plating particles 19. As a result, the sputtered particles 19 flying out of the bomb fly toward the substrate 12 side, and as shown in FIG. (b), the film is adhered to the surface of the substrate 12 by the opening pattern 20 of the cover 11 to form a film. At the same time, the surface of the cover 11 is also coated with the sputter particles 19 to deposit the transparent conductive film 21. In this manner, as shown in FIG. 3(b), film formation is performed during target sputtering in which the cathode voltage is negative.

Once the aging period has elapsed, the pulse-biased power source 6 is activated as shown in Fig. 3(c). Further, during a period in which the cathode voltage is positive and sputtering is stopped (during the target sputtering stop period shown in FIG. (b)), the pulse bias power source 6 outputs a negative voltage to the transparent conductive film deposited on the surface of the cover 11. 21 applies a pulsed bias (-Vb). Thereby, as shown in FIG. 5, the ionized Ar gas cation 18 is pulled toward the side of the cover 11, and the transparent conductive film 21 deposited on the surface of the cover 11 is struck as shown by the arrow to perform ion bombardment ( The cover is washed).

Next, as shown in FIG. 3(b), if the positive period of the cathode voltage is completed and the cathode voltage is switched to be negative, as shown in FIG. 3(c), the pulse bias power source 6 is controlled in synchronization with the cathode voltage. The applied voltage to the cover 11 becomes 0 V (the pulse bias power supply 6 is driven OFF). As a result, as shown in FIG. 6(a), the conventional sputter film 11 is used again to form a film, and as shown in FIG. 6(b), the transparent conductive film 21 is deposited on the surface of the substrate 12 and the cover 11.

Thereafter, the sputtering film formation and the cover 11 are alternately washed, and once the predetermined time has elapsed, the shutter 4 is closed to complete the film formation. Furthermore, the high frequency power source 5 and the pulse bias power source 6 are turned off.

Next, in step S4, the substrate is taken out. Specifically, the exhaust valve and the gas introduction valve are closed, and the vent valve (not shown) is opened to break the vacuum in the film forming chamber 7 of the vacuum chamber 1. Thereby, the film forming chamber 7 can be opened and the substrate 12 can be taken out. Further, when the substrate 12 is taken out, the bias electrode 16 is retracted from the inside of the cover 11 to the outside.

Fig. 7 is a front elevational view showing a schematic configuration of a second embodiment of the sputtering film forming apparatus of the present invention. Here, a description will be given of a portion different from the first embodiment.

In the first embodiment, in place of the high-frequency power source 5, the DC power supply 22 is provided instead, and the negative electrode side of the DC power source 22 is connected to the target holder 2 (cathode electrode) via the resistor 23, and the positive electrode side is connected. The substrate holder 3 (anode electrode) is a DC sputtering device. In this case, the target material used is limited to a conductive material.

Further, the pulse bias power supply 6 of the second embodiment can output a pulsed negative voltage of a predetermined period in a state where a target voltage (-Vc) is applied to the target holder 2, and apply a voltage absolute value to the cover 11 to the cathode. The voltage (-Vc) is a large bias (-Vb) (ie, Vc < Vb).

According to the second embodiment, as shown in Fig. 8(a), a negative DC voltage (cathode voltage) of several hundred volts is applied to the cathode electrode at the time of film formation, and plasma is generated between the target 10 and the substrate 12. The substrate 12 is formed into a film.

Specifically, in the same manner as in the above-described first embodiment, the target 10 is struck by the argon cation 18 generated by the slurry formation of the Ar gas, whereby the sputtered particles 19 which are ejected by the bomb are deposited on the substrate 12. Film formation of a conductive film.

Further, as shown in FIG. 8(b), the voltage applied to the cover 11 during the aging period after the start of film formation is 0 V, and a pulse-like negative voltage of a certain period is output after the aging period elapses. Applying a bias voltage (-Vb) to the cover 11 that has a larger absolute value than the cathode voltage (-Vc) (ie, Vc < Vb). As a result, when the pulsed bias (-Vb) is applied to the cover 11, the argon cation 18 is pulled to the side of the cover 11, and the conductive film deposited on the surface of the cover 11 is struck in the same manner as in the first embodiment. For ion bombardment (washing of the cover).

As such, in the sputtering film forming apparatus of the present invention, in the film formation process in which the cathode voltage of the cathode electrode is applied with a high voltage, a pulsed negative voltage is applied to the shell 11 to deposit on the surface of the shell 11. The film is removed by tapping with a cation 18 of an inert gas. Therefore, the cover 11 can be cleaned while being formed into a film, and the throughput of the film formation substrate can be improved.

Further, in the above-described embodiment, the case where the pulse bias power supply 6 is stopped during the aging period and the applied voltage of the cover 11 is 0 V has been described. However, the present invention is not limited thereto, and the high frequency power supply may be activated. 5 or the DC power supply 22 simultaneously activates the pulse bias power supply 6 to apply a negative voltage to the cover 11 for a certain period. However, until the surface of the cover 11 is entirely deposited with a conductive film having a sufficient thickness to allow the bias voltage to be energized, even if the pulse-bias power supply 6 is activated, the conductive film cannot be biased, and the cover cleaning function cannot be performed.

Further, in the above-described embodiment, the case where the film formed on the substrate 12 is a conductive film has been described. However, when the cover 11 is a conductive metal cover or the metal cover is adhered to the resin film, In the case of a composite cover, the film formed may also be a non-conductive film.

Further, in the above embodiment, the sputter deposition film forming apparatus of the batch type has been described. However, the present invention is not limited thereto, and may be an in-line sputtering film forming apparatus. In this case, the film forming chamber 7 is provided with a load lock chamber on the upstream side in the transport direction of the substrate 12, and an unloading chamber on the downstream side. In this case, first, the gate valve on the upstream side of the load lock chamber is opened to carry the substrate 12 into the load lock chamber. Next, after the gate valve is closed to exhaust the load lock chamber, the gate valve on the downstream side of the load lock chamber is opened to carry the substrate 12 into the film forming chamber 7, and the substrate holder 3 is disposed. Thereafter, the downstream side gate valve is closed, and the cover body 11 of the cover holder held in the film forming chamber 7 is loaded and placed on the substrate 12, and the bias electrode 16 is brought into contact with the surface of the cover 11. Thereby, the above RF sputtering film formation can be performed. On the other hand, once the film formation is completed, the cover 11 is unloaded after the bias electrode 16 is retracted. Then, after the film forming chamber 7 is exhausted, the gate valve on the downstream side of the film forming chamber 7 is opened to carry the substrate 12 out to the unloading chamber. Thereafter, the gate valve on the downstream side of the film forming chamber 7 is closed, and the vacuum in the unloading chamber is broken, making it possible to take out the substrate 12.

1‧‧‧vacuum room

2‧‧‧target holder

3‧‧‧Substrate holder

4‧‧ ‧ blocking

5‧‧‧High frequency power supply

6‧‧‧pulse bias power supply

7‧‧‧filming room

8‧‧‧ gas inlet

9‧‧‧Exhaust port

10‧‧‧ target

11‧‧‧ Cover

12‧‧‧Substrate

13‧‧‧ Bypass capacitor

14‧‧‧Shielding members

15‧‧‧ openings

16‧‧‧ bias electrode

17‧‧‧Restricted resistance

Claims (13)

A sputtering film forming apparatus which applies a high voltage cathode voltage to a cathode electrode to generate a plasma between a target and a substrate, and forms a film on the substrate via a cover; and is characterized in that a pulse bias power source is provided, During the film formation of the substrate, a pulsed negative voltage can be applied to the cover. The sputtering film forming apparatus of claim 1, wherein the cathode voltage is a high frequency voltage; the pulse bias power source is driven synchronously with the cathode voltage, and the pulsed negative voltage is output when the cathode voltage is positive. A negative voltage is applied to the cover. The sputtering film forming apparatus of claim 1, wherein the cathode voltage is a direct current voltage; and in the state in which the cathode voltage is applied, the pulse bias power source outputs the pulsed negative voltage of a certain period to the cover. The absolute value of the applied voltage of the body is greater than the negative voltage of the cathode voltage. The sputtering film forming apparatus according to any one of claims 1 to 3, wherein the film formed on the substrate is a conductive film; and the cover system is formed of a non-conductive material. A sputter deposition apparatus according to any one of claims 1 to 3, wherein the cover system is formed of a conductive material. A sputtering method for forming a film by applying a high voltage cathode voltage to a cathode electrode to generate a plasma between a target and a substrate, and forming a film on the substrate via a cover; wherein a film formation process is performed on the substrate A pulsed negative voltage is applied to the cover. The method of sputtering film formation according to claim 6, wherein the cathode voltage is a high frequency voltage, and the pulsed negative voltage is applied to the cover when the cathode voltage is positive. The method of sputter film formation according to claim 6, wherein the cathode voltage is a direct current voltage, and in the state where the cathode voltage is applied, the pulse value of the voltage value is larger than the cathode voltage by a certain period. A negative voltage is applied to the cover. The sputtering film forming method according to any one of claims 6 to 8, wherein the cover body starts to apply the pulsed negative voltage after a predetermined time elapses from the start of film formation. The sputtering film forming method according to any one of claims 6 to 8, wherein the film formed on the substrate is a conductive film; the cover system is formed of a non-conductive material. The method of sputtering film formation according to claim 9, wherein the film formed on the substrate is a conductive film; and the cover system is formed of a non-conductive material. The method of sputter film formation according to any one of claims 6 to 8, wherein the cover system is formed of a conductive material. A method of sputter deposition film formation according to claim 9, wherein the cover system is formed of a conductive material.