TWI539022B - Sputtering apparatus and sputtering film forming method - Google Patents

Description

Sputtering device and sputtering film forming method

The present invention relates to a sputtering apparatus and a sputtering film forming method. In particular, it is implemented in a substrate transfer type continuous sputtering film forming apparatus having three or more magnetron cathodes, and is suitable for reciprocating a magnet with a magnetron cathode while sequentially sputtering the substrate by sputtering. A sputtering apparatus for forming a film and a sputtering film forming method.

Patent Document 1 discloses a device in which a magnetron cathode (magnetron sputtering unit) having a magnet is disposed on the back side of a target, and the phase of the reciprocating movement of each magnet is adjusted so that the film thickness along the conveying direction is increased. A uniform method. The thick region and the thin region are alternately generated on the film formed on the substrate by the first magnetron sputtering unit, and the speed of the substrate transport direction (hereinafter referred to as the forward direction) of the reciprocating movement of the magnet is changed. In the reverse direction of substrate conveyance (hereinafter referred to as reverse direction), the ratio of the length of the thick region of the film formed on the substrate to the length of the thin region is about 1:2, and film formation is performed. The second magnetron sputtering unit and the third magnetron sputtering unit are also reciprocally moved to form a film in the same manner as the first magnetron sputtering unit.

Forming a thick layer on the substrate by the first magnetron sputtering unit The region of the film overlaps the region where the second magnetron sputtering unit and the third magnetron sputtering unit form a thin film. In the region where the thin film is formed on the substrate by the first magnetron sputtering unit, the second magnetron sputtering unit and the third magnetron sputtering unit are formed to be thin and the other is thick. The area. In this way, when the phase of the second magnetron sputtering unit and the third magnetron sputtering unit reciprocating to the magnet of the first magnetron sputtering unit is adjusted, the three magnetron sputtering unit stacks are used. When the layer is formed into a film, the film thickness in the conveyance direction becomes uniform.

[Previous Technical Literature] [Patent Document]

[Patent Document 1]: International Publication No. 2009/093598

In order to reciprocate the magnet, it is necessary to decelerate the magnet of a certain speed on the front side of the stroke end, stop at the stroke end, and then accelerate in the reverse direction. Although the stop time can be reduced, it is necessary to slow down and accelerate. In the method of using the three magnet sputtering units of Patent Document 1 to make the film thickness uniform in the substrate transport direction, since the magnets are decelerated and accelerated at both ends of the reciprocating stroke of the magnet, the film on the substrate is transported. Thickness uniformity is not very good.

The reasons are as follows. A method of uniformizing the film thickness by laminating a film formed by three magnetron sputtering units is performed on a substrate The position is a stack of three layers of (thick film) + (thin film) + (thin film), and the order must be combined anyway. Here, the (thick film) is a film in which a magnet is simultaneously moved in a forward direction at a constant speed, and a (thin film) is a film in which a magnet is moved in a reverse direction at a constant speed. In Patent Document 1, the length of the region (thick film) in the conveyance direction on the substrate and the length of the region (thin film) are 1:2, so that any position on the substrate can be used. Combination (thick film) + (thin film) + (thin film).

However, in actuality, the film thickness of the magnet formed in the deceleration or acceleration near the end of the reciprocating movement is not the above-mentioned thick film or thin film, but the intermediate film. For example, when the magnet of the first magnetron sputtering unit moves in the reverse direction and the film is formed at the time of deceleration on the front side of the stroke end, the film on the substrate becomes (slightly thin film). When the second magnetron sputtering unit is formed, the magnet moves in the forward direction and decelerates on the front side of the stroke end, and the film on the substrate becomes a (slightly thick film). Similarly, when the third magnetron sputtering unit is formed, the magnet moves in the reverse direction and moves at a constant speed in the center of the stroke, and the film on the substrate becomes (thin film).

That is, it is a laminate of three layers of (slightly thin film) + (slightly thick film) + (thin film). At this time, the film thickness is thinner than the lamination of the three layers of the above (thick film) + (thin film) + (thin film). Therefore, the film thickness uniformity in the conveyance direction on the substrate is not so good. When the film thickness of the film formed by the third magnetron sputtering unit is (slightly thin film), the film thickness uniformity in the conveyance direction is good, but the deceleration or acceleration of the magnet is only at the both ends of the stroke. Two, so it is impossible to slow down in a three-layer stack or Film formation is carried out during acceleration.

The present invention has been made to solve the above problems, and an object thereof is to provide a sputtering apparatus and a sputtering film forming method which improve uniformity of film thickness and utilization of a target.

A sputtering apparatus according to the present invention includes: a vacuum container; a substrate conveying unit configured to convey the substrate in the vacuum container; and at least three target holding portions arranged in a conveying direction of the substrate to be held for a target for sequentially forming a substrate to be transported by the substrate transporting portion; a magnet portion disposed on a back side of each of the target holding portions; and a magnet driving portion for driving The magnet unit and the control unit control the substrate transport unit and the magnet drive unit to perform the magnets in a predetermined cycle when the target holding unit holds the target and performs a film formation process. The portion moves from the stroke end of the conveyance direction to a first movement that is reversed from the conveyance direction and stops at the first specific position, and moves the reverse direction from the first specific position and stops at the second specific position after the first movement. The second movement and the third movement that is stopped from the reverse stroke end to the conveyance direction and stopped at the stroke end of the conveyance direction, and each of the first and second movements In the third movement, the magnet portion on the substrate made of the relative movement distance in the conveyance direction become equal.

The sputtering film forming method according to the present invention is a sputtering film forming method using a sputtering apparatus, the sputtering apparatus comprising: a vacuum container; The transport unit is configured to transport the substrate in the vacuum container; at least three target holding portions arranged in the transport direction of the substrate to hold the substrate to be transported by the substrate transport unit a target for forming a film; a magnet portion disposed on a back side of each of the target holding portions; and a magnet driving portion for driving the magnet portion, wherein the sputtering film forming method is characterized by When the target holding member holds the target and performs a film forming process, the magnet portion is moved from the stroke end in the conveyance direction to the conveyance direction in the first specific position in a predetermined cycle. a first movement that is stopped, and a second movement that is stopped from the first specific position and that is stopped at the second specific position after the first movement, and moves from the reverse stroke end to the conveyance direction. The third movement of the stroke end of the direction is stopped, and in the first, second, and third movements, the distance at which the substrate moves relative to the magnet portion in the conveyance direction is equal.

A sputtering apparatus and a sputtering film forming method which increase the uniformity of the film thickness and the utilization of the target can be provided.

Other features and advantages of the present invention will be apparent from the following description. Further, in the attached drawings, the same reference numerals are assigned to the same or similar configurations.

1‧‧‧Substrate

2‧‧‧ chamber

3‧‧‧Transport roller

4‧‧‧ Target

5, 5a, 5b, 5c‧‧‧ target shielding

6, 6a, 6b, 6c‧‧‧ cathode

7, 7a, 7b, 7c‧‧‧ magnets

8, 8a‧‧‧ cathode insulation

9, 9a, 9b, 9c‧‧‧ cathode partition (target retaining unit)

10, 10a, 10b, 10c‧‧‧ magnetron sputtering unit

11a, 11b, 11c‧‧‧ Magnet Moving Department

21‧‧‧Substrate drive unit

25‧‧‧Control Department

100‧‧‧filming room

The attached drawings are included in the manual, which form part of the table. The embodiments of the invention are shown to illustrate the description and the principles of the invention.

Fig. 1 is a schematic cross-sectional view showing a film forming chamber of an in-line continuous sputtering film forming apparatus according to an embodiment of the present invention.

Fig. 2 is a schematic view showing the movement of the magnet in the substrate conveyance direction of the magnetron sputtering unit according to an embodiment of the present invention.

Fig. 3 is a velocity diagram showing the change in speed of one cycle of the movement of the magnet of Fig. 2.

Fig. 4A is a schematic view showing the positional relationship between the magnet 7 and the substrate during the movement of the magnet of Fig. 2.

Fig. 4B is a schematic view showing the positional relationship between the magnet 7 and the substrate during the movement of the magnet of Fig. 2.

Fig. 4C is a schematic view showing the positional relationship between the magnet 7 and the substrate during the movement of the magnet of Fig. 2.

Fig. 5 is a schematic view showing the movement of magnets of three magnetron sputtering units relating to an embodiment of the present invention.

Fig. 6 is a schematic view showing the relative speed and film thickness of a magnet which is based on a substrate conveyed by a one-line continuous sputtering film forming apparatus according to an embodiment of the present invention.

Fig. 7 is a view showing the relative velocity V _ms of the magnet 7 to the substrate when the magnet of the magnetron sputtering unit according to an embodiment of the present invention is viewed.

Figure 8 is a graph showing the speed of the magnet 7 to the cathode 6 of the magnetron sputtering unit associated with an embodiment of the present invention.

Fig. 9 is an explanatory view showing the relative speed of a magnet to a substrate relating to an embodiment of the present invention.

Fig. 10 is an explanatory view showing the starting time of the magnets of the three magnetron sputtering units relating to one embodiment of the present invention.

Fig. 11 is an explanatory view showing the distance in the substrate conveyance direction between the cathode centers of the three magnetron sputtering units 10a, 10b, and 10c according to an embodiment of the present invention.

Fig. 12 is a view showing the distribution of the transport direction of the film stacked on the substrate by the sputtering method of the embodiment of the present invention.

Fig. 13 is a view showing the distribution of the transport direction of the film stacked on the substrate in the film forming conditions different from those in Fig. 11.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the present invention is not limited to the invention, and various modifications may be made without departing from the spirit and scope of the invention. In the embodiment, although the sputtering apparatus is exemplified by a device having three magnetron sputtering units in one film forming chamber, the present invention is applicable to the substrate carrying path along the sputtering apparatus. It has a device with more than 3 magnetron sputtering units.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a schematic cross-sectional view showing the structure of a film forming chamber of a substrate transfer type continuous sputtering film forming apparatus which can be applied to the present invention. Generally, the load lock chamber, the buffer chamber, the film forming chamber 100, and the unloading lock The plurality of chambers such as the chamber are connected by a gate valve to form a substrate-transport type one-line continuous sputtering film forming apparatus. However, in the first drawing, only the film forming chamber 100 is shown.

As shown in Fig. 1, the film forming chamber 100 is composed of a chamber 2 (vacuum container), a substrate conveying portion, and three magnetron sputtering units 10a, 10b, and 10c (splashing) disposed above the chamber 2. The plating means). The substrate conveyance unit includes a conveyance roller 3 that conveys the substrate 1 provided in the chamber 2, and a substrate driving device 21 that rotates the conveyance roller 3. In the present embodiment, the substrate 1 is carried on the transport roller 3 in a horizontal state, and is transported in the right direction at a constant speed as shown in Fig. 1 . The chamber is evacuated by an exhaust pump (not shown), and a process gas is supplied by a gas pipe (not shown), for example, an argon (Ar) gas to be a specific pressure.

The three magnetron sputtering units as the sputtering means are the first magnetron sputtering unit 10a (first sputtering means) and the second magnetron sputtering unit 10b from the upstream side in the substrate conveyance direction. The (second sputtering means) and the third magnetron sputtering unit 10c (third sputtering means) are arranged, and the substrate conveyed by the substrate driving device 21 can be sequentially formed into a film. The configuration of the first magnetron sputtering unit 10a will be described with reference to three magnetron sputtering units. Each of the magnetron sputtering units 10a, 10b, and 10c has the same configuration. In the present embodiment, the targets 4a, 4b, 4c are the same material. The cathode partition wall 9a (target holding portion) of the magnetron sputtering unit 10a is disposed on the ceiling wall of the chamber 2 via the cathode insulating portion 8a. The cathode partition wall 9a is provided with a cathode 6a that supplies electric power by a power supply mechanism (not shown). Here, DC power is supplied to the cathode 6a.

The target 4a is held by the cathode 6a by a method such as bonding, and the cathode 6a and the target 4a are fixed to the cathode partition wall 9a in an integrated state. The target 4a is disposed to face the substrate conveyed by the substrate transfer device. The cathode 6a is referred to as a target backing plate or a support plate. Although not shown, a water path is provided inside the cathode 6a for cooling the target. In order to prevent sputtering from the surface of the target 4a, the target shield 5a is covered with a gap of 2 to 3 mm across the exposed surface of the target 4a side, the cathode 6a, and the cathode partition 9a.

A magnet 7a (magnet portion) is provided on the atmosphere side (the back side of the target 4a) on the side opposite to the cathode 6a of the cathode partition wall 9a. The magnet 7a is composed of a flat yoke and a permanent magnet, and is formed by setting the cathode 6a side as the center pole of the S pole and the cathode 6a side as the outer pole of the N pole. The magnetic lines of force formed by the magnet 7a form two tunnel-shaped loops near the surface of the target 4a. When discharging. A high density plasma is produced at the magnetic field loop near the surface of the target 4a.

The magnet 7a can be reciprocated by the magnet moving portion 11a (magnet driving portion) along the substrate conveying direction. The magnet moving portion 11a is constituted by a power transmission device such as a motor and a ball screw, and the magnet 7a can be moved to a position designated at a predetermined speed. The magnet 7a is reciprocated in a specific cycle with a specific stroke. The section of the speed control of the magnet 7a can be set to be trapezoidal driven by acceleration, constant speed, and deceleration. At this time, the magnet 7a is moved from the stopped state by the acceleration with a constant acceleration, then moves at a constant speed, and then moves at a constant acceleration and then stops again. The distance moved during this period becomes the vertical axis speed and the horizontal axis time. The area of the trapezoidal part of the velocity line diagram.

The three magnet moving portions 11a, 11b, and 11c and the substrate driving device 21 are controlled by the control unit 25. The speed at which the magnet reciprocates or the phase difference between the three magnets is determined by the substrate conveyance speed as will be described later. Therefore, the control unit 25 determines these values from the board conveyance speed by calculation, controls the magnet moving unit 11, and moves the magnet 7. That is, the control unit 25 can control the phase of the movement of the magnets 7a, 7b, and 7c in accordance with the timing of substrate conveyance.

Next, a method of sputtering film formation will be described. At the time of the film formation process, an argon (Ar) gas-like process gas is introduced into the chamber 2 so that the inside of the chamber 2 in which the exhaust gas is evacuated becomes a specific pressure, and is transported at a constant speed by the substrate transfer device. Substrate. The cooling water is supplied first in the water path of the cathode. The magnets 7a, 7b, and 7c (hereinafter, the symbol is 7) are reciprocated in the conveyance direction of the substrate, and the cathodes 6a, 6b, and 6c (hereinafter, the symbol is 6) are applied with a constant DC power, and magnetic is applied. The control tube is sputtered to form a film. In addition, when a specific component included in any one of the three magnetron sputtering units 10a, 10b, and 10c is included, the letter is removed and described. For example, when any of the magnets 7a, 7b, and 7c is an arbitrary magnet, the magnet 7 is used.

On the surface of the target 4, erosion occurs (erosion of the target) where the plasma becomes high density. The plasma becomes a high density, which is determined by the magnetic lines of force formed by the magnet 7. By moving the magnet 7 relative to the target 4, sputtering is performed to form a film, and a uniform depth is formed on the surface of the target 4, whereby the utilization ratio of the target can be improved. The life of the target 4 becomes longer, To reduce the frequency of target replacement.

When the magnet 7 is reciprocated along the substrate conveyance direction, the film thickness along the conveyance direction on the substrate may become uneven. V _t is set along the conveying speed, the conveying direction of reciprocation of the substrate 7 of the magnet case where the period is T, meet V _t. There is no problem in the case of a relatively fast reciprocating speed of T < 70 mm, and in other cases, it is V _t . In the case of T≧70mm, only one magnetron sputtering unit cannot form a uniform film in the conveying direction. Hereinafter, a method of sputtering a film forming method using three magnetron sputtering units 10a, 10b, and 10c for a sputtering film forming method in which a relatively slow magnet reciprocating speed is used will be described.

Fig. 2 shows an example of the movement of the magnet 7 of the magnetron sputtering unit in the substrate conveyance direction, and Fig. 3 shows a velocity diagram. Fig. 4A to Fig. 4C are schematic views showing the positional relationship between the magnet 7 and the substrate at this time. In this example, the stroke L (one-way) of the reciprocating movement of the magnet is 100 mm, and the period T of the reciprocating movement is set to 9 seconds. The detailed control method will be described later. The vertical axis of the graph of Fig. 2 is at a position where the substrate is transported, and the position where the center position of the magnet 7 overlaps with the center position of the cathode 6 is set to 0 mm, and the forward direction of the substrate conveyance direction is expressed as positive, and the reverse direction is reversed. Expressed as negative. The initial position of the magnet 7 is the +50 mm position of the forward stroke end (indicated by P0 in Fig. 2 and Fig. 4). From here on, the starting magnet 7 is moved in the reverse direction and is temporarily stopped at the 0 mm position (first specific position) of the stroke center (indicated by P1 in FIGS. 2 and 4). Hereinafter, the movement up to this point is referred to as a first movement (refer to FIG. 3(A)).

Then move backwards and move to the end of the reverse -50 mm (second specific position) (indicated by P2 in Fig. 2, Fig. 4A to Fig. 4C) and stopped again. Hereinafter, the movement up to this point is referred to as a second movement (refer to FIG. 3(B)). Next, the magnet is moved in the reverse direction and moved to the +50 mm position of the forward stroke end (the third specific position, and the second figure, FIG. 4A to FIG. 4C is indicated by P3) and stopped. Hereinafter, the movement up to this point is referred to as a third movement (refer to FIG. 4(C)). So far, 9 seconds is used for 1 cycle. After the third movement is completed, the position (P3) at which the magnet 7 is stopped is the first movement start position (P0). The magnet 7 repeats the first to third movements in a specific cycle (a 9-second cycle in the present embodiment). During the movement of the first, second, and third, the time of each stop is equal.

Fig. 3 is a velocity diagram showing the change in speed of one cycle of the movement of the magnet of Fig. 2. The horizontal axis represents time, and the vertical axis represents the velocity V _{mc of the} magnet to the cathode. The direction of the velocity takes a negative value in the direction of the substrate transport direction, and takes a positive value in the reverse direction. In addition, in the third figure, the magnet 7 is stopped (the speed is zero), and the symbol (P0 to P3) corresponding to the position in the second figure is described. The magnet 7 is reversed from the initial position (position P0), accelerates at a constant acceleration for a certain period of time, then moves at a constant speed in the reverse direction, and then decelerates at an equal acceleration in the reverse direction, and the speed becomes zero, and stops at the position P1. The shape of the speed line graph up to this point is trapezoidal. In the present embodiment, speed control generally referred to as trapezoidal driving (trapezoidal control) is employed. In terms of the motor drive control method, it is a general method. With the speed control up to this point, the magnet moves from +50 mm at the stroke end of the forward position (position P0) shown in Fig. 2 to the 0 mm position (first specific position, position P1) of the stroke center. After that, it stops at a certain time, so the speed is kept at 0 mm/s. This is the first move.

Then, the reverse acceleration, constant velocity, and deceleration trapezoidal driving and stopping are repeated in the same manner as the speed change up to this point. Up to this point, it is moved from the reverse stroke end shown in Fig. 2 to the -50 mm position (second specific position, position P2). This is the second move. Next, in the forward direction (positive speed in FIG. 3), trapezoidal driving and stopping (third specific position, position P3) of acceleration, constant speed, and deceleration are performed. However, the speed of the constant velocity and the time of the constant velocity are different from those of the reverse. The absolute value of the constant speed is less than the reverse direction, and the time of the constant speed becomes longer. This is the third move. Further, in the present embodiment, the position (position P3) at which the third movement ends is coincident with the start position (position P0) of the first movement.

Although an example of the movement of the magnet 7 of the magnetron sputtering unit has been described so far, an example of the movement of the magnets 7 of the three magnetron sputtering units is shown in FIG. The magnet 7a of the first magnetron sputtering unit 10a starts moving first and continues to move in a cycle of 9 seconds. The magnet 7b of the second magnetron sputtering unit 10b continues to move in the same period of 9 seconds after 5 seconds. Further, the magnet 7c of the third magnetron sputtering unit 10c continues to move in the same period of 9 seconds after the delay of 10 seconds. The magnets 7 of the respective magnetron sputtering units 10 are thus continuously moved at different times. The deviation of the magnets 7b, 7c from the start of movement time will be described later.

Next, a method of controlling the movement of the magnet 7 of the magnetron sputtering unit 10 will be described. First, the idea of uniformizing the film thickness in the conveyance direction on the substrate in the present embodiment will be described. Magnetron sputtering unit The magnet 7 of 10 is reciprocated before and after the center position of the cathode 6 in the conveyance direction. Further, the substrate 1 also moves in a reciprocating movement of the magnet 7, and the conveyance direction moves at a constant speed (fixed speed). Fig. 6 is a schematic view showing the relative speed and film thickness of the magnet 7 based on the substrate to be transported for any one of the magnetron sputtering units 10.

Fig. 6 is a schematic view for explaining the relationship between the film thickness on the substrate and the speed of the magnet 7, and in the upper part of Fig. 6, the relative velocity of the magnet 7 based on the substrate is shown as the magnet 7 to the substrate. The relative velocity V _ms indicates the film thickness at the position on the substrate corresponding to the horizontal axis of the upper segment in the lower portion of Fig. 6. The horizontal axis of Fig. 6 is the position on the substrate in the substrate transport direction. Further, in the actual sputtering film forming apparatus, the substrate is transported at a constant speed from the right side to the left side of the drawing on the sixth drawing. Here, for the sake of convenience, the substrate is viewed by fixing the substrate, so the magnet 7 is opposed to The substrate often moves while changing speed from left to right. The relative velocity V _{ms of} the magnet 7 to the substrate is plotted in the right direction in Fig. 6 to make a graph.

The range of A and B described in Fig. 6 indicates the range in which the magnet 7 moves in the reverse direction of the substrate conveyance direction, and the relative speed of the magnet 7 to the substrate is relatively fast. The range of C indicates a range in which the magnet 7 moves in the substrate conveyance direction (forward direction), and the relative speed of the magnet 7 to the substrate is a relatively slow region. Further, A', B', and C' indicate areas where the magnet stops. The sum of the ranges A+A'+B+B'+C+C' indicates the distance over which the substrate advances during the reciprocating movement of the magnet 7 for one cycle.

A relatively thin film is deposited on the substrate corresponding to A and B in FIG. 6 and stacked with respect to the range corresponding to C in FIG. Thicker film. Since the DC power supplied to the cathode is constant, the density of the sputtered atoms released from the target is constant, and the release position of the sputtered atoms is at a position corresponding to the position of the magnet 7. Therefore, the film thickness on the substrate is inversely proportional to the relative speed of the magnet 7 to the substrate.

However, the film thickness change on the substrate does not change abruptly as the relative speed of the magnet 7 to the substrate changes, and changes smoothly as shown in the lower portion of Fig. 6. The sputtered atoms released from the target are sputtered from the region around the width of the magnet 7, so that the distribution of the sputtered atoms released is smooth, and the distance between the target and the substrate is splashed by the sputtered atoms. The reason for the expansion of the degree.

What is important here is to adjust the moving speed of the magnet 7 to the cathode and the transport speed of the substrate so that the lengths of the substrates in the respective substrates A, B, and C are the same in the substrate transport direction on the substrate. Further, the distances in the substrate transport direction formed on the substrate in accordance with the respective ranges of A', B', and C' are also the same. By making the length of the film formation (the distance in the substrate conveyance direction) the same, the film thickness of the film formation by the second and third magnet sputtering units described later can be made uniform in the conveyance direction.

Fig. 7 shows the relative velocity V _ms of the magnet 7 to the substrate when the magnets 7 of the three magnet sputtering units are viewed from the substrate. The position on the substrate on the horizontal axis is represented by alignment of three graphs. The relative velocity V _ms of the magnet 7a of the first magnetron sputtering unit 10a is the same as that of Fig. 6. The magnet 7b of the second magnetron sputtering unit 10b is repeatedly moved in the same manner with respect to the magnet 7a of the first magnetron sputtering unit 10a at a position shifted by A+A' on the substrate. The movement of the magnet 7c of the third magnetron sputtering unit 10c with respect to the magnet 7a of the first magnetron sputtering unit 10a is also shifted by a distance of A+A'+B+B' on the substrate. . In other words, the magnet 7 is repeatedly moved for a specific period, and when the substrate is used as a reference, the magnet 7b is shifted by 1/3 cycle in any one direction with respect to the magnet 7a, and the magnet 7c is offset in the direction of the magnet 7a by 2/. 3 cycles (or 1/3 cycle in reverse offset).

As a result, the region (region A) on the substrate corresponding to the region A in FIG. 7 is formed in a state where the relative speed of the first magnetron sputtering unit 10a is relatively fast between the magnet 7a and the substrate. The film is formed in a state in which the second magnetron sputtering unit 10b is relatively slow in the relative speed of the magnet 7b and the substrate, and the relative speed of the third magnetron sputtering unit 10c is based on the magnet 7c and the substrate. It is formed into a film in a fast state. The areas of B and C in Fig. 7 are also the same, and two of the three magnetron sputtering units are formed in a state in which the relative speed of the magnet is relatively fast, in one line with the magnet. The film is formed in a state where the relative speed is relatively slow. When a film is formed at a relative speed of such a magnet, a relatively thin film is formed twice in each region, and a relatively thick film is formed at a time. Therefore, in each of the regions A, B, and C, the film thickness of the three magnetron sputtering units is the same.

In the above description, the relative speed of the magnet to the cathode during the constant velocity movement is described as a constant portion. However, in each of the regions A, B, and C, the acceleration region and the deceleration region of the magnet are present at both ends of each region. When this part is assumed to be three magnetron sputtering units, the two relatively fast speed regions and the relatively slow speed regions overlap on the same substrate. Therefore, it also includes the acceleration zone and the deceleration zone. The film thicknesses of the three magnetron sputtering units in the respective regions A, B, and C are the same.

Next, the regions A', B', and C' of the seventh drawing in which the magnet 7 is stopped in the state where the cathode is stopped will be described. When the thickness of the regions A', B', and C' is the thickness of the substrate (the relatively thick film thickness) formed when the magnet 7 in the regions A, B, and C moves in the substrate transport direction, and When the magnet 7 is moved in the reverse direction, the film thickness is formed between the thickness of the substrate (a relatively thin film thickness). Of course, the film thickness on the substrate formed in the regions A', B', and C' is the same. In the three magnetron sputtering units, the regions A', B', and C' are laminated on the substrate in the same film thickness. The control is performed by the movement of the magnet 7 obtained by the calculation formula described later. From this, it is understood that the thickness of the three layers is laminated by the regions A', B', and C', and the passage of the layers A, B, and C The film thickness of the three layers laminated in the region is the same.

The above is the idea of the film forming method of the embodiment and the control method of the film forming apparatus. That is, the lengths on the substrates formed in the regions of A, B, and C are the same. The lengths on the substrates formed in the regions of A', B', and C' are set to be the same. The movement (phase) of the magnets 7 of the three magnetron sputtering units is shifted by the length of the film formed on the substrate in the region of A+A' to advance the film formation position on the substrate.

More specifically, at the time of film formation, the first film is formed on the substrate during the first movement, the second film is formed on the substrate during the second movement, and the third film is moved. During the third film formed on the substrate, each of which is made by a different magnetron sputtering unit (target) Row. At this time, by aligning the substrate conveyance speed and the movement timing of the magnet 7, the first film formed from one target and the second film formed from the other target are superposed on the substrate, and the remaining film is left. The third film formed by the target. Then, it is controlled such that the portions stacked when the magnets 7 are stopped in each of the first, second, and third movements overlap on the substrate. By such a film formation method, a film having a uniform thickness is formed by the substrate after the front surface (lower side) of the three targets 4a, 4b, 4c of the film forming chamber 100.

Next, a method of controlling the magnet 7 of the magnetron sputtering unit 10 will be described. Figure 8 is a graphical representation of the speed of the magnet 7 of the magnetron sputtering unit versus the cathode 6. The horizontal axis is time, indicating one cycle. The vertical axis represents the velocity V _mc of the magnet 7 to the cathode 6, and the reverse speed is set to a positive value. The speed control of the magnet 7 is constituted by two trapezoidal driving of the reverse movement of the same shape and a trapezoidal driving of the forward movement, and stopping after each trapezoidal driving. The cycle of reciprocating movement is set to T, and the stroke (one-way) is set to L. The acceleration time of the magnet 7 is set to T _acc1 , and the deceleration time is set to T _acc2 . Here, the acceleration time of the three trapezoidal driving and the deceleration time of the three trapezoidal driving are each set to be equal. Further, the magnets 7 are stopped at three places, and the stop time T _sew is also set to be equal. These values are usually determined by the requirements of the composition or film formation of the magnetron sputtering device.

When this constant velocity of the expected value calculated based reverse movement of the moving velocity V _b, and its time T _b, the time constant of the forward movement of the moving direction (conveying direction of the substrate) times its velocity V _f and T _f. Further, the time constant of the reverse movement of the moving time T _b with respect to two trapezoidal drive, a trapezoidal drive in the set T _b / 2. Furthermore, the velocity V _f of the constant velocity movement in the forward movement takes a positive value. In the figure, it is represented by -V _f . The magnet 7 is initially stopped at the forward end (initial position). Since then, the acceleration is accelerated in the reverse _direction with an equal acceleration between times T _acc1 . Then, the reverse constant velocity movement is performed only at time T _b /2. The speed at this time is V _b . Thereafter, when the constant acceleration is decelerated only at time T _acc2 and the speed becomes 0, the period is continued during the time T _sew . The distance moved to the cathode 6 during this period becomes the area of the first (leftmost) trapezoid of Fig. 7. Further, as will be described later, the speed V _{f of the} magnet 7 to the forward direction of the cathode 6 is set to be lower than the substrate conveyance speed V _t .

Then, the movement is also driven in a trapezoidal direction in the reverse direction, and reaches the stroke end to the reverse side, and only T _sew continues to stop. Here, the magnet 7 moves the same distance with respect to the cathode 6. The distance moved by the two trapezoidal drives must be equal to the stroke L. Since the moving distance by a trapezoidal drive is L/2, it becomes

Here, T _acc is the average of the acceleration time T _acc1 and the deceleration time T _acc2 , and becomes

Then, the magnet 7 is accelerated by the constant acceleration during the period of time T _acc1 in the forward direction. Thereafter, the forward constant velocity movement is performed only at time _Tf . The speed at this time is V _f . Thereafter, when the constant acceleration is decelerated only at time T _acc2 and the speed becomes 0, the period is continued during the time T _sew . At this time, the magnet 7 is returned to the forward stroke end (initial position). The distance moved to the cathode 6 during the forward movement becomes the area of the (most right) trapezoid at the end of Fig. 7, and since it must be equal to the stroke L, it becomes [Equation 3] L = ( T _f + T _acc ) V _f . . . (2)

The time from which the stop time T _sew is subtracted from the period T is defined as T'.

[Formula 4] T '= T -3 T _sew

When the time in each movement between 1 cycle is added, it becomes [Equation 5] T _f + T _b +6 T _acc = T '. . . (3)

Next, the relative speed of the magnet to the substrate will be described based on Fig. 9. The horizontal axis of Fig. 9 is time, and the same as Fig. 8 shows one cycle of reciprocating movement. The vertical axis represents the relative velocity V _ms of the magnet to the substrate, and the reverse direction of the substrate conveyance direction is represented as a positive value. When the conveyance speed of the substrate is V _t , the relative velocity V _ms of the magnet to the substrate may be V _t plus V _{t mc} with respect to the cathode, and is expressed by the following formula.

[Equation 6] V _ms = V _mc + V _t

Therefore, when the graph of Fig. 8 is moved in parallel in the vertical axis direction only by V _t , it becomes a graph of the relative speed of the ninth graph. When the magnet 7 moves to the cathode 6 in the opposite direction at a constant speed, the relative velocity with respect to the substrate becomes V _t + V _b , and the relative velocity with respect to the substrate when moving in the forward direction is V _t - V _f ( V _f is positive). Further, when the magnet relative to the cathode is stopped Off 6 7 pairs relative speed of the substrate to become V _t.

By the trapezoidal driving of the first (left side) in Fig. 8, the distance that the magnet 7 moves toward the substrate becomes the area of the portion shown in a of Fig. 9 (the total area of the trapezoidal portion and the rectangular portion below it). The distance indicated by a is the same as the relative moving distance of A shown in Fig. 5. Similarly, with the second (central) trapezoidal drive in Figure 8 The distance that the magnet 7 moves toward the substrate becomes the area of the oblique line shown in b of FIG. The distance indicated by b is the same as the relative movement distance of B shown in Fig. 6. By the trapezoidal driving of the last (right side) in Fig. 8, the distance that the magnet 7 moves toward the substrate becomes the area of the oblique line shown by c in Fig. 8. The distance indicated by c is the same as the relative moving distance of C shown in Fig. 6. The areas of a, b, and c must be equal. Therefore, the following formula must be established. Further, since the area of the trapezoidal portion is equal to the stroke L, it is represented by L.

By solving the above equations (1) to (4), the velocity V _b of the constant velocity movement in the reverse movement of the magnet 7 and its time T _b , the velocity V _f of the constant velocity movement in the forward movement, and the time thereof T _{f is} as follows.

Since all the values are known, the reciprocating movement of the magnet 7 of the magnetron sputtering unit 10 can be controlled.

By way of example, the results calculated by (5) to (8) are shown in the following conditions. The calculation results when the substrate conveyance speed V _t =33.33 mm/s, the period T=9 seconds, the stroke L=100 mm, the acceleration time T _acc1 and the deceleration time T _acc2 are both 0.3 seconds and the stop time T _sew =0.4 seconds are as follows Like.

The speed of the constant velocity movement of the magnet 7 in the reverse direction is V _b = 62.5 mm/s, and the time T _b = 1.0 s, and the speed of the constant velocity movement of the magnet 7 in the forward direction V _f = 18.87 mm / s, The time T _f = 5.0 s, and the movement and speed of the magnet 7 at this time are shown in Figs. 2 and 3 .

In the present embodiment the type, order-based magnet 7 Cis rate of the cathode 6 to the substrate transport velocity is less than V _f V _t, i.e., the magnet 7 is not overtake the substrate is a prerequisite. The conditions of (5)~(8) must be all positive and can be clearly known. However, if T _b >0 of the formula (7) holds, all of the formulas (5) to (8) become positive. Therefore, in order to satisfy the condition that the speed V _{f is} smaller than the substrate conveyance speed V _t , the following formula is established with respect to the period T.

There is a lower limit in the period T, which must be set to a value greater than this. Increasing the period T is because the moving speed _Vf of the magnet 7 is slowed down, and the load of the driving mechanism of the magnet 7 is reduced, so that no problem occurs in the mechanism.

Next, the film thickness stacked on the substrate is used to be uniform at least in the conveyance direction. The range of A, B, and C on the substrate of Fig. 7 is the range in which the magnet 7 is formed while moving. In the three ranges composed of the regions A, B, and C, each of the two layers (thick film) and the (thin film) are laminated twice. Here, the (thin film)-based magnet 7 has a relative velocity with respect to the substrate at a portion where the cathode 6 is formed to move in the reverse direction (V _t + V _b ). Since the film thickness is inversely proportional to the relative speed, when the proportional constant is D, the film thickness of the (thin film) is expressed by the following formula.

Next, the (thick film) magnet 7 is a portion where the cathode 6 is formed to move in the forward direction, and the relative velocity with respect to the substrate is (V _t - V _f ) (however, V _f > 0). When the film thickness of (thick film) is the same proportional constant D, it is represented by the following formula.

In the range of A, B, and C (thick film), the thickness of the two layers (thick film) is doubled.

When substituting (5), (6) in the above formula, it becomes

The magnets 7 refers to the relative speed of the substrate is intended to be the thickness of the laminate is three times when V _t. That is, it is the same as the film thickness at the time when the magnets in the range of A', B', and C' in the third layer of Fig. 7 are stopped.

From this, it is understood that the ranges of A, B, and C in Fig. 7 and the film thicknesses in the range of A', B', and C' are equal, indicating that the film thickness stacked on the substrate is uniform at least in the conveyance direction. The above is the speed control method of the magnet of the magnetron sputtering unit. Although the magnets of the three magnetron sputtering units continue to move in the same speed control method, they each move with a time deviation. Hereinafter, the deviation of time will be described.

Fig. 10 shows an explanation of the starting time of the magnets 7a, 7b, 7c of the three magnetron sputtering units 10a, 10b, 10c. The starting time of the magnet 7a of the first magnetron sputtering unit 10a was set to 0 seconds. The second unit 10b of the magnetron-sputtering magnet 7b initiating time is set to T _w12, the third magnet unit 10c of the magnetron sputter plating 7c initiating time is set T _w13. These times are referred to as standby time, and these are found.

First, it is assumed that the cathode centers of the three magnetron sputtering units 10a, 10b, and 10c are disposed so as to overlap at the same position in the substrate conveyance direction, and the standby time is considered. As shown in Fig. 6, the magnet 7b of the second magnetron sputtering unit 10b corresponds to the substrate in a state where the magnet 7a of the first magnetron sputtering unit 10a and the substrate are separated by the A+A' distance. . This corresponds to the magnet starting only at a time one third of one cycle slower. When one cycle is set to 360°, 1/3 thereof becomes 120°, which is referred to as a phase difference θ ₁₂ . That is, the standby time T _w12 at this time becomes

Similarly, the phase difference θ ₁₃ of the magnet 7c of the third magnetron sputtering unit 10c is 240°. In general, when the phase difference of the magnet of the nth magnetron sputtering unit is θ _1n , the slave standby time T _w1n of the magnet of the nth magnetron sputtering unit becomes

In fact, since the cathode centers of the three magnetron sputtering units are not in the same position, it is then assumed that the cathode center positions are different. Fig. 11 shows the distance in the substrate transport direction between the cathode centers of the three magnetron sputtering units 10a, 10b, and 10c. The substrate is arranged to move in the right direction in the drawing at the conveyance speed V _t . From the first unit 10a of the magnetron sputtering cathode center and the second unit 10b of the magnetron sputtering cathode centers to X _12, the first unit 10a of magnetron cathode sputtering, and the third magnetic center The distance from the cathode center of the control sputtering unit 10c is set to X ₁₃ . In general, the distance between the cathode center of the first magnetron sputtering unit 10a and the cathode center of the nth magnetron sputtering unit is set to X _1n . Since the time required for the substrate to move at this distance is X _1n /V _t , the standby time T _w1n becomes the following formula

Further, since the magnet continues to move during the period T, the standby time does not change even if it is only the period T, and the positional relationship with respect to the substrate. Therefore, the standby time T _w1n of the nth magnetron sputtering unit is expressed by the following equation.

Here, m is an arbitrary integer. The integer m may be appropriately determined, but in the present embodiment, the first item and the second item on the right side will be used.

The remainder of the period T is used as the standby time T _w1n . In this way, the magnets of all the magnetron sputtering units can be moved in the shortest standby time, and the sputtering can be prepared early.

Next, the film thickness distribution on the substrate at the time of using the sputtering film formation method will be described. Fig. 12 shows the distribution of the transport direction of the film stacked on the substrate. The film thickness was determined by simulation using the erosion measurement of the target of the actual device. It is assumed that the substrate has a sufficient length in the conveying direction. The actual device and film formation conditions are as follows. The length of the magnet 7 in the transport direction is 200 mm, the length of the target 4 in the transport direction is 300 mm, and the distance between the target 4 and the substrate is 75 mm. The target 4 was aluminum (Al) and was formed into a film at a pressure of 0.1 Pa using argon (Ar) as a process gas.

Hereinafter, the calculation conditions (indicated in FIGS. 2 and 3) are calculated. The distance between the cathode center of the first magnetron sputtering unit 10a and the cathode center of the second magnetron sputtering unit 10b is set to X ₁₂ = 300 mm, and the first magnetron sputtering unit 10a is used. The distance between the cathode center and the cathode center of the cathode center of the third magnetron sputtering unit 10c is set to X ₁₃ = 600 mm. The substrate conveyance speed V _t =33.33 mm/s, the period T=9 seconds, the stroke L=100 mm, the acceleration time T _acc1 and the deceleration time T _{acc2 were both} 0.3 seconds and the stop time T _sew =0.4 seconds.

In Fig. 12, the film thickness on the substrate produced by each magnetron sputtering unit is indicated by three lines below the graph. The thicker regions of each film thickness are slightly longer than the thin regions. Each period on the substrate is V _t . T = 300mm. The lines are stacked on the substrate by 100 mm each to form a film. The upper thick line is the film thickness laminated by the magnetron sputtering apparatus, and the total thickness of the three films below is total. The film thickness of the laminate is slightly uniform. When the following calculation formula of the film thickness distribution is used, the film thickness distribution becomes ±0.02%. Further, the calculation formula of the film thickness distribution is as follows.

Film thickness distribution (±%) = (maximum-minimum value) / (maximum value + minimum value) × 100

Next, the film thickness distribution on the substrate at the time of using the sputtering film formation method under other conditions will be described with reference to FIG. In the condition of Fig. 11, only the period T is changed to 60 seconds. The film thickness on the substrate produced by each magnetron sputtering unit is indicated by three lines below the graph. The thinner regions of each film thickness are longer than the thick regions. Its ratio is close to 2:1. Each period on the substrate is V _t . T = 2000 mm. The lines were stacked on the substrate by 666.7 mm each to form a film. The upper thick line is the film thickness laminated by the three magnetron sputtering apparatuses, and the thickness of the three films below is totaled. The film thickness of the laminate is slightly uniform. When the calculation formula of the film thickness distribution is used, the film thickness distribution becomes ±0.00%.

In the above embodiment, although the sputtering apparatus of the three magnetron sputtering units is mainly described, the present invention can be applied even when four or more magnetron sputtering units are provided. For example, in the case where four magnetron sputtering units are provided, the period of the magnet 7 is divided into four and operates. In other words, the respective magnets 7 are driven to move the following first to fourth steps into one cycle. That is, driving each magnet to make a smooth journey The end of the movement moves to the first movement stopped at the first specific position after the reverse direction, and the second movement that is stopped after the movement from the stop position after the first movement to the second specific position after the reverse movement, and the movement from the second specific position to the reverse direction The movement after the stroke end is stopped (fourth movement), and the third movement is stopped after moving from the reverse stroke end to the stroke end of the substrate conveyance direction (forward).

Then, at the time of film formation, the first film formed on the substrate during the first movement, and the second film formed on the substrate during the second movement, and the film formed during the third movement are formed. During the movement (fourth movement) between the third film of the substrate and between the second and third movements, the fourth film is formed on the substrate, and each of the magnetron sputtering units is different ( The target is carried out. Further, by controlling the first film, the second film, the third film, and the fourth film to overlap each other on the substrate, the film thickness of the film formation layer on the substrate is made uniform. At this time, the length of the forward direction of the film formed at the time of the first to fourth movements is controlled by the control unit to be equal. Similarly, in the case of having five magnetron sputtering units, the period of the magnet 7 is divided into five and operates, and in the case of having six magnetron sputtering, the period of the magnet 7 is divided into six and operated. Just fine.

The present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the spirit and scope of the invention. Therefore, in order to inform the public of the scope of the invention, the following patent application scope is attached.

The present invention claims priority on the basis of Japanese Patent Application No. 2012-131132, filed on Jun. 8, 2012, the entire disclosure of which is incorporated herein.

1‧‧‧Substrate

2‧‧‧ chamber

3‧‧‧Transport roller

4a, 4b, 4c‧‧‧ targets

5a, 5b, 5c‧‧‧ target shielding

6a, 6b, 6c‧‧‧ cathode

7a, 7b, 7c‧‧‧ magnets

8a‧‧‧Cathode insulation

9a‧‧‧Cathode partition wall (target holder)

10a, 10b, 10c‧‧‧ magnetron sputtering unit

11a, 11b, 11c‧‧‧ Magnet Moving Department

21‧‧‧Substrate drive unit

25‧‧‧Control Department

Claims (14)

A sputtering apparatus comprising: a vacuum container; a substrate conveying unit configured to convey a substrate in the vacuum container; and at least three target holding portions arranged in a conveying direction of the substrate to be held for a target for sequentially forming a substrate to be transported by the substrate transporting portion; a magnet portion disposed on a back side of each of the target holding portions; and a magnet driving portion for driving The magnet unit and the control unit control the substrate transport unit and the magnet drive unit to perform the magnet unit at a specific cycle when the target holding unit holds the target and forms a film. a first movement that is reversed from the conveyance direction and stops at the first specific position from the stroke end of the conveyance direction, and the second movement is stopped from the first specific position toward the reverse movement after the first movement The second movement and the third movement that is stopped from the reverse stroke end toward the conveyance direction and stopped at the stroke end of the conveyance direction, and each of the first and second movements 3 moves, the substrate made of the magnet portion relative movement of the distance becomes equal to the conveyance direction. The sputtering apparatus according to claim 1, wherein the substrate is conveyed at a constant speed. The sputtering apparatus according to claim 1, wherein the control unit controls the arbitrary one of the magnet portions to be a period during which the first movement is performed by the first film stacked on the substrate by the target corresponding to the one of the magnet portions, and during the second movement by the other one of the magnet portions a second film stacked on the substrate corresponding to the other target portion of the other magnet portion, and the other one of the magnet portions corresponding to the other one of the other magnet portions during the third movement period The third film, which is stacked on the substrate, is superposed on the substrate. The sputtering apparatus according to the first aspect of the invention, wherein, in each of the first movement, the second movement, and the third movement, the magnets are stopped for the same time. The sputtering apparatus according to the third aspect of the invention, wherein the control unit controls the portions of the first film, the second film, and the third film that are stacked while the magnet portion is stopped. Overlapping on the above substrate. The sputtering apparatus according to claim 1, wherein the second specific position is the reverse stroke end. The sputtering apparatus according to the first aspect of the invention, wherein the movement speed of the magnet portion when the first movement or the second movement is controlled, and the movement speed of the magnet portion during the third movement different. A sputtering method for depositing a film using a sputtering method of a sputtering apparatus, the sputtering apparatus comprising: a vacuum container; and a substrate conveying unit for conveying the substrate in the vacuum container; At least three target holding portions arranged in the conveyance direction of the substrate to hold a target for sequentially forming the substrate conveyed by the substrate conveyance portion; the magnet portion is disposed a magnet driving portion for driving the magnet portion on a back side of each of the target holding portions, wherein the sputtering film forming method is configured to hold the target material in the target holding portion and form a film At the time of the processing, the first movement of the respective magnet portions from the stroke end in the conveyance direction toward the conveyance direction and the first movement at the first specific position is performed in a predetermined cycle, and the first movement is performed from the first movement a third movement in which the specific position is reversely moved to the second specific position, and a third movement that is moved from the reverse stroke end toward the conveyance direction and stops at the stroke end of the conveyance direction, and each of the 1. In the second and third movements, the distance at which the substrate moves relative to the magnet portion in the transport direction is equal. The sputtering film forming method according to claim 8, wherein the substrate is conveyed at a constant speed. The sputtering film forming method according to the eighth aspect of the invention, wherein the one of the magnet portions is stacked on the target corresponding to the one of the magnet portions during the first movement. The first film on the substrate and the other one of the magnet portions are the second shift During the period of the movement, the second film stacked on the substrate by the target corresponding to the other one of the magnet portions and the other one of the magnet portions are moved during the third movement by the other The third film stacked on the substrate corresponding to the target portion of one of the magnet portions is superposed on the substrate. The sputtering film forming method according to claim 8, wherein in the respective strokes of the first movement, the second movement, and the third movement, the time at which the magnet portions are stopped is equal. The sputtering film forming method according to the eleventh aspect of the invention, wherein the first film, the second film, and the third film are controlled to be stacked while the magnet portion is stopped. The above substrates overlap. The sputtering film forming method according to the eighth aspect of the invention, wherein the second specific position is the reverse stroke end. The sputtering film forming method according to the eighth aspect of the invention, wherein the moving speed of the magnet portion when the first movement or the second movement is controlled, and the magnet portion during the third movement The movement speed is different.