TW201619439A - A method of operating an electroless plating apparatus - Google Patents

Abstract

The present invention provides a method for operating an electroless plating apparatus, in which when any one of a plurality of process tanks, which contain plating tanks, breaks down, the number of defective substrate is reduced. The method enables the electroless plating apparatus to memorize a predetermined processing priority in accordance with the stability of a susbstrate being processed W to purified water. When any one of the plurality of process tanks breaks down, the purified water is supplied in a holder-retaining device 14 to determine whether, a redress procedure for the substrate W with a higher processing priority is executed. When the redress procedure is executable and after the procedure is executed, a substrate holder 42 which holds the substrate W is immersed in the purified water of the holder-retaining device 14; otherwise, when the redress procedure is non-executable and no redress procedure is executed, the substrate holder 42 which holds the substrate W is directly immersed in the purified water of the holder-retaining device 14.

Description

Operation method of electroless plating device

The present invention relates to an operation method of an electroless plating apparatus for plating a surface of a substrate such as a wafer.

A substrate processing apparatus for processing a substrate such as a wafer is known to have an electrolytic plating apparatus. The technique of forming a metal film on a substrate by chemically reducing metal ions in the plating solution without flowing an electric current in the electroless plating system.

The ninth diagram shows a diagram of an electroless plating apparatus. As shown in the ninth figure, the electroless plating apparatus includes: a device frame 110; a loading cassette 112 for mounting a wafer cassette containing a substrate W such as a wafer; and an operation control unit 113 for controlling the operation of the electroless plating apparatus; And an aligner 114 that aligns the orientation plane or groove position of the substrate W with a specified direction. The electroless plating apparatus further includes a spin-washing dryer (SRD) 116 that spins the substrate W after the plating treatment at a high speed, and a holder storage chamber 118 that stores a plurality of substrate holders 117 in a vertical posture; The substrate W to be plated is mounted on the substrate holder 117, the substrate loader 120 that takes out the plated substrate W from the substrate holder 117, and the substrate transfer robot 122 that transports the substrate W.

A traveling mechanism 115 is disposed along the direction in which the loading cassettes 112 are arranged, and the traveling mechanism 115 is provided with the substrate conveying robot 122. An aligner 114 is disposed adjacent to the traveling mechanism 115. The substrate transport robot 122 is accessed by being mounted on the travel mechanism 115 and is mounted on the loading cassette. The wafer cassette of 112 is configured by taking out the substrate W to be plated from the wafer cassette and feeding the substrate W to the substrate loader 120.

The device frame 110 is provided with: a cleaning unit 126 before cleaning the surface of the substrate W (for example, removing copper oxide on the surface of the substrate W); and a core forming unit for activating the surface of the substrate W (for example, forming a palladium core on the surface of the substrate W) 128. The front cleaning unit 126 includes a pre-cleaning tank 126a for storing the cleaning liquid before cleaning the surface of the substrate W, and a substrate W immersed in the pre-washing liquid with a cleaning liquid (for example, pure water). A rinse tank 126b. The core forming unit 128 includes a core forming groove 128a for forming a palladium core on the surface of the substrate W, and a second flushing groove 128b for washing the substrate W on which the palladium core is formed by a cleaning liquid (for example, pure water).

The electroless plating apparatus further includes: a first plating unit 130 that forms a first metal film made of, for example, a cobalt film (Co) on the surface of the substrate W by electroless plating; and by electroless plating A second plating unit 132 of, for example, a second metal film made of a gold film (Au) is formed on the first metal film. The first plating unit 130 includes a first plating tank 130a for storing a plating solution such as a cobalt plating solution, and a plating solution immersed in the first plating tank 130a with a cleaning liquid (for example, pure water). The third rinse tank 130b of the liquid substrate W.

The second plating unit 132 includes a second plating tank 132a that stores a plating solution such as a gold plating solution, and a plating solution that is immersed in the second plating tank 132a by a cleaning liquid (for example, pure water). The fourth rinse tank 132b of the liquid substrate W.

An example of a step of plating the substrate W using the electroless plating apparatus described above will be described with reference to the tenth (a)th to tenth (c)th drawings. 10(a) to 10(c) are schematic views showing a cross section of the substrate W, and the example shown in the tenth (a) is a photoresist layer 149 formed on the base metal film 148, and is in the light. A copper film 150 is formed in the opening of the resist layer 149. First, the substrate W is immersed in the front cleaning tank. In the pre-cleaning liquid in 126a, copper oxide formed on the surface of the copper film 150 on the substrate W is removed, and then the substrate W is rinsed in the first rinse tank 126b.

Next, in the core forming groove 128a, a palladium (Pd) core is formed on the copper film 150, and then the substrate W is washed in the second rinse tank 128b. Next, in the first plating tank 130a, the substrate W is immersed in a cobalt (Co) plating solution, and a cobalt film 151 is formed on the surface of the copper film 150 (see FIG. 10(b)). Then, the substrate W is rinsed with the third rinse tank 130b. Then, the substrate W is immersed in the gold (Au) plating solution in the second plating tank 132a, and the gold film 152 is formed on the cobalt film 151 (refer to the tenth (c)). Then, the substrate W is rinsed with the fourth rinse tank 132b.

When any one of the cleaning tank 126a, the core forming tank 128a, the first plating tank 130a, and the second plating tank 132a is broken, it is necessary to stop the processing of the substrate W and further relieve the substrate W. In the remedy method of the substrate W, it is considered that the substrate W subjected to any one of the front cleaning tank 126a, the core forming groove 128a, the first plating tank 130a, and the second plating tank 132a is immersed in the rinsing tanks 126b and 128b. In any of the cleaning solutions (pure water) of any of 130b and 132b.

However, since the stability of the substrate W to the pure water depends on the material constituting the exposed surface of the substrate W, and the substrate W in a state in which the stability is low is immersed in the pure water in the rinse tank, the substrate W becomes a defective product. For example, when a palladium core is formed on the surface of the copper film 150, the exposed surface of the copper film 150 is made of copper (Cu) and palladium. When such a substrate W is immersed in pure water, copper having a small ionization energy is dissolved in pure water, and it is extremely difficult to dispose of the substrate W.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 61-91931

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2011-146448

The present invention has been made in view of the above problems, and an object thereof is to provide an operation method for an electroless plating apparatus capable of reducing the number of substrates to be defective when any one of a plurality of processing tanks including a plating tank is defective.

In order to achieve the above object, a method for operating an electroless plating apparatus according to the present invention includes: a substrate holder that holds a substrate; and a plurality of processing tanks for performing electroless plating a plurality of processes for plating; and a holder storage tray for storing the substrate holder when the substrate is not held, wherein the electroless plating device is stored in accordance with the stability of the substrate to be treated for pure water. In the processing priority order, when any one of the plurality of processing tanks fails, pure water is supplied to the holder storage tank, and a relief process for performing a higher priority processing on the substrate is performed, and the relief can be performed. In the case of the step, after the remedy step is performed, the substrate holder holding the substrate is immersed in the pure water in the holder storage tank, and the remedy step cannot be performed without performing the remedy step. The substrate holder of the substrate is immersed in pure water in the holder storage tank.

A suitable aspect of the present invention is characterized in that the pure water is a deaerated water having a low dissolved oxygen concentration.

A feature of the present invention is that the relief process is an electroless plating process in which a metal film thicker than a predetermined target thickness is formed on the surface of the substrate.

A feature of the present invention is that the metal film is a cobalt film.

A suitable aspect of the present invention is characterized in that the plurality of processes include: pre-substrate cleaning, activation of the substrate, and electroless plating of the substrate.

According to the present invention, the substrate is immersed in the pure water in the holder storage tank while the stability of the pure water is as high as possible. As a result, the number of substrates that become defective can be reduced.

1, 110‧‧‧ device framework

2, 112‧‧‧ loading 埠

3. 113‧‧‧Action Control Department

4, 114‧‧ ‧ aligner

5, 115‧‧‧ Driving agencies

6, 116‧‧‧Spin Flush Dryer (SRD)

10, 120‧‧‧ substrate loader

12, 122‧‧‧ substrate transfer robot

14, 118‧‧‧ retainer storage slot

16, 126‧‧‧ front cleaning unit

16a, 126a‧‧‧ before cleaning tank

16b, 126b‧‧‧ first rinse tank

18, 128‧‧‧nuclear forming unit

18a, 128a‧‧‧nuclear forming trough

18b, 128b‧‧‧second flushing tank

20, 130‧‧‧ first plating unit

20a, 130a‧‧‧ first plating tank

20b, 130b‧‧‧ third flushing tank

24, 132‧‧‧Second plating unit

24a, 132a‧‧‧second plating tank

24b, 132b‧‧‧ fourth flushing tank

26‧‧‧Workbench

28‧‧‧Sheet Holder Upset Mechanism

30‧‧‧Conveyor

32‧‧‧ Arms

34‧‧‧claw

35‧‧‧Pure water supply and discharge mechanism

36‧‧ ‧ compartment

37‧‧‧ partition wall

40‧‧‧Fixed base

42, 117‧‧‧ substrate holder

44‧‧‧ Keep arm

44a‧‧‧First gap

44b‧‧‧Second gap

44c‧‧‧ third gap

45‧‧‧Support arm

46‧‧‧Protruding

59, 60, 61, 62, 63‧‧‧ two-way lifts

65, 66‧‧‧1 direction lift

70, 71‧‧‧ substrate holder transport mechanism

75‧‧‧Supply pipeline

76‧‧‧ON-OFF valve

77‧‧‧Drainage line

80‧‧‧Cobalt oxide film removal device

81‧‧‧ etching device

82‧‧‧ Film Thickness Tester

148‧‧‧Base metal film

149‧‧‧Light resist

150‧‧‧ copper film

151‧‧‧Cobalt film

152‧‧‧ gold film

W‧‧‧Substrate

The first figure is a plan view showing an embodiment of an electroless plating apparatus.

The second figure shows a diagram of the substrate holder.

The third figure shows a diagram of a substrate sandwiched between the gaps of the holding arms.

The fourth figure shows a schematic diagram of a pure water supply and discharge mechanism.

The fifth figure is a plan view of the holder storage tank.

The sixth diagram shows a map of processing priorities.

The seventh (a) to seventh (d) drawings show the substrate relief process diagram when the second plating tank fails.

The eighth (a) to eighth (d) drawings show the substrate relief process diagram when the core forming groove fails.

The ninth diagram shows a diagram of an electroless plating apparatus.

Tenth (a) to tenth (c) are schematic views showing a cross section of the substrate.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the first to eighth embodiments, the same or equivalent components are denoted by the same reference numerals, and the description thereof will be omitted.

The first figure is a plan view showing an embodiment of an electroless plating apparatus. The electroless plating apparatus is a substrate processing apparatus that performs various processes on a substrate. As shown in the first picture The electroless plating apparatus includes: a device frame 1; a loading cassette 2 on which a wafer cassette containing a substrate W such as a wafer is mounted; an operation control unit 3 that controls the operation of the electroless plating apparatus; and a substrate W The orientation plane or groove position is aligned with the aligner 4 in the specified direction. The electroless plating apparatus further includes a spin-washing dryer (SRD) 6 that spins the substrate W after the plating process at a high speed, and stores the holder storage tanks 14 of the plurality of substrate holders 42 in a vertical posture; The plated substrate W is mounted on the substrate holder 42 and the substrate loader 10 of the plated substrate W is taken out from the substrate holder 42 and the substrate transfer robot 12 that transports the substrate W. The holder storage tank 14 is configured to accommodate, for example, 37 substrate holders 42.

A traveling mechanism 5 is disposed along the direction in which the loading cassettes 2 are arranged, and the traveling mechanism 5 is provided with the substrate transfer robot 12. An aligner 4 is disposed adjacent to the traveling mechanism 5 . The substrate transfer robot 12 accesses the wafer cassette mounted on the loading cassette 2 by moving on the traveling mechanism 5, takes out the substrate W to be plated from the wafer cassette, and sends the substrate W to the substrate loading. The structure of the machine 10 is constructed.

The apparatus frame 1 is provided with a front cleaning unit 16 for cleaning the surface of the substrate W (for example, copper oxide for removing the surface of the substrate W); and a core forming unit 18 for performing activation treatment (for example, forming a palladium core) on the surface of the substrate W. . The front cleaning unit 16 includes a front cleaning tank 16a for storing the cleaning liquid before cleaning the surface of the substrate W, and a substrate W immersed in the front cleaning liquid with a cleaning liquid (for example, pure water). A rinse tank 16b. The front cleaning tank 16a is configured to accommodate one substrate holder 42, and the first rinse tank 16b is also configured to accommodate one substrate holder 42. The core forming unit 18 includes a core forming groove 18a for forming a palladium core on the surface of the substrate W, and a second flushing groove 18b for washing the substrate W on which the palladium core is formed by a cleaning liquid (for example, pure water). The core forming groove 18a is configured to accommodate one substrate holder 42, and the second processing groove 18b is also for accommodating one substrate holder 42. The way it is structured.

The electroless plating apparatus further includes: a first plating unit 20 that forms a first metal film made of, for example, a cobalt film (Co) on the surface of the substrate W by electroless plating; and the first plating by electroless plating A second plating unit 24 of, for example, a second metal film made of a gold film (Au) is formed on the metal film. The first plating unit 20 includes a first plating tank 20a for storing a plating solution such as a cobalt plating solution, and a plating liquid immersed in the first plating tank 20a with a cleaning liquid (for example, pure water). The third flushing tank 20b of the substrate W in the middle. The first plating tank 20a is configured to accommodate the two substrate holders 42, and the third rinse tank 20b is configured to accommodate one substrate holder 42.

The second plating unit 24 includes a second plating tank 24a for storing a plating solution such as a gold plating solution, and a plating liquid immersed in the second plating tank 24a with a cleaning liquid (for example, pure water). The fourth rinse tank 24b of the substrate W in the middle. The second plating tank 24a is configured to accommodate ten substrate holders 42, and the fourth rinse tank 24b is configured to accommodate one substrate holder 42. The front cleaning unit 16, the core forming unit 18, the first plating unit 20, the second plating unit 24, and the holder storage tank 14 are arranged in a straight line in this order. Hereinafter, the front washing tank 16a, the core forming tank 18a, the first plating tank 20a, and the second plating tank 24a may be referred to as processing tanks, respectively.

Each of the first plating unit 20 and the second plating unit 24 includes an overflow tank (not shown). The plating liquid overflowing on the side wall of the first plating tank 20a flows into the overflow tank, and returns to the first plating tank 20a through a circulation line (not shown). Similarly, the plating liquid overflowing on the side wall of the second plating tank 24a flows into the overflow tank, and is returned to the second plating tank 24a through a circulation line (not shown). A temperature adjustment portion of the filter or the plating solution is separately disposed in the circulation lines.

The substrate loader 10 is disposed adjacent to the holder storage groove 14. The substrate loader 10 includes: a table 26 on which the substrate holder 42 is horizontally placed; and a base for the substrate holder 42 to be inverted The plate holder upturns the mechanism 28. The substrate holder up-down mechanism 28 is provided on the outer side of the table 26. The substrate holder up-and-down mechanism 28 is configured to convert the substrate holder 42 from a vertical posture to a horizontal posture and to place the substrate holder 42 on the table 26. The substrate W is mounted on the substrate holder 42 on the stage 26, and the substrate W is removed from the substrate holder 42.

The electroless plating apparatus includes a conveyor 30 that conveys the substrate holder 42 holding the substrate W in the horizontal direction. The conveyor 30 includes a fixed base 40 extending from the substrate loader 10 to the front cleaning unit 16 in the horizontal direction, an arm 32 movably movable in the horizontal direction on the fixed base 40, and mounted on the arm 32. The jaws 34. A drive source for moving the arm 32 in the horizontal direction may be a linear motor or a rack gear or the like. The jaws 34 are configured to hold the substrate holder 42.

The substrate holder 42 will be described with reference to the second figure. The second figure shows a diagram of the substrate holder 42. As shown in the second figure, the substrate holder 42 has projections 46, 46 that protrude from the outside. The support arm 45 extends between the projections 46,46. Two holding arms 44 and 44 that hold the substrate W are fixed to the support arm 45. The conveyor 30 conveys the substrate holder 42 in a state where the gripper 34 holds the support arm 45.

Each of the holding arms 44 has a first slit 44a, a second slit 44b, and a third slit 44c. The third figure shows a diagram of the substrate W sandwiched by the slits 44a to 44c of the holding arm 44. The third figure shows one holding arm 44. As shown in the third figure, the substrate W is held by the substrate holder 42 by inserting the peripheral edge portion of the substrate W into the slits 44a to 44c. As shown in the second figure, the substrate W is sandwiched by the slits 44a to 44c of the two holding arms 44 and 44 by sliding the substrate W from the position indicated by the broken line to the position indicated by the solid line. The substrate W is mounted on the substrate holder 42 by the substrate transfer robot 12 shown in the first drawing or the substrate sliding mechanism (not shown) mounted on the table 26.

Next, the operation of the electroless plating apparatus will be described with reference to the first drawing. First, by The two-way elevator 59 disposed adjacent to the holder storage tank 14 takes out the substrate holder 42 in the vertical posture from the holder storage groove 14. The two-way lifter 59 is configured such that the substrate holder 42 is raised and lowered, and the substrate holder 42 is further moved in the horizontal direction. The two-way elevator 59 can take out any of the substrate holders 42 from a plurality of substrate holders 42 that are aligned in the holder storage slot 14. The two-way elevator 59 feeds the substrate holder 42 to the conveyor 30, and the conveyor 30 delivers the substrate holder 42 to the substrate holder up-down mechanism 28 of the substrate loader 10. The substrate holder up-and-down mechanism 28 converts the substrate holder 42 from the vertical posture to the horizontal posture and places it on the table 26.

The substrate transfer robot 12 takes out one substrate W from the wafer cassette mounted on the cassette 2 and places it on the aligner 4. The aligner 4 aligns the orientation of the orientation plane or groove to a specified direction. The substrate transfer robot 12 takes out the substrate W from the aligner 4 and inserts the substrate W into the substrate holder 42 placed on the stage 26. More specifically, the substrate transfer robot 12 horizontally moves the substrate W to a predetermined position such that the substrate W is sandwiched by the slits 44a to 44c of the holding arm 44, by the position of the substrate W from the broken line of the second figure. The substrate W is loaded into the substrate holder 42 by sliding to the position indicated by the solid line.

Next, the substrate holder up-down mechanism 28 converts the substrate holder 42 from a horizontal attitude to a vertical posture. The jaws 34 of the arms 32 hold the substrate holder 42 in the upright state, and the conveyor 30 moves the substrate holder 42 to a designated position above the front cleaning tank 16a. A two-way elevator 60 is provided adjacent to the front washing tank 16a. The two-way elevator 60 is configured such that the substrate holder 42 is raised and lowered to further move the substrate holder 42 in the horizontal direction.

The two-way elevator 60 receives the substrate holder 42 from the conveyor 30, lowers the substrate holder 42, and immerses the substrate W held by the substrate holder 42 in the front washing tank 16a. In the clean liquid. The surface of the substrate W is washed by the pre-washing liquid. This pre-cleaning is, for example, a process of removing copper oxide on the surface of the substrate W, and is referred to as a pre-cleaning treatment. After the substrate W is washed front, the two-way lifter 60 raises the substrate holder 42 and picks up the substrate W from the front cleaning liquid.

The two-way elevator 60 moves the substrate holder 42 horizontally to the first rinsing tank 16b adjacent to the front cleaning tank 16a, lowers the substrate holder 42 and immerses the substrate W in the first rinsing tank 16b. In (pure water), the substrate W is washed (rinsed). After the substrate W is washed, the two-way lifter 60 raises the substrate holder 42 and picks up the substrate W from the cleaning liquid in the first rinse tank 16b.

The conveyor 30 receives the substrate holder 42 from the two-way elevator 60 to move the substrate holder 42 to a designated position above the core forming groove 18a. A two-way elevator 61 is provided adjacent to the core forming groove 18a. The two-direction elevator 61 is configured such that the substrate holder 42 is raised and lowered, and the substrate holder 42 is further moved in the horizontal direction.

The two-direction elevator 61 receives the substrate holder 42 from the conveyor 30, lowers the substrate holder 42, and arranges the substrate W held by the substrate holder 42 in the core forming groove 18a. The core forming groove 18a imparts a core (for example, a palladium core) for depositing a metal film to the surface of the substrate W. This treatment is called activation treatment (or catalyst application treatment). After the activation treatment, the two-way lifter 61 raises the substrate holder 42 and picks up the substrate W from the core forming groove 18a. Next, the two-direction elevator 61 moves the substrate holder 42 horizontally to the second rinse tank 18b adjacent to the core forming groove 18a, lowers the substrate holder 42 and immerses the substrate W in the second rinse tank 18b. In the clean liquid (pure water). The substrate W is washed (rinsed) with a cleaning solution. After the substrate W is washed, the two-way lifter 61 raises the substrate holder 42 and picks up the substrate W from the cleaning liquid in the second rinse tank 18b.

The conveyor 30 receives the substrate holder 42 from the two-way elevator 61 to hold the substrate The device 42 is moved to a specified position above the first plating tank 20a. A substrate holder transport mechanism 70 is provided adjacent to the first plating tank 20a. The substrate holder transport mechanism 70 is configured to horizontally transport the substrate holder 42 in a state where the substrate W is immersed in the plating liquid in the first plating tank 20a. A directional lifter 65 is provided on the outer side of the substrate holder transport mechanism 70. The one-way elevator 65 is configured to raise and lower the substrate holder 42.

The one-direction elevator 65 receives the substrate holder 42 from the conveyor 30, lowers the substrate holder 42, and delivers the substrate holder 42 to the substrate holder transport mechanism 70. The substrate holder transport mechanism 70 sends the substrate holder 42 from the holder input position IN to the holder take-out position OUT while the entire substrate W is immersed in the plating liquid in the first plating tank 20a. The substrate W moves in the plating solution, and at this time, the surface of the substrate W is electrolessly plated. The electroless plating is, for example, cobalt (Co) plating (cobalt plating treatment).

A two-way elevator 62 is provided outside the substrate holder transport mechanism 70. The two-way elevator 62 raises the substrate holder 42 that has reached the holder take-out position OUT, and picks up the substrate W from the plating liquid. Next, the two-way elevator 62 moves the substrate holder 42 horizontally to the third rinse tank 20b adjacent to the first plating tank 20a, lowers the substrate holder 42 and immerses the substrate W in the third rinse tank 20b. In the clean liquid (pure water). The substrate W is washed (rinsed) with a cleaning solution. After the substrate W is washed, the two-way elevator 62 raises the substrate holder 42 and picks up the substrate W from the cleaning liquid in the third rinse tank 20b.

The conveyor 30 receives the substrate holder 42 from the two-way elevator 62 to move the substrate holder 42 horizontally to a predetermined position above the second plating groove 24a. A substrate holder transport mechanism 71 is provided adjacent to the second plating tank 24a, and a direction lifter 66 is provided on the outer side of the substrate holder transport mechanism 71.

The one-direction elevator 66 receives the substrate holder 42 from the conveyor 30, lowers the substrate holder 42, and delivers the substrate holder 42 to the substrate holder transport mechanism 71. The substrate holder transport mechanism 71 transports the substrate holder 42 to the holder take-out position OUT from the holder insertion position IN in a state where the entire substrate W is immersed in the plating liquid in the second plating tank 24a. The substrate W moves in the plating solution, and at this time, the surface of the substrate W is electrolessly plated. The electroless plating is, for example, gold (Au) plating (gold plating treatment). In this manner, the substrate W is continuously subjected to two kinds of plating processes by the first plating unit 20 and the second plating unit 24, and different types of metal films are continuously formed on the surface of the substrate W. In the present embodiment, since the gold plating treatment is performed after the cobalt plating treatment, a gold film is formed on the cobalt film.

A two-way elevator 63 is provided on the outer side of the substrate holder transport mechanism 71. The two-direction elevator 63 raises the substrate holder 42 that has reached the holder take-out position OUT, and picks up the substrate W from the plating liquid. Next, the two-way lifter 63 moves the substrate holder 42 horizontally to the fourth rinse tank 24b adjacent to the second plating tank 24a, lowers the substrate holder 42 and immerses the substrate W in the fourth rinse tank 24b. In the clean liquid (pure water). The substrate W is washed (rinsed) with a cleaning solution. After the substrate W is washed, the two-way lifter 63 raises the substrate holder 42 and picks up the substrate W from the cleaning liquid in the fourth rinse tank 24b. The conveyor 30, the two-way lifts 59, 60, 61, 62, 63, the one-way lifters 65, 66, and the substrate holder transport mechanisms 70, 71 are collectively referred to as a transport device.

The conveyor 30 receives the substrate holder 42 from the two-way elevator 63, moves the substrate holder 42 in the horizontal direction, and delivers the substrate holder up-down mechanism 28. The substrate holder up-down mechanism 28 horizontally places the substrate holder 42 on the table 26. The substrate transfer robot 12 takes out the substrate W from the substrate holder 42 by sliding the substrate W from the position indicated by the solid line in the second figure to the position indicated by the broken line.

Then, the substrate transfer robot 12 transports the substrate W to the spin rinse dryer 6. The spin rinse dryer 6 rotates the substrate W at a high speed to dry the substrate W. The substrate transfer robot 12 takes out the dried substrate W from the spin rinse dryer 6 and returns it to the wafer cassette on which the cassette 2 is loaded. Thereby, the processing of the substrate W is completed.

In the operation of the electroless plating apparatus, when any one of the treatment tanks 16a, 18a, 20a, and 24a fails, pure water is supplied into the holder storage tank 14. Specifically, the electroless plating apparatus includes a pure water supply and discharge mechanism 35 that supplies pure water in the holder storage tank 14 and discharges pure water from the holder storage tank 14 . The operation control unit 3 is configured to control the operation of the pure water supply and discharge mechanism 35.

The pure water supply and discharge mechanism 35 will be described with reference to the fourth diagram. The fourth figure shows a schematic view of the pure water supply and discharge mechanism 35. As shown in the fourth figure, the pure water supply and discharge mechanism 35 includes a supply line 75 connected to the bottom of the holder storage tank 14, an ON-OFF valve 76 connected to the supply line 75, and a bottom connected to the holder storage tank 14. Discharge line 77. The supply line 75 is connected to a pure water supply line (not shown). When the ON-OFF valve 76 is opened, the pure water is supplied into the holder storage tank 14 through the supply line 75, and is discharged from the holder storage tank 14 through the discharge line 77.

The fifth drawing is a plan view of the holder storage tank 14. The holder storage tank 14 is configured to accommodate all of the substrate holders 42 present in the electroless plating apparatus, and has the number of treatments with the substrate W (pre-cleaning treatment, activation treatment, cobalt plating in the present embodiment) Four partitions 36 of equal treatment and four gold plating treatments. The compartments 36 are completely separated by the partition walls 37, and the pure water does not move between the compartments 36. The number of substrate holders 42 that can be accommodated in each of the compartments 36 corresponds to the maximum number of substrate holders 42 that can be accommodated in each of the processing tanks 16a, 18a, 20a, 24a. The pure water supply and discharge mechanism 35 is configured to supply pure water in each of the compartments 36. When a specified amount of pure water is retained in each of the compartments 36, the supply of pure water is stopped. The pure water supplied to the holder storage tank 14 is preferably a deaerated water having a low oxygen concentration.

When any one of the processing tanks 16a, 18a, 20a, and 24a fails, the substrate W is transferred to the holder storage tank 14 by the transfer device and the substrate holder 42, and immersed in the pure water in the holder storage tank 14. However, as described above, the stability of the substrate W to the pure water changes depending on the material constituting the exposed surface of the substrate W. Therefore, when the substrate W having a low stability is immersed in pure water, the substrate W becomes a defective product. The stability of the substrate W to pure water will be described below.

When a palladium core is formed on the surface of the copper film (refer to symbols 150 of the tenth (a)th to tenth (c)), the exposed surface of the substrate W is made of copper (Cu) and palladium. When such a substrate W is immersed in pure water, copper having a small ionization energy is dissolved in pure water, and it is extremely difficult to dispose of the substrate W. Therefore, it can be said that the substrate W on which the copper film and the palladium core are formed has very low stability against pure water.

When the cobalt-plated substrate W is immersed in pure water, the surface of the cobalt film is oxidized, and a cobalt oxide film is formed on the surface of the cobalt film. If the cobalt oxide film is not removed, the processing of the substrate W cannot be resumed after the electroless plating apparatus returns to the normal operation state. Therefore, it can be said that the substrate W after cobalt plating has low stability to pure water.

When the substrate W after the pre-cleaning is immersed in pure water, copper oxide is formed on the surface of the substrate W. However, by immersing the substrate W in the pre-cleaning liquid again, the copper oxide on the surface of the substrate W can be removed. Therefore, it can be said that the substrate W after the front cleaning has high stability against pure water. Even if the gold-plated substrate W is immersed in pure water, since the substrate W is not adversely affected, the possibility of relieving the substrate W is high. Therefore, it can be said that the substrate W after gold plating has a very high stability against pure water.

The operation control unit 3 preliminarily stores (stores) the priority order of the processing defined by the stability of the substrate W after the processing. The processing priority of this embodiment is the highest priority. Plating treatment, the treatment system with the second highest priority is pre-cleaned, the treatment with the second highest priority is cobalt plating treatment, and the treatment with the lowest priority is activation treatment ((1) gold plating treatment, (2) pre-washing Net treatment, (3) cobalt plating treatment, (4) activation treatment).

Referring to the sixth and seventh (a) to seventh (d) drawings, the relief method of the substrate W when the second plating tank 24a fails. The sixth diagram shows a map of processing priorities. The seventh (a) to seventh (d) drawings show the relief process of the substrate W when the second plating tank 24a fails.

When the second plating tank 24a fails, first, the loading of the substrate holder 42 by the unprocessed substrate W in the substrate loader 10 is stopped. Next, the pure water supply and discharge mechanism 35 supplies pure water into the holder storage tank 14. Then, the operation control unit 3 determines whether or not the execution of the substrate W can be performed in accordance with the priority order of memory ((1) gold plating treatment, (2) pre-cleaning treatment, (3) cobalt plating treatment, (4) activation treatment). A relief process with a higher priority. When the operation control unit 3 determines that the relief process can be performed, the substrate W is subjected to a relief process, and then the substrate W is immersed in the pure water in the holder storage tank 14.

As shown in the seventh (a), when the second plating tank 24a fails in the gold plating process of the substrate W, the gold plating treatment cannot be performed on the substrate W in the second plating tank 24a. However, in this case, when the substrate W is immersed in the plating solution in advance, the gold plating film is excessively formed on the substrate W, and as a result, the substrate W must be discarded. Therefore, in order to dispose of the substrate W, the substrate W in the second plating tank 24a is transferred to the partition chamber 36 by the conveyor 30, and the substrate W is immersed in the pure water in the compartment 36. As shown by the dotted arrow in the seventh diagram (a), the substrate W may be immersed in the cleaning liquid (pure water) in the fourth rinse tank 24b, and then the substrate W may be transferred to the partition chamber 36.

As shown in the seventh (b), when the second plating tank 24a fails in the cobalt plating treatment of the substrate W, the substrate W after the cobalt plating cannot be transferred to the second plating tank 24a. So first, will The substrate W in the first plating tank 20a is transferred to the third rinse tank 20b, and the substrate W is immersed in the washing liquid (pure water) in the third rinse tank 20b. Then, the substrate W is transferred to the compartment 36 together with the substrate holder 42 by the conveyor 30, and immersed in the pure water in the compartment 36. The substrate W after cobalt plating is housed in a compartment 36 different from the compartment 36 in which the substrate W after gold plating is accommodated. Since the respective compartments 36 are completely separated, the gold plating solution and the cobalt plating solution adhering to the substrate W and the substrate holder 42 are not mixed with each other.

As shown in the seventh (c), when the second plating tank 24a is broken in the activation process of the substrate W, the substrate W after the core forming groove 18a is transferred to the second rinsing tank 18b, and the second rinsing tank is used. Wash the washing solution in 18b. Then, the substrate W is transferred to the first plating tank 20a by the conveyor 30 together with the substrate holder 42 to perform cobalt plating. The cobalt plating treatment is preferred over the activation treatment in accordance with the priority order stored in the operation control unit 3. Therefore, after the activation treatment of the substrate W is completed, the substrate W is subjected to cobalt plating treatment. The stability of the substrate W after cobalt plating to pure water is higher than that of the substrate W subjected to the activation treatment to pure water. Therefore, the example shown in the seventh (c) is a relief process in which the cobalt plating treatment is the substrate W.

The substrate W after the cobalt plating treatment is washed by the third rinse tank 20b, and transported to the partition chamber 36 by the conveyor 30 together with the substrate holder 42. Then, the substrate W is immersed in pure water in the compartment 36.

As shown in the seventh (d), when the second plating tank 24a is broken in the cleaning process before the substrate W, the relief process for the substrate W is not performed. That is, the activation treatment and the cobalt plating treatment of the substrate W after the front cleaning are not performed. This pre-cleaning treatment is preferred over the activation treatment and cobalt plating treatment. Therefore, the substrate W after the front cleaning is transported to the compartment 36 together with the substrate holder 42 by the conveyor 30, and is immersed in the pure water in the compartment 36. The substrate W after the front cleaning is contained in and received The partition chamber 36 of the substrate W after cobalt-plated plating and the partition chamber 36 which accommodates the partition chamber 36 of the substrate W after gold plating are different. As shown by the dotted arrow in the seventh (d) diagram, the substrate W may not be transported to the compartment 36, but may be immersed in the cleaning liquid (pure water) in the first rinse tank 16b adjacent to the front washing tank 16a. .

As described above, the number of the substrate holders 42 that can be accommodated in the respective compartments 36 of the holder storage tank 14 corresponds to the maximum number of the substrate holders 42 that can be accommodated in the respective processing tanks 16a, 18a, 20a, and 24a. When the electroless plating apparatus fails, the substrate W being processed in each processing tank is transported to the compartment 36 which is previously distributed in the processing tank, and is accommodated. By pre-separating the holder storage tank 14 by each processing tank, it is possible to prevent the micro-processing liquid components adhering to the substrate W and the substrate holder 42 that have undergone different processing steps from reacting with the substrate W to adversely affect the substrate W.

Next, a relief method of the substrate W when the core forming groove 18a fails will be described with reference to the eighth (a) to eighth (d) drawings. Figs. 8(a) to 8(d) are diagrams showing the relief process of the substrate W when the core forming groove 18a fails.

When the core forming groove 18a fails, first, the unprocessed substrate W in the substrate loader 10 is stopped to load the substrate holder 42. Next, the pure water supply and discharge mechanism 35 supplies pure water in the holder storage tank 14. Then, the operation control unit 3 determines whether or not the relief process for performing the higher priority processing on the substrate W can be performed in accordance with the priority order of the memory. When the operation control unit 3 determines that the relief process can be performed, the substrate W is subjected to a relief process, and then the substrate W is immersed in the pure water in the holder storage tank 14.

As shown in the eighth (a) diagram, when the core forming groove 18a fails in the gold plating process of the substrate W, the gold plating process of the substrate W is completed. The gold-plated substrate W is transferred to the partition chamber 36 together with the substrate holder 42 by the conveyor 30, and the substrate W is immersed in the pure water in the compartment 36. The substrate W may be immersed in the fourth rinsing tank 24b as indicated by the dotted arrow in the eighth (a) diagram. In the cleaning liquid (pure water), the substrate W is then transferred to the compartment 36.

As shown in the eighth (b), when the core forming groove 18a is broken in the cobalt plating process of the substrate W, since the cobalt plating process is not affected by the failure of the core forming groove 18a, the cobalt plating of the substrate W is completed. . The substrate W in the first plating tank 20a is transferred to the third rinse tank 20b, and the substrate W is immersed in the washing liquid (pure water) in the third rinse tank 20b. Then, the substrate W is transferred to the second plating tank 24a together with the substrate holder 42 by the conveyor 30, and the substrate W is immersed in the gold plating solution to gold-plated the substrate W. The stability of the substrate W after gold plating to pure water is higher than that of the substrate W after cobalt plating. Therefore, the gold plating treatment shown in the eighth (b) is a relief process of the substrate W.

The gold-plated substrate W is transferred to the compartment 36 by the conveyor 30 and immersed in pure water in the compartment 36. As shown by the dotted arrow in the eighth (b) diagram, the substrate W may be immersed in the cleaning liquid (pure water) in the fourth rinse tank 24b, and then the substrate W may be transferred to the partition chamber 36.

As shown in the eighth (c), when the core forming groove 18a fails in the activation process of the substrate W, the substrate W cannot enter the next processing step as long as the activation process of the substrate W is not completed. Therefore, at this time, the substrate W is transported to the compartment 36 without performing the relief process. The substrate W is housed in a partition chamber 36 different from the partition chamber 36 in which the substrate W subjected to the treatment other than the activation treatment is accommodated.

As shown in the eighth (d), when the core forming groove 18a is broken in the cleaning process before the substrate W, the substrate W cannot enter the next processing step as long as the cleaning process before the substrate W is not completed. Therefore, at this time, the substrate W is transported to the partition chamber 36 without performing the relief process. The substrate W is housed in a compartment 36 different from the compartment 36 in which the substrate W subjected to the processing other than the pre-cleaning process is accommodated. As shown by the dotted arrow in the eighth (d) diagram, the substrate W may be immersed in the cleaning liquid in the first rinse tank 16b adjacent to the front cleaning tank 16a without being conveyed to the partition chamber 36.

According to the present embodiment, the substrate W is immersed in the pure water in the holder storage tank 14 in a state where the stability of the pure water is as high as possible. As a result, the number of substrates W that become defective products can be reduced.

The substrate W is taken out from the pure water in the holder storage tank 14, and the substrate W is dried by the spin rinse dryer 6, and when the substrate W is returned to the wafer cassette by the substrate transfer robot 12, the substrate transfer robot 12 The increase in motion results in a delay in the relief of all substrates. Therefore, the substrate W is stored in the pure water in the holder storage tank 14 while the substrate W is held by the substrate holder 42.

When the electroless plating apparatus is returned to the normal operation state, the pure water in the holder storage tank 14 is discharged through the discharge line 77, and the processing of the substrate W is resumed.

When the relief process of the substrate W is the cobalt plating of the substrate W, it is preferable to form a cobalt film thicker than the predetermined target thickness on the surface of the substrate W. When a plurality of substrates W are plated with cobalt, the plating time of these substrates W is controlled so as to form a cobalt film of the same thickness on all of the substrates W. Specifically, the operation control unit 3 controls the time during which the substrate holder transport mechanism 70 transports the substrate W so that the immersion time of the plating liquid is equal to all the substrates W.

When the cobalt-plated substrate W is immersed in pure water, a cobalt oxide film is formed on the surface of the substrate W. Therefore, after the relief process of the substrate W, the substrate W is transferred to the cobalt oxide film removing device 80 (refer to the first figure). ). The cobalt oxide film removing device 80 is, for example, a device for removing a cobalt oxide film by a hydrogen reduction method. The substrate W is heated by the hydrogen atmosphere gas in the cobalt oxide film removing device 80 to remove the cobalt oxide film. After the cobalt oxide film is removed, the substrate W is transferred to the etching apparatus 81 (refer to the first drawing). The cobalt film having a thickness higher than the target thickness is etched in such a manner as to reach the target thickness. The etching of the substrate W can also be performed by an etching device (not shown) provided outside the electroless plating device. The substrate W after the etching is transferred to the second plating tank 24a to perform gold plating treatment.

The plating reaction depends on the temperature of the plating solution. When the heater for heating the plating solution fails, the temperature of the plating solution gradually decreases, and the plating rate accompanying the plating solution also decreases. Therefore, the thickness of the metal film formed on the substrate W cannot be estimated from the plating time of the substrate W. . Therefore, the film thickness measuring device 82 for measuring the thickness of the metal film should be used to measure the thickness of the metal film formed on the substrate W. The film thickness measuring device 82 is, for example, a non-contact film thickness measuring device using fluorescent X-rays. The thickness of the metal film formed on the substrate W is measured by the film thickness measuring device 82, and the thickness of the metal film to be added or removed is determined in accordance with the measured thickness of the metal film. When the thickness of the metal film measured is less than the target thickness, the substrate W is plated again. When the thickness of the metal film is determined to be higher than the target thickness, the metal film is etched by the etching device 81.

The embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit and scope of the invention.

14‧‧‧Retainer storage slot

16a‧‧‧ before cleaning tank

16b‧‧‧First rinse tank

18a‧‧‧nuclear forming trough

18b‧‧‧Second rinse tank

20a‧‧‧First plating tank

20b‧‧‧3rd rinse tank

24a‧‧‧Second plating tank

24b‧‧‧fourth flushing tank

36‧‧ ‧ compartment

W‧‧‧Substrate

Claims (5)

An operation method of an electroless plating apparatus, comprising: a substrate holder for holding a substrate; a plurality of processing tanks for performing a plurality of processes including electroless plating; and a holder The storage tank is configured to store the substrate holder when the substrate is not held, and the electroless plating device stores the predetermined processing priority according to the stability of the treated substrate to the pure water, and the plurality of processes are performed. When any one of the tanks fails, pure water is supplied to the holder storage tank to determine whether or not a relief process for performing a higher priority process on the substrate can be performed, and in the case of the relief process, after the relief process is performed When the substrate holder holding the substrate is immersed in the pure water in the holder storage tank, and the relief process cannot be performed, the substrate holder holding the substrate is immersed in the above without performing the relief step. The holder holds the pure water in the tank. The method of operating an electroless plating apparatus according to claim 1, wherein the pure water is a deaerated water having a low dissolved oxygen concentration. The method of operating an electroless plating apparatus according to claim 1, wherein the relief step is an electroless plating step of forming a metal film thicker than a predetermined target thickness on a surface of the substrate. The method of operating an electroless plating apparatus according to claim 3, wherein the metal film is a cobalt film. The method for operating an electroless plating apparatus according to claim 1 of the patent scope, wherein the foregoing plurality The treatment includes: cleaning before the substrate, activation treatment of the substrate, and electroless plating of the substrate.