TWI720503B - Electroless plating method, electroless plating apparatus, and program product - Google Patents

Abstract

In an electroless plating, a step of forming a liquid layer of a plating liquid which covers an upper surface (91) of a substrate (9) in horizontal state is performed by ejecting the plating liquid toward the upper surface (91) from a mixing nozzle (31). Subsequently, a step of promoting an electroless plating reaction on the upper surface (91) is performed by starting to heat the liquid layer with a heater (41) in a state where the mixing nozzle (31) stops ejecting the plating liquid to the upper surface (91) and the liquid layer is held on the upper surface (91). It is therefore possible to improve a uniformity of thickness of the plating layer.

Description

Electroless plating method, electroless plating device and program product

The invention relates to an electroless plating method, an electroless plating device and a programmed product.

In recent years, attempts have been made to apply electroless plating to semiconductor substrates (hereinafter referred to as "substrates") in the manufacture of semiconductor devices. For example, in the electroless plating apparatus of Japanese Patent Laid-Open No. 2006-111938 (Document 1), the electroless plating solution is divided into a first chemical solution containing a metal salt and a second chemical solution containing a reducing agent. After starting the processing of one substrate, the two chemical liquids are mixed while moving to the processing of the next substrate. Then, by using this mixed mixed solution (electroless plating solution) in the treatment of the next substrate, stable plating treatment can be performed.

However, in the apparatus of Document 1, the plating solution to be supplied to the substrate is heated to become an active state. In the case that the plating solution is continuously ejected from the nozzle onto the substrate, the plating solution that touches the surface of the substrate in the ejection position on the substrate is instantly replaced, that is, due to the plating solution on the surface of the substrate. Since the flow rate of the tube becomes larger, it is difficult to perform the electroless plating reaction locally. As a result, on the substrate surface, the thickness of the plating layer differs between the ejection position and other regions, and the uniformity of the thickness of the plating layer becomes low.

[The problem to be solved by the invention]

The present invention focuses on the electroless plating method, and aims to improve the uniformity of the thickness of the plating layer.

The electroless plating method of the present invention includes the step (a) of spraying a plating solution from a nozzle toward one main surface of a substrate in a horizontal state, thereby forming a liquid layer of the plating solution covering the one main surface And step (b), stopping the spraying of the plating solution from the nozzle toward the one main surface and starting the heating of the liquid layer or the shaking of the liquid layer in a state where the liquid layer is maintained on the one main surface, This promotes the electroless plating reaction on the aforementioned one main surface.

According to the present invention, the thickness uniformity of the plating layer can be improved.

In a preferred form of the present invention, the plating solution contains a metal salt of the plating metal and a reducing agent used to reduce and precipitate the ions of the plating metal, and does not contain any usefulness to prevent decomposition of the plating solution. The stabilizer may not contain any dissolving agent.

In this case, it is preferable to mix the first chemical solution containing the metal salt and the second chemical solution containing the reducing agent in the step (a) immediately before spraying the plating solution from the nozzle , Thereby generating the aforementioned plating solution.

In another preferred aspect of the present invention, in the step (a), immediately before spraying the plating solution from the nozzle, the first chemical solution containing the metal salt of the plating metal is mixed with the first chemical solution containing the metal salt to make The ions of the plating metal reduce the deposited second chemical solution of the reducing agent, thereby generating the plating solution.

In one aspect of the present invention, the first chemical liquid and the second chemical liquid are mixed in the nozzle.

In another aspect of the present invention, the first chemical liquid and the second chemical liquid are mixed in a mixing valve connected to the nozzle.

In another aspect of the present invention, the electroless plating method further includes the following steps: after the step (b), spray a cleaning liquid from the nozzle toward the one main surface; before spraying the cleaning liquid, The cleaning liquid passes through a flow path from the mixing position of the first chemical liquid and the second chemical liquid to the ejection port of the nozzle.

In another preferred aspect of the present invention, the electroless plating method further includes: step (c), after the step (b), from the nozzle toward the plating solution on the one main surface The liquid layer sprays a new plating liquid, thereby forming a liquid layer for covering the new plating liquid on the one main surface; and step (d) is to stop spraying the spray from the nozzle toward the one main surface Heating of the liquid layer or shaking of the liquid layer is performed while maintaining the liquid layer of the new plating liquid on the one main surface, thereby promoting electroless electrolysis in the one main surface Plating reaction.

In another preferred form of the present invention, the electroless plating method further includes: step (c), after the step (b), rotating the substrate to remove the liquid layer of the plating solution, Next, a new plating solution is sprayed from the nozzle toward the one main surface, thereby forming a liquid layer for covering the new plating solution on the one main surface; and step (d) is to stop the direction from the nozzle The one main surface is sprayed with the new plating solution and the liquid layer of the new plating solution is maintained on the one main surface, heating the liquid layer or shaking the liquid layer, thereby promoting the one Electroless plating reaction in the main surface.

The electroless plating method may further include a step useful for repeating the aforementioned step (c) and the aforementioned step (d).

In another preferred aspect of the present invention, in the step (a), the heating of the liquid layer by the heater is set to a non-actuated (OFF) state, and in the step (b), the heater is The heating of the aforementioned liquid layer is set to an active (ON) state.

Preferably, the heating of the liquid layer by the heater is set to an inactive state in the step (a) and the step (c), and the heater is set in the step (b) and the step (d). The heating of the aforementioned liquid layer is set to an active state.

For example, the heater is opposed to the other main surface of the substrate; in the actuated state, the heater is arranged at a position close to or in contact with the other main surface; in the non-actuated state, the heating The device is arranged at a position separated from the other main surface.

In another preferred aspect of the present invention, in the step (b), the substrate is rotated while the liquid layer of the plating solution is heated and the liquid layer is held on the one main surface.

In another preferred aspect of the present invention, in the step (b), while the liquid layer of the plating solution is held on the one main surface, the substrate is rotated or vibration is applied to the substrate.

The present invention also focuses on the electroless plating device. The electroless plating device of the present invention is provided with: a substrate holding part that holds the substrate in a horizontal state; and a plating solution supply part that sprays the plating solution from a nozzle toward one main surface of the substrate to form a coating The liquid layer of the plating solution on the one main surface; the plating reaction promotion part is for heating the liquid layer or the shaking of the liquid layer; and the control part is for stopping spraying the spray from the nozzle toward the one main surface Plating solution and start the heating of the liquid layer or the shaking of the liquid layer by the plating reaction promoting portion while maintaining the liquid layer on the one main surface, thereby promoting the electroless plating on the one main surface Overlay reaction.

The present invention also focuses on program products, which allows a computer to control the electroless plating device. The electroless plating device is provided with a substrate holding portion, a plating solution supply portion, and a plating reaction promoting portion.

The above-mentioned objects and other objects, features, aspects, and advantages are made clear by referring to the accompanying drawings and the detailed description of the present invention described below.

Fig. 1 is a diagram showing the configuration of an electroless plating apparatus 1 according to one embodiment of the present invention. The electroless plating device 1 is a blade-type device for processing disk-shaped substrates 9 piece by piece. The electroless plating apparatus 1 includes a substrate holding part 21, a substrate rotating mechanism 22, a cup 23, a plating solution supply part 3, a plating reaction promotion part 4, and a computer 11.

The substrate holding portion 21 has a disk-shaped base portion 211 with a center axis J1 oriented in the vertical direction as its center. A plurality of chuck pins 212 are provided on the upper surface of the base portion 211. The plurality of clamp pins 212 are arranged at equal intervals in the circumferential direction on the circumference with the center axis J1 as the center. Each clamp pin 212 can be rotated with a shaft parallel to the central axis J1 as a center by a pin driving mechanism (not shown). A grip 213 is provided at the tip of the clamp pin 212. When the substrate holding portion 21 holds the substrate 9, the respective clamp pins 212 rotate. Thereby, the plurality of holding parts 213 are pressed to the outer peripheral edge of the substrate 9, and the substrate 9 is held above the base part 211 in a horizontal state. The center of the substrate 9 held by the substrate holding portion 21 is located on the central axis J1. The upper surface of the base portion 211 is parallel to the main surface 92 (hereinafter referred to as the "lower surface 92") facing downward in the substrate 9 and both face each other with a gap therebetween.

The upper end of the shaft portion 221 with the center axis J1 as the center is fixed to the center of the lower surface of the base portion 211. The substrate rotating mechanism 22 with a motor is the lower end portion of the rotating shaft portion 221, whereby the substrate holding portion 21 rotates together with the substrate 9 with the central axis J1 as the center. The cover portion 23 has a substantially cylindrical shape and surrounds the periphery of the base portion 211. In the processing of the substrate 9 described later, various processing liquid systems scattered from the outer peripheral edge of the rotating substrate 9 are caught by the inner peripheral surface of the cover portion 23 and collected. In the electroless plating apparatus 1, the upper part of the cover part 23 can be raised and lowered in the up-and-down direction by the cover part raising and lowering mechanism which is not shown in figure. When carrying in and carrying out the substrate 9 in the electroless plating apparatus 1, the upper part of the cover portion 23 is lowered to prevent the cover portion 23 from interfering with an external transport mechanism.

The plating reaction promotion unit 4 includes a heater 41 and a heater raising and lowering mechanism 42. The heater 41 has a disk shape with a center axis J1 as the center, and is arranged between the substrate 9 held by the substrate holding portion 21 and the base portion 211. The heater 41 is located on one side of the lower surface 92 of the substrate 9. The heater 41 is, for example, a hot plate having a resistance heating element such as a nickel-chromium wire. The heater 41 may use a heat source other than the resistance heating element. The upper surface of the heater 41 covers substantially the entire lower surface 92 of the substrate 9 and directly faces the lower surface 92. The upper surface of the heater 41 is substantially parallel to the lower surface 92 of the substrate 9.

To the center of the lower surface of the heater 41, the upper end of the lift shaft 421 with the center axis J1 as the center is fixed. A hollow portion extending in the vertical direction is provided on the central axis J1 of the base portion 211 and the shaft portion 221, and a lift shaft 421 is arranged in the hollow portion. The lifting shaft 421 extends below the lower end of the shaft portion 221. In the lower part of the shaft portion 221, the lower end portion of the lifting shaft 421 is connected to the heater lifting mechanism 42.

The heater lifting mechanism 42 supports the heater 41 via the lifting shaft 421. For example, the heater lifting mechanism 42 includes a ball screw mechanism and a motor, and is driven by the motor to move the lifting shaft 421 in the vertical direction. Thereby, the heater 41 is selectively arranged in the upper position and the lower position. The upper position is the position where the upper surface of the heater 41 approaches the lower surface 92 of the substrate 9, and the lower position is the upper surface of the heater 41. A position away from the bottom surface 92 of the substrate 9. In the example of FIG. 1, in the lower position, the lower surface of the heater 41 is close to or in contact with the upper surface of the base portion 211. The heater 41 may be arranged at any position between the upper position and the lower position. In this embodiment, the heater 41 is constantly heated at a fixed temperature. By arranging the heater 41 at the upper position, the lower surface 92 of the substrate 9 can be heated substantially uniformly. On the other hand, in the state where the heater 41 is arranged in the lower position, the substrate 9 system is hardly heated. In the case where the substrate 9 is not rotated when the substrate 9 is heated, the upper surface of the heater 41 may also contact the lower surface 92 of the substrate 9 in the upper position.

The plating solution supply unit 3 includes a mixing nozzle 31, a first chemical solution supply source 33, a second chemical solution supply source 34, and a cleaning solution supply source 35. The mixing nozzle 31 is opposed to the main surface 91 (hereinafter referred to as the "upper surface 91") facing upward in the substrate 9. Specifically, the mixing nozzle 31 is arranged above the central portion of the upper surface 91, and the ejection port 312 of the mixing nozzle 31 directly faces the upper surface 91. The mixing nozzle 31 has a mixing chamber 311 and the aforementioned ejection port 312. A first medical solution supply source 33 is connected to the mixing chamber 311 via a first medical solution supply pipe 331, and a second medical solution supply source 34 is connected via a second medical solution supply pipe 341. In addition, a cleaning liquid supply source 35 is connected to the mixing chamber 311 via a cleaning liquid supply pipe 351. The first chemical solution supply pipe 331 is provided with a flow rate adjustment valve 332 and an on-off valve 333 in this order from the side of the first chemical solution supply source 33 toward the mixing nozzle 31. The second chemical liquid supply pipe 341 is provided with a flow rate adjusting valve 342 and an on-off valve 343 in this order from the side of the second chemical liquid supply source 34 toward the mixing nozzle 31. An on-off valve 353 is provided in the cleaning liquid supply pipe 351.

As described later, in the plating solution supply unit 3, the first chemical solution is supplied from the first chemical solution supply source 33 into the mixing chamber 311 and the second chemical solution is supplied from the second chemical solution supply source 34 into the mixing chamber 311. Two liquid medicine. The first chemical solution contains the metal salt of the plated metal in the electroless plating. The plating metal system is, for example, nickel (Ni), copper (Cu), cobalt (Co), cobalt tungsten boron (CoWB), gold (Au), or silver (Ag). The second chemical solution contains a reducing agent for reducing and depositing ions of the plated metal. The reducing agent system is, for example, DMAB (boron compound) and the like. The first chemical solution and the second chemical solution are mixed in the mixing chamber 311, thereby generating a plating solution containing the above-mentioned metal salt and a reducing agent.

The plating solution is sprayed from the spray port 312 continuous to the mixing chamber 311 toward the center of the upper surface 91 of the substrate 9, for example, in a columnar shape. The mixing ratio of the first chemical solution and the second chemical solution in the plating solution is adjusted by controlling the opening degree of the flow rate adjusting valves 332 and 342. Preferably, both the first chemical solution and the second chemical solution do not contain a stabilizer useful to prevent the decomposition of the plating solution (for example, a mixed solution in which an alkyl alcohol is added to a carboxylic acid, etc.) or does not contain a dissolving agent (For example, a mixed solution containing ethylenediamine, etc.). In this case, the plating solution generated in the mixing nozzle 31 also does not contain a stabilizer or a complexing agent. More preferably, the plating solution system does not include both a stabilizer and a complexing agent. The plating solution may also include a ph adjuster (such as ammonia, etc.) that is useful for preparing the ph (power of hydrogen; acid-base value) of the plating solution, and a buffer (such as ammonia, etc.) to suppress changes in ph.

In this embodiment, the first chemical solution supply source 33 and the first chemical solution supply pipe 331 are not provided with a heater for heating the first chemical solution. In addition, the second chemical solution supply source 34 and the second chemical solution supply pipe 341 are not provided with a heater for heating the second chemical solution. Furthermore, a heater is not provided in the mixing nozzle 31 either. Therefore, the plating solution at a substantially normal temperature is ejected from the mixing nozzle 31 toward the upper surface 91 of the substrate 9. The temperature of the plating solution sprayed from the mixing nozzle 31 is, for example, 23°C to 40°C.

In the plating liquid supply unit 3, the cleaning liquid is supplied from the cleaning liquid supply source 35 into the mixing chamber 311 of the mixing nozzle 31, and the cleaning liquid is ejected from the ejection port 312 toward the center of the upper surface 91 of the substrate 9. When the cleaning liquid is supplied to the mixing nozzle 31, the first chemical liquid and the second chemical liquid are not supplied into the mixing chamber 311. The cleaning liquid system is pure water, for example. A cleaning solution other than pure water can also be used.

The electroless plating apparatus 1 is further provided with a processing liquid supply part 5. The processing liquid supply unit 5 includes an auxiliary nozzle 51, a catalyst solution supply source 52, a cleaning liquid supply source 53, and a cleaning liquid supply source 54. The auxiliary nozzle 51 is arranged above the substrate 9. A catalyst solution supply source 52, a cleaning solution supply source 53, and a cleaning solution supply source 54 are respectively connected to the auxiliary nozzle 51 via a valve. By supplying the catalyst solution from the catalyst solution supply source 52 to the auxiliary nozzle 51, the catalyst solution is ejected from the auxiliary nozzle 51 toward the center of the upper surface 91 of the substrate 9. The catalyst solution is a solution containing a catalyst (for example, metal ions such as palladium (Pd)) that is useful for electroless plating.

In addition, by supplying the cleaning liquid from the cleaning liquid supply source 53 to the auxiliary nozzle 51, the cleaning liquid is sprayed from the auxiliary nozzle 51 toward the center portion of the upper surface 91 of the substrate 9. The cleaning liquid system is, for example, DHF (dilute hydrofluoric acid; dilute hydrofluoric acid). The cleaning liquid is supplied from the cleaning liquid supply source 54 to the auxiliary nozzle 51, whereby the cleaning liquid is sprayed from the auxiliary nozzle 51 toward the center of the upper surface 91 of the substrate 9. The cleaning liquid system is pure water, for example. In the processing liquid supply part 5, other processing liquids, such as an etching liquid, can also be used. The catalyst solution supply source 52, the cleaning solution supply source 53, and the cleaning solution supply source 54 may also be connected to different nozzles, respectively. In addition, the cleaning liquid supply source 35 of the plating liquid supply part 3 may also serve as the cleaning liquid supply source 54.

In the electroless plating apparatus 1, a nozzle moving mechanism for moving the mixing nozzle 31 and the auxiliary nozzle 51 may also be provided. The nozzle moving mechanism selectively arranges the mixing nozzle 31 and the auxiliary nozzle 51 at the opposing position and the standby position. The opposing position is a position opposing the upper surface 91 of the substrate 9, and the standby position is facing away from the substrate 9. The position to leave in the horizontal direction. The nozzle moving mechanism may also move the mixing nozzle 31 and the auxiliary nozzle 51 individually.

FIG. 2 is a diagram showing the structure of the computer 11. The computer 11 has become a general computer system and includes: CPU (Central Processing Unit; central processing unit) 111, which performs various calculations; ROM (Read Only Memory) 112, which stores basic programs ; And RAM (Random Access Memory; random access memory) 113, which stores various information. The computer 11 system further includes: a fixed hard disk 114 for information storage; a display unit 115 for displaying various information; a keyboard 116a and a mouse 116b as an input unit 116 for receiving input from an operator; reading The writing device 118 reads information from a computer-readable recording medium 81 such as optical discs, magnetic disks, and optical magnetic discs, and writes information to the recording medium 81; and the communication unit 119, which is compatible with electroless The components of the plating device 1 communicate.

In the computer 11, the program 810 is read in advance from the recording medium 81 belonging to the program product via the reader/writer 118 and stored in the fixed hard disk 114. Then, the CPU 111 uses the RAM 113 and the fixed hard disk 114 to execute arithmetic processing (ie, the computer executes the program) according to the program 810, whereby the computer 11 functions as the control unit 110 in the electroless plating apparatus 1 of FIG. 1. In the electroless plating apparatus 1, the control unit 110 is responsible for overall control. The control unit 110 may also be constructed by a dedicated electrical circuit, or a dedicated electrical circuit may be used locally.

FIG. 3 is a diagram showing the flow of the electroless plating process in the electroless plating device 1. In the electroless plating process, control of the electroless plating apparatus 1 is performed by the control section 110 of FIG. 1 (except for the control section 110, control of each configuration of the electroless plating apparatus 1 is performed).

In the electroless plating apparatus 1, the substrate 9 to be processed is carried in by an external transport mechanism in advance, and the substrate 9 is held by the substrate holding portion 21. In the electroless plating process, first, the substrate 9 is rotated by the substrate rotating mechanism 22. The substrate 9 is rotated together with the substrate holding portion 21 in a horizontal state. In addition, the cleaning liquid is supplied to the center portion of the upper surface 91 of the substrate 9 from the cleaning liquid supply source 53 via the auxiliary nozzle 51 arranged at the opposite position (step S11).

In the upper surface 91, the centrifugal force of the cleaning liquid caused by the rotation of the substrate 9 expands toward the outer periphery of the substrate 9, and the cleaning liquid is supplied to the entire upper surface 91. The washing liquid scattered from the outer peripheral edge of the substrate 9 is caught by the inner peripheral surface of the cover portion 23 and collected (the same applies to the supply of the washing liquid, the catalyst solution, and the plating liquid described later). With the supply of the cleaning solution, foreign matter and natural oxide film on the upper surface 91 are removed. The spraying of the cleaning liquid continues for a predetermined time.

When the spraying of the cleaning liquid is stopped, the cleaning liquid is supplied from the cleaning liquid supply source 54 to the center portion of the upper surface 91 via the auxiliary nozzle 51 (step S12). In the upper surface 91, the cleaning liquid is spread toward the outer periphery of the substrate 9 by the rotation of the substrate 9, and the cleaning liquid is supplied to the entire upper surface 91. By the supply of the cleaning liquid, the cleaning liquid adhering to the upper surface 91 is removed. After the cleaning fluid system continues to spray for a predetermined time, the spraying of the cleaning fluid is stopped.

Next, the catalyst solution is supplied to the center part of the upper surface 91 from the catalyst solution supply source 52 via the auxiliary nozzle 51 (step S13). In the upper surface 91, the catalyst solution spreads toward the outer periphery of the substrate 9 by the rotation of the substrate 9, and the catalyst solution is supplied to the entire upper surface 91. Thereby, a catalyst (for example, palladium) is adsorbed to the upper surface 91 to form a catalyst layer. The ejection of the catalyst solution continues for a predetermined time.

When the ejection of the catalyst solution is stopped, the cleaning liquid is supplied from the cleaning liquid supply source 54 to the center portion of the upper surface 91 via the auxiliary nozzle 51 (step S14). In the upper surface 91, the cleaning liquid is spread toward the outer periphery of the substrate 9 by the rotation of the substrate 9, and the cleaning liquid is supplied to the entire upper surface 91. By the supply of the cleaning liquid, the catalyst solution adhering to the upper surface 91 is removed. In addition, the catalyst layer formed on the upper surface 91 is maintained. After the cleaning fluid system continues to spray for a predetermined time, the spraying of the cleaning fluid is stopped.

Next, the supply of the first chemical solution from the first chemical solution supply source 33 into the mixing chamber 311 of the mixing nozzle 31 is started, and the supply of the second chemical solution from the second chemical solution supply source 34 into the mixing chamber 311 is started. The first chemical solution and the second chemical solution are mixed in the mixing chamber 311 to generate a plating solution. The mixing nozzle 31 is arranged at an opposing position, and the plating solution is continuously ejected from the ejection port 312 of the mixing nozzle 31 toward the center portion of the upper surface 91 of the substrate 9. In the upper surface 91, the plating solution spreads toward the outer periphery of the substrate 9 by the rotation of the substrate 9, and the plating solution is supplied to the entire upper surface 91.

At this time, since the number of rotations of the substrate 9 is low, a liquid layer 93 (also referred to as a paddle) with a plating liquid covering the entire upper surface 91 is formed as shown in FIG. 4A (step S15). That is, the upper surface 91 contains a plating solution. In FIG. 4A, the rotation of the substrate 9 is indicated by the arrow A1 (the same applies to FIGS. 4C, 4E, 4F, 5A, and 5B described later). As mentioned above, the plating solution is approximately room temperature. In addition, the heater 41 is arranged at a position separated from the lower surface 92 of the substrate 9. Therefore, the temperature of the plating liquid contained in the liquid layer 93 is maintained at approximately normal temperature, and the electroless plating reaction on the upper surface 91 becomes a suppressed state, that is, a state in which the reaction rate is low (inert state). As described later, the heater 41 is arranged close to the position above the lower surface 92, whereby the heater 41 is in an active state for heating the liquid layer 93, so the heater 41 is arranged below the lower surface 92 after being separated from the lower surface 92. In step S15 of the position, the heating of the liquid layer 93 by the heater 41 is in an inactive state.

In the plating solution supply section 3, during the period during which the plating solution is continuously sprayed from the mixing nozzle 31 (the processing period of step S15), the total amount (volume) of the plating solution generated in the mixing chamber 311 is much larger than The volume of the mixing chamber 311. Therefore, most of the plating solution generated by the mixing of the first chemical solution and the second chemical solution in the aforementioned period is ejected toward the substrate 9 during the aforementioned period. In other words, in the electroless plating apparatus 1, immediately before spraying the plating solution from the mixing nozzle 31, the first chemical solution and the second chemical solution are mixed to generate the plating solution.

In the case where the diameter of the substrate 9 is 300 mm and the plating solution is sprayed from the mixing nozzle 31 at a flow rate of 0.05 L (liter) to 0.3 L per minute, a certain thickness of the plating solution layer 93 is appropriately formed. From a standpoint, the number of rotations of the substrate 9 is preferably 300 rpm or less. In the electroless plating apparatus 1, the liquid layer 93 of the plating solution can be formed in a state where the rotation of the substrate 9 has been stopped. In this case, the plating solution continuously supplied to the center of the upper surface 91 gradually spreads toward the outer periphery of the substrate 9, and a liquid layer 93 of the plating solution is formed on the entire upper surface 91. As described above, the number of rotations of the substrate 9 when forming the liquid layer 93 of the plating solution (hereinafter referred to as "the number of rotations for liquid layer formation") is preferably 0 rpm to 300 rpm. The number of rotations for liquid layer formation is preferably 0 rpm to 50 rpm, more preferably 0 rpm to 10 rpm. In addition, the flow rate of the plating solution is preferably 0.05L to 0.3L per minute. In the following description, the rotation number of the substrate 9 in the liquid layer formation rotation system includes the case where the rotation number of the substrate 9 is 0, that is, the case where the rotation of the substrate 9 is stopped.

When the plating solution is sprayed for a predetermined time and the plating solution layer 93 is formed, the spraying of the plating solution from the mixing nozzle 31 is stopped. In the upper surface 91, the liquid layer 93 is maintained by the surface tension of the plating liquid. Then, the heater 41 is raised by the heater lifting mechanism 42 and is arranged close to the position above the lower surface 92 of the substrate 9 as shown in FIG. 4B. Thereby, the heater 41 starts to heat the substrate 9. By the heating of the substrate 9, the liquid layer 93 is also heated. In this way, by arranging the heater 41 at the upper position, the heating system of the heater 41 with respect to the liquid layer 93 becomes an active state.

The temperature of the plating solution contained in the solution layer 93 rises, whereby the plating solution becomes an active state (a state where the reaction rate is high), and the electroless plating reaction in the entire upper surface 91 is promoted (step S16). For example, the plating solution contained in the liquid layer 93 is heated to 40°C to 60°C. In the electroless plating reaction, the reducing agent contained in the plating solution is oxidized by the catalytic action of the catalyst layer formed on the upper surface 91, and the ion of the plating metal contained in the plating solution is It is reduced by electrons from the reducing agent, and the plating metal is deposited on the catalyst layer. In addition, the reducing agent is oxidized by the catalytic action of the deposited plating metal itself, and further reduces and deposits ions of the plating metal. In the electroless plating apparatus 1, the lower surface 92 of the substrate 9 is uniformly heated, and the electroless plating reaction is promoted simultaneously in the entire upper surface 91. Thereby, the plating metal grows uniformly in the whole upper surface 91, and the uniform plating layer 94 is formed (refer FIG. 4C mentioned later). The film formation rate in step S16 is, for example, 5 times or more (corresponding to the entire film) of the film formation rate in step S15 (the film formation rate in a state where the reaction is suppressed).

In an example of the substrate 9, a plurality of vertical pattern elements are formed on the upper surface 91, and the plating layer 94 is formed on the surface of the pattern elements. At this time, when focusing on the minute gaps between adjacent pattern elements, when the plating metal and reducing agent of the plating solution existing in the gaps are consumed, the electroless plating reaction cannot be performed in the gaps. . Therefore, it is preferable to rotate the substrate 9 in the electroless plating apparatus 1 at the number of revolutions (for example, the number of revolutions less than 300 rpm) of the liquid layer 93 that can hold the plating solution on the upper surface 91, so that the gap will exist. The plating solution is slowly replaced with the surrounding plating solution. In this way, the substrate 9 is rotated while the liquid layer 93 of the plating solution is heated and the liquid layer 93 is maintained on the upper surface 91, whereby the electroless plating reaction can be further promoted, and the unnecessary Consumption) Utilize plating solution. On the other hand, from the viewpoint of more surely maintaining the liquid layer 93 on the upper surface 91 when the electroless plating reaction in the upper surface 91 is promoted, the rotation of the substrate 9 may also be stopped. The rotation number system of the substrate 9 in step S16 is, for example, 0 rpm to 300 rpm, preferably 0 rpm to 50 rpm, and more preferably 0 rpm to 10 rpm.

When the heater 41 starts to heat the liquid layer 93 for a predetermined time, the heater 41 is lowered by the heater lifting mechanism 42 and arranged at a position that has been separated from the lower surface 92 of the substrate 9 (refer to FIG. 4C described later). Thereby, the heating of the substrate 9 by the heater 41 is substantially stopped. In other words, the heating system of the heater 41 to the liquid layer 93 becomes in an inactive state. Next, it is confirmed whether or not the processing of steps S15 and S16 described above is repeated. In the control unit 110, the set value of the number of repetitions of steps S15 and S16 is input in advance, and it is confirmed whether the actual number of repetitions has reached the set value. When the actual number of repetitions has not reached the set value (step S17), while the substrate 9 is rotated with the number of rotations of the liquid layer, as shown in FIG. 4C, from the mixing nozzle 31 toward the plating solution on the upper surface 91 Layer 93 sprays new plating solution. In FIG. 4C, the width of the parallel diagonal lines attached to the liquid layer 93 is reduced to be narrower than that of FIGS. 4A and 4B, and the used liquid layer 93 is shown. By spraying a new plating solution from the mixing nozzle 31, a liquid layer 93a (refer to FIG. 4D described later) to cover the upper surface 91 with a new plating solution is formed (step S15). As described above, since the heating of the liquid layer 93a by the heater 41 is in an inactive state, the electroless plating reaction system in the upper surface 91 is suppressed.

At this time, the new plating solution may include a part of the plating solution generated in the mixing chamber 311 during the process of the previous step S15 (at the time of the formation of the solution layer 93 of the initial plating solution). In the electroless plating process, at least a part of the plating solution generated by the mixing of the first chemical solution and the second chemical solution in the processing period of each step S15 is sprayed toward the substrate 9 during the processing period. In this case, the plating solution can be generated just before spraying from the mixing nozzle 31.

After a new plating solution is sprayed from the mixing nozzle 31 toward the upper surface 91 for a predetermined time, the spraying of the new plating solution is stopped. Next, the heater 41 is raised by the heater lifting mechanism 42 and is arranged at a position close to the upper surface of the lower surface 92 of the substrate 9 as shown in FIG. 4D. Thereby, heating of the liquid layer 93a is started while the liquid layer 93a has been maintained in the upper surface 91 (that is, the heating of the liquid layer 93a by the heater 41 is set to an active state), and the electroless plating on the upper surface 91 is promoted. Overlay reaction (step S16). By using the electroless plating for the liquid layer 93a of the upper surface 91, the thickness of the plating layer 94 on the upper surface 91 is uniformly increased. When a predetermined time has elapsed since the start of heating the liquid layer 93a, the heater 41 is lowered to stop heating the liquid layer 93a. In the electroless plating apparatus 1, the processes of the above-mentioned steps S15 and S16 are repeated until the actual number of repetitions of the steps S15 and S16 reaches the set value (step S17). Thereby, the thickness of the plating layer 94 is further increased.

When the actual number of repetitions of steps S15 and S16 reaches the set value (step S17), the cleaning liquid is supplied to the mixing nozzle 31 from the cleaning liquid supply source 35. Thereby, as shown in FIG. 4E, the cleaning liquid is sprayed from the mixing nozzle 31 toward the center part of the upper surface 91 (step S18). In the upper surface 91, the cleaning liquid is spread toward the outer periphery of the substrate 9 by the rotation of the substrate 9, and the cleaning liquid is supplied to the entire upper surface 91. By the supply of the cleaning liquid, the plating liquid adhering to the upper surface 91 is removed. At this time, in the mixing nozzle 31 of FIG. 1, the cleaning liquid is filled into the mixing chamber 311 and then ejected from the ejection port 312. Therefore, the plating liquid remaining in the mixing chamber 311 is removed by the cleaning liquid passing through the mixing chamber 311. After spraying the cleaning liquid for a predetermined time, stop spraying the cleaning liquid.

Next, the substrate rotating mechanism 22 sets the number of rotations of the substrate 9 to be higher than when the cleaning liquid is supplied, thereby starting the drying process (spin drying) of the substrate 9 as shown in FIG. 4F (step S19). The cleaning liquid adhering to the upper surface 91 is removed by a drying process. When the drying process is finished, the rotation of the substrate 9 is stopped. After that, the substrate 9 is carried out from the electroless plating apparatus 1 by an external transport mechanism. Thereby, the processing of the substrate 9 in the electroless plating apparatus 1 is completed.

Here, the electroless plating apparatus of the comparative example will be described. In the electroless plating apparatus of the comparative example, a heated plating solution is sprayed from a nozzle toward the upper surface 91 of the substrate 9. In the electroless plating apparatus of the comparative example, since the plating solution is ejected from the nozzle in a state of being activated by heating, the electroless plating reaction is performed by the spreading plating solution on the upper surface 91. On the other hand, in the position (spraying position) on the upper surface 91 where the plating solution sprayed from the nozzle collides, the plating solution contacting the upper surface 91 is instantly replaced, that is, the plating solution in the upper surface 91 The flow rate becomes larger. As a result, in the ejection position on the upper surface 91, it becomes difficult to locally proceed the electroless plating reaction (the plating metal becomes difficult to grow), and the uniformity of the thickness of the plating layer becomes low.

On the other hand, in the treatment of the electroless plating apparatus 1, the following step is performed: a plating solution at room temperature is sprayed from the mixing nozzle 31 to form a liquid layer for covering the upper surface 91 of the plating solution. Next, the following process is performed: the spraying of the plating solution from the mixing nozzle 31 toward the upper surface 91 is stopped and the liquid layer is maintained on the upper surface 91 to start heating the liquid layer, thereby promoting electroless in the upper surface 91 Plating reaction. In this way, when the plating solution is sprayed from the mixing nozzle 31, the electroless plating reaction is suppressed in the entire upper surface 91, and the heating of the substrate 9 is promoted in the entire upper surface 91 after the liquid layer of the plating solution is formed. The electroless plating reaction suppresses the difference in the growth of the plating metal between the ejection position and other regions, and can improve the uniformity of the thickness of the plating layer.

In addition, the following step is performed after the above steps: a new plating solution is sprayed from the mixing nozzle 31 toward the above-mentioned liquid layer on the upper surface 91 to thereby form a new plating liquid layer for covering the upper surface 91. Next, the following process is performed: the spraying of new plating liquid from the mixing nozzle 31 toward the upper surface 91 is stopped and the liquid layer is maintained on the upper surface 91 to start heating the liquid layer, thereby promoting the liquid layer in the upper surface 91 Electroless plating reaction. Thereby, a uniform and thick plating layer can be formed.

In addition, in the case where the plating solution contains a stabilizer or a complexing agent, the stabilizer or complexing agent is adsorbed to the catalyst layer formed on the upper surface 91 and hinders the catalytic action of the catalyst layer. When the reducing agent is oxidized, that is, there will be stabilizers or complexing agents that act as catalyst toxins. In this case, it becomes impossible to form a plating layer properly.

In contrast, in a preferable electroless plating treatment, a plating solution that does not contain a stabilizer or a complexing agent can be used. Thereby, it is possible to suppress the inhibition of oxidation of the reducing agent, and to form a plating layer appropriately. In a more preferable electroless plating process, the plating solution does not contain both the stabilizer and the dissolving agent, so that the inhibition of the oxidation of the reducing agent can be further suppressed. In addition, the omission of stabilizers or modifiers can reduce the cost required for the production of the plating solution. Depending on the type of the plating solution, etc., the plating solution may also contain a stabilizer or a complexing agent.

In the case where a tank for storing the plating solution is used, in order to maintain the concentration of the plating solution in the tank constant, a concentration monitor and/or a liquid replenishing system, etc. are required. In addition, in order to stabilize the properties of the plating solution in the tank, it is also necessary to add a stabilizer or a complexing agent. Furthermore, there is a possibility that the inside of the pipe connecting the groove and the nozzle may be plated.

In contrast, in the electroless plating apparatus 1 of FIG. 1, immediately before spraying the plating solution from the mixing nozzle 31, the first chemical solution and the second chemical solution are mixed in the mixing nozzle 31 to generate the plating solution. This prevents the inside of the first chemical liquid supply pipe 331 connecting the first chemical liquid supply source 33 and the mixing nozzle 31 and the second chemical liquid supply pipe 341 connecting the second chemical liquid supply source 34 and the mixing nozzle 31 Is plated. In addition, there is no need to provide a concentration monitor, a liquid replenishing system, etc., and a plating liquid in which a metal salt and a reducing agent are uniformly mixed can be easily supplied to the substrate 9 in a required amount. As a result, it is possible to reduce the manufacturing cost of the electroless plating device 1 and reduce the running cost due to the saving of the plating solution. Furthermore, it is also possible to suppress adverse effects (such as deterioration of the plating solution, etc.) due to the absence of stabilizers or dissolving agents in the plating solution.

In addition, when the cleaning liquid is sprayed from the mixing nozzle 31, the cleaning liquid passes through the flow path from the mixing position of the first chemical liquid and the second chemical liquid (the mixing chamber 311 in FIG. 1) to the discharge port 312 of the mixing nozzle 31. Thereby, the plating solution remaining in the path from the mixing position to the ejection port 312 can be removed by the cleaning solution, and the flow path can be prevented from being plated. Of course, according to the design of the electroless plating device 1, a tank for storing the plating solution can also be adopted.

In the electroless plating apparatus 1, in the active state of heating of the liquid layer, the heater 41 is arranged at a position close to or in contact with the lower surface 92 of the substrate 9; in the inactive state of heating of the liquid layer, the heater 41 is 41 is arranged at a position separated from the lower surface 92. This makes it possible to use the heater 41 whose temperature is difficult to rise and fall sharply, so that the active state and the non-actuated state of heating the liquid layer can be switched appropriately.

In the above processing example, when the processing of steps S15 and S16 is repeated, although a new plating solution is sprayed from the mixing nozzle 31 toward the plating solution layer 93 on the upper surface 91, a new plating solution may be sprayed. The liquid layer 93 on the upper surface 91 is removed before the liquid. In this case, in step S15 repeated by step S17, the substrate 9 is rotated at a rotation number higher than the rotation number of the liquid layer formation, thereby removing the liquid layer 93 on the upper surface 91 as shown in FIG. 5A . At this time, the heater 41 is arranged in the lower position. Next, while the substrate 9 is rotated by the number of revolutions of the liquid layer formation, a new plating solution is sprayed from the mixing nozzle 31 toward the upper surface 91, thereby forming a new plating solution that can cover the upper surface 91 as shown in FIG. 5B的液层93a.

In step S16, as shown in FIG. 5C, the heater 41 stops spraying the new plating solution toward the upper surface 91 from the mixing nozzle 31 and maintains the new plating solution layer 93a on the upper surface 91. The system is configured in the upper position. Thereby, the heating system of the heater 41 with respect to the liquid layer 93a is set to an active state, and the electroless plating reaction in the upper surface 91 is promoted. As a result, the thickness of the plating layer 94 in the upper surface 91 is increased. The processing of the above steps S15 and S16 is further repeated as needed.

In the processes of steps S15 and S16 described above, the substrate 9 is rotated at a high number of rotations before spraying a new plating solution, whereby the liquid layer 93 of the used plating solution can be removed and the temperature of the substrate 9 can be lowered. Thereby, when a new plating solution liquid layer 93a is formed, the temperature of the substrate 9 and the plating solution can be kept low, and the electroless plating reaction on the upper surface 91 can be suppressed more reliably. As a result, the uniformity of the thickness of the plating layer can be further improved. In addition, it is possible to reduce the amount of new plating solution required to form the solution layer 93a (replacement of the used plating solution and the new plating solution).

Fig. 6 is a diagram showing another example of a plating solution supply part. The plating liquid supply part 3a of FIG. 6 includes a nozzle 31a, a mixing valve 32, a first chemical liquid supply source 33, a second chemical liquid supply source 34, and a cleaning liquid supply source 35. The nozzle 31a is, for example, a straight nozzle, and is arranged above the center portion of the upper surface 91 of the substrate 9. The mixing valve 32 includes a mixing chamber 320, a first valve 321, a second valve 322, a third valve 323, and a fourth valve 324. The first valve 321, the second valve 322, the third valve 323 and the fourth valve 324 are connected to the mixing chamber 320. A first medical solution supply source 33 is connected to the first valve 321 via a first medical solution supply pipe 331, and a second medical solution supply source 34 is connected to the second valve 322 via a second medical solution supply pipe 341. In addition, a cleaning liquid supply source 35 is connected to the third valve 323 via a cleaning liquid supply pipe 351, and a nozzle 31 a is connected to the fourth valve 324. The first chemical liquid supply pipe 331 is provided with a flow rate adjustment valve 332, and the second chemical liquid supply pipe 341 is provided with a flow rate adjustment valve 342.

When the liquid layer of the plating liquid is formed, the first valve 321, the second valve 322, and the fourth valve 324 are opened, whereby the first chemical liquid from the first chemical liquid supply source 33 and the second chemical liquid supply source 34 The second chemical liquid system is mixed in the mixing chamber 320 of the mixing valve 32 and is supplied to the nozzle 31a as a plating liquid. As described above, the first chemical solution system contains the metal salt of the plated metal, and the second chemical solution system contains the reducing agent. The mixing ratio of the first chemical liquid and the second chemical liquid in the plating liquid is adjusted by the flow control valves 332 and 342. It is preferable that the plating solution does not include a stabilizer or a complexing agent, and it is more preferable that the plating solution does not include both a stabilizer and a complexing agent. In addition, when the plating solution on the upper surface 91 is removed by the cleaning liquid, the first valve 321 and the second valve 322 are closed and the third valve 323 and the fourth valve 324 are opened, thereby removing the liquid from the cleaning liquid supply source 35 The cleaning liquid is supplied to the nozzle 31a via the mixing chamber 320.

In the plating solution supply part 3a, since the first chemical solution and the second chemical solution are mixed in the mixing valve 32 connected to the nozzle 31a, it is possible to prevent the first chemical solution supply pipe 331 and the second chemical solution supply pipe 341 from being damaged. The interior is plated. In addition, the plating solution in which the metal salt and the reducing agent have been uniformly mixed can be easily supplied onto the substrate 9. Furthermore, since the plating solution is sprayed from the nozzle 31a immediately after the plating solution is generated, it is also possible to suppress the adverse effects caused by the absence of stabilizers or complexing agents in the plating solution (such as the impact of the plating solution). Deterioration, etc.). When the cleaning liquid is sprayed, the cleaning liquid is a flow path from the mixing position of the first chemical liquid and the second chemical liquid (the mixing chamber 320 in FIG. 6) to the discharge port of the nozzle 31a. Thereby, the plating solution remaining in the flow path can be removed by the cleaning liquid, and the flow path can be prevented from being plated.

Various changes can be made in the electroless plating process and the electroless plating apparatus 1 described above.

In the above embodiment, although the electroless plating reaction in the upper surface 91 is promoted by starting to heat the liquid layer of the plating solution, it is also possible to promote the electroless plating in the upper surface 91 by starting to shake the liquid layer. reaction. For example, a vibrator 43 is provided in the plating reaction promotion part 4a of FIG. 7 instead of the heater 41 of FIG. 1. The vibrator 43 is selectively arranged at an upper position and a lower position by a lifting mechanism not shown. The upper position is a position in contact with the lower surface 92 of the substrate 9, and the lower position is a position separated from the lower surface 92 . In step S16 in the process of FIG. 3, in a state where the spraying of the plating solution from the mixing nozzle 31 toward the upper surface 91 is stopped and the liquid layer 93 of the plating solution is maintained on the upper surface 91, the vibrator 43 is arranged on the upper surface. position. At this time, the rotation of the substrate 9 is stopped. Then, the vibrator 43 starts to be driven, whereby vibration is applied to the substrate 9 to shake the liquid layer 93. Thereby, the plating solution in the solution layer 93 is slowly stirred, and the electroless plating reaction in the upper surface 91 is promoted. In the plating reaction promotion portion 4a, ultrasonic vibration may be applied to the substrate 9.

In addition, it is also possible to rotate the substrate 9 while holding the liquid layer 93 of the plating liquid on the upper surface 91 to thereby shake the liquid layer 93. Furthermore, a vibrator may be added to the heater 41, and both heating of the liquid layer 93 by the heater 41 and shaking of the liquid layer 93 by the vibrator may be performed. As described above, in the electroless plating process, the heating of the liquid layer and/or the shaking of the liquid layer are started in a state where the spray of the plating liquid from the nozzle toward the upper surface 91 is stopped and the liquid layer is maintained on the upper surface 91. This can promote the electroless plating reaction in the upper surface 91. In addition, in the case where the electroless plating reaction is promoted by the rotation of the substrate 9, it is preferable to stop the rotation of the substrate 9 when the liquid layer is formed.

In the electroless plating apparatus 1, it is also possible to use a member for surrounding the outer periphery of the substrate 9 to hold the liquid layer 93 of the plating solution on the upper surface 91. In the electroless plating apparatus 1a of FIG. 8, the substrate holding portion 21a has an annular holding member 214 with the center axis J1 as the center. The diameter of the inner peripheral surface 215 of the holding member 214 increases as it goes upward. That is, the inner peripheral surface 215 is a truncated cone-shaped surface. The diameter in the lower part of the inner peripheral surface 215 is smaller than the outer diameter of the substrate 9, and the diameter in the upper part of the inner peripheral surface 215 is larger than the outer diameter of the substrate 9. A substrate raising and lowering mechanism 216 for raising and lowering the substrate 9 is provided below the holding member 214.

In the electroless plating apparatus 1a, after the substrate 9 is transferred to the substrate elevating mechanism 216 from an external transport mechanism above the holding member 214, the substrate elevating mechanism 216 moves the substrate 9 downward. Thereby, the outer peripheral edge of the substrate 9 is in contact with the inner peripheral surface 215 of the holding member 214 over the entire circumference, and the substrate 9 is held in a horizontal state by the substrate holding portion 21a. In the electroless plating process, the plating solution is sprayed from the mixing nozzle 31 toward the upper surface 91 of the substrate 9. The plating solution is stored in a storage space surrounded by the upper surface 91 of the substrate 9 and the inner peripheral surface 215 of the holding member 214. In other words, the liquid layer 93 of the plating liquid is held on the upper surface 91. After stopping the spraying of the plating liquid from the mixing nozzle 31 toward the upper surface 91, the heater 41a is arranged above the liquid layer 93 by a heater moving mechanism (not shown). Thereby, heating of the liquid layer 93 is started and the electroless plating reaction in the upper surface 91 is promoted.

Through the above-mentioned treatment in the electroless plating apparatus 1a, the uniformity of the thickness of the plating layer can also be improved. In addition, when the plating solution on the upper surface 91 is removed, the substrate lifting mechanism 216 raises the substrate 9, thereby forming a gap between the outer peripheral edge of the substrate 9 and the inner peripheral surface 215 of the holding member 214, and the plating solution It is discharged downward through this gap. A vibrator can also be used in the electroless plating apparatus 1a.

Heating of the liquid layer of the plating solution can also be achieved by various configurations. For example, as shown in FIG. 9, the heater 41 b that has been arranged above the substrate 9 may be moved (scanned) along the upper surface 91 to thereby heat the liquid layer 93 of the plating solution. In addition, heaters using lamps, etc. can also be installed. According to the structure of the heater, the active state and the inactive state of the heating of the liquid layer can be switched by the activation and deactivation of the heater body.

As long as the mixing nozzle 31 and the nozzle 31 a can supply the plating solution to the entire upper surface 91 of the substrate 9, the plating solution may be sprayed toward a position shifted from the center on the upper surface 91.

The formation of the catalyst layer on the upper surface 91 of the substrate 9 is performed by another device. In addition, in the case where a plating layer can be formed on the upper surface 91 without forming a catalyst layer, the supply of the catalyst solution to the upper surface 91 can also be omitted.

Depending on the structure of the plating reaction promoting parts 4, 4a, etc., a substrate holding part for adsorbing and holding the lower surface 92 of the substrate 9 may also be used.

The substrate to be processed in the electroless plating apparatus 1, 1a is not limited to a semiconductor substrate, and may be another substrate.

The configurations in the above-mentioned embodiment and the respective modification examples can be combined appropriately as long as there is no contradiction with each other.

Although the present invention has been described and illustrated in detail, the foregoing description is only illustrative and not restrictive. Therefore, various changes and aspects are possible as long as they do not deviate from the scope of the present invention.

1.1a: Electroless plating device 3.3a: Plating liquid supply part 4. 4a: Plating reaction promotion department 5: Treatment liquid supply part 9: substrate 11: Computer 21, 21a: substrate holding part 22: Substrate rotation mechanism 23: Hood 31: Mixing nozzle 31a: Nozzle 32 mixing valve 33: The first liquid medicine supply source 34: The second source of liquid medicine supply 35: Cleaning fluid supply source 41, 41a, 41b: heater 42: heater lifting mechanism 43: Vibrator 51: auxiliary nozzle 52: Supply source of catalyst solution 53: Detergent supply source 54: Cleaning fluid supply source 81: recording media 91: (of the substrate) upper surface 92: (of the substrate) lower surface 93, 93a: Liquid layer (of plating solution) 94: Plating layer 110: Control Department 111: CPU 112: ROM 113: RAM 114: fixed hard drive 115: Display 116: Input 116a: keyboard 116b: mouse 118: Read and Write Device 119: Ministry of Communications 211: Base 212: Fixture pin 213: Control Department 214: Holding member 215: inner peripheral surface 216: substrate lifting mechanism 221: Shaft 110: Control Department 311, 320: mixing room 312: Ejector 321: first valve 322: second valve 323: The third valve 324: Fourth Valve 331: The first liquid supply pipe 332, 342: flow adjustment valve 333, 343, 353: on-off valve 341: The second liquid supply pipe 351: Cleaning fluid supply pipe 421: Lifting shaft 810: program J1: Central axis

Fig. 1 is a diagram showing the structure of an electroless plating device. Figure 2 is a diagram showing the composition of the computer. Fig. 3 is a diagram showing the flow of electroless plating treatment. Fig. 4A is a diagram for explaining the electroless plating process. Fig. 4B is a diagram for explaining the electroless plating process. Fig. 4C is a diagram for explaining the electroless plating process. Fig. 4D is a diagram for explaining the electroless plating process. Fig. 4E is a diagram for explaining the electroless plating process. Fig. 4F is a diagram for explaining the electroless plating process. Fig. 5A is a diagram for explaining another example of the electroless plating process. Fig. 5B is a diagram for explaining another example of the electroless plating process. Fig. 5C is a diagram for explaining another example of the electroless plating process. Fig. 6 is a diagram showing another example of a plating solution supply part. Fig. 7 is a diagram showing another example of the plating reaction promotion portion. Fig. 8 is a diagram showing another example of the electroless plating device. Fig. 9 is a diagram showing another example of the heater.

1: Electroless plating device

3: Plating solution supply part

4: Plating reaction promotion department

5: Treatment liquid supply part

9: substrate

11: Computer

21: Board holding part

22: Substrate rotation mechanism

23: Hood

31: Mixing nozzle

33: The first liquid medicine supply source

34: The second source of liquid medicine supply

35: Cleaning fluid supply source

41: heater

42: heater lifting mechanism

51: auxiliary nozzle

52: Supply source of catalyst solution

53: Detergent supply source

54: Cleaning fluid supply source

91: (of the substrate) upper surface

92: (of the substrate) lower surface

110: Control Department

211: Base

212: Fixture pin

213: Control Department

221: Shaft

311: mixing room

312: Ejector

331: The first liquid supply pipe

332, 342: flow adjustment valve

333, 343, 353: on-off valve

341: The second liquid supply pipe

351: Cleaning fluid supply pipe

421: Lifting shaft

J1: Central axis

Claims (27)

An electroless plating method comprising: step (a), spraying a plating solution at room temperature from a nozzle toward the upper surface of a horizontal substrate, thereby forming a plating solution covering the entire surface of the upper surface Liquid layer, and by maintaining the liquid layer at room temperature from the beginning of the spraying of the plating solution from the nozzle to the end of the spraying, the reaction of the plating solution is suppressed; and step (b) is stopped from the nozzle toward the After spraying the plating liquid on the upper surface and maintaining the liquid layer on the upper surface, the temperature of the entire lower surface of the substrate is set to a temperature higher than normal temperature to start the heating of the liquid layer. The aforementioned upper surface simultaneously promotes the electroless plating reaction. The electroless plating method as described in claim 1, wherein the plating solution contains a metal salt of the plating metal and a reducing agent for reducing and depositing the ions of the plating metal, and does not contain any usefulness to prevent plating. The stabilizer for the decomposition of the coating liquid may not contain the disintegrating agent. The electroless plating method according to claim 2, wherein in the step (a), immediately before the spraying of the plating solution from the nozzle, the first chemical solution containing the metal salt and the reducing agent are mixed. The second chemical solution of the agent, thereby generating the aforementioned plating solution. The electroless plating method according to claim 1, wherein in the step (a), immediately before spraying the plating solution from the nozzle, the first chemical solution containing the metal salt of the plating metal is mixed with There is a second chemical solution for reducing the precipitated reducing agent of the ions of the plating metal, thereby generating the plating solution. The electroless plating method according to claim 3, wherein the first chemical solution and the second chemical solution are mixed in the nozzle. The electroless plating method according to claim 3, wherein the first chemical solution and the second chemical solution are mixed in a mixing valve connected to the nozzle. The electroless plating method as described in claim 3, which further includes the following Step: After the step (b), spray the cleaning liquid from the nozzle toward the upper surface; before spraying the cleaning liquid, the cleaning liquid passes from the mixing position of the first chemical liquid and the second chemical liquid to the The flow path of the nozzle outlet. The electroless plating method as described in claim 1, which further comprises: step (c), after the step (b), spraying from the nozzle toward the liquid layer of the plating liquid on the upper surface A new plating solution, thereby forming a liquid layer for covering the new plating solution on the upper surface; and step (d) is to stop spraying the new plating solution from the nozzle toward the upper surface and Heating of the liquid layer or shaking of the liquid layer is performed while the liquid layer of the new plating liquid is maintained on the upper surface, thereby promoting the electroless plating reaction on the upper surface. The electroless plating method as described in claim 1, which further includes: step (c), after the step (b), rotating the substrate to remove the liquid layer of the plating solution, and then removing the liquid layer from the plating solution. The nozzle sprays a new plating solution toward the upper surface, thereby forming a liquid layer for covering the new plating solution on the upper surface; and step (d) is to stop spraying the spray from the nozzle toward the upper surface. Heating of the liquid layer or shaking of the liquid layer is performed while maintaining the liquid layer of the new plating liquid on the upper surface, thereby promoting electroless plating on the upper surface reaction. The electroless plating method according to claim 8, which further includes a step for repeating the aforementioned step (c) and the aforementioned step (d). The electroless plating method according to claim 1, wherein in the step (a), the heating of the liquid layer by the heater is set to an inactive state; in the step (b), the heater is The heating of the aforementioned liquid layer is set to an active state. The electroless plating method as described in claim 8, wherein the steps (a) and In the aforementioned step (c), the heating of the liquid layer by the heater is set to an inactive state; in the aforementioned steps (b) and (d), the heating of the liquid layer by the heater is set to an active state . The electroless plating method according to claim 11, wherein the heater faces the lower surface of the substrate, and the upper surface of the heater covers substantially the whole of the lower surface of the substrate; In the state, the heater is arranged at a position close to or in contact with the lower surface; in the inactive state, the heater is arranged at a position separated from the lower surface. The electroless plating method according to any one of claims 1 to 13, wherein in the step (b), the liquid layer of the plating liquid is heated and the state of the liquid layer is maintained on the upper surface Rotate the aforementioned substrate down. The electroless plating method according to any one of claims 1 to 13, wherein in the step (b), the substrate or the substrate is rotated while the liquid layer of the plating liquid is maintained on the upper surface Vibration is given to the aforementioned substrate. An electroless plating device is provided with: a substrate holding part, which holds the substrate in a horizontal state; a plating solution supply part, which sprays a normal-temperature plating solution from a nozzle toward the upper surface of the substrate to form a coating The liquid layer of the plating solution on the entire surface of the upper surface; the plating reaction promoting part is to heat the liquid layer; and the control part is to stop spraying the plating solution from the nozzle to the upper surface and While maintaining the liquid layer on the upper surface, the plating reaction promoting section sets the temperature of the entire lower surface of the substrate to a temperature higher than normal temperature to start heating of the liquid layer, thereby covering the entire surface The upper surface simultaneously promotes the electroless plating reaction. The electroless plating device according to claim 16, wherein the aforementioned plating solution contains There are metal salts of the plated metal and a reducing agent used to reduce and precipitate the ions of the aforementioned plated metal, and it does not contain a stabilizer useful to prevent the decomposition of the plating solution or does not contain a complexing agent. The electroless plating apparatus according to claim 16, wherein the plating solution supply unit mixes the first chemical solution containing the metal salt of the plating metal and the first chemical solution containing the metal salt of the plating metal immediately before spraying the plating solution from the nozzle The second chemical solution of the reducing agent precipitated by the ions of the plating metal is reduced, thereby generating the plating solution. The electroless plating device according to claim 18, wherein after the electroless plating of the liquid layer is used, the plating solution supply unit sprays a cleaning solution from the nozzle toward the upper surface; and the cleaning solution is sprayed In this case, the cleaning liquid passes through the flow path from the mixing position of the first chemical liquid and the second chemical liquid to the ejection port of the nozzle. The electroless plating apparatus according to any one of claims 16 to 19, wherein the plating reaction promotion unit further includes: a heater for heating the liquid layer; when the liquid layer is formed, the The heating of the liquid layer by the heater is set to an inactive state; when the electroless plating reaction is promoted, the heating of the liquid layer by the heater is set to an active state. The electroless plating apparatus according to claim 20, wherein the heater faces the lower surface of the substrate, and the upper surface of the heater covers substantially the entirety of the lower surface of the substrate; In the state, the heater is arranged at a position close to or in contact with the lower surface; in the inactive state, the heater is arranged at a position separated from the lower surface. A program product that enables a computer to be equipped with a substrate holding part and a plating solution supply part And the control of the electroless plating device of the plating reaction promotion part; the computer executes the program displayed by the program product, so that the computer executes: step (a) is directed from the nozzle of the plating solution supply part The upper surface of the substrate held in the horizontal state by the substrate holding portion is sprayed with a plating solution at room temperature, thereby forming a liquid layer of the plating solution covering the entire surface of the upper surface, and by removing the liquid layer from the plating The coating liquid is maintained at room temperature from the start of spraying from the nozzle to the end of the spraying to suppress the reaction of the coating liquid; and step (b) is to stop spraying the coating liquid from the nozzle to the upper surface and on the upper surface While maintaining the liquid layer on the upper surface, the plating reaction promoting section sets the temperature of the entire lower surface of the substrate to a temperature higher than normal temperature to start heating of the liquid layer, thereby covering the upper surface At the same time, it promotes the electroless plating reaction. The program product described in claim 22, wherein the plating solution contains a metal salt of the plating metal and a reducing agent used to reduce and precipitate the ions of the plating metal, and does not contain any usefulness to prevent the plating solution Decomposition stabilizer or does not contain dissolving agent. The program product described in claim 22, wherein in the step (a), immediately before spraying the plating solution from the nozzle, the first chemical solution containing the metal salt of the plating metal is mixed with The ions of the plating metal reduce the deposited second chemical solution of the reducing agent, thereby generating the plating solution. The program product described in claim 24, wherein the following steps are further performed: after the step (b), the cleaning liquid is sprayed from the nozzle toward the upper surface; when the cleaning liquid is sprayed, the cleaning liquid is passed from the The flow path from the mixing position of the first chemical liquid and the second chemical liquid to the ejection port of the nozzle. The program product according to any one of claims 22 to 25, wherein the plating reaction promotion part is further provided with: a heater for heating the liquid layer; in the step (a), the heating The heating setting of the aforementioned liquid layer by the device In the non-actuated state; in the step (b), the heating of the liquid layer by the heater is set to the actuated state. The program product described in claim 26, wherein the heater faces the lower surface of the substrate, and the upper surface of the heater covers substantially the entirety of the lower surface of the substrate; in the actuated state, The heater is arranged at a position close to or in contact with the lower surface; in the inactive state, the heater is arranged at a position separated from the lower surface.

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