WO2021171551A1

WO2021171551A1 - Object with metal film

Info

Publication number: WO2021171551A1
Application number: PCT/JP2020/008286
Authority: WO
Inventors: 猿渡　哲也; 浩幸上山; 吉岡　尚規
Original assignee: 株式会社島津製作所
Priority date: 2020-02-28
Filing date: 2020-02-28
Publication date: 2021-09-02
Also published as: JPWO2021171551A1; TWI765565B; CN114929926A; TW202146230A

Abstract

An object with a metal film is provided with a substrate containing a resin or a glass, a metal film covering at least part of the substrate, a first layer that is between the substrate and the metal film and contains an oxide of a metal as the major component, the metal being the same as a metal constituting the metal film, and a second layer that is between the substrate and the first layer and contains an oxide of a composition as the major component, the composition being the same as a composition of the substrate. Adhesive strength of the first layer to the second layer is at least 3 N/cm.

Description

Object with metal film

The present invention relates to an object with a metal film.

In order to form a conductive film by metal plating on the surface of an insulator made of an inorganic material such as glass, a thin conductive layer called a seed layer is formed on the surface of the insulator by electroless plating, and this seed layer is used as an electrode for seeding. Electroplating of metal on top of the layer is performed.
As a method of forming a seed layer on the surface of an insulator, it is known that minute irregularities are formed on the surface of the insulator by etching or the like, a catalyst such as palladium is added thereto, and then electroless plating is performed. (Patent Document 1).

Japanese Patent No. 5615881

Conventional objects with metal films are expected to be used in vehicle members such as mirror members, light members, door handle members, and antenna members, and in design products such as notebook PCs and mobile phones (smartphones). There is a problem that the adhesion between the material and the metal film is not sufficient and peeling is likely to occur. Further, it is also expected to be adopted in a circuit part in which a current flows in an electronic circuit, but peeling is an issue.

The object with a metal film according to the first aspect is located between a base material containing resin or glass, a metal film covering at least a part of the base material, and the base material and the metal film, and constitutes the metal film. A first layer containing an oxide of the metal as a main component and a second layer between the base material and the first layer containing the oxide of the composition of the base material as a main component are provided. The adhesion strength of the first layer to the second layer is 3 [N / cm] or more.

According to the present invention, it is possible to realize an object with a metal film having a metal film having high adhesion to a base material such as resin or glass.

FIG. 1 is a diagram illustrating an object with a metal film according to an embodiment. 1 (a) shows a perspective view of an object with a metal film, FIG. 1 (b) shows a cross-sectional view of the object with a metal film, and FIG. 1 (c) shows an enlarged cross-sectional view of the object with a metal film. FIG. 2 is a cross-sectional view of the film forming apparatus. 3A and 3B are views for explaining changes in the metal film before and after the heat treatment, FIG. 3A is a diagram showing the state of the object to be treated and the metal film before the heat treatment, and FIG. 3B is a diagram after the heat treatment. The figure which shows the state of a processing object and a metal film. FIG. 4 is a diagram showing an example of a film forming method. FIG. 5 is a diagram showing a process of forming a plating layer.

(Implementation of an object with a metal film)
Hereinafter, the metal film-attached object 61 of the embodiment will be described with reference to FIG. FIG. 1A is a perspective view of an object 61 with a metal film, and the object 61 with a metal film is, for example, a printed circuit board containing a base material 50 made of flat glass or resin. A metal film 55 as a wiring member is formed on a part of the front surface 50d of the base material 50.

FIG. 1B shows a cross-sectional view of an object 61 with a metal film in a cross section perpendicular to the front surface 50d. On the flat base material 50, not only the metal film 55 is formed on the front surface 50d as described above, but also the metal film 55 is formed on at least a part of the back surface 50e. Further, a through hole 50h penetrating from the front surface 50d to the back surface 50e is formed in a part of the front surface 50d of the base material 50 which is a flat plate, and at least among a part of the through holes 50h. A metal 55h made of the same material as the metal film 55 is formed on the side surface. The metal 55h may be filled in the entire inside of the through hole 50h.

FIG. 1 (c) shows an enlarged cross-sectional view of the metal film-attached object 61 in the vicinity of the front surface 50d of the base material 50 in the region 62 shown by the broken line quadrangle in FIG. 1 (b). On the front surface 50d of the base material 50 of the metal film-attached object 61 of the embodiment, the base material oxide film layer 52, the metal oxide layer 53, and the seed layer 51d are arranged in order from the front surface 50d. A plating layer 54d is formed. The base material oxide film layer 52 is a layer containing an oxide of a component contained in the base material 50 as a main component, and the metal oxide layer 53 is a layer containing a metal oxide contained in the seed layer 51d as a main component. Is.

The seed layer 51d is a conductive layer used when forming the plating layer 54d by electrolytic plating, and is formed by forming a metal such as copper on the front surface 50d by a film forming method such as sputtering.
The plating layer 54d is formed by forming a metal such as copper by electrolytic plating or the like with the seed layer 51d as an electrode.

FIG. 1C shows an enlarged cross-sectional view of the front surface 50d of the base material 50 as an example, but the structure of the back surface 50e of the base material 50 is also upside down, except that the structure is upside down. Is similar to the structure shown in FIG. 1 (c). The seed layer formed on the back surface 50e is referred to as a seed layer 51e as described later, and the plating layer formed on the back surface 50e is referred to as a plating layer 54e as described later.

In the present specification, the seed layer 51d and the seed layer 51e are also referred to as a seed layer 51 together or respectively. Further, the plating layer 54d and the plating layer 54e are also referred to as a plating layer 54 together or respectively.
In the present specification, the seed layer 51 and the plating layer 54 are also referred to as a metal film 55 together or respectively. The metal film 55 is not limited to the one including both the seed layer 51 and the plating layer 54 described above, and the plating layer 54 may be omitted.

In the present specification, the metal oxide layer 53 formed between the base material 50 and the metal film 55 is also referred to as a first layer. Further, the base material oxide film layer 52 formed between the first layer and the base material 50 is also referred to as a second layer.
The seed layer 51 is also formed inside the through hole 50h, and the above-mentioned first layer and second layer are also formed between the inner surface of the through hole 50h of the base material 50 and the seed layer 51. There is.
The metal oxide layer 53 contains, for example, 80% or more of the metal oxide constituting the metal film 55 by weight.

When the base material 50 is glass, the seed layer 51 is copper having a thickness of 300 nm, and the thickness of the second layer (silicon oxide which is the base material oxide film layer 52) is 2.2 nm, the first layer (metal oxide) is used. The measured value of the adhesion strength in the absence of the layer 53 (copper oxide) is 0.1 [N / cm] or less. On the other hand, the measured value of the adhesion strength when the first layer (copper oxide) and the second layer (silicon oxide) are formed between the base material 50 and the seed layer 51 is 3 to 5.5 [. It turned out to improve to N / cm].

That is, in the object with a metal film 61 of the embodiment, the first layer (metal oxide layer 53) and the second layer (base material oxide film layer 52) are formed between the base material 50 and the seed layer 51. As a result, the adhesion strength between the base material 50 and the seed layer 51 is improved to 3 [N / cm] or more. Therefore, the adhesion strength of the first layer 53 to the second layer 52 is also 3 [N / cm] or more. Since the adhesion strength is guaranteed as described above, the metal film 55 can be stably used as the conductive layer or the reflective film.

The thickness of the second layer (base material oxide film layer 52) can be, for example, 2 nm or more and 5 nm or less. When the thickness of the second layer is 2 nm or more and 5 nm or less, the bonding force between the base material 50 and the metal film 55 via the first layer and the second layer can be further enhanced.
The thickness of the first layer (metal oxide layer 53) is, for example, 0.5 nm or more and 5 nm or less. When the thickness of the first layer is 0.5 nm or more and 5 nm or less, the bonding force between the base material 50 and the metal film 55 via the first layer and the second layer can be further enhanced.

The metals contained in the seed layers 51d and 51e and the plating layers 54d and 54e are not limited to the above-mentioned copper, and alloys containing copper, other metals such as nickel, aluminum and chromium, and alloys containing them. It may be. The metal film 55 may be formed only on a part of the base material 50 such as one side, or may be formed over the front surface of the base material 50. The base material 50 does not have to have a through hole 50h formed.
The object 61 with a metal film is not limited to the above-mentioned printed circuit board, and may be, for example, an electronic component having a wiring layer formed on its surface, an optical component, or an ornament, and has an arbitrary shape. And it can be an object of any purpose.

(Film formation equipment)
Hereinafter, a film forming apparatus suitable for manufacturing the object 61 with a metal film of the embodiment will be described with reference to FIG. FIG. 2 is a cross-sectional view showing the film forming apparatus 100.
The film forming apparatus 100 includes a pressure-resistant chamber 1 having a pressure-resistant structure, and inside the pressure-resistant chamber 1, a plasma processing chamber 2, a film-forming processing chamber 3, and a heat treatment chamber 4 separated by

partition walls

5a and 5b are provided. The partition wall 5a is provided with an opening 6a connecting the plasma processing chamber 2 and the film forming processing chamber 3, and the opening 6a can be opened and closed by the opening / closing door 7a. The opening 6a and the opening / closing door 7a form an opening / closing device structure that communicates with and shuts off the plasma processing chamber 2 and the film forming processing chamber 3. The partition wall 5b is provided with an opening 6b connecting the film forming processing chamber 3 and the heat treatment chamber 4, and the opening 6b can be opened and closed by the opening / closing door 7b. The opening 6b and the opening / closing door 7b form an opening / closing device structure that communicates and shuts off the film forming processing chamber 3 and the heat treatment chamber 4.
The film forming apparatus 100 further includes a control device 8.

A plasma generation source 15 is provided in the plasma processing chamber 2. As the plasma generation source 15, a general plasma generation source that generates high-density plasma can be used. The plasma generation source 15 is supplied with electric power from the plasma power supply 19 via the power supply line 20 and is grounded by the ground wiring 21. As the plasma power supply 19, for example, a power source 19 that generates an AC or DC voltage (mainly a negative voltage) having an RF frequency (for example, 13.56 MHz) is adopted.

Hereinafter, the processing target (deposition target) of the film forming apparatus 100 is referred to as a processing target object 50. However, in order to avoid confusion, when the processing object 50 is in the plasma processing chamber 2, it is in the processing object 50a, when it is in the film forming processing chamber 3, it is in the processing object 50b, and in the heat treatment chamber 4. In some cases, the processing target object 50 is referred to as a processing target object 50c, respectively.

On the side of the plasma processing chamber 2 opposite to the plasma generation source 15, a first holding mechanism 23 for holding the processing object 50a of the plasma processing is provided.
Further, a first decompression pump 25a is connected to the plasma processing chamber 2 via a decompression pipe 26, and the inside of the plasma processing chamber 2 is provided by the first decompression pump 25a as a decompression mechanism and the decompression pipe 26. The pressure can be reduced.
The first decompression pump 25a is controlled by the control signal S3 from the control device 8.
The plasma generation source 15 and the first holding mechanism 23 can also be interpreted as a plasma processing unit.

The film forming apparatus 100 reacts with the reaction gas supply pipe 16 connected to the closed space 22 and the reaction gas supply device 17 connected to the reaction gas supply pipe 16 extending outside the pressure resistant chamber 1. A control valve 18 for adjusting the flow rate of the reaction gas supplied from the gas supply device 17 to control the pressure in the closed space 22 is further provided. The adjustment of the opening degree of the control valve 18 is controlled by the control signal S1 from the control device 8. In the example of FIG. 2, the control valve 18 is provided in the reaction gas supply device 17. The reaction gas is supplied to the reaction gas supply device 17 via, for example, a factory pipe 28, but it may be supplied from a gas cylinder.

The film forming processing chamber 3 inside the pressure resistant chamber 1 is provided with a second holding mechanism 35b for holding the object to be processed 50b, and a sputter electrode 33 composed of an electrode portion 31 and a target material 32. As the target material 32, copper is used as an example. As the target material 32, an alloy containing aluminum, another metal, or the above-mentioned metal can also be used. The sputter electrode 33 is connected to a sputter power supply 34.

The sputter power supply 34 can supply 10 kW or more, more preferably 30 kW or more, to the sputter electrode 33. The sputtering power supply 34 is controlled by the control signal S5 from the control device 8.
The sputter electrode 33 and the second holding mechanism 35b can also be interpreted as a film forming portion.
The sputtering electrode 33 or the electrode portion 31 thereof can also be interpreted as a film forming source that supplies a film material to be formed on the object to be processed 50b.

A second decompression pump 25b is connected to the film forming processing chamber 3 via a decompression pipe 37, and the inside of the film forming processing chamber 3 is provided by the second decompression pump 25b as a decompression mechanism and the decompression pipe 37. The pressure can be reduced. The second decompression pump 25b is controlled by the control signal S4 from the control device 8.
The film forming apparatus 100 further includes an inert gas supply pipe 41 for supplying an inert gas such as argon into the film forming processing chamber 3, an inert gas supply device 38 connected to the inert gas supply pipe 41, and the like. It is provided with a control valve 39 that controls the pressure in the film forming processing chamber 3 by adjusting the flow rate of the inert gas supplied from the inert gas supply device 38. In the example of FIG. 2, the control valve 39 is provided on the inert gas supply device 38. The adjustment of the opening degree of the control valve 39 is controlled by the control signal S6 from the control device 8. The inert gas is supplied to the inert gas supply device 38 via, for example, the factory pipe 40, but it may be supplied from a gas cylinder.

In the heat treatment chamber 4 inside the pressure-resistant chamber 1, a third holding mechanism 35c for holding the processing object 50c and a heater 42 for heating and heat-treating the processing object 50c held by the third holding mechanism 35c are provided. It is equipped. As the heater 42, a lamp, a sheathed heater or the like used for so-called annealing treatment can be used.
Electric power is supplied to the heater 42 from the heater power supply 43 arranged outside the pressure-resistant chamber 1. The heater power supply 43 is controlled by the control signal S8 from the control device 8.

A third decompression pump 25c is connected to the heat treatment chamber 4 via a decompression pipe 44, and the inside of the heat treatment chamber 4 can be decompressed by the third decompression pump 25c as a decompression mechanism and the decompression pipe 44. can. The third decompression pump 25c is controlled by the control signal S7 from the control device 8.
The heater 42 and the third holding mechanism 35c can also be interpreted as a heat treatment unit.

The film forming apparatus 100 conveys the processing object 50a for which the plasma processing has been completed from the first holding mechanism 23 in the plasma processing chamber 2 to the second holding mechanism 35b in the film forming processing chamber 3 without being exposed to the atmosphere. It has a first transport mechanism 30a.
Further, in the film forming apparatus 100, the processing object 50b for which the film forming process has been completed is not exposed to the atmosphere from the second holding mechanism 35b in the film forming processing chamber 3, and the third holding mechanism 35c in the heat treatment chamber 4 is not exposed. It has a second transport mechanism 30b for transporting to.

When the film forming process is performed in the film forming apparatus 100, the object to be processed 50a to be filmed is carried into the plasma processing chamber 2 by a carry-in mechanism (not shown) and held by the first holding mechanism 23. The carry-in mechanism (not shown) preferably has a load lock chamber. When the object to be processed 50a is brought in, the opening / closing door 7a between the plasma processing chamber 2 and the film forming processing chamber 3 is closed.

When the control device 8 sends the control signal S3 to the first decompression pump 25a, the pressure inside the plasma processing chamber 2 is reduced, and when the control device 8 sends the control signal S1 to the control valve 18, a predetermined pressure is set in the plasma generation source 15. Reaction gas is supplied. Then, the control device 8 sends the control signal S2 to the plasma power supply 19, so that the plasma generation source 15 is supplied with the plasma power supply 19 via the power supply line 20 for alternating current or direct current of RF frequency (for example, 13.56 MHz). A voltage (mainly a negative voltage) is applied. As a result, an electric discharge is generated in the plasma generation source 15, and the electrons generated by the electric discharge turn the reaction gas into plasma.

The plasma generated by the plasma generation source 15 drifts in the plasma processing chamber 2 from right to left by a distance d in FIG. 2 and reaches the processing object 50a.
Although the plasma is hot at the stage of being emitted from the plasma generation source 15, heat energy is lost due to collision with the reaction gas existing in the plasma processing chamber 2 while drifting in the plasma processing chamber 2, so that the processing target is When the object 50a is reached, the temperature of the plasma has dropped.
Therefore, in the film forming apparatus 100, it is possible to suppress the temperature increase of the processing object 50a during the plasma processing.

In addition, part of the plasma has changed from the plasma (charged state) to the activated state (radical state) due to collision with the reaction gas. Therefore, the object to be treated 50a is exposed not only to the plasma of the reaction gas but also to the reaction gas in the activated state (radical state). In the present specification, the reaction gas in the plasma state and the reaction gas in the activated state (radical state) are referred to as highly reactive reaction gases. Further, activating the surface of the object to be treated 50a by the reaction gas in the plasma state and the reaction gas in the radical state is called plasma treatment.

The plasma treatment activates the surface of the object to be treated 50a and improves the bondability with the metal atom.
The processing object 50a for which the plasma processing has been completed is not exposed to the atmosphere from the first holding mechanism 23 in the plasma processing chamber 2 by the first transport mechanism 30a provided in the plasma processing chamber 2. It is conveyed to the second holding mechanism 35b in 3.

When the object to be processed 50b is held by the second holding mechanism 35b in the film forming processing chamber 3, the control device 8 sends the control signal S5 to the sputtering power supply 34, so that a large amount of electric power is applied to the sputtering electrode 33. .. By this power, the inert gas in the vicinity of the sputtering electrode 33 in the film forming processing chamber 3 is ionized, accelerated by the electric field of the sputtering electrode 33 and collides with the target material 32, and atoms of copper or other metal constituting the target material 32. Is released into the film forming processing chamber 3 and deposited on the object to be processed 50b.
That is, metal atoms are formed on the surface of the object to be treated 50b activated by the above-mentioned plasma treatment without the activated portion being inactivated by water vapor, oxygen, or the like in the atmosphere. Therefore, it is possible to form a metal film having high bondability with the object to be treated, that is, high adhesion.

In a conventional sputtering apparatus, in order to increase the purity of the film to be formed, the pressure inside the sputtering apparatus is generally reduced to about 0.1 Pa to perform the film formation. If the pressure in the sputtering apparatus is higher than this, it is difficult to remove impurities such as water remaining in the sputtering apparatus or released from the object to be treated, and as a result, impurities are mixed in the membrane and the quality of the membrane is improved. This is because it decreases.
However, especially when the object to be treated 50b is a resin, the amount of impurities released from the object to be processed 50b is large and the impurities are continuously released for a long period of time. It is difficult to reduce the pressure to about 1 Pa to form a film.

Therefore, in the film forming apparatus 100, in order to enable film formation of a high-performance film even if the amount of impurities released from the object to be processed 50b is large, the sputtering power source 34 is 10 kW or more with respect to the sputtering electrode 33. More preferably, it is provided with a device capable of inputting a power of 30 kW or more.

When the electric power input to the sputter electrode 33 is large, the amount of metal atoms such as copper emitted from the target material 32 increases and the metal atoms are emitted as compared with the case where a normal electric power of less than 10 kW is input. The kinetic energy of the body also increases. As a result, in the film forming apparatus 100, the concentration of impurities in the film forming processing chamber 3 is relatively reduced with respect to the concentration of metal atoms, so that the purity of the film formed on the object to be processed 50b is improved. .. Further, since the kinetic energy of the metal atom colliding with the processing object 50b is large, the molecules constituting the processing object 50b and the metal atom are stably bonded to each other, so that the film has higher adhesion to the processing object 50b. Can be formed.

The metal atom released from the target material 32 travels straight in the film forming processing chamber 3, but its traveling direction is diffused (scattered) by the collision with the inert gas in the film forming processing chamber 3. However, in the conventional sputtering apparatus, since the kinetic energy of the metal atom is low, the metal atom that collides with the inert gas and scatters and loses the kinetic energy cannot adhere to the object to be processed with sufficient strength. .. For this reason, if the object to be treated has an uneven shape, only metal atoms that are scattered and lose kinetic energy are irradiated on the side surface portion of the uneven shape, so that a uniform film formation is performed on the object to be processed having the uneven shape. It was difficult.

However, in the film forming apparatus 100, since the kinetic energy of the metal atom when it is released from the target material 32 is large, the metal atom has sufficient kinetic energy even after being scattered by the inert gas. Therefore, since the treated object 50b is irradiated with metal atoms having various traveling directions and having a large kinetic energy due to scattering, a uniform film is formed even on the processed object 50b having an uneven shape. It is possible to make a film.

In order to form a uniform film on a processing object having an uneven shape, it is desirable that the pressure in the film forming processing chamber 3 is about 0.5 Pa to 5 Pa. When the pressure is 0.5 Pa or less, it is difficult to sufficiently scatter the metal atoms when released from the target material 32, and when the pressure is about 5 Pa or more, the concentration of impurities in the film forming processing chamber 3 becomes high and the quality of the film becomes poor. It may decrease.

When the object to be processed 50b having less unevenness on the surface is to be processed, the pressure in the film forming processing chamber 3 may be less than 0.5 Pa, and the electric power applied to the sputter electrode 33 may be less than 10 kW.
Further, the film forming source is not limited to the above-mentioned sputtering electrode 33, and may be a vapor deposition apparatus or a CVD apparatus.

The processing object 50b for which the film forming process in the film forming processing chamber 3 has been completed is separated from the second holding mechanism 35b in the film forming processing chamber 3 by the second transport mechanism 30b provided in the film forming processing chamber 3. It is conveyed to the third holding mechanism 35c in the heat treatment chamber 4 without being exposed to the atmosphere. Prior to this transfer, the control device 8 sends a control signal S7 to the third decompression pump 25c to depressurize the inside of the heat treatment chamber 4.

When the object to be processed 50c is held by the third holding mechanism 35c in the heat treatment chamber 4, the control device 8 sends a control signal S8 to the power supply 43 for the heater, so that power is applied to the heater 42 and the object to be processed 50c is processed. Is heated. That is, so-called annealing is performed on the object to be processed 50c.
The heater 42 heats the temperature of the object to be treated 50c to a temperature of 100 ° C. or higher, more preferably about 300 ° C. to 550 ° C. However, it is preferable that the control device 8 and the heater power supply 43 are heated so that the temperature of the object to be treated 50c does not exceed the lowest temperature of its melting point, glass transition or softening point.

In the film forming apparatus 100, the object to be processed 50b formed in the film forming processing chamber 3 can be conveyed to the heat treatment chamber 4 without being exposed to the atmosphere, and the heat treatment (annealing) can be performed in the heat treatment chamber 4 under reduced pressure. .. Therefore, the thin film such as copper or other metal formed in the film forming processing chamber 3 can be annealed while preventing the surface from being oxidized by oxygen in the atmosphere. As a result, the adhesion between the film formed in the film forming processing chamber 3 and the object to be processed 50c can be further improved.

The heat-treated object 50c is carried out from the heat treatment chamber 4 (and the pressure-resistant chamber 1) by a carry-out mechanism (not shown). The carry-out mechanism (not shown) preferably has a load lock chamber.

In the above-mentioned film forming apparatus 100, the plasma processing chamber 2, the film forming processing chamber 3, and the heat treatment chamber 4 are provided in the pressure-resistant chamber 1, but the configuration in the pressure-resistant chamber 1 is limited to this. It is not something that can be done.
For example, the

partition walls

5a and 5b that separate the plasma processing chamber 2, the film forming processing chamber 3, and the heat treatment chamber 4 may be abolished. In this case as well, the plasma generation source 15, the first holding mechanism 23, the sputtering electrode 33, the second holding mechanism 35b, the heater 42, the third holding mechanism 35c, and the like are still arranged in the pressure resistant chamber 1. ..

Alternatively, the plasma processing chamber 2, the film forming processing chamber 3, and the heat treatment chamber 4 can be formed in separate pressure-resistant chambers. However, in this case, a transport path capable of depressurizing or replacing gas with an inert gas is provided between the plasma processing chamber 2 and the film forming processing chamber 3 and between the film forming processing chamber 3 and the heat treatment chamber 4. Is desirable. In this case as well, the objects to be processed 50a and 50b processed in the previous processing chamber can be transported to the next processing chamber without being exposed to the atmosphere. It should be noted that the separate pressure-resistant chambers and the decompression or gas-replaceable transport paths connecting them can be interpreted as one pressure-resistant chamber as a whole.

When the plasma processing chamber 2, the film forming processing chamber 3, and the heat treatment chamber 4 are separated into treatment chambers via

partition walls

5a and 5b or via a transport path, the pressures in the respective treatment chambers are independent. It is preferable in that it can be controlled. As a result, the plasma treatment in the plasma processing chamber 2, the film formation treatment in the film formation processing chamber 3, and the heat treatment in the heat treatment chamber 4 can be performed in parallel, further increasing the processing capacity of the film formation apparatus 100. Can be improved. Further, since the contamination between the plasma processing chamber 2, the film forming processing chamber 3, and the heat treatment chamber 4 can be minimized, the quality of the film to be formed can be further improved.

Further, at least one of the first holding mechanism 23 for holding the processing target object 50a in the plasma processing chamber 2 and the second holding mechanism 35b for holding the processing target object 50b in the film forming processing chamber 3 is the processing target object 50a. , 50b may have a rotation mechanism for rotating the objects to be processed 50a and 50b during the processing so that the processing to 50b becomes uniform.

Further, the first holding mechanism 23 may be provided on the side surface 29 of the plasma processing chamber 2 opposite to the plasma generation source 15.
The mechanism for reducing the pressure in the pressure-resistant chamber 1 is not limited to the above-mentioned first to third pressure reducing pumps 25a to 25c, and for example, low pressure such as vacuum is supplied to the

pressure reducing pipes

26 and 37 via the pressure regulating valve. It may be connected with a power pipe for a factory. In this case, the control device 8 controls the pressure in the plasma processing chamber 2, the film forming processing chamber 3, and the heat treatment chamber 4 by issuing an opening / closing command to the pressure regulating valve.

(Film formation method)
Hereinafter, an example of a film forming method suitable for manufacturing the metal film-attached object 61 of the embodiment (hereinafter, referred to as “first film forming method”) will be described with reference to FIG.
The first film forming method is performed by using the above-mentioned film forming apparatus 100, and includes at least a part of the following steps.

(Bringing in the object to be processed)
The processing object 50a is arranged at a position separated from the above-mentioned plasma generation source 15 installed in the plasma processing chamber 2 in the pressure-resistant chamber 1 by a predetermined distance. At this time, the distance from the plasma generation source 15 to the object to be processed 50a is defined as the distance d.
When the object to be processed 50a is carried into the plasma processing chamber 2, the opening / closing door 7a between the plasma processing chamber 2 and the film forming processing chamber 3 is closed.

(Decompression in the plasma processing chamber)
The inside of the plasma processing chamber 2 is decompressed by the first decompression pump 25a as a decompression mechanism and the decompression pipe 26. At this time, the first decompression pump 25a is controlled by the control signal S3 from the control device 8.
When the plasma processing chamber 2 is provided with a load lock chamber and a carry-in mechanism (not shown) as described above, the decompression in the plasma processing chamber 2 is more than the arrangement of the processing object described above. Will be done before.

(Plasma processing)
The reaction gas is supplied from the reaction gas supply device 17 into the plasma generation source 15 via the reaction gas supply pipe 16, and electric power is applied to the plasma generation source 15 from the plasma power supply 19. As a result, the reaction gas in the plasma state and the reaction gas in the activated state (radical state) are generated from the plasma generation source 15. By exposing the treatment target object 50a to this reaction gas, plasma treatment of the treatment target object 50a is performed.
After the elapse of a predetermined time, the control device 8 stops the supply of the reaction gas into the plasma generation source 15 or reduces the supply amount, stops the application of electric power to the plasma generation source 15, and ends the plasma processing. do.

In the first film forming method, the reaction gas used in the above-mentioned plasma treatment can be oxygen as an example.
As described above, in the plasma treatment method in the first film forming method, the plasma treatment of the object to be treated 50a is performed using not only the reaction gas in the plasma state but also the reaction gas in the activated state (radical state). Has the characteristic of being able to. Therefore, the efficiency of plasma treatment can be further improved by using oxygen having strong reactivity in the radical state as the reaction gas in the plasma treatment method in the first film forming method.
The reaction gas can also be nitrogen.

As an example, as the object to be treated 50a, one containing a resin as a main component can be used.
Since resins generally have low heat resistance, it has been difficult to perform conventional plasma treatment that heats the object to be treated. However, the first film forming method is suitable for use on the processing object 50a containing a resin as a main component because the temperature of the processing object 50a can be prevented by using the above-mentioned film forming apparatus 100.

As an example, the object to be processed 50a containing glass as a main component can be used.
Glass is generally vulnerable to sudden temperature changes, making it difficult to perform conventional plasma treatment. However, since the first film forming method can prevent the temperature of the object to be processed 50a from becoming high by using the above-mentioned film forming apparatus 100, it is suitable to be used for the object to be processed 50a containing glass as a main component.

(Transportation of objects to be processed)
The plasma-treated processing object 50a is transported from the plasma processing chamber 2 to the film-forming processing chamber 3 by the first transport mechanism 30a. The opening / closing door 7a between the plasma processing chamber 2 and the film forming processing chamber 3 is opened prior to the transportation, and the opening / closing door 7a is closed after the transportation.
The object to be processed 50a is held by the second holding mechanism 35b in the film forming processing chamber 3. The processing object 50a that has been conveyed and held by the second holding mechanism 35b in the film forming processing chamber 3 is referred to as a processing object 50b.

(Film film processing)
By supplying the inert gas from the inert gas supply device 38 to the film forming processing chamber 3 via the inert gas supply pipe 41 and supplying power from the sputtering power supply 34 to the sputtering electrode 33, the object to be processed A film formation (sputtering) is performed on 50b.
At the time of sputtering, it is preferable that power of 10 kW or more, more preferably 30 kW or more is supplied from the sputtering power supply 34 to the sputtering electrode 33. As a result, the amount of metal atoms such as copper emitted from the target material 32 can be increased and the kinetic energy of the metal atoms can be increased as compared with the case where a normal electric power (several kW) is applied. As a result, as described above, a film having high purity and high adhesion to the object to be treated 50b can be formed.

Further, it is preferable that the pressure in the film forming processing chamber 3 at the time of film forming (sputtering) processing is about 0.5 Pa to 5 Pa. In the conventional sputtering process, if the film is formed under such a low vacuum, impurities may be mixed in the film and the quality of the film may be deteriorated. Further, when the object to be treated 50b is a resin, it is difficult to reduce the pressure at the time of film formation to about 0.5 Pa or less due to the outgas from the object to be treated 50b.

However, by applying a large power of 10 kW or more to the sputter electrode 33, impurities are prevented from being mixed into the film as described above, so that the purity is high and the object to be treated is high even under a pressure of about 0.5 Pa to 5 Pa. A film having high adhesion to the object 50b can be formed.
Further, by setting the pressure in the film forming processing chamber 3 at the time of film forming (sputtering) processing to about 0.5 Pa to 5 Pa, a uniform film can be obtained even with respect to the object to be processed 50b having an uneven shape as described above. A film can be formed.

When the surface of the object to be processed 50b has few irregularities, the pressure in the film forming processing chamber 3 may be set to less than 0.5 Pa, and the power applied to the sputtering electrode 33 may be set to less than 10 kW for sputtering.
Further, the film formation is not limited to sputtering, but can also be performed by using vapor deposition, CVD, or the like. However, in sputtering, as compared with other film forming methods, atoms constituting the film collide with the object to be treated 50b with higher energy, which is preferable in that a film having better adhesion can be formed.

(Transportation of objects to be processed)
The object to be processed 50b formed in the film forming processing chamber 3 is conveyed from the film forming processing chamber 3 to the heat treatment chamber 4 by the second conveying mechanism 30b. The opening / closing door 7b between the film forming processing chamber 3 and the heat treatment chamber 4 is opened prior to the transportation, and the opening / closing door 7b is closed after the transportation.
The object to be treated 50b is held by the third holding mechanism 35c in the heat treatment chamber 4. The object to be processed 50b that has been conveyed and held by the third holding mechanism 35c in the heat treatment chamber 4 is referred to as an object to be processed 50c.

(Heat treatment)
When the object to be processed 50c is held by the third holding mechanism 35c in the heat treatment chamber 4, the control device 8 sends a control signal S8 to the power supply 43 for the heater, so that power is applied to the heater 42 and the object to be processed 50c is processed. Is heated. That is, heat treatment, so-called annealing, is performed on the object to be treated 50c.

The temperature of the object to be treated 50c is preferably 100 ° C. or higher, more preferably 300 ° C. to 550 ° C. or higher. However, it is preferable to heat the object to be treated so that the temperature of the object to be treated does not exceed the lowest temperature of its melting point, glass transition or softening point.
If the heating temperature is lower than 100 ° C., a sufficient annealing effect cannot be obtained, and if the temperature exceeds the lowest of the melting point, glass transition or softening point of the object to be treated 50c, the object to be treated 50c may be deformed.

The heating time of the object to be treated 50c is 1 minute or more, more preferably 3 minutes or more, and in order to shorten the treatment time (improve productivity), it is preferably 1 hour or less, more preferably 20 minutes or less. good.
If the heating time is less than 1 minute, a sufficient annealing effect cannot be obtained, and if the heating time exceeds 1 hour, the productivity may decrease.

FIG. 3 is a diagram illustrating changes in the metal film 55 formed in the above-mentioned film forming step before and after the heat treatment, and FIG. 3 (a) is formed on the front surface 50d of the object to be treated 50. FIG. 3B is a partially enlarged view showing the state of the metal film 55 before the heat treatment and showing the state after the heat treatment.

Before the heat treatment shown in FIG. 3A, between the object to be treated 50 and the metal film 55, a deformed product in which the composition of the object to be treated 50 has undergone alteration such as oxidation by the above-mentioned plasma treatment is contained. The base material oxide film layer 52a is formed. The deformed product that has undergone alteration such as oxidation by plasma treatment is, for example, an oxide of the composition of the treatment target 50 in the case of treatment with oxygen plasma, and the composition of the treatment target 50 in the case of treatment with nitrogen plasma. It is a nitride of things. In addition, a part of the molecular structure (for example, a functional group) constituting the composition of the object to be treated 50, which is partially cleaved by the plasma treatment, is also included.

From this state, when the object to be treated 50 on which the metal film 55 is formed is heat-treated (annealed), oxygen or nitrogen contained in the base material oxide film layer 52a reacts with the metal atoms in the metal film 55 by heat. do. As a result, a metal oxide layer (or metal nitride layer) 53 containing the metal oxide or nitride constituting the metal film 55 as a main component is formed between the base material oxide film layer 52a and the metal film 55. NS.

In the first film forming method, the object to be processed 50b formed in the film forming processing chamber 3 is conveyed to the heat treatment chamber 4 without being exposed to the atmosphere, and the heat treatment chamber 4 is subjected to heat treatment (annealing) under reduced pressure. Therefore, the thin film such as copper or other metal formed in the film forming processing chamber 3 can be annealed while preventing the surface from being oxidized by oxygen in the atmosphere. As a result, the adhesion between the film formed in the film forming processing chamber 3 and the object to be processed 50c can be further improved.

The thickness T53 of the metal oxide layer 53 (first layer) changes depending on the temperature and time of the heat treatment (annealing). Therefore, the temperature and time of the heat treatment (annealing) can be set so that the thickness of the first layer becomes an appropriate thickness.
As described in the above-described embodiment of the metal film-attached object, when the thickness T52 of the base material oxide film layer 52 (second layer) is 2 nm or more and 5 nm or less, the first layer (metal oxide layer 53) And the bonding force between the base material 50 and the metal film 55 via the second layer can be further enhanced. Further, when the thickness T53 of the metal oxide layer 53 (first layer) is 0.5 nm or more and 5 nm or less, the base material 50 and the metal film 55 pass through the first layer and the second layer. The bonding force can be further increased.

Since a part of oxygen or nitrogen contained in the base material oxide film layer 52a is lost from the base material oxide film layer 52a by reacting with the metal atoms in the metal film 55, the base material oxide film layer after heat treatment is used. The thickness T52 of 52 is smaller than the thickness of the base material oxide film layer 52a before the heat treatment.

The heat-treated object 50c is carried out from the heat treatment chamber 4 (and the pressure-resistant chamber 1) by a carry-out mechanism (not shown). When the object to be processed 50c is carried out, the opening / closing door 7b between the film forming processing chamber 3 and the heat treatment chamber 4 is closed.

In the above embodiment, the plasma treatment, the film formation treatment, and the heat treatment are performed in the plasma treatment chamber 2, the film formation treatment chamber 3, and the heat treatment chamber 4, which are both partitioned by the

partition walls

5a and 5b in the pressure resistant chamber 1, respectively. However, the place where each process is performed is not limited to this.
For example, plasma treatment, film formation treatment, and heat treatment may be performed in the pressure resistant chamber 1 without

partition walls

5a and 5b.
Alternatively, each process can be performed in a separate pressure resistant chamber. However, in this case, the space between the plasma processing chamber 2 and the film forming processing chamber 3 and the film forming processing chamber 3 and the heat treatment chamber 4 pass through a transport path capable of decompression or gas replacement with an inert gas. It is desirable to carry it out. In this case as well, the objects to be processed 50a and 50b processed in the previous processing chamber can be transported to the next processing chamber without being exposed to the atmosphere.

Further, the first to

third holding mechanisms

23, 35b, 35c for holding the objects to be processed 50a to 50c are provided with a rotation function for rotating the objects to be processed 50a to 50c, so that the objects to be processed 50a to 50c can be uniformly processed. Therefore, the objects to be processed 50a to 50b may be rotated during the processing.
The above processing procedure can be performed by executing a program stored in the control device 8 in advance. Alternatively, a sequence circuit may be mounted on the control device 8.

(Another film formation method)
Hereinafter, another example of a film forming method suitable for manufacturing the metal film-attached object 61 of the embodiment (hereinafter, referred to as “second film forming method”) will be described with reference to FIGS. 2 to 5. However, since most of the second film forming method is common to the first film forming method described above, only the differences from the film forming method of the embodiment will be described below.
In the second film forming method, the object to be treated 50 is, for example, a substrate made of a material containing resin or glass, and a plurality of through holes 50h connecting the front surface 50d and the back surface 50e are formed. ..

FIG. 4A shows a state in which the plasma treatment described in the first film forming method described above is performed on the front surface 50d of the object 50 to be processed in the second film forming method. The plasma treatment with the oxygen radical O * is performed in the plasma treatment chamber 2 of the film forming apparatus 100 shown in FIG.
Next, the object to be processed 50 is inverted, and the back surface 50e is plasma-treated as shown in FIG. 4 (b). The oxygen radical O * is irradiated not only on the front surface 50d and the back surface 50e of the object to be treated 50 but also on the inner surface of the through hole 50h to activate these portions.

After that, the object to be processed 50 is moved from the plasma processing chamber 2 of the film forming apparatus 100 shown in FIG. 2 to the film forming processing chamber 3, and as shown in FIG. 4 (c), with respect to the front surface 50d. A metal such as copper (Cu) is formed by sputtering. In the sputtering of the above-described embodiment, since the object to be processed 50 has various traveling directions due to scattering and is irradiated with copper atoms having a large kinetic energy, the inner surface of the through hole 50h is also highly adhered to. A metal can be formed with the property.

Next, the object to be treated 50 is inverted, and as shown in FIG. 4D, a metal is formed on the inner side surfaces of the back surface 50e and the through hole 50h.
The processing order of the front surface 50d and the back surface 50e in the plasma treatment and the film forming treatment may be reversed from the above-mentioned order.

Through the above steps, as shown in FIG. 4E, seed layers 51d and 51e, which are metal films, are formed on the front surface 50d, the back surface 50e, and the inner surface of the through hole 50h of the object to be treated 50. NS. The processed object 50 on which the seed layers 51d and 51e shown in FIG. 4 (e) are formed is referred to as a processed object 60 with a seed layer.

The thickness of the seed layer 51 is, for example, about 100 nm to 500 nm. The diameter of the through hole 50h is 20 μm to 50 μm on the front surface 50d and the

back surface

50e, and 15 μm to 20 μm on the intermediate portion between the front surface 50d and the back surface 50e. That is, the inner diameter may be large in the vicinity of the front surface 50d and the back surface 50e, and the inner diameter may be relatively small inside.

After that, the object to be treated 50 (the object to be treated with the seed layer shown in FIG. 4E) is not exposed to the atmosphere from the film forming processing chamber 3 of the film forming apparatus 100 shown in FIG. 2 to the heat treatment chamber 4. It is moved and heat-treated (annealed) under reduced pressure. The heat treatment is performed under the conditions (temperature, time) shown in the first film forming method described above.

The seed layer 51 formed on the front surface 50d and the back surface 50e of the object to be processed 50 in the above steps can be selectively removed by photolithography to form a seed layer 51 having a predetermined pattern shape. can.
Alternatively, by masking a part of the front surface (front surface 50d, back surface 50e) of the object to be treated 50 prior to the above-mentioned plasma treatment, the seed layer 51 is not formed in the masked portion, and other than that. The seed layer 51 can also be formed on the surface of the surface.

The material of the seed layers 51d and 51e to be formed is not limited to copper, and may be an alloy containing copper, other metals such as aluminum, chromium, and nickel, and alloys containing them.

The object 60 with a seed layer that has been heat-treated is subjected to electrolytic plating using the seed layer 51 as an electrode to form a plating layer 54 on the seed layer 51.
FIG. 5 is a diagram showing this electrolytic plating process, in which the object 60 to be treated with the seed layer is immersed in the electrolytic solution 46 of the electrolytic plating apparatus 45, and the surface of the seed layer 51 is connected to the power supply 47. The lead wire 49a is connected. A counter electrode 48 is installed in the electrolytic solution 46, and a conducting wire 49b connected to the power supply 47 is connected to the counter electrode 48.

The electrolytic solution 46 contains copper ions as an example, and by applying a potential lower than that of the conductor 49b to the conductor 49a by a predetermined potential difference, copper is deposited on the surface of the seed layer 51 of the object 60 to be treated with the seed layer. Electroplating is performed. As the counter electrode 48, a copper plate is used as an example. Since the electrolytic solution 46 also permeates the inside of the through hole 50h and the seed layer 51 is formed on the inner surface of the through hole 50h, copper is also plated inside the through hole 50h.
Also in the electrolytic plating step, the surface of the seed layer 51 can be partially plated by masking a part of the surface of the seed layer 51 in advance.

By completing the electroplating process, the printed circuit board shown in FIG. 1 is completed as an example of the object 61 with a metal film.
The above-mentioned plating step is not limited to the above-mentioned electroplating, and may be performed by electroless plating or in combination with electroless plating and electroless plating.

Further, if a sufficiently low electric resistance value can be obtained with the seed layer 51 alone, the plating step may be omitted.
Alternatively, the plating step in the second film forming method may be applied to the above-mentioned first film forming method. That is, in the first film forming method described above, the plating step may be performed on the object 50 to be processed after the heat treatment described above.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Moreover, each embodiment and modification may be applied individually or may be used in combination. Other aspects conceivable within the scope of the technical idea of the present invention are also included within the scope of the present invention.

(Aspect)
It will be understood by those skilled in the art that the plurality of exemplary embodiments described above are specific examples of the following embodiments.

(Item 1) The object with a metal film according to one embodiment is located between a base material containing resin or glass, a metal film covering at least a part of the base material, and the base material and the metal film, and is described above. A first layer containing a metal oxide as a main component constituting a metal film, and a second layer between the base material and the first layer containing an oxide of the composition of the base material as a main component. , And the adhesion strength of the first layer to the second layer is 3 [N / cm] or more.
With this configuration, the adhesion of the metal film 55 to the base material (object to be treated) 50 is enhanced, and a tough metal film 55 that is difficult to peel off can be realized.

(Item 2) The object with a metal film according to another aspect is the object with a metal film according to the first item, wherein the thickness of the second layer is 2 nm or more and 5 nm or less. As a result, the adhesion of the metal film 55 to the base material 50 via the first layer and the second layer can be further enhanced.

(Item 3) The object with a metal film according to another aspect is the object with a metal film according to the first item, wherein the thickness of the first layer is 0.5 nm or more and 5 nm or less. As a result, the adhesion of the metal film 55 to the base material 50 via the first layer and the second layer can be further enhanced.

(Item 4) The object with a metal film according to another aspect is the object with a metal film according to the first item, wherein the thickness of the second layer is 2 nm or more and 5 nm or less, and the first item is described. The thickness of the layer is 0.5 nm or more and 5 nm or less. As a result, the adhesion of the metal film 55 to the base material 50 via the first layer and the second layer can be further enhanced.

(Item 5) The object with a metal film according to another aspect is the object with a metal film according to any one of items 1 to 4, wherein the base material is a flat plate having a through hole. The metal film, the first layer, and the second layer are provided on at least a part of the inner surface of the through hole. As a result, an object 61 with a metal film, which is a printed circuit board and in which wiring (metal 55h) having high peel resistance due to a conductor is formed between the front surface 50d and the back surface 50e of the flat plate (base material 50). Can be realized.

(Section 6) The object with a metal film according to another aspect is the object with a metal film according to the fifth aspect, wherein the main component of the metal film is copper. As a result, it is possible to realize an object with a metal film, which is a printed circuit board having low electrical resistance.

(Section 7) The object with a metal film according to another aspect is the object with a metal film according to any one of items 1 to 4, wherein the adhesion strength of the metal film to the base material is high. 3, [N / cm] or more. Therefore, it is possible to realize an object with a metal film having a metal film having high peel resistance.

61: Object with metal film, 50, 50a to 50d: Base material (object to be treated), 51, 51d, 51e: Seed layer, 52: Base material oxide film layer (second layer), 53: Metal oxide layer ( 1st layer), 54, 54d, 54e: metal plating layer, 55: metal film, 100: film forming apparatus, 1: pressure resistant chamber, 2: plasma processing room, 3: film forming processing room, 4: heat treatment room, 8 : Control device, 15: Plasma source, 16: Reaction gas supply pipe, 17: Reaction gas supply device, 18: Control valve, 19: Plasma power supply, 23: First holding mechanism, 25a: First pressure reducing pump, 25b : 2nd decompression pump, 25c: 3rd decompression pump, 33: Sputter electrode, 34: Spatter power supply, 35b: 2nd holding mechanism, 35c: 3rd holding mechanism

Claims

With a substrate containing resin or glass,
A metal film covering at least a part of the base material and
A first layer between the base material and the metal film, which is mainly composed of an oxide of a metal constituting the metal film,
A second layer, which is between the base material and the first layer and contains an oxide of the composition of the base material as a main component, is provided.
An object with a metal film having an adhesion strength of the first layer to the second layer of 3 [N / cm] or more.
In the object with a metal film according to claim 1,
An object with a metal film having a thickness of 2 nm or more and 5 nm or less in the second layer.
In the object with a metal film according to claim 1,
An object with a metal film having a thickness of the first layer of 0.5 nm or more and 5 nm or less.
In the object with a metal film according to claim 1,
The thickness of the second layer is 2 nm or more and 5 nm or less.
An object with a metal film having a thickness of the first layer of 0.5 nm or more and 5 nm or less.
In the object with a metal film according to any one of claims 1 to 4.
The base material is a flat plate having through holes, and is
An object with a metal film, wherein the metal film, the first layer, and the second layer are provided on at least a part of the inner surface of the through hole.
In the object with a metal film according to claim 5.
An object with a metal film in which the main component of the metal film is copper.
In the object with a metal film according to any one of claims 1 to 4.
An object with a metal film having a metal film adhesion strength to the base material of 3 [N / cm] or more.