JP2002280710A - Method and device for forming conductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device by which a conductor having a high adhesive strength can be formed. SOLUTION: In order to make a seed layer have a high adhesive strength to a substrate W, metallic ions of Cu, etc., are brought into collision with the substrate W with higher energy. Consequently, the adhesive strength of the seed layer can be improved. To be concrete, a bias potential between -70 V and -250 V is given to a foundation layer which is formed on the substrate W, and has a thickness of 100-2,000 Å by brining a hook member 64c composed a movable electrode into contact with the foundation layer and making positive ions, such as Cu<+> , Ar<+> , etc., incident to the foundation layer by accelerating the ions with the bias voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for forming a conductor having good adhesion on the surface of a resin material layer of a wiring board, and more particularly, to a method for forming an interlayer connection in a build-up method multilayer printed wiring board. The present invention relates to a method and an apparatus for forming a conductor.

[0002]

2. Description of the Related Art In recent years, a multilayer printed wiring board of a build-up method has attracted attention as a device capable of meeting the demand for an increase in the degree of integration of a printed wiring board. As a method of forming a conductor constituting this type of build-up printed wiring board, a seed layer is formed on a resin surface by electroless plating, and further, electrolytic plating is performed on the seed layer to form a conductor of the main body. It is common.

[0003]

However, in recent years, with the miniaturization of wiring, the reliability of the plating process has been feared. Specifically, there is a problem of improvement in reliability of connection with the inner layer conductor, reliability of insulation, reduction of adhesion strength, and the like. In particular, in the case of a build-up printed wiring board, if the adhesion of the conductor is insufficient, a defect will occur in a later process or the reliability of the product will be reduced, so securing the adhesion is an important issue.

[0004] Furthermore, as the operation of electronic devices mounted on a printed wiring board has been accelerated, the use of an insulating material having a low dielectric constant has been demanded. There is a need for a new method for forming a conductive layer.

Accordingly, the present invention is directed to a method and an apparatus for forming a conductor for forming a fine wiring having high reliability, and more particularly to a method and an apparatus for forming a conductor having a high adhesion strength to a low dielectric constant material. It is intended to provide a device.

Another object of the present invention is to provide a conductor forming apparatus which can form a highly reliable conductor, is highly efficient, and has a high throughput.

[0007]

According to the present invention, there is provided a method of forming a conductor on a wiring board, comprising the steps of: forming a vaporized particle of a wiring material ionized by plasma on a resin material as an insulator; A first step of depositing and forming a conductive underlayer, and applying ions including evaporating particles of a wiring material ionized by plasma onto the underlayer while applying a predetermined negative voltage to the underlayer. And a second step of causing

[0008] In the above conductor forming method, in the second step, while applying a predetermined negative voltage to the underlayer, high-energy ions including evaporated particles of a wiring material ionized by plasma are formed on the underlayer. Since the light is incident, the adhesive strength of the underlayer to the resin material can be increased. It is not clear why the adhesion strength of the underlayer is increased, but it is possible to obtain a higher adhesion strength by forming a chemical bond between the resin material and the wiring material,
It is conceivable that higher adhesive strength is obtained by the diffusion of the wiring material into the resin material to form a diffusion layer.

In a specific embodiment of the above method, a third step of forming a conductive main body layer by depositing vaporized particles obtained by ionizing a wiring material by plasma on the underlayer after the second step. Is further provided. In this case, the electrical characteristics of the wiring obtained by the body layer having high conductivity can be improved.

[0010] In another specific embodiment of the above method,
The thickness of the underlayer formed in the first step is 100
It is not less than {not more than 2000}. In this case, since the underlayer is appropriately sputtered by the incidence of the high energy ions during the second step, and the high energy ions enter the vicinity of the interface,
The adhesion strength of the underlayer to the resin material can be effectively increased. If the thickness of the underlayer is 100 ° or less, sufficient conduction cannot be ensured, and abnormal discharge may occur on the surface of the underlayer and a good conductive layer may not be obtained. In addition, ionized evaporated particles and the like do not reach the vicinity of the interface between the underlayer and the resin material, and the adhesion strength of the underlayer cannot be increased.

[0011] In another specific embodiment of the above method,
The thickness of the underlayer formed in the first step is 250
{Not less than 500}. In this case, since the underlayer is sputtered more appropriately, the adhesion strength of the underlayer to the resin material can be further increased.

In another specific embodiment of the above method,
The predetermined negative voltage applied to the underlayer in the second step is in a range from −250 V to −70 V with respect to the potential of the vacuum vessel. In this case, since the underlayer is sputtered with appropriate energy, the adhesion strength of the underlayer to the resin material can be effectively increased. If the predetermined negative voltage is -250 V or less, there is a possibility that thermal damage may be formed on the wiring board, and if the predetermined negative voltage is -70 V or more, sufficient evaporation particles and the like of the ionized wiring material on the underlayer can be prevented. Since the light cannot be incident with energy, the adhesion strength cannot be sufficiently improved.

[0013] In another specific embodiment of the above method,
The predetermined negative voltage applied to the underlayer in the second step is -200 V or more to -150 V with respect to the potential of the vacuum vessel.
It is characterized by the following range. In this case, since the underlayer is sputtered with more appropriate energy, the adhesion strength of the underlayer to the resin material can be further increased.

Further, according to the present invention, there is provided an apparatus for forming a conductor, comprising: a plasma source for supplying a plasma beam into a film forming chamber; A hearth having a material evaporation source to be housed, a substrate holding means for holding the wiring board facing the hearth, and a predetermined film thickness made of the film material formed on the wiring substrate held by the substrate holding means Movable electrode means which is detachably connected to the underlayer and applies a predetermined negative voltage to the underlayer.

In the above conductor forming apparatus, the electrode means is detachably connected to an underlayer of a predetermined thickness made of the film material formed on the wiring substrate held by the substrate holding means, and is connected to the underlayer. Since the predetermined negative voltage is applied, ions including evaporated particles of the wiring material ionized by the plasma can be incident on the underlayer in a state where the predetermined negative voltage is applied to the underlayer, and the resin material The adhesion strength of the underlayer to the substrate can be increased.

In a specific aspect of the above-mentioned apparatus, the substrate holding means conveys the wiring board above the hearth, and the electrode means is arranged such that when the wiring board is located immediately above the hearth, Applying the predetermined negative voltage to the wiring board, when the wiring board is located immediately before and after the position directly above the hearth, shuts off the wiring board from a power supply, or applies zero or positive voltage to the wiring board . in this case,
At the same time as the formation of the base layer, the adhesion strength of the base layer can be increased by ionized evaporated particles and the like, and furthermore, the conductive main body layer can be formed on the base layer after processing, so that efficient processing can be achieved. Becomes possible.

In another specific mode of the above-mentioned device,
When the wiring board is located before and after the position immediately above the hearth, the apparatus further includes an inclination holding means for holding the wiring board in an inclined state so as to face the hearth. in this case,
The underlayer and the main body layer can be formed with a relatively uniform film thickness.

In another specific mode of the above-mentioned device,
The apparatus further includes a cooling device for cooling the substrate when the predetermined negative voltage is applied to the wiring substrate by the electrode means. In this case, even if ionized evaporated particles or the like are incident on the underlayer, thermal damage to the wiring substrate is less likely to occur.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIGS.
It is a figure explaining the structure of the conductor formation device concerning a 1st embodiment. 1 is a front view of the apparatus, FIG. 2 is a side view, and FIG. 3 is a plan view. This conductor forming apparatus is an apparatus for forming a conductive layer serving as a seed layer for electrolytic plating on an insulating layer constituting a substrate W for a build-up printed wiring board. , Vacuum vessel 1
A plasma gun 30 for supplying a plasma beam PB into the vacuum chamber 0, an anode member 50 arranged at the bottom of the vacuum vessel 10 and receiving the plasma beam PB, and a substrate W on which a film is to be formed. The apparatus includes a transport mechanism 60 for appropriately moving the substrate W above the loader 50, a loader device 70 for loading the substrate W into the vacuum container 10, and an unloader device 80 for transporting the substrate W from the vacuum container 10.

The vacuum vessel 10 is connected to a gas supply device 21 for supplying an atmospheric gas and an exhaust device 22 for exhausting the atmospheric gas. Gas supply device 21
Can supply an appropriate amount of an atmospheric gas composed of an inert gas such as Ar to the vacuum vessel 10 at an appropriate timing. The atmospheric gas branched from the gas source 21a of the gas supply device 21 is directly introduced into the vacuum vessel 10 via the flow control valve 21b and the flow meter 21c. On the other hand, the exhaust device 22
At this time, the atmospheric gas in the vacuum vessel 10 is appropriately exhausted through the vacuum gate 22b by the exhaust pump 22a. In addition,
The vacuum vessel 10 and the loader device 70 and the unloader device 80 adjacent thereto are partitioned by gate valves 17 and 18 so as to be openable and closable.

The plasma gun 30 is disclosed in Japanese Patent Laid-Open No. 9-1942.
No. 32, etc.
The main body is provided on the side wall of the vacuum vessel 10.
It is mounted on the tubular part 12. This body part is the cathode 3
1 comprises a glass tube 32 one end of which is closed. Moth
In the lath tube 32, a cylinder 3 made of molybdenum Mo is provided.
3 are fixed to the cathode 31 and are arranged concentrically.
LaB inside the cylinder 33 ₆Disk 34 and tongue formed by
And a pipe 35 formed of a barrel Ta.
End of glass tube 32 opposite to cathode 31
And an end of the cylindrical portion 12 provided in the vacuum container 10.
Means that the first and second intermediate electrodes 41 and 42 are concentrically arranged in series.
Is placed. One of the first intermediate electrodes 41 has a plasma
Built-in annular permanent magnet 44 for converging beam PB
Have been. The plasma beam is also provided in the second intermediate electrode 42.
Electromagnetic coil 45 for converging PB is built in
You. In addition, around the cylindrical portion 12, the gas generated on the cathode 31 side is formed.
From the first and second intermediate electrodes 41 and 42
Steering for guiding plasma beam PB into vacuum vessel 10
A coil 47 is provided.

The operation of the plasma gun 30 is controlled by a gun driving device (not shown). This allows
The power supply to the cathode 31 can be turned on / off, the supply voltage to the cathode 31 can be adjusted, and the power supply to the first and second intermediate electrodes 41 and 42, the electromagnet coil 45, and the steering coil 47 can be adjusted. be able to. That is, the intensity and distribution of the plasma beam PB supplied into the vacuum vessel 10 can be controlled.

The pipe 35 disposed at the innermost side of the plasma gun 30 introduces a carrier gas composed of an inert gas such as Ar, which is a source of the plasma beam PB, into the plasma gun 30 and thus into the vacuum vessel 10. It is connected to the above-mentioned gas source 21a via a flow control valve 92b and a flow meter 92c.

The anode member 50 disposed in the lower portion of the vacuum vessel 10 includes a hearth 51 which is a main anode for guiding the plasma beam PB downward, and an annular auxiliary anode 52 disposed therearound.

The former hearth 51 is formed of a conductive material and is supported by a grounded vacuum vessel 10 via an insulator (not shown). The hearth 51 is controlled to an appropriate positive potential by the anode power supply 91, and the plasma beam PB emitted from the plasma gun 30 is
Is sucked down. The hearth 51 has a hearth body 53 as a crucible-shaped material evaporation source in a concave portion at the upper center where electrons in the plasma beam PB from the plasma gun 30 are incident. Inside the hearth body 53, a metal such as copper, which is a film material, is stored in a molten state.

The latter auxiliary anode 52 is constituted by an annular container disposed concentrically around the hearth 51. The annular container accommodates an annular permanent magnet 55 made of ferrite or the like and a coil 56 concentrically laminated therewith. The permanent magnet 55 and the coil 56 are magnetic field control members, and form a cusp-shaped magnetic field immediately above the hearth 51. Thereby, the direction, the plasma density, and the like of the plasma beam PB incident on the hearth 51 can be corrected.

The coil 56 in the auxiliary anode 52 constitutes an electromagnet.
An additional magnetic field is formed so as to be in the same direction as the magnetic field on the center side generated by. That is, by changing the current supplied to the coil 56, the direction of the plasma beam PB incident on the hearth 51 can be finely adjusted.

The container for the auxiliary anode 52 is also made of a conductive material, similarly to the hearth 51. The auxiliary anode 52 is attached to the hearth 51 via an insulator not shown. By changing the voltage applied from the anode power supply 91 to the auxiliary anode 52, the electric field above the hearth 51 can be complementarily controlled. That is, when the potential of the auxiliary anode 52 is made the same as that of the hearth 51, the plasma beam PB is also attracted to the plasma beam PB and the plasma beam PB
Supply is reduced. On the other hand, when the potential of the auxiliary anode 52 is reduced to the same degree as that of the vacuum vessel 10, the plasma beam PB is drawn to the hearth 51 and the hearth body 53 is heated.

The transport mechanism 60 constitutes a substrate holding means,
A roller transfer path 61 composed of a plurality of rollers arranged at equal intervals in the horizontal direction in the transfer space and supporting the end of the substrate W, and moving the substrate W at a constant speed by rotating these rollers at an appropriate speed. And a driving device 62 for driving the motor. Transport mechanism 60
Can be divided into three regions A1 to A3. In the first region A1, an underlayer is preliminarily formed on the substrate W. In the second region A2, ionized evaporated particles are made to enter while a negative bias voltage is applied to the underlayer.
In the third region A3, the main body layer is formed on the underlayer treated with the ionized evaporated particles.

The substrate W carried out of the loader device 70 and transported along the roller transport path 61 to the first area A1 is held by the first substrate tilting device 63 as tilt holding means so as to face the hearth 51. The thin underlayer is formed in the inclined state. The first substrate tilting device 63 includes an electrostatic chuck, and a support plate 63a that suction-holds the substrate W on the roller transport path 61, and a plate driving device that adjusts the tilt of the substrate W by displacing the support plate 63a together with the substrate W. 63b.

Next, the substrate W transported along the roller transport path 61 to the second area A2 is cooled by being held by the power supply cooling device 64, and is cooled by the underlying layer formed by the first substrate tilting device 63. An appropriate negative bias voltage is supplied.
The power supply cooling device 64 includes a cooling plate 64b that receives supply of cooling water or the like from the cooling device 64a and maintains a desired temperature, and a hook member that lifts the substrate W on the roller transport path 61 and urges the cooling plate 64b. A hook driving device 64d for raising and lowering the hook member 64c or displacing the hook member 64c in the horizontal direction and supplying a voltage to the tip of the hook member 64c. Note that the cooling plate 64b is provided with an electrostatic chuck, so that the cooling plate 64b can be held in close contact with the substrate W. Further, the hook member 64c is connected to an appropriate DC power supply as a movable substrate holding means, and can apply an appropriate voltage to the underlayer formed on the surface of the substrate W in the preliminary film formation stage.

Next, the substrate W transported to the third area A3 along the roller transport path 61 is held by a second substrate tilting device 65 as tilt holding means and tilted so as to face the hearth 51, and is tilted. In this state, a relatively thick main body layer is formed on the underlayer. The second substrate tilting device 65 includes an electrostatic chuck, a support plate 65a that suction-holds the substrate W on the roller transport path 61, and a plate driving device that adjusts the tilt of the substrate W by displacing the support plate 65a together with the substrate W. 6
5b.

The loader device 70 is provided in the load lock chamber,
An elevating stage 71 for elevating and lowering a cassette CA containing a plurality of undeposited substrates W to a desired height, and an extruding member 72 for extruding the substrates W in the cassette CA to the roller transport path 61.
And an actuator 73 for moving the pushing member 72 into and out of the cassette CA, and a vacuum pump (not shown) for evacuating the load lock chamber. The operation will be described. When the elevating stage 71 is operated to hold the cassette CA at an appropriate height and the actuator 73 is operated to extend the pushing member 72, the contact member 72a provided at the tip of the pushing member 72 is The substrate W is moved on the roller transporting path 61 in the first area A1 in contact with the edge of W.

The unloader device 80 includes a lift stage 81 for moving a cassette CA accommodating a plurality of substrates W on which films are formed into a load lock chamber and adjusting the cassette CA to a desired height, and a roller W for moving the substrates W in the cassette CA. A gripping member 82 is pulled out from the transport path 61, an actuator 83 for moving the gripping member 82 into and out of the cassette CA, and a vacuum pump (not shown) for evacuating the load lock chamber. In operation, the elevation stage 81 is operated to hold the cassette CA at an appropriate height, the actuator 83 is operated to extend the gripping member 82, and the clip region 83a provided at the tip of the gripping member 82 is used to move the third area. The edge of the substrate W on the roller transport path 61 of A3 is clipped. Next, when the gripping member 82 is contracted by operating the actuator 83, the substrate W can be stored in the cassette CA.

The control device 100 includes a driving device 62 of the transport mechanism 60, plate driving devices 63b and 65b, a hook driving device 64d, and a lifting stage 71 of the loader device 70.
And the operation of the actuator 73, the lifting stage 81 of the unloader device 80, and the actuator 83. Thereby, the cassette CA in the loader device 70 is
The substrate W on which the film is not yet formed is placed on the roller transport path 61 and the first area A1 to the third area A3 are moved to form a base layer in each area, ion irradiation in a negative voltage application state, and main body layer. The formation can take place. The formed substrate W on which the main body layer formation has been completed is transferred from the roller transport path 61 to the unloader device 80.
It is stored in the cassette CA inside.

Hereinafter, the operation of the conductor forming apparatus shown in FIGS. 1 to 3 will be described. First, the cassette CA is loaded into the load lock chamber of the loader device 70, and the load lock chamber is evacuated. From the cassette CA in the loader device 70, the non-film-formed substrates W are sent out one by one by the pushing member 72. The undeposited substrate W sent out from the cassette CA to the roller transport path 61 and moved to the first area A1 is
The first substrate tilting device 63 is attracted to the support plate 63a and held in an inclined state together with the support plate 63a. As a result, the vapor deposition particles from the hearth 51 are incident on the substrate W to which no bias voltage is applied, and 100 °
A relatively thin underlayer of ~ 200 ° is formed. The film forming process will be described in more detail. When a discharge is generated between the cathode 31 of the plasma gun 30 and the hearth 51 in the vacuum vessel 10, a plasma beam PB is generated. The plasma beam PB reaches the hearth 51 while being guided by a magnetic field determined by the steering coil 47 and the permanent magnet 55 in the auxiliary anode 52. The film material such as Cu in the hearth body 53 placed on the hearth 51 is heated by the electric current from the plasma beam PB, and the film material is melted and evaporated, and the particles of the film material are emitted therefrom. These evaporating particles are
It is ionized by the plasma beam PB and adheres to the surface of the substrate W to form a base layer made of a film material such as Cu.
The reason why the substrate W is tilted by the first substrate tilting device 63 is to make the film thickness uniform.

After the substrate W on which the underlayer has been formed is released from being held by the first substrate tilting device 63, the substrate W is transported on the roller transport path 61 to the second area A2. Here, when the pair of hook members 64c is lowered to make the interval between them slightly smaller than the length of the substrate W, and when both hook members 64c are raised, the substrate W is raised and then adsorbed to the cooling plate 64b, and the substrate W is removed. It is cooled to the target temperature. The hook member 64c is connected to a power source, and is connected to the grounded vacuum vessel
A negative bias voltage of about 70 V to -250 V can be applied to the underlayer on the substrate W. As a result, ionized vaporized particles of Cu from the hearth main body 53 are incident on the underlying layer on the substrate W with energy corresponding to the potential of the hook member 64c, so that the underlying layer is gradually thinned by sputtering or lower. The thickness of the formation increases gradually. In such a situation, ionized vapor particles such as Cu or ions of an atmospheric gas such as Ar are incident on the underlayer, so that the adhesion strength of the underlayer to the resin material can be increased. It is considered that the reason why the adhesion strength of the underlayer is increased is that a chemical bond is generated between the resin material of the substrate W main body and the underlayer. Alternatively, it is conceivable that the evaporated particles diffuse into the resin material of the substrate W to form a diffusion layer. When a negative bias voltage is applied to the underlayer on the substrate W, high-energy ions are incident, and the substrate temperature is likely to rise, and there is a concern about damage due to heat. The film is formed while being cooled.

The substrate W, which has been treated with the ionized evaporated particles, is released from the holding by the power supply cooling device 64, and is then transported on the roller transport path 61 to the third area A3. This substrate W is supported by a support plate 65 of a third substrate tilting device 65.
a and is held in an inclined state together with the support plate 65a. As a result, ionized vapor deposition particles from the hearth 51 are incident on the substrate W, and a relatively thick main body layer is formed on the underlayer. The base layer and the main body layer formed in this manner are seed layers required for electrolytic plating in the next step.
Adjust so that the thickness is 0 mm.

The substrate W on which the film formation of the main body layer is completed is loaded into the cassette C by the gripping member 82 provided on the unloader device 80.
A, and the cassette C is determined to have been processed by the unloader device 80 when the processing of one cassette section is completed.
A is taken out.

FIG. 4 is a diagram conceptually illustrating the progress of film formation. FIG. 4A shows an insulating resin layer R on the surface of the substrate W.
6 is a side cross-sectional view showing a stage where an underlayer UL is formed on L. This underlayer UL is formed by the first substrate tilting device 6 shown in FIG.
3 is formed on the substrate W held. FIG. 4 (b)
Is a side sectional view showing a stage in which the underlayer UL formed on the substrate W is modified by applying a negative bias voltage to cause ionized evaporated particles or an atmospheric gas to be incident.
The reforming of the underlayer UL is performed on the substrate W held by the power supply cooling device 64 shown in FIG. FIG. 4C is a side cross-sectional view showing a stage where the main body layer ML is formed on the modified underlayer UL on the surface of the substrate W. The reforming here means
This means that high-energy ions are made incident to improve the adhesion between the substrate and the conductor. The upper body layer ML is formed on the substrate W held by the second substrate tilting device 65 shown in FIG. As described above, the base layer UL and the main body layer ML serve as seed layers for electrolytic plating. This drawing is a conceptual diagram, and the underlayer UL and the main layer ML are not actually separated but are integrated.

Here, specific conditions for forming the underlayer UL and the main body layer ML will be described. When a bias voltage is not applied to the underlayer UL of the substrate W in the conductor forming apparatus shown in FIGS.
The light is incident on the underlayer UL at an energy of 0 eV. But,
With such incident energy, the underlayer UL cannot be sufficiently modified. Therefore, in order to secure a high adhesion strength of the seed layer to the substrate W, metal ions such as Cu are made to collide with the substrate with higher energy.
As a result, it has been experimentally found that the adhesion strength of the seed layer can be improved. Specifically, a hook member 64c, which is a movable electrode, is brought into contact with a base layer UL having a thickness of 100 to 2000 mm formed on the substrate W, and the base layer UL
A bias potential of -70 V to 250 V was applied to L, and positive ions such as Cu ⁺ and Ar ⁺ were accelerated by this bias voltage and incident on the underlayer UL.

At this time, the thickness of the underlayer UL is set to 100 ° to 2000 ° as described above. If the angle is 100 ° or less, sufficient conduction cannot be ensured, and a discharge may occur between the substrate W and the hook member 64c, which is an electrode, and a good film formation may not be performed. I can't.

The bias voltage applied to the underlayer UL is -70 V to -250 V as described above. −70
Above V, the energy of the positive ions incident on the underlayer UL becomes insufficient, and a sufficient adhesion strength cannot be obtained.
When the voltage is −250 V or less, positive ions having high energy enter the substrate W, and various damages including thermal damage are given to the substrate W itself. The lower limit of the bias voltage (−250 V) is an element that depends on the heat resistance of the resin layer forming the substrate W and the cooling efficiency of the substrate W. It can be expected that the underlayer UL can be modified without damaging the substrate W even with a low bias voltage.

Hereinafter, specific experimental examples will be described.
Table 1 shows that when the thickness of the underlayer UL, the bias voltage applied to the underlayer UL, the film formation time under the bias application state, and the thickness of the main body layer ML were changed, the Cu seed layer (underlayer layer) was changed. UL and the body layer ML).

[Table 1]

In Examples 1 to 15, electrolytic plating was performed on the substrate W on which the seed layer was formed as shown in FIGS.
The peel strength was measured in a state where the coating was applied in μm.
In Comparative Example 1, electrolytic plating was performed on a substrate W having an electroless plating layer of about 1000 ° formed on an insulating layer by 20 μm.
In this state, the peel strength was measured.

As is clear from the table, Examples 1 to 15 are shown.
It can be seen that the substrate W on which the seed layer is formed can obtain a considerably higher peel strength than that of the comparative example 1. Further, it can be seen that in the substrate W on which the seed layers of Examples 1 to 11 were formed, a higher peel strength was obtained in each stage than in the case of Examples 12 to 15.

FIG. 5 is a graph of the partial data of Table 1, showing the change in peel strength when the bias voltage is changed while the thickness of the underlayer UL is kept constant. As is clear from the graph, particularly good adhesion strength can be ensured when the bias voltage applied to the underlayer UL is −150 V or less. Note that when the bias voltage is -200 V or lower, the substrate W tends to be thermally damaged, and when the bias voltage is -250 V or lower, the frequency of the thermal damage generated on the substrate W increases.

[Second Embodiment] FIG. 6 is a view showing the structure of a conductor forming apparatus according to a second embodiment. The conductor forming apparatus according to the second embodiment is a modification of the apparatus according to the first embodiment capable of performing single-wafer processing, and is a single-wafer-type conductor forming apparatus that performs a film forming process individually for each substrate W. is there.

In this case, a film formation process is performed while the substrate W is fixed to the cooling plate 164b by the chuck 164f provided on the cooling plate 164b. In order to apply a negative bias voltage to the underlayer on the surface of the substrate W, the movable electrode member 16
4c is provided. The electrode member 164c is driven by an electrode driving device 164d to appropriately displace the tip portion, and a desired negative bias voltage is supplied to the tip portion.

In this apparatus, the substrate W transferred by a transfer robot (not shown) is fixed to the cooling plate 164b, without applying a voltage to the electrode member 164c, and
4 without contacting the electrode member 164c with the substrate W.
An underlayer UL as shown in FIG. Next, the electrode member 164 is fixed while the substrate W is fixed to the cooling plate 164b.
c is brought into contact with the underlying layer UL formed on the substrate W to apply a negative bias voltage to the underlying layer UL, thereby causing ionized evaporated particles to be incident on the underlying layer UL.
The underlayer UL is modified as shown in FIG. Next, while the substrate W is fixed to the cooling plate 164b, the application of the voltage to the electrode member 164c is stopped, and the main body layer ML as shown in FIG. 4C is formed.

Although the present invention has been described with reference to the embodiment, the present invention is not limited to the above embodiment.
For example, the seed layer to be formed on the substrate W is not limited to Cu as long as it is a conductive material.

In FIGS. 1 to 3, the loader device 70 is provided with the pushing member 72 and the actuator 73 to take out the substrate W from the cassette CA. However, it is needless to say that this can be replaced by a transfer robot. Further, the holding member 82 and the actuator 83 of the unloader device 80 can be replaced with a transfer robot. Further, the method of holding the substrate W during film formation is not limited to the illustrated method.

The hook member 64c and the electrode member 164
c is not limited to one that contacts a part of the periphery of the substrate W, and may contact the entire specific side or the entire outer periphery of the substrate W.

Although the above embodiment has been described as an apparatus for forming a conductor of a wiring layer for performing an interlayer connection in a multi-layer printed wiring board of a build-up method, the present invention is not limited to this. It can be applied to films and the like. In addition, high adhesion can be ensured in other similar metallizing processes performed to impart conductivity to the plastic material.

[0055]

As is apparent from the above description, according to the method for forming a conductor according to the present invention, in the second step, while applying a predetermined negative voltage to the underlayer, the conductor layer is formed on the underlayer. ,
Since high-energy ions including evaporated particles of the wiring material ionized by the plasma are made incident, the adhesion strength of the base layer to the resin material can be increased.

Further, according to the conductor forming apparatus of the present invention, the electrode means is detachably attached to the predetermined thickness of the underlayer made of the film material formed on the wiring substrate held by the substrate holding means. Since a predetermined negative voltage is applied to the underlayer while being connected, a high-energy, high-energy layer containing vaporized particles of a wiring material ionized by plasma is formed on the underlayer in a state where a predetermined negative voltage is applied to the underlayer. The ions can be made incident, and the adhesion strength of the base layer to the resin material can be increased.

[Brief description of the drawings]

FIG. 1 is a front view illustrating a conductor forming apparatus according to a first embodiment.

FIG. 2 is a side view of the apparatus of FIG.

FIG. 3 is a plan view of the apparatus of FIG. 1;

FIGS. 4A to 4C are diagrams illustrating a film forming process by the conductor forming apparatus of FIGS. 1 to 3;

FIG. 5 is a diagram for explaining the relationship between the thickness of the underlayer and the peel strength.

FIG. 6 is a diagram illustrating a conductor forming apparatus according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Vacuum container 30 Plasma gun 50 Anode member 51 Hearth 53 Hearth body 60 Transport mechanism 61 Roller transport path 63 First substrate tilting device 64 Power supply cooling device 64b Cooling plate 64c Hook member 64d Hook drive device 65 Second substrate tilting device 65 Third Substrate tilting device 70 Loader device 80 Unloader device W Substrate

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/38 H05K 3/38 B 3/46 3/46 BY F Term (Reference) 4K029 BA08 BB02 BC03 BD02 CA03 CA13 DB03 DB17 DD05 EA01 KA02 KA03 5E343 AA02 AA12 AA39 BB24 BB71 DD24 DD43 ER23 FF16 GG02 5E346 AA12 AA15 AA35 BB01 CC02 CC08 CC32 DD15 DD24 EE33 GG17 HH11

Claims (10)

[Claims] 1. A method for forming a conductor on a wiring board, comprising: a first step of depositing vaporized particles of a wiring material ionized by plasma on a resin material as an insulator to form a conductive underlayer. A second step in which ions including evaporated particles of a wiring material ionized by plasma are incident on the underlayer with a predetermined bias voltage applied to the underlayer. 2. The method according to claim 1, further comprising a third step of depositing vaporized particles obtained by ionizing a wiring material by plasma on the underlayer after the second step to form a conductive main body layer. Item 7. A method for forming a conductor according to Item 1. 3. The method according to claim 1, wherein a thickness of the underlayer formed in the first step is 100 ° or more and 2000 ° or less. . 4. The method for forming a conductor according to claim 1, wherein the thickness of the underlayer formed in the first step is 250 ° or more and 500 ° or less. . 5. The predetermined negative voltage applied to the underlayer in the second step is -250 V with respect to the potential of the vacuum vessel.
The method for forming a conductor according to any one of claims 1 to 4, wherein the voltage is in a range of not less than -70V and not more than -70V. 6. The predetermined negative voltage applied to the underlayer in the second step is -200 V with respect to the potential of the vacuum vessel.
The method for forming a conductor according to claim 1, wherein the voltage is in a range of not less than −150 V and not more than −150 V. 6. 7. A hearth having a plasma source for supplying a plasma beam into a film formation chamber, a hearth arranged in the film formation chamber for guiding the plasma beam and containing a conductive film material; A substrate holding means for holding the wiring substrate in opposition to the hearth, and detachably connected to an underlayer of a predetermined thickness made of the film material formed on the wiring substrate held by the substrate holding means. And a movable electrode means for applying a predetermined negative voltage to the underlayer. 8. The substrate holding means conveys the wiring board above the hearth, and the electrode means applies the predetermined negative voltage to the wiring board when the wiring board is at a position immediately above the hearth. And applying a zero or positive voltage to the wiring substrate when forming the film, when the wiring substrate is located before and after the position immediately above the hearth. Item 8. An apparatus for forming a conductor according to Item 7. 9. The semiconductor device according to claim 1, further comprising: a tilt holding unit that tilts and holds the wiring board so as to face the hearth when the wiring board is located before and after a position immediately above the hearth. An apparatus for forming a conductor according to claim 7. 10. The cooling device according to claim 7, further comprising a cooling device that cools the substrate when the predetermined negative voltage is applied to the wiring substrate by the electrode means. Equipment for forming conductors.