JPH0841626A - Forming device for metallic partial film and its formation - Google Patents

Abstract

PURPOSE:To provide a device for forming a metallic partial film requiring no masking and etching and to provide a method for forming a metallic partial film excellent in moisture resistance using metal easy to be oxidized by using the same device. CONSTITUTION:A device constituted of an ultrafine particle forming chamber 1 provided with a carbon crucible 6 subjected to high-frequency induction heating with a shutter mechanism 9, a film forming chamber 2 in which a conveying tube 3 conveying ultrafine particles, a nozzle 4 and a glass substrate 8 capable of scanning in the (x)-axis direction and (y)-axis direction are arranged, a vacuum pump 15 sucking through the film forming chamber 2, a vacuum pump 16 sucking through the ultrafine particle forming chamber 1 via a suction tube 5 and a gaseous He recycle mechanism 17 provided in the midway of piping returning the exhaust gas from the vacuum pumps 15 and 16 to the bottom part of the ultrafine particle forming chamber 1 is used. The glass substrate 8 is scanned while the Cu ultrafine particles are jetted from the nozzle 4 by the gaseous He having 99.99% purity, and the conveying of the Cu ultrafine particles is made intermittent by the shutter mechanism 9 to form a Cu partial film on the glass substrate 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for forming a metal partial film and a method for forming the metal partial film.
The present invention relates to an apparatus for directly forming a partial film of a metal which is easily oxidized on a substrate without performing masking or etching, and a method for forming the same.

[0002]

2. Description of the Related Art As a method for forming a metal film on a substrate, there are a thick film paste method, a sputtering method, a vacuum deposition method, a plating method and the like. In these methods, in order to form a metal film only in a necessary portion, that is, in order to form a metal partial film, an unnecessary portion on the substrate is shielded (screen), in other words, masking is performed. To form a film, or after forming a film on the entire surface of the substrate, form a resist film at a necessary place and remove the film at an unnecessary place where the resist film was not formed by etching. Is being carried out. Thus, the formation of the metal partial film requires a process such as masking or etching, and the masking material is used for masking, and the resist film is used for etching.

Further, the thick film paste method and the plating method can easily obtain a thick film having a thickness of 1 μm or more by one application, but the sputtering method and the vacuum evaporation method have a small film forming rate, that is, a film forming rate is small. Obtaining a membrane is very time consuming and unsuitable.
In addition, since the plating method uses a water-soluble chemical, it requires a step of washing with water and drying at the end, which requires a large scale of equipment.

Further, when forming a thick film, unoxidized gold and platinum are expensive, and therefore common copper, nickel, etc. are often used, but these easily oxidizable metals are thick film paste method or plating method. When it is formed by (3), oxidation occurs to increase the specific resistance, and a reduction treatment may be required after the film formation. Furthermore, since oxidation of these films also progresses with time and the specific resistance increases, electrical components using these thick metal films have poor reliability and it is difficult to expect a long life.

As another method for forming a thick film, Japanese Patent No. 1531607 by the applicant of the present application, Japanese Patent Application Laid-Open No. 5-2
95525, JP-A-5-295550, JP-A-6-
93430, JP-A-6-101026, JP-A-6-
There is a method of using the gas deposition apparatus disclosed in each of 128728 and Japanese Patent Application No. 5-34184. In either case, ultra-fine particles from evaporated metal vapor can be jetted onto a substrate together with a carrier gas to form a thick film, but in these apparatuses, the carrier gas is not circulated and a metal that is easily oxidized is used. There is no mention of forming a metal film using a.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides an apparatus for directly forming a metal partial film on a substrate without requiring a step such as masking or etching. To aim.

It is another object of the present invention to provide a method for forming a metal partial film which is excellent in moisture resistance and whose specific resistance does not increase with time by using a metal material which is easily oxidized.

[0008]

[Means for Solving the Problems] The above object is to provide an ultrafine particle generation chamber provided with an evaporation source for evaporating a metal, and to arrange the lower end of the ultrafine particle generation chamber directly above the evaporation source. A transport tube for transporting the generated ultra fine particles, a nozzle at the upper end of the transport tube and a nozzle at its tip, and a film forming chamber in which the substrate on which a partial film is to be formed is arranged close to the nozzle, A vacuum pump system for circulating a carrier gas injected together with the ultrafine particles from the ultrafine particle generation chamber to the film formation chamber through the transfer pipe and the nozzle, from the film formation chamber back to the ultrafine particle generation chamber, and A carrier gas recycling mechanism, and a shutter mechanism for intermittently conveying the ultrafine particles in the ultrafine particle generation chamber; and scanning the substrate in the film forming chamber in at least the X-axis direction and the Y-axis direction in the plane thereof. Forming device for a metallic part film, which the scanning mechanism is provided which is achieved by.

Further, the above object is to provide an ultrafine particle generating chamber provided with an evaporation source for evaporating a metal, and an ultrafine particle generating chamber having a lower end located in the ultrafine particle generating chamber and directly above the evaporation source. A transport pipe for transporting the fine particles, a film forming chamber in which the nozzles at the upper end and the tip of the transport pipe are inserted, and the substrate on which the partial film is to be formed is arranged in proximity to the nozzle,
A vacuum pump system for circulating a carrier gas injected together with the ultrafine particles from the ultrafine particle generation chamber to the film formation chamber through the transfer pipe and the nozzle, from the film formation chamber back to the ultrafine particle generation chamber, and A carrier gas recycling mechanism, a shutter mechanism for intermittently conveying the ultra-fine particles in the ultra-fine particle generation chamber, and a scan of the substrate in the film forming chamber in at least the X-axis direction and the Y-axis direction within the plane. In a metal partial film forming apparatus provided with a scanning mechanism, an inert gas having a purity of 99.99% or higher is used as the carrier gas, and the easily oxidizable metal is evaporated from the evaporation source to form ultrafine particles. While generating the particles, the shutter mechanism intermittently conveys the ultrafine particles, and while the substrate is scanned by the scanning mechanism, Method for forming the metal part film, characterized by applying the ultrafine particles to the substrate, is accomplished by.

[0010]

The metal evaporated from the evaporation source in the ultrafine particle generation chamber becomes ultrafine particles, which is carried in the carrier pipe by the carrier gas and jetted from the nozzle to the substrate in the film forming chamber. The shutter mechanism intermittently conveys the ultrafine particles and scans the substrate in at least the X-axis direction and the Y-axis direction in the film forming chamber, so that a metal partial film is formed on the substrate without masking or etching. It

Further, in the formation of the above metal partial film,
By using an inert gas having a purity of 99.99% or higher as a carrier gas to evaporate a metal that is easily oxidized from an evaporation source to form ultrafine particles, a metal having excellent moisture resistance that does not increase specific resistance with time. A partial film is formed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An apparatus and method for forming a metal partial film according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic view showing the entire metal partial film forming apparatus according to the embodiment. The apparatus generally includes an ultrafine particle generation chamber 1, a film formation chamber 2, and a transfer pipe 3 connecting them.
And vacuum pumps 15 and 16 for returning and supplying He (helium) gas in the film formation chamber 2 and the ultrafine particle generation chamber 1 to the bottom of the ultrafine particle generation chamber 1 and a He gas recycling mechanism 17. .

A carbon crucible 6 (inner diameter 5 mmφ, outer diameter 15 mmφ, height 10 mm) is provided as an evaporation source in the ultrafine particle generation chamber 1, and Cu is used as an evaporation material 22.
(Copper) is contained. A coil 7C for induction heating is wound around the carbon crucible 6, and both ends of the coil 7C are provided with a high frequency power source (150 k) provided outside the ultrafine particle generation chamber 1.
Hz) 7. The high frequency induction heating method is adopted for the following reason. That is,
In the resistance heating method, the crucible is heated by Joule heat, and the evaporation material inside is heated by heat transfer from the crucible. Although the molten metal may convect, the viscosity is high, heating may be non-uniform and bumping may occur, and the particle size distribution of the generated ultrafine particles is large. On the other hand, in the high-frequency induction heating method, eddy current is generated in the crucible and the evaporation material to heat the crucible and the evaporation material, so that the heating is uniform and the particle size distribution of the generated ultrafine particles is uniform.

Immediately above the carbon crucible 6 is arranged the lower end of the vertical conveying pipe 3 (inner diameter 1/4 inch).
Above the lower end, a large-diameter suction pipe 5 that shares the axis with the transport pipe 3 is provided. Then, the suction pipe 5 and the transfer pipe 3
The annular space between and is connected to the vacuum pump 16 via the valve 13.
It is connected to the intake side of. This suction pipe 5 is made of carbon
It is provided so as to suck in the ultrafine particles staying in the ultrafine particle generation chamber 1 other than just above the crucible 6. Further, a shutter mechanism 9 is provided to support the bottom of the carbon crucible 6. As shown in FIG. 2A, the shutter mechanism 9 is located at a position where the carbon crucible 6 is directly below the transfer tube 3 and 30 m from this position in the direction indicated by the arrow a.
After moving about m, as shown in FIG.
The crucible 6 is moved between a position immediately below the annular space formed by the suction pipe 5 and a position by a programmed controller (not shown) to open and close the crucible 6. That is, the metal vapor from the carbon crucible 6 is cooled to He gas as a carrier of the atmosphere, and the rising particles 20 as ultrafine particles are sucked into the carrier pipe 3 when A of FIG. The state of being sucked into the suction pipe 5 when closed is shown.
Further, the ultrafine particle generation chamber 1 is provided with a vacuum gauge 1G.

Inside the film forming chamber 2, an upper end of the transfer tube 3 and a nozzle 4 attached to the transfer tube 3 are inserted so as to be close to the tip of the nozzle 4 (variable within a range of 0.1 to 2.0 mm). )
A glass substrate 8 is arranged. The glass substrate 8 is attached to a scannable substrate holder 10, and is 0.01 to 2 mm in the X-axis direction in the horizontal plane of the glass substrate 8 and the Y-axis direction perpendicular thereto by a digital programmable controller (not shown). It is possible to scan at a speed of / sec. Since the carrier tube 3 has a volume, it takes 0.1 seconds to reach the outlet of the nozzle 4 after the ultrafine particles are sucked in. Therefore, even when the scanning of the glass substrate 8 is stopped at a certain point and the shutter mechanism 9 is closed to move to the next point, the ultrafine particles are conveyed by the carrier tube 3.
It is programmed to move to the next point after a certain amount of time elapses from the arrival to the end. That is, the formed metal partial film does not have a tail. Even when the next point is reached and the shutter mechanism 9 is opened, the movement is started after a lapse of time until the ultrafine particles are ejected from the tip of the nozzle 4. A heater unit for heating the glass substrate 8 is built in the substrate holder 10 so that the glass substrate 8 can be kept at a predetermined temperature by a temperature signal from a thermocouple 11 attached to the glass substrate 8. It has become. The film forming chamber 2 is connected to the suction side of a vacuum pump 15 via a valve 14, and the film forming chamber 2 is provided with a vacuum gauge 2G.

The exhaust side pipes of the vacuum pump 15 and the vacuum pump 16 are integrated into one, which is connected to the He gas recycling mechanism 17 through the valve 19, and further, the valve 1
It is connected to the bottom of the ultrafine particle generation chamber 1 via 2 and He gas is fed as a carrier.
Further, the valve 12 has a purity of 99.
A 99% He gas cylinder 18 is connected. In addition,
A branch pipe 20 provided with a valve 20 is provided in the middle of the vacuum pumps 15 and 16 and the valve 19 and adjacent to the valve 19.

The apparatus for forming a metal partial film of this embodiment is constructed as described above. Next, its function, that is, the method for forming a metal partial film will be described.

(Embodiment 1) Referring to FIG. 1, a valve 12,
Open 13, 14, 20 and close valves 19, 21
The entire system including the ultrafine particle generation chamber 1 and the film formation chamber 2 is exhausted to a pressure of 10 ⁻⁴ Pa by vacuum pumps 15 and 16. Next, while continuing the operation of the vacuum pumps 15 and 16, the valve 20 is closed, the valves 19 and 21 are opened, a predetermined amount of He gas having a purity of 99.99% is introduced from the He gas cylinder 18, and the valve 21 is closed. To do. This starts the circulation of He gas as a carrier in the direction indicated by the arrow,
By adjusting the opening of the valve 13, a pressure of 2 kg / cm ² is generated in the ultrafine particle generation chamber 1 and a pressure of about 1 torr is generated in the film forming chamber 2 to generate a differential pressure of about 2 kg / cm ² between the chambers. Let

In this state, the He gas is distributed from the ultrafine particle generation chamber 1 to the carrier pipe 3 at about 10 SLM (standard state liters per minute) and to the suction pipe 5 at about 30 SLM. The reason why the flow rate to the suction pipe 5 is large is that when the ultrafine particles that are not sucked into the transport pipe 3 and stay in the ultrafine particle generation chamber 1 are present, they become agglomerates during the stay, and sometimes the transport pipe 3 This is to prevent the formation of aggregates, since it adversely affects the film that is being formed by being conveyed through the film 3.

After the above condition is established, the carbon crucible 6 is subjected to high frequency induction heating together with the evaporation material 22 contained in advance, that is, Cu to melt and evaporate Cu at about 1500 ° C. Cu vapor is He as a carrier
It collides with gas and is cooled and condensed into ultrafine particles. Most of the generated ultrafine particles of Cu are sucked into the carrier tube 3 together with He gas, and are sprayed from the nozzle 4 onto the glass substrate 8. The glass substrate 8 is preliminarily set to 25 by the heater unit.
It is heated to 0 ° C and C
A u film is formed.

At this time, the Cu film forming rate, that is, the film forming rate is about 10 μm / sec, and the film forming width varies depending on the distance between the nozzle 4 and the glass substrate 8.
It is 0 to 1200 μm. Since the glass substrate 8 can be scanned in the in-plane X-axis direction and Y-axis direction, by combining it with the intermittent transfer of the Cu ultrafine particles by the operation of the shutter mechanism 9, the glass substrate 8 can be scanned from an arbitrary position on the glass substrate 8. It is possible to form a partial film having an arbitrary pattern reaching an arbitrary position. With this method, width 0.8 mm, length 2
A Cu partial film (A) having a thickness of 0 mm and a thickness of 10 μm was formed.

A moisture resistance test was conducted on the Cu partial film (A) obtained above, and the change in resistivity was observed. The results are shown in FIG. Humidity resistance test is temperature 50 ° C, relative humidity 95% R
Conducted under the condition of H, the specific resistance was measured by the four-terminal method. Cu
The specific resistance immediately after formation of the partial film (A) is Cu bulk (pure Cu).
Mass is about 1.7 times, and more than 1000 hours (4
No change was observed in the specific resistance even after a lapse of 0 days or more).

Example 2 A He gas having a purity of 99.99% was used as a carrier in the same manner as in Example 1 except that the evaporation material 22 contained in the carbon crucible 6 was Ni (nickel), and the glass substrate 8 was used. 0.8mm wide, 20mm long,
A Ni partial film having a thickness of 10 μm was formed.

As with Example 1, this Ni partial film was also subjected to a humidity resistance test under the conditions of a temperature of 50 ° C. and a relative humidity of 95% RH, and the results shown in FIG. 4 were obtained. That is, N
The specific resistance immediately after the formation of the i-part film was about 2.6 times that of Ni bulk, and no change was observed in the specific resistance even after 1000 hours or more (40 days or more).

(Comparative Example) Cu was accommodated in the carbon crucible 6 as the evaporation material 22, and the purity was 99.9 as the carrier.
% He gas was used, and four kinds of Cu partial films (B) having different initial specific resistances were formed on the glass substrate 8 in the same manner as in Example 1.
Was formed. Regarding these Cu partial films (B), the temperature is 20 ° C. and the relative humidity is 60% R, which corresponds to general outside air.
The result of the humidity resistance test conducted under the condition of H is shown in FIG.
The specific resistance immediately after the formation of the four kinds of Cu partial films (B) was 30 to 90 times that of Cu bulk, and increased to 60 to 230 times that of Cu bulk in 40 days of the test period, but continued to increase thereafter. .

As is apparent from Example 1 and Comparative Example, the purity of He gas as a carrier is 99.99%.
In the case of (Cu partial film (A) of Example 1) and He gas having a purity of 99.9% (Cu partial film (B) of Comparative Example)
The moisture resistance is extremely different, but such a fact has not been known so far, and it is a phenomenon that is completely unpredictable. Also,
This fact indicates that the purity of H is higher than 99.99% and higher than 100%.
Estimate that e-gas is also effective. In order to confirm this, He gas having a purity of 99.9999% was used, and otherwise the same as in Example 1, except that Cu excellent in moisture resistance was used.
A partial film (C) was obtained.

(Embodiment 3) Sn (tin) and iron-nickel alloy and iron-cobalt alloy are respectively contained as evaporation materials 22 in the carbon crucible 6 and have a purity of 9 as a carrier.
Each partial film was formed in the same manner as in Example 1 using 9.99% He gas.

The tin partial film, the iron-nickel alloy partial film, and the iron-cobalt alloy partial film are all at 50 ° C. and 95%.
In the humidity resistance test for 1000 hours or longer at RH, the specific resistance did not change, showing that it has excellent humidity resistance.

The embodiment of the present invention has been described above.
Of course, the present invention is not limited to these, and various modifications can be made based on the technical idea of the present invention.

For example, in each embodiment, He gas having a purity of 99.99% was used, but Ar (argon) gas or Ne (neon) gas having a purity of 99.99% or more was also used. May be.

Although a single nozzle 4 is adopted in each embodiment, a plurality of multi nozzles may be used.

Further, in each embodiment, the shutter mechanism 9
A method of moving the carbon crucible 6 was adopted as the above, but the transport tube 3 is made flexible, and the lower end portion is bent to displace it from directly above the carbon crucible 6 to close it, and to open it by returning it to the original position. Such a method may be used.

Although the carbon crucible 6 is adopted in each of the embodiments, other materials that can be heated by induction heating,
For example, a crucible of boron nitride may be used.

Although the glass substrate 8 is used in each of the embodiments, other commonly used substrates such as silicon and ceramic substrates may be used.

In each of the embodiments, the carrier pipe 3 and the nozzle 4 are not heated. However, when these are heated to a temperature of about 300 ° C., the deposition of ultrafine particles on the inner wall and the formation of aggregates are suppressed. Therefore, a more preferable metal partial film can be obtained.

In each of the embodiments, one carbon crucible 6 is used, but two crucibles are used to evaporate two different kinds of metals and form a partial film in which two kinds of ultrafine particles to be produced are mixed. It is also possible.

[0038]

As described above, according to the apparatus and method for forming a metal partial film of the present invention, an arbitrary pattern can be formed on an arbitrary portion of the substrate without the need for treatment such as masking or etching. Since the metal partial film can be formed, the cost for forming the metal partial film can be greatly reduced. Further, since an inert gas having a purity of 99.99% or higher is used as a carrier, even if it is a partial film of a metal that is easily oxidized, the specific resistance does not change under high humidity and extremely excellent moisture resistance is exhibited. Therefore, for example, an electric component using a thick film circuit made of a Cu partial film obtained by this method has extremely high reliability. Further, according to the metal partial film forming apparatus and the forming method thereof of the present invention, not only the conductive metal partial film can be formed on the substrate, but also the repair of the electric circuit, the formation of the electrode at any place, Bonding of lead wires or various types of sealing are possible. Furthermore,
This method of forming a metal partial film does not require etching using chemicals and therefore does not pollute the environment.

[Brief description of drawings]

FIG. 1 is a schematic view showing an entire metal partial film forming apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing an operation of a shutter mechanism in the same apparatus, in which A is an open state and B is a closed state.

FIG. 3 is a diagram showing a result of a moisture resistance test on a Cu partial film (A) formed according to Example 1 of the present invention.

FIG. 4 is a diagram showing the results of a moisture resistance test on a Ni partial film formed according to Example 2 of the present invention.

FIG. 5 is a graph showing different initial specific resistances 4 as a comparative example of the present invention.
It is a figure which shows the result of the moisture resistance test about a Cu partial film (B) of a kind.

[Explanation of symbols]

 1 Ultrafine Particle Generation Chamber 2 Film Formation Chamber 3 Conveying Pipe 4 Nozzle 5 Suction Pipe 6 Carbon Crucible 7 High Frequency Power Supply 7C Coil 8 Glass Substrate 9 Shutter Mechanism 15 Vacuum Pump 16 Vacuum Pump 17 He Gas Recycling Mechanism 22 Evaporation Material (oxidized Easy metal)

Claims (7)

[Claims] 1. An ultrafine particle generation chamber provided with an evaporation source for evaporating a metal, and a lower end of the ultrafine particle generation chamber which is arranged immediately above the evaporation source and conveys the generated ultrafine particles. A carrier pipe, a film forming chamber in which a nozzle at an upper end and a tip of the carrier pipe is inserted, and a substrate on which a partial film is to be formed is arranged in proximity to the nozzle, and the carrier pipe from the ultrafine particle generating chamber. A carrier gas recycle mechanism and a vacuum pump system for circulating the carrier gas injected together with the ultrafine particles through the nozzle into the film forming chamber from the film forming chamber to the ultrafine particle generating chamber, A shutter mechanism that intermittently conveys the ultrafine particles is provided in the particle generation chamber, and a scanning mechanism that scans the substrate in at least the X-axis direction and the Y-axis direction in the plane of the film formation chamber. An apparatus for forming a metal partial film, comprising: 2. A suction pipe having a diameter larger than that of the transfer pipe is disposed above the lower end of the transfer pipe in the ultrafine particle generation chamber,
The metal partial film forming apparatus according to claim 1, wherein an annular space between the suction pipe and the transfer pipe is connected to the vacuum pump system. 3. The formation of the metal partial film according to claim 1, wherein the shutter mechanism intermittently conveys the ultrafine particles by shifting back the relative position between the evaporation source and the conveying pipe immediately above the evaporation source. apparatus. 4. An ultrafine particle generation chamber provided with an evaporation source for evaporating a metal, and a lower end of the ultrafine particle generation chamber is provided directly above the evaporation source and conveys the generated ultrafine particles. A carrier pipe, a film forming chamber in which a nozzle at an upper end and a tip of the carrier pipe is inserted, and a substrate on which a partial film is to be formed is arranged in proximity to the nozzle, and the carrier pipe from the ultrafine particle generating chamber. A carrier gas recycle mechanism and a vacuum pump system for circulating the carrier gas injected together with the ultrafine particles through the nozzle into the film forming chamber from the film forming chamber to the ultrafine particle generating chamber, A shutter mechanism that intermittently conveys the ultrafine particles is provided in the particle generation chamber, and a scanning mechanism that scans the substrate in at least the X-axis direction and the Y-axis direction in the plane of the film formation chamber. In the metal partial film forming apparatus, an inert gas having a purity of 99.99% or higher is used as the carrier gas, the easily oxidizable metal is evaporated from the evaporation source to generate ultrafine particles, and the shutter mechanism is used. A method for forming a metal partial film, characterized in that the ultrafine particles are applied onto the substrate from the nozzle while intermittently carrying the ultrafine particles and scanning the substrate by the scanning mechanism. 5. The method for forming a metal partial film according to claim 4, wherein the evaporation source is a crucible containing a metal to be evaporated by high frequency induction heating. 6. The method for forming a metal partial film according to claim 4, wherein the inert gas is helium. 7. The easily oxidizable metal is copper, nickel,
The method for forming a metal partial film according to any one of claims 4 to 6, which is one or more of tin, an iron-nickel compound, and an iron-cobalt compound.