JP3141166B2 - Method of forming film by gas devolution method and apparatus for forming film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a film by a gas devolution method and an apparatus for forming the film, and more particularly to a method for forming a film such as spot-shaped or line-shaped patterning and an apparatus for forming the film. .

[0002]

2. Description of the Related Art Conventionally, as a method of forming this kind of film, for example, a supply part b of particles a of a film material and a film forming apparatus c as shown in FIG. After introducing a carrier gas (for example, an inert gas such as helium gas) from the introduction pipe d to bring the inside of the supply section b into a predetermined pressurized state,
For example, a film material e such as Ag is heated by an evaporation source f to generate the particles a, and the particles a are suspended in a carrier gas in a supply part b. Then, the particles a together with the carrier gas are jetted from the nozzle h connected to the tip side of the conveying pipe g onto the substrate i in the film forming apparatus c to deposit and form an Ag film. In addition, the start or stop of the transfer of the particles a together with the carrier gas from the supply section b to the film forming apparatus c can be started or stopped by a valve j connected to the gas introduction pipe d or an openable shutter k arranged in the middle of the transfer pipe g (for example, The opening and closing operation of a ball valve (indicated by a virtual line in FIG. 5) is performed. In the figure, m denotes a vacuum pump connected via an exhaust pipe o provided with a valve n, and p denotes a substrate holding device for holding and moving the substrate g in the horizontal direction.

[0003]

However, in the above-mentioned conventional film forming method, the start or stop of the transfer of the particles a from the supply section b to the film forming apparatus c is determined by the valve j connected to the gas introduction pipe d or the transfer. Shutter k to be placed in the middle of tube g
When the valve j or the shutter k is closed, the pressure difference in the transport pipe g disappears, and as a result, the particles a during transport are settled down in the transport pipe g as sediment.
After that, when the valve j or the shutter k is opened again and the conveyance is resumed, the sediment in the conveyance pipe g becomes an aggregate and adheres to the inside of the shutter k when the shutter is provided in the conveyance pipe g or the conveyance pipe. Or is sprayed from the nozzle h and deposited on the substrate i to form a film having an uneven thickness, or an unnecessary film is formed on the substrate i, or the film is skirted. There is a problem.

[0004] The present invention provides a gas
An object of the present invention is to provide a method for forming a film by a devotion method and a forming apparatus suitable for performing the method.

[0005]

SUMMARY OF THE INVENTION The present invention proposes a method for forming a film which achieves the above-mentioned object. The present invention proposes a method for forming a film, in which particles of a film material are transported together with a carrier gas by a transport tube, and are ejected from a nozzle onto a substrate. In the film formation method by gas devotion method to form the film, after stopping the transportation of the particles by closing the shutter that can be opened and closed, the particles and the carrier gas are circulated upstream from the shutter into a transportation pipe different from the transportation pipe. In addition, a gas is introduced into the transport pipe downstream of the shutter. Furthermore, the present invention proposes a forming apparatus for carrying out the above forming method, wherein a gas comprising a transfer pipe for transferring particles together with a carrier gas, a substrate, and a nozzle for spraying particles together with the gas onto the substrate. In the film forming apparatus by the devotion method, an openable and closable shutter is arranged in a part of the transfer pipe, a particle transfer pipe is connected to the transfer pipe on the upstream side of the shutter, and the shutter is connected to the transfer pipe on the downstream side of the shutter. A gas inlet pipe is connected. Further, the nozzle may be connected to a particle discharge pipe at the rear end side.

[0006]

The particles suspended in the carrier gas are transported together with the carrier gas in a transport pipe having an open shutter, and are sprayed from a nozzle onto the substrate to deposit and form a film. When the shutter is closed, particles passing through the transport pipe upstream of the shutter are discharged to the outside through the transport pipe together with the carrier gas, and particles in the transport pipe downstream of the shutter are introduced into the transport pipe. The gas is discharged to the outside of the transport pipe.

[0007]

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows an example of a forming apparatus for carrying out the method of the present invention. In the figure, reference numeral 1 denotes a carrier gas and particle supply section, 2 denotes a film forming apparatus for forming a film, and 3 denotes a transport pipe. Supply unit 1
Is provided with an evaporation source 6 made of, for example, alumina-coated tungsten for heating and evaporating the film material 5 into particles G in the lower part of the chamber, and a gas introduction pipe 7 for a carrier gas inside the particle generation chamber 4. , And one end of the gas introduction pipe 7 is connected to helium gas as a carrier gas supply source.
It was connected to an inert gas cylinder 8 such as an argon gas via a control valve 9. The material particles G are located above the particle generation chamber 4.
Inner diameter made of stainless steel which transports together with carrier gas
One end of a 6 mm transfer tube 3 is hermetically inserted into and connected to the particle generation chamber 4, and the transfer tube 3 has a stainless steel 0.8 mm inner diameter nozzle 10 at the other end. The film forming chamber 11 of the film forming apparatus 2 was connected to a vacuum pump 12 via an exhaust pipe 14 having a control valve 13. The film forming chamber 11 has a rectangular shape of, for example, a width of 20 mm, a length of 50 mm, and a thickness of 1.times.
Substrate 1 of 0 mm Vycor glass, silicon wafer, etc.
5, a substrate holding device 16 for horizontally moving the substrate 15 was provided. Further, a nozzle 10 provided on the tip side of the transfer pipe 3 connected to the particle generation chamber 4 is hermetically inserted into the film formation chamber 11, and the tip of the nozzle 10 is inserted into the substrate 15 in the film formation chamber 11. And an interval of 0.7 mm.

[0008] Then, an inert gas is introduced as a carrier gas from a gas introduction pipe 7 to a certain pressurized state in the particle generation chamber 4, and the film material 5 is heated by an evaporation source 6 to evaporate into particles G. The particles G and the carrier gas are conveyed to the film forming apparatus 2 via the conveying pipe 3 and are ejected from the tip of the nozzle 10 to form a film on the substrate 15.

Although this configuration is not particularly different from the conventional one, in this embodiment, according to the features of the present invention, a shutter 1 composed of, for example, a ball valve is provided in a part of the transport pipe 3.
7, an electromagnetic valve 18 is provided on the transport pipe 3 on the upstream side of the shutter 17, a feed pipe 19 having one end connected to a vacuum pump or the like (not shown) is connected, and a transport pipe on the downstream side of the shutter 16 is connected. 3 was provided with a solenoid valve 20, and one end was connected to a gas introduction pipe 21 connected to a gas cylinder (not shown) of an inert gas such as helium gas or argon gas. Note that a shutter 17 disposed on the transport pipe 3, a solenoid valve 18 of the transport pipe 19,
The opening and closing operations of the solenoid valve 20 of the gas introduction pipe 21 are interlocked with each other. In addition, the transfer pipe 19 and the gas introduction pipe 21 take into consideration that the particles remaining in the transfer pipe 3 are quickly discharged outward after the shutter 3 is closed.
Is connected to a position close to the shutter 17.

Next, an example of forming an Ag film as a spot-like film using the forming apparatus shown in FIG. 1 will be described. First, the shutter 17 of the transport pipe 3 and the solenoid valve 1 of the transport pipe 19
8 and the solenoid valve 20 of the gas introduction pipe 21 are closed respectively.
Subsequently, after filling the evaporation source 6 in the particle generation chamber 4 of the supply unit 1 with Ag of the film material 5, helium gas is introduced from the gas introduction pipe 7 to constantly maintain the inside of the particle formation chamber 4 at 2 atm. Meanwhile, 400 W of electric power was applied to the evaporation source 6 to evaporate the film material 5 to generate Ag particles G. Next, after predetermined particles G are generated in the particle generation chamber 4, only the shutter 17 of the transport pipe 3 is opened (the electromagnetic valve 18 of the recirculation pipe 19 and the electromagnetic valve 20 of the gas introduction pipe 21 are closed). (Maintenance), and when the inside of the film formation chamber 11 is kept open at atmospheric pressure without operating the vacuum pump 12 connected to the film formation chamber 11 of the film formation apparatus 3, the particle generation chamber 4 and the film formation Room 11
Ag particles G generated in the particle generation chamber 4 due to the pressure difference between the particles are maintained in a floating state in the carrier gas introduced into the particle generation chamber 4, and the particles G are transported together with the carrier gas into the transport pipe 3.
And transported through the transport pipe 3 into the film forming chamber 11 (in the direction of arrow A).

Then, a carrier gas and particles G are sprayed from the nozzle 10 at a flow rate of 10 Torr · l / sec onto the Vycor glass substrate 15 previously held in the substrate holding device 16 to form an Ag film on the substrate 15. At the same time as closing the shutter 17 of the transfer pipe 3, the substrate 15 is moved at a predetermined interval by the substrate holding device 16 at a speed of 7.5 mm / min (in the direction of the arrow X in FIG. 1), and further forwarded while the substrate 15 is moving. Tube 19
The electromagnetic valve 18 of the gas introducing pipe 21 and the electromagnetic valve 20 of the gas introducing pipe 21 are opened, and the particles G in the conveying pipe 3 on the upstream side of the shutter 17 are pressure-fed to the circulation pipe 19 together with the pressurized carrier gas from the particle forming chamber 4. Discharged from the transfer pipe 19 (arrow B direction)
At the same time, helium gas pressurized to a pressure of 2 atm from the gas introduction pipe 19 is introduced into the transport pipe 3 downstream of the shutter 17 as a carrier gas (in the direction of arrow C), and the particles G in the transport pipe 3 are removed. The gas was discharged from the tip of the nozzle 10 together with the carrier gas.

Subsequently, the electromagnetic valve 18 of the transfer pipe 19 and the electromagnetic valve 20 of the gas introduction pipe 21 are closed, and at the same time, the shutter 17 of the transport pipe 3 is opened again to transport the particles G from the particle generation chamber 4 together with the carrier gas. The Ag film was formed on the substrate 15 by spraying from the nozzle 10 through the tube 3. The formation time of the film on the substrate 15 is 3 seconds, and the movement time of the substrate 15 after the film is formed is 8 seconds. This is repeated to continuously form spot-like Ag films on the substrate 15 at a constant interval. Formed. Observation with an optical microscope (magnification: 25) after the formation of the Ag film confirmed that the Ag film was formed without footing in the moving direction as shown in FIG. In addition, the substrate 1
The deposition rate of the Ag film on the substrate 5 is such that the gas flow rate passing through the nozzle with the substrate stopped is 10 Torr · l / sec.
At this time, the deposition thickness was adjusted to 5 μm / sec or more. In addition, when the opening / closing response time of the shutter 17 was examined, it was 0.1 second, and it was confirmed that the transfer of the particles G to the nozzle 10 could be started and stopped accurately.

FIG. 3 shows another embodiment of the forming apparatus of the present invention. In the apparatus shown in FIG. 1, when the shutter 16 is closed, the discharge of the particles G in the transport pipe 3 downstream of the shutter 16 is performed by a nozzle 10. In the apparatus shown in FIG. 3, the discharge of the particles G is performed at the rear end side of the nozzle 10. The difference between the apparatus shown in FIG. 3 and the apparatus shown in FIG. 1 will be described. Tip 3a of transfer tube 3
And a rear end 10 a of the nozzle 10, a control valve 22 was provided, and one end was connected to a discharge pipe 24 connected to an exhaust system 23 such as a vacuum pump. The other reference numerals are the same as those of the forming apparatus shown in FIG.

Next, an example of forming an Ag film as a spot-like film using the apparatus shown in FIG. 3 will be described. The nozzle 10 has an inner diameter of 0.1 mm, the flow rate of carrier gas and particles in the nozzle 10 is 0.88 Torr · l / sec, and the shutter 16 of the transfer pipe 3 is closed to close the shutter 1.
At the time of discharging particles in the transport pipe 3 downstream of the nozzle 6, the control valve 13 of the exhaust pipe 14 connected to the film forming chamber 11 is closed, and the front end 3 a of the transport pipe 3 and the rear end of the nozzle 10 are closed. 10
Then, the control valve 22 of the discharge pipe 24 connected between a and a is opened, and the exhaust system 23 is operated so that the discharge is performed via the discharge pipe 24 (in the direction of arrow D).
An Ag film was formed on the substrate 15 at a constant interval in the same manner as in the embodiment of FIG. 1 except that the movement time of the substrate 15 after forming the film was set to 2 seconds. After the formation of the Ag film, it was observed with an optical microscope (magnification: 150).
It was confirmed that an Ag film having no footing in the moving direction was formed as shown in FIG.

Therefore, an Ag film is formed in a spot shape on the substrate 15 by using the same method as that of the embodiment shown in FIG. 3 without using the discharge pipe 24 arranged at the rear end of the nozzle 10 at all. As a result, the tailing was observed. This is to be expected from the volume and gas pressure from the shutter to the tip of the nozzle, and the gas flow through the nozzle. These relationships can be expressed as follows. Volume × gas pressure / gas flow rate = gas replacement time (sec) The volume from the shutter to the tip of the nozzle in the embodiment of FIG. 3 was 0.6 cc, and the pressure was 2 atm × 76.
0 Torr / atm and the flow rate is 880 Torr · cc / s
When ec (cc converted value) is used, the gas replacement time, that is, the delay time of the substrate movement, is calculated from these numerical values as follows.

[0016]

(Equation 1)

That is, if the substrate is moved after a lapse of one second or more after the opening and closing of the shutter, a film without footing is formed. By the way, after closing the shutter 1.5
Various experimental results confirmed that a film without tailing was formed after a lapse of seconds.

By arranging the discharge pipe 24 at the rear end of the nozzle 10 as in the apparatus shown in FIG. 3, particles in the transport pipe downstream of the shutter after the shutter is closed can be removed from the discharge pipe without passing through the nozzle. The nozzle can be used quickly, a small-diameter nozzle 10 can be used, a small-diameter film can be easily formed, and particles do not stay in the film-forming chamber 11. The formation chamber can always be kept clean.

In the above-mentioned embodiment, the film material to be formed is formed by directly evaporating the film material by the in-gas evaporation method.
Particles of the film material are prepared in advance, and the particles are accommodated in, for example, a glass bottle-shaped container, and a carrier gas is introduced into the container from the end of a gas introduction pipe connected to the container, and the particles are transferred to the carrier gas. It may be made to float inside, and this may be pressure-fed to a conveyance pipe. In the above-described embodiment, the Ag film is described as the film formed on the substrate. However, the present invention is not limited to this. For example, a metal film such as a Cu film, an Au film, or a Ni film, or a Ni—Cr film may be used. , Pb-Sn film,
It can be widely applied to formation of an alloy film such as an Ag-Pd film. In the above-described embodiment, the substrate is made of Vycor glass. However, the present invention is not limited to this. For example, the present invention can be applied to substrates such as an alumina substrate and a silicon wafer substrate. In the above embodiment, the spot-like film is formed on the substrate. However, the present invention is not limited to this. By adjusting the movement of the substrate and the opening and closing times of the shutter, a long continuous film is formed. Alternatively, a mixed film having a long length and a short length can be formed.

[0020]

As described above, according to the forming method of the present invention, when the shutter is closed, the particles in the transport pipe upstream of the shutter are sent to the transport pipe together with the carrier gas, and the gas is introduced into the transport pipe downstream of the shutter. Since the particles are introduced, the particles are quickly discharged to the outside of the transfer tube and do not remain in the transfer tube and nozzle, so that aggregates of sediment of particles adhere to the transfer tube and shutter as in the conventional device. Thus, there is an effect that when the shutter is opened again without closing these particles, the particles are smoothly transported in the transport pipe to form a uniform film without footing. Further, when using the forming apparatus of the present invention, a transport pipe for particles is connected to a transport pipe on the upstream side of a shutter arranged in the transport pipe, and a gas introduction pipe is connected to a transport pipe on the downstream side of the shutter. Therefore, there is an effect that it is possible to provide a forming apparatus in which particles in the transport pipe can be quickly discharged to the outside of the transport pipe when the shutter is closed, and no particles remain in the transport pipe and the nozzle. When a discharge pipe for particles is connected to the rear end of the nozzle, particles in the transfer pipe downstream of the shutter should be discharged directly from the discharge pipe without passing through the film forming apparatus on which the substrate is placed. Therefore, there is an effect that the particles do not remain or scatter in the film forming apparatus, so that the inside of the film forming apparatus is not contaminated, and a nozzle having a small inner diameter can be used.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of one embodiment of a film forming apparatus of the present invention.

FIG. 2 is a micrograph of the particle structure of a spot-like film formed on a substrate using the apparatus of FIG.

FIG. 3 is an explanatory diagram of another embodiment of the film forming apparatus of the present invention.

FIG. 4 is a micrograph of the particle structure of a spot-like film formed on a substrate using the apparatus of FIG.

FIG. 5 is an explanatory diagram of a conventional film forming apparatus.

[Explanation of symbols]

 Reference Signs List 3 transport pipe 7 gas introduction pipe 10 nozzle 15 substrate 17 shutter 19 forward pipe 21 gas introduction pipe 24 discharge pipe G particles

Claims (3)

(57) [Claims] In a method of forming a film by a gas devotion method in which particles of a film material are conveyed together with a carrier gas by a conveying tube and ejected from a nozzle to form a film on a substrate, a shutter capable of opening and closing the particles is provided. After stopping at the closing of the gas, the particles and the carrier gas are circulated into a transport pipe different from the transport pipe upstream of the shutter, and gas is introduced into the transport pipe downstream of the shutter. A method of forming a film by a method. 2. An apparatus for forming a film by a gas devolution method, comprising: a transfer pipe for transferring particles together with a carrier gas; a substrate; and a nozzle for spraying particles together with the gas onto the substrate. A gas devotion method characterized in that an openable and closable shutter is disposed at the shutter, a transport pipe for particles is connected to a transport pipe on the upstream side of the shutter, and a gas introduction pipe is connected to a transport pipe on the downstream side of the shutter. Film forming equipment. 3. The film forming apparatus according to claim 2, wherein a discharge pipe for particles is connected to a rear end of the nozzle.