Method and device for forming thin film

[Detailed Description of the Invention]

(Technical field) This invention relates to a method for forming thin film and its device. This invention relates to the plasma producing-film method by the glow discharge plasma under atmospheric pressure in detail. (Conventional technology) From before, the producing-film method by low-pressure glow discharge plasma is known widely, and even if also industrially applied to various fields, it is. It is also known that there is what is called an organic plasma coating method that carries out thin film formation by plasma-ization of organic compound gas as a producing-film method by this low-pressure glow discharge plasma. For example, in a vacuum vessel, the method of carrying out precipitation formation of the amorphous carbon film, the method of forming the plasma polymerization film of unsaturated hydrocarbon, such as ethylene, etc. are on a silicon substrate or a glass substrate by making hydrocarbon gas into the shape of plasma. However, each producing-film method by the low-pressure glow discharge plasma known from these former is 1x10.^-5~1x10^-3The fault that it cannot but be [ the device of this low-pressure condition formation and equipment / the film production to a large area board ] necessary and to the difficult thing which also has an expensive manufacturing cost since it becomes a reaction under the vacuum about Torr is Oh. The artificer of this invention inquired wholeheartedly, in order to conquer such a fault, and he completed the producing-film method by the glow discharge plasma under the easy atmospheric pressure of cost reduction of a device and equipment, and the film production to a large area board here. Those of this background and Noodle is research of years of silent electric discharge for ozone evolution by an artificer, and the analysis of the reaction mechanism about the plasma producing-film method, and is Oh. About the reaction by the glow discharge plasma under atmospheric pressure, this artificer has proposed the surface treatment method by the Fluorine gaseous plasma of a plastic surface, further develops this processing method, and is already very much for completing the producing-film method. (The object of an invention) This invention is made in view of the situation as above, and cancels the fault of the conventional low-pressure glow discharge plasma producing-film method, The cost fall of a device and equipment is aimed at, and it aims at providing the film production method according to the easy bottom glow discharge plasma of atmospheric pressure and its device of the thin film formation to a large area board. (Indication of an invention) This invention provides the method for forming thin film carrying out thin film formation of the monomer gas which was mixed with inactive gas and introduced in the reaction vessel which has a top electrode which consists of a plurality of small-gage wires on the base surface as the shape of plasma under atmospheric pressure, in order to realize the above-mentioned object. This invention also provides the film production device which can be used conveniently for this method. As a film production device, it has a top electrode which consists of a plurality of small-gage wires, a solid dielectric is further arranged on the upper surface of the lower electrode which arranges a base, and what arranges the perforated pipe which diffuses gas uniformly near the base surface is shown. The thing illustrating this is Drawing 1. Although this Drawing 1 is one example, it has top electrode 2 and lower electrode 3 which impress the high voltage in the reaction vessel which consists of bell Jeyer 1 made from Pyrex, for example, and constitutes top electrode 2 by a plurality of small-gage wires. Solid dielectrics 4, such as glass, ceramics, and a plastic, are provided in the upper surface at lower electrode 3. Base 5 of the shape of a plate etc. is equipped on this solid dielectric 4. helium, Ne, Ar, and N₂He introduces the mixed gas with monomer gas, such as hydrocarbon as the inactive gas and thin film formation materials of etc, into perforated pipe 8 which has a plurality of puncturing 7 from feed port 6, and is trying for mixed gas to diffuse it from this puncturing 7 uniformly to base 5. Unreacted gas, inactive gas, etc. are discharged from the gas exit of a reaction vessel. It is, even if it equips three copies of lower electrodes with temperature sensor 9 and heating heater 10. It can also have a cooling device. For example, in the film production device of this invention that can be illustrated as mentioned above, the reaction region in bell Jeyer 1 is maintained at the conditions of atmospheric pressure. For this reason, the device or equipment of a vacuum system are not needed like the conventional low-pressure glow discharge plasma film production device. As inactive gas used for a reaction, they are as above-mentioned helium, Ne, Ar, and N.₂Although the proper thing of etc can be used as a simple substance or a mixture, in order to make sputtering to the generated thin film into the minimum, it is preferred to use helium with light mass. The monomer gas as thin film formation materials mixed with this inactive gas can form a desired plasma polymerization film using the arbitrary things of the hydrocarbon which does not have or have unsaturated hydrocarbon, such as ethylene and propylene, halogen, and other functional groups. Although the mixture ratio of inactive gas and monomer gas is not exceptionally restrictive, it is preferred to make gas concentration into about 90% or more. Gas may also mix and Use two or more sorts of things. As for plasma-izing of this mixed gas, it is desirable to carry out in the state where diffusion supply of the gas is uniformly carried out in the plasma region near the base. As a means for this, it can be considered as perforated pipe 8 shown in Drawing 1, or other proper means. this case where that shape and structure may be chosen with the size of a device, and the size of an electrode -- the inflow of external gas (oxygen, nitrogen, etc.) -- Hinder -- it is made like. Although impression of the high voltage performs plasma formation, the voltage in that case can be decided according to the heat resistance of the polymerization film to generate, generation speed, etc. Film production speed is controllable by control of frequency and voltage. For example, as shown in Drawing 1, generation of making small the difference of equalization of film production and the film thickness of the center of substrate 5 and the circumference and stable glow discharge is enabled by using a small-gage wire for top electrode 2, and allocating solid dielectric 4 in lower electrode 3. In the case of this Drawing 1, top electrode 1 can make film production effective further by making it rotate. Usually, under the conditions of atmospheric pressure, although glow discharge does not arise easily, it makes possible highly stable glow discharge and its plasma production using inactive gas, using the electrode which consists of a plurality of small-gage wires, and also by using a solid dielectric. Depending on the gas which can use proper materials, such as ceramics, glass, and a plastic, as a base, and it uses, halogen for promotion of a reaction, oxygen, hydrogen, etc. may further be mixed. Next, an example is shown and this invention is explained in more detail. Example 1 On the following conditions, polyethylene membrane was formed from the ethylene monomer using the device (electrode 30-mm width in diameter, 10 mm of inter electrode distances) shown in Drawing 1. (a) Mixed gas He:4500SCCM Ethylene: 3.6SCCM (b) Glow discharge Atmospheric pressure 3000 Hz, 1.05 kV, 3 mA (c) Substrate Cover glass To the substrate face, polyethylene membrane was obtained by film production speed 12500A/2hr. It is transparent, adhesion intensity is good, and it is Oh. Example 2 The polymerization film of ethylene was formed like Example 1 on the following conditions. (a) Mixed gas He:4500SCCM Ethylene: 6.0SCCM (b) Glow discharge Atmospheric pressure 3000 Hz, 1.25 kV, 6 mA (c) Substrate Cover glass Polyethylene membrane was obtained by film production speed 2100A/2hr. It is transparent, adhesion intensity is good, and it is Oh. Example 3 The polymerization film of ethylene was formed like Example 1 on the following conditions. (a) Mixed gas He:4500SCCM Ethylene: 2.5SCCM (b) Glow discharge Atmospheric pressure 3000 Hz, 1.01 kV, 2.2 mA (c) Substrate Cover glass Polyethylene membrane was obtained by film production speed 16800A/5.5hr. It is transparent, adhesion intensity is good, and it is Oh. Example 4 The polymerization film of ethylene was formed like Example 1 on the following conditions. (a) Mixed gas He:4500SCCM Ethylene: 3.6SCCM (c) Glow discharge Atmospheric pressure 3000 Hz, 1.14 kV, 3 mA (c) Substrate 0.2 mm of quartz thickness glass Polyethylene membrane was obtained by film production speed 9000A/2hr. It is transparent, adhesion intensity is good, and it is Oh. The unevenness of the thickness in the portion which produced the film respectively by the circumference and the center section of the electrode (30 mm in diameter) like Example 1~3 when thickness was evaluated about this polyethylene membrane is Ivy in few very much. (EFFECT OF THE INVENTION) Compared with the conventional low-pressure glow discharge plasma producing-film method, the device for formation of a vacuum system and equipment are not required, moreover, the operation for it also has them, it excels in the cost fall effect, and handling is easy as this invention was explained in detail above. [ unnecessary ] There is no pressure variation by receipts and payments of a sample etc., and the influence by the pressure fluctuation at the time of film production is also small. And by this invention, by the operation under atmospheric pressure, since Then and the device are easy, it becomes easy [ the polymerization thin film formation to a large area board ]. Compared with the former, restrictions of the scale accompanying vacuum system formation are also small, and end. The acquired thickness difference of the circumference and the central part of a thin film is also small.

[Brief Description of the Drawings]

Drawing 1 is an eye squinting sectional view showing the film production device as an example of this invention. 1 ...... bell Jeyer, 2 ...... top electrode, 3 ...... lower electrode, 4 ...... solid dielectric, 5 ...... base, 6 ...... mixed gas feed port, 7 ...... puncturing, 8 ...... perforated pipe, 9 ...... temperature sensor, 10 ...... heater.