JP3021624B2 - Vacuum film forming apparatus and method for manufacturing vapor-deposited film - Google Patents

Description

The present invention relates to a vacuum film forming apparatus and a method for manufacturing a vapor-deposited film.

More specifically, the present invention relates to a film forming apparatus capable of measuring a vapor deposition temperature in real time when forming a vapor deposition film while running a rolled film continuously, and using the result to control vapor deposition conditions.

(Prior Art) Various vacuum film forming methods such as vacuum deposition and sputtering are widely used as thin film manufacturing techniques. Recently, a winding-type film forming apparatus has been developed, and a vapor-deposited film in which a thin film of a transparent metal compound or the like has been formed on a rolled-up plastic substrate has been manufactured and used as an industrial material in various fields.

One of the important conditions in forming a thin film is setting and controlling the substrate temperature. This is because the structure and physical properties of the growing film are affected by the substrate temperature, and it is important to control the substrate temperature during film formation in order to improve film quality and obtain stability. is there.

At present, there is a method in which a cooling roll is provided between an unwinding roll and a take-up roll, an evaporation source is arranged below the cooling roll, and a thin film is formed while holding the base film on the cooling roll. I have. The temperature of the substrate film is controlled by passing a constant temperature circulating liquid such as water or a refrigerant into the cooling roll.

(Problems to be Solved by the Invention) However, it is difficult to control the temperature stably because the base film is a plastic having relatively low thermal conductivity, and the temperature changes depending on the thickness of the plastic and the traveling speed. . Therefore, in order to control the physical properties and structure of the film, it is necessary to measure the temperature of the base film thin film forming surface in real time.

Therefore, the present invention provides a film forming apparatus and a method for manufacturing a vapor-deposited film capable of measuring the temperature of the base film thin film forming surface in real time, thereby easily controlling the film forming conditions and controlling the physical properties and structure of the film. The purpose is to do.

(Means for Solving the Problems) In order to achieve this object, the invention according to claim (1) provides an unwinding roll for unwinding a base film and a vapor deposition film in a closed system having a vacuum suction mechanism. Take-up roll, cooling roll arranged between the unwind roll and take-up roll along the running direction of the film, evaporation source arranged below the cooling roll, cooling roll and winding along the running direction of the film Provided is a vacuum film forming apparatus comprising an infrared sensor disposed between take-up rolls.

In the invention according to claim (2), the base film is run while being held by a cooling roll in a closed system in a vacuum state, and a transparent material is deposited on the surface of the base film on the cooling roll. Provided is a method for producing a vapor-deposited film, characterized by measuring infrared rays having a wavelength that is blocked by the obtained vapor-deposited film and transmitted through a base film.

(Detailed Description of the Invention) The base film according to the present invention needs to be transparent to infrared rays used for measurement. For example, polyolefin films such as polyethylene and polypropylene,
It is a plastic film such as a polyester film and a polyamide film. FIG. 2A shows the infrared transmittance of the polyethylene film, and FIG. 2B shows the infrared transmittance of the polyester film.

In addition, a transparent metal compound can be used as a thin film forming material. Transparent means substantially transmitting visible light, and examples thereof include silicon oxide, magnesium oxide, tin oxide, and aluminum oxide.

As shown in FIG. 1, the apparatus of the present invention comprises a completely closed system, and is provided with a vacuum suction mechanism (90) in order to make the inside of the system vacuum.

An unwinding roll (11) for a base film (1) for forming a thin film is disposed in the system, and the base film (1) is unwound continuously. The unwound base film (1) travels while being embraced by the cooling roll (2) via the guide roll (51) provided as needed, and again returns to the guide roll ( It is taken up by a take-up roll (12) via 52).

The cooling roll (2) may be the same as a conventional cooling roll, and controls the temperature by passing water or a refrigerant therein. In order to control the structure and the like of the thin film by the temperature of the cooling roll (2), an evaporation source (3) is arranged below the cooling roll (2), and the base film (1) is held by the cooling roll. It is necessary to form a thin film between them.

The thin film may be formed by a method such as vacuum deposition such as resistance heating or electron beam heating, or sputtering.

An infrared sensor (4) is arranged between the cooling roll (2) and the winding roll (12) along the running direction of the base film (1). Since the amount of infrared radiation of the thin film formed on the base film (1) varies depending on the temperature, the amount of infrared radiation is measured by the infrared sensor (4) to determine the boundary surface between the base film (1) and the thin film. Temperature can be measured.

The wavelength of the infrared light to be measured needs to be cut off by the thin film in order to block the infrared light transmitted through the thin film and the base film (1) from the opposite side to prevent an error. FIG. 3A shows the infrared transmittance of silicon oxide, and FIG.
Shows the infrared transmittance of magnesium oxide. As can be seen from FIGS. 2A and 2B, when the base film (1) is a polyethylene or polyester film, it is desirable to detect infrared rays having a high transmittance and a wavelength of 4 to 6 μm. Also, as can be seen from FIGS. 3A and 3B,
Infrared light having a wavelength of 4 to 5 μm when the thin film is silicon oxide, and 5 to 6 μm when the thin film is magnesium oxide.

FIG. 1 shows a case where the infrared sensor (4) is located on the side opposite to the thin film. In this case, the temperature at the interface between the base film (1) and the thin film can be measured. When the infrared sensor (4) is arranged on the opposite side, it is possible to measure the surface temperature of the thin film.

Further, in order to control the substrate temperature during film formation, it is desirable to provide a heating source in the cooling roll (2). The heating source may be a heating roll (6) with a built-in electric heater.
Many heating rolls (6) in the width direction of the base film (1)
Can be arranged and controlled individually, but in order to make the heating temperature uniform, a heat transfer roll (7) is arranged between the heating roll (6) and the cooling roll (2), and the cooling roll ( It is desirable to control the temperature of 2). Further, a non-contact heat radiation heater or the like may be used as the heating source.
The heating source is arranged just before the base film (1) comes into contact with the cooling roll, and finely adjusts the surface temperature of the cooling roll (2) by turning on / off the heater based on information from the sensor (4). . By such fine adjustment, the base film (1)
By controlling the surface temperature of the thin film, it is possible to control the physical properties and structure of the thin film with the liter time.

(Example) The apparatus shown in Fig. 1 was used. Each condition is as follows.

Vacuum degree 10 ^-3 Pa Cooling roll 1 m diameter cylinder (cooled with liquid nitrogen) Heating roll 4 silicon rolls with built-in electric heater) Heat transfer roll 1 silicon roll Base film 500 mm wide, 12 μm thick polyester film Thin film material Silicon oxide Evaporation source heating method Resistance heating (1400 ° C heater) Evaporation effective length 300mm Running speed 2m / sec Thin film thickness About 0.2μm Infrared sensor InSb sensor (detects 4-5μm infrared rays) Arranged and the mirror reflected infrared light is detected through the CaF window.

Set temperature (thin film forming surface) 75 ° C. When a thin film was formed by such an apparatus and conditions, no unevenness was observed in the physical properties and structure of the thin film in the width direction and the flow direction of the base film, and a uniform thin film could be formed. .

(Effects) According to the present invention, it is possible to provide a film forming apparatus and a method of manufacturing a vapor-deposited film capable of measuring a temperature at the time of forming a thin film in real time, thereby controlling film forming conditions and controlling physical properties and structure of the film. Can be facilitated.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an apparatus showing an embodiment of the present invention, and FIG.
2 and FIG. 2B are graphs showing the infrared transmittance of a polyethylene film and a polyester film, respectively, and FIGS. 3A and 3B are graphs showing the infrared transmittance of silicon oxide and magnesium oxide, respectively. (1) Base film (11) Unwind roll (12) Take-up roll (2) Cooling roll (3) Vapor deposition source (4) Infrared sensor (6) Heating roll (90) ... Vacuum suction mechanism

Claims (2)

(57) [Claims] 1. An unwinding roll for unwinding a base film, a winding roll for winding a vapor-deposited film in a closed system having a vacuum suction mechanism, and a winding roll between the unwinding roll and the winding roll along the running direction of the film. Cooling rolls, placed in
A vacuum film forming apparatus comprising: a transparent material evaporation source disposed below a cooling roll; and an infrared sensor disposed between the cooling roll and a winding roll along a running direction of the film. 2. A substrate film is run while being held in a cooling roll in a closed system in a vacuum state, and a transparent material is deposited on the surface of the substrate film on the cooling roll, and then blocked by the obtained deposited film. A method for producing a vapor-deposited film, characterized in that infrared light having a wavelength transmitted through a base film is measured.