JPS58141380A - Production of thin film element - Google Patents

Abstract

PURPOSE:To improve the weather resistance of a thin film formed on a flexible substrate and to stabilize the characteristics thereof, by treating the surface of the thin film vapor deposited on said substrate under an oxidative discharge atmosphere, then irradiating condensed light thereto. CONSTITUTION:A flexible substrate 1 is introduced from a let-off shaft 4 into the vapor deposition chamber 7 of a vacuum vessel 6 by means of a roll 2, and an evaporating source 11 is bombarded and heated by the accelerated electrons radiating from an electron beam generating source 12, whereby a thin film is vapor deposited on the substrate 1. Electric power is supplied from an electric power source 16 to a glow discharge electrode 15, whereby a glow treatment is applied on the substrate. The substrate 1 is further introduced through a differential pressure holding chamber 9 into an optical treatment chamber 10 by means of a roll 3. Here, the light of a light source 18 such as a halogen lamp is condensed onto the vapor deposited layer on the substrate 1 by a reflecting and condensing mirror 19, whereby an optical treatment is applied thereon. Thus, the surface defects, internal defects and surface contamination remaining in the stage of forming the thin film are removed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the production of a thin film functional element by forming a thin film of semiconductor, magnetic material, etc. on one side of a flexible substrate such as a polymer molded product or a thin stainless steel plate. The purpose of the present invention is to provide a manufacturing method that is used to improve weather resistance and stabilize properties by removing surface defects and internal defects 2 surface contamination that remain during thin film formation.

Vapor-deposited tapes and amorphous silicon solar cells, which have recently been developed and are now in practical use, have problems with weather resistance and changes in characteristics over time.Especially vapor-deposited tapes used for videos used for short wavelength recording. In the case of tape, compared to solar cells, the thickness is limited due to space loss when providing a protective layer on the surface9, and the thickness is extremely thin, at most 200A, and conventional thin film formation is not possible. The thickness is such that it is difficult to obtain a film with sufficient protective ability by other means.

This is because even if it is known that a dense oxide film can be obtained by increasing the temperature during film formation, especially when a polymeric material is used for the substrate, this cannot be put into practice.

Therefore, it becomes necessary to find ways to improve the weather resistance and stability of the magnetic layer itself.

One possible method is to achieve partial oxidation, in which the surface of crystal grains is coated with an oxide film of the material, by devising the introduction of oxygen during vapor deposition.This method is a reasonable solution. However, the deposition rate used to produce magnetic tape on an industrial scale is 20
00 A/see, which is extremely fast and is 10 to 100 times faster than when used for research in a laboratory.

Therefore, even if the introduction of oxygen is devised, the oxide film formed on the surface of the crystal grains is incomplete and does not have sufficient protective ability.

In solar cells, gases such as H2,02 are used during evaporation, sputtering, glow discharge deposition, and glow discharge polymerization to reduce dangling bonds, but this can cause defects not only on the surface but also inside. However, the leakage current increases and only a low electromotive force can be obtained.

The method used to deal with these problems is a method called aging.

This is done by keeping it in an environment with controlled temperature and humidity for a certain period of time, but when increasing the acceleration of this method,
Since a polymer is used as the substrate, the upper temperature limit is as low as 50° to 60°C.

Therefore, by taking a longer time, we expect an aging effect, but even if we just lengthen the time, defects that do not move will remain, and it will not be possible to provide a sufficient "1" protective layer, and the internal stability will also be unsatisfactory. I had no choice but to do so.

The present invention has been made in view of this point, and following the vapor deposition process (a concept that also includes sputtering, ion blating, plasma, CvD, etc.), the surface of the vapor deposited layer is exposed to an oxidizing glow discharge atmosphere, and then the pressure is reduced. This method eliminates imperfections in the protective layer by allowing the vapor deposited layer underneath to absorb light, maintaining good heat transfer from the back side of the substrate, and causing the vapor deposited layer to experience as high a temperature as possible. The present invention will be explained below using the drawings.

The figure shows an example of a device for carrying out the invention.

As shown in the figure, a flexible substrate 1 such as a polymer substrate moves along the circumferential side of a temperature-controlled row 22, and further moves along another temperature-controlled roller 3, and moves along the feeding axis. 4 to the winding shaft 6.

The vacuum chamber 6 includes a vapor deposition chamber 7, a glow processing chamber 8, and a differential pressure holding chamber 9.
, and a light processing chamber 10. Of course, this division is not absolute and can be devised as appropriate.

First, in the case of a magnetic tape, vapor deposition is performed by impact-heating the evaporation source 11 by accelerated electrons emitted from the electron beam generation source 12, and then applying vapor to an oxygen partial pressure of 3 x 10''l', for example.
In □rr, the incident angle is limited by a mask 13 and the beam is directed toward the substrate.

Maintaining the oxygen partial pressure is also important for controlling magnetic properties, but in the figure, since the pressure when performing glow processing after vapor deposition is higher than during vapor deposition, the needle valve 14 is inserted into the glow processing chamber 8 from the outside. by adjusting the gas G-1 (oxygen in this case)
is introduced, and relies on gas flowing from the glow chamber 8 into the vapor deposition chamber 7 by a pressure difference.

Of course, if the guiding gases are different for glow treatment and vapor deposition, and if the above adjustment is insufficient, then it is of course necessary to introduce gases separately, and this is not a limitation of the present invention.

In the glow treatment, a glow discharge electrode 16 is placed close to the rotating roller 2, and a power source 16 is used to supply alternating current or direct current.

It is configured to supply power selected from high-frequency waves or the like.

The glow discharge electrode may be formed by arranging a plurality of bar-shaped electrodes extending in the width direction and insulated from each other, or may be formed into another shape as appropriate.

The glow-treated substrate passes through the differential pressure holding chamber 9 and is led to the optical processing chamber 1o.

The light treatment is performed using temperature-controlled light that is focused on the vapor deposited layer on the polymer substrate along the circumferential side of the rotating roller 3.

This light is obtained by disposing a light source 1B such as a halogen lamp near the focal point of the elliptical reflecting mirror. Although a single light source is shown in the figure, it is of course not limited to this.

However, the light source is preferably rod-shaped in the width direction.

The important point here is that the substrate does not have heat resistance, so it is important to inject energy only into the deposited layer for a short period of time to make it experience a high temperature state, so that the substrate is not damaged. If the pressure in the processing chamber is below several Torr, the heat transfer between the rotating roller and the substrate will depend on the contact area between them, which will stabilize the force perpendicular to the circumferential surface of the rotating roller. And it is necessary to make it larger.

This can be achieved, for example, by using a high-voltage electron beam of 25 KeV or more to heat the evaporation source and injecting reflected electrons into the substrate, or by actively injecting electrons separately.

However, when this method is used, it is necessary to perform glow discharge treatment on the back surface of the substrate to neutralize the charge.

20 schematically shows a discharge electrode for this purpose, and 21
is its power source.

If the pressures for the glow discharge treatment and light treatment cannot be adjusted at the same time, it is necessary not only to introduce gas Q-2 by adjusting the valve 22 to the needle 1, but also to create a separate space for exhaust. , omitted here. 23, 24, 2
5 and 26 are vacuum evacuation systems, which can be selected from existing pumps depending on the required degree of vacuum. Hidden 2
7, 28, and 29 are also designed and arranged in consideration of the pump, depending on the degree of vacuum required in each space.

30 is a free roller, and expander rollers, nip rollers, etc. are omitted. 31 is an insulation introduction terminal.

Next, the present invention will be specifically explained in detail.

Here, experimental conditions in Examples of the present invention are listed.

Rotating roller (for vapor deposition and glow oxidation treatment): diameter 1? FL
, Temperature: 20°C Rotating roller (for light processing): Diameter: 30 mm, Temperature: 20"C Base &: Polyethylene Tele 7 Talate Film (Thickness: 9mm)
5 μm) Vapor deposition conditions Substrate winding speed: 30 m/min Back surface resistance: 330 V 0.4 A The processing conditions for the vapor deposited layer are shown in the table below.

(Blank below) Page 9 The glow treatment and light treatment were performed under the same conditions as 1-A in the table above, and the vapor deposition materials were Co80%Ni2O%, C075%Ni2
2-A is a sample obtained by changing the concentration to 5%.

The sample was designated as 2-B, and the untreated product was designated as 2-C.

Each sample prepared under the above conditions was heated at 6o''C.
95% RHO environment for 4 weeks, 1oba for 12 weeks
The total amount of magnetic flux measured by a vibrating sample magnetometer when the sample was left standing was compared with the initial value to determine the increase or decrease.

At the same time, A
r 9 X 1O-3Torr, IE (23X 10
13.56 MH in a discharge gas atmosphere of Torr
Thickness: 0.6μm by high frequency sputtering method
An amorphous silicon film was formed, and changes in electrical conductivity were also investigated. f of the sample with silicon film formed is 3-A
.

Let them be B and C.

The processing conditions for sample 3A + s B are the same as for each sample 1.
-B and 1-1). 3-(' is an untreated product.

The test results for each sample are shown in the table below.

In other environments, Teno, 30″080%RH, 40’C90
%RH* "0100%RH, 40'C90%RH.

The performance of the device according to the present invention was stable even in a storage test in a gas atmosphere containing 20 ppm of SO2 gas, in a hot spring area, on the coast, etc.

As is clear from the above description, the present invention is of great value not only in the electronics field in which thin film applications have become active in recent years, but also in other fields.

4. Brief explanation of the drawings 1. .

The figure is a diagram showing an example of an apparatus for implementing the present invention.

1...Substrate, 2,3...111111@C1-ra, 6...ee/vacuum chamber, 7...Mountain evaporation chamber, 8...
...Fist glow processing room, 10...Light processing room, 11...
Evaporation source, 15...Glow processing electrode, 18...River/light source, 19...Reflecting condenser mirror.

Name of agent: Patent attorney Toshio Nakao, 1 person

Claims (1)

[Claims] It is characterized by comprising a step of forming a thin film on a flexible substrate by vapor deposition, a step of treating the surface of the thin film in an oxidizing discharge atmosphere, and a step of irradiating the surface of the thin film with focused light. Manufacturing method of thin film element 0