JPS6070694A - Method of producing thin film el device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention is directed to a thin film El, (relectroluminescence) device, and in particular to a method for manufacturing a thin film 1jL panel with a moisture-proof protective coating.

Technology Background When a thin-film AC EL panel is operated in a state where it is exposed to moisture, moisture penetrates into the thin film, and gases (hydrogen gas and oxygen gas due to electrolysis of water) are generated at the interface of the thin film due to the high electric field during operation. It is known that this phenomenon causes the thin film to peel off.

Conventional technology and problems As a method to prevent the above phenomenon, some methods have been adopted in which the entire thin film is covered with a glass plate, hermetically sealed, and then filled with oil to protect it from moisture (oil sealing method). . but,
This method has problems such as: (1) the structure becomes complicated, (2) the weight of the panel increases, and (2) the process becomes complicated and costs increase.

- With the aim of demonstrating the features of a solid-state display using a brim thin film, l! A method of covering the entire surface with a protective film after forming the 3L panel has also been attempted, and resin or other insulators have been used as the protective film.

However, with this method, when dielectric breakdown occurs in the cell due to light emission from the E'L pad, the protective film is also damaged due to heat damage, and moisture begins to form from there, so the peeling phenomenon is completely prevented. I can't do it and it's not practical.

Therefore, it has been proposed to initially age the EL panel and then form a protective film to prevent damage to the protective film and thereby eliminate the above-mentioned disadvantages. However, researchers have found that even when this aging is performed, there is a problem in that external moisture infiltrates the thin film, resulting in peeling of the thin film.

OBJECTS OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and provide a method for manufacturing a moisture-proof protective film type thin-film HL device that can be put into practical use.

Structure of the Invention In order to achieve the above object, the present invention provides a thin film g.
The initial aging of LPL is determined by water vapor partial pressure 1o-3To
It is characterized in that it is carried out in an atmosphere below rr, and then a moisture-proof protective film is formed.

Example of the invention rA1 Figure 1 shows a thin film JD L produced by the method of the invention.
An example of a panel is shown. Transparent polarization (thickness: 2,000 layers) made of indium tin oxide (approximately 5% tin) or the like on a glass substrate 1; an insulating layer (thickness: 3,000 layers) made of 4csi N or the like on 'c+ilJ; Luminescent layer (7000 layers thick) made of Zn8 mixed with 4,
On top of that is an insulating film (thickness: 500 mm) made of s; 3N4, etc.
0 people) 5, and on top of that, the °irL pole (thickness 2
000 people) 6 are formed, and these thin films are covered with a moisture-proof protective film (thickness: 100 μm) 7 made of, for example, resin (eg, epoxy resin, fluororesin). The transparent polarization 2 and the 'fIL pole 6 are wired perpendicularly to the X-axis direction and the Y-axis direction, respectively, to form a matrix-like light emitting element group μ. Since this ML panel has been aged before the formation of the protection M7, dielectric breakdown 8 occurs in a portion of the thin film with low dielectric strength, and the protective film 7 covers the thin film after the dielectric breakdown.

Figure 142 shows ffL regarding the voltage applied to the EL panel,
This is a graph of the number of insulated waves Ja and the emission)'c luminance of <Nel. In the figure, f″JLJ at voltage VA (for example, 200V)
The brightness i required for the L panel can be obtained. As the voltage increases, the number of dielectric breakdown points and mosquitoes increases, and then decreases. Therefore, if the initial aging is changed to a voltage V,
If the voltage VB is about 40 V higher, dielectric breakdown can be prevented when the EL panel is used at the voltage VA. At this time, it should be noted that the brightness characteristics initially represented by curve AA change to curve BB after initial aging.
This means that the brightness characteristics change as expressed by .

The present invention is characterized in that the initial aging prior to the formation of the protective film is carried out in an atmosphere with a water vapor partial pressure of 10-5'I'Orr or less. Initial aging, that is, application of a voltage between the electrodes, must be carried out under extremely low water vapor pressure, otherwise the thin film will peel off, which is not practical. Low water vapor pressure can be achieved by creating a high vacuum or a dry nitrogen gas atmosphere.

As shown in Figure 3, voltages can be applied to the x=4 extreme end and the Y% extreme end of a 1!3L panel with transparent polarization and At electrodes formed, such as A/, etc. The shorting plates 10 and 11 of are fixed with springs 12. This is t14
1113, connect the wiring 14 and 15, valve the ridge introduction terminal 16, and connect it to the external EL panel drive source 17. Close the leak pulp 18 and remove the rough pulp 19
Open the vacuum chamber 13 to approximately 5 x 10"' Torr.
Exhaust to r. Then, the roughing valve 19 is closed, the main valve 20 is opened, and the inside of the vacuum chamber 13 is
0-' Perform main evacuation (exhaust) with Torr i.

During these exhaust operations, the heater 21 is energized to 200 mA to effectively remove moisture contained in the EL panel.
Preferably, the baking treatment is performed at ~300°C. (100 Hz to 1K) from the EL drive power supply 17 to create an environment in which moisture is not affected by high vacuum conditions.
Pulse driving is performed at a frequency of lz for about one hour, for example.

EJ and the panel's actual operating voltage VA are determined by the luminance of the light emitted. The voltage width Vs-VA between the initial aging solder pressure VB and the working voltage VA is the voltage margin against dielectric breakdown, so it is preferable that it be as large as possible, but if it is too large, dielectric breakdown during initial aging will occur excessively, resulting in ffL. There is a risk of destroying the child.

V! 1-VA: 50 to 40V is considered to be light. VAd example, for example, about 180 to 220 ■ 17
Immersive.

In this way, the voltage VB is applied and the first +1. J] Due to aging and defects such as dust, foreign matter, and minute cracks in the thin film: Dielectric breakdown occurs in areas with low breakdown voltage.

At this time, peeling of the thin film does not occur. After that, ・iFi
Medical protection such as fat, etc. shines at 41% under moisture-proof conditions. This protective film has been destroyed (and the moisture-proofing treatment has now been completed).

Since the resulting EL panel undergoes initial aging at a voltage of VB, dielectric breakdown when used at a voltage of ■ is prevented, and therefore the EL panel is maintained at a voltage of VB. There is no risk of damage or damage, and as a result the panel is protected from moisture.

Effects of the Invention As is clear from the above description, the present invention eliminates the peeling of the thin film and D during the initial aging before forming the protective film, and prevents the peeling of the protective film due to dielectric breakdown of the thin film during the initial aging. Since heavy hot water is also prevented, a practical moisture-proof protective film type τ'!1lliMoEI, device G is provided.

[Brief explanation of the drawing]

Fig. 1 is a single tongue view of a thin film IAL panel, Fig. 2 (J, foil folding point number and luminescent layer of a thin film EL panel regarding applied 1S river, graph of 1x %'EE3 Fig. tj lament E], Pabane's aging M end saka installation type/>1 oblique 7 child [bad,
FIG. 4 is a schematic cross-section C of the aging device. 1...Glass plate, 2...Transparent electrode, 6.5.
...Insulating layer, 4...Light emitting layer, 6...Electrode, 7.
...Moisture-proof protection, 8...Insulation'gl broken part, 10.
it... Short circuit plate, 17... α source for pulse drive, 2
1... Heater. Patent IB Junjin Gaku Jutsu Co., Ltd. Patent attorney 1 patent attorney Izu Ki Akira Patent attorney Kazuyuki Nishidate Patent attorney 1) Yuki Onoben 1st person Akira Yamaguchi Figure 1 Figure 2 VA Vs Voltage Figure 3 Figure 4

Claims (1)

[Claims] A thin film Ef comprising a light emitting layer sandwiched between two electrodes on an insulating substrate, and a moisture-proof protective film provided thereon. When manufacturing (electroluminescence) equipment,
Prior to providing the protective film, the water vapor partial pressure is 10-3.
A method for manufacturing a thin film EL device, characterized in that initial aging is performed in an atmosphere of Torr or less by applying a voltage as high as the voltage required to obtain display brightness to the 2' electrode.