JPS62126506A - Transparent conductive film modification method - 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 [Field of Application of the Invention] The present invention relates to a method for modifying a thin film, and particularly relates to a method for modifying a transparent conductive film.

[Background of the invention]

Transparent conductive films are widely used in photoelectric conversion elements, liquid crystal displays, and the like. Materials currently commonly used include:
There are SnO2 and ITO (Sn added to In2O5), and SnO2 has the advantage of being chemically stable, and ITO has high conductivity. Due to its properties, transparent conductive films must have high light transmittance and high conductivity, and a number of manufacturing methods have been devised. Spray method (
Example G Paragraph Report as A27.197 (1982)
) has a low process cost, but has problems with uniformity.

CV D(Shemic(ZI Vαpar Depo
sltlon) method (e.g. Th1n 5o
11cl Films, 29.155 (1975)
) cannot be said to be a very common method because the raw material gas is limited. Vacuum evaporation method (e.g.,
ums.

70.910 (1980)), ionized vapor deposition methods (e.g. Th1n 5 solid pilins, L!
, 463 (1980)), sputtering method (Th1n
5olid Films, 8j4375 (19
81) ) etc. have been generally studied, and by optimizing conditions such as gas pressure and substrate temperature, conductivity of 1 to . 5X
A transparent conductive film of 10'Ω-'crR' and a light transmittance of 80 to 90% has been obtained. However, in order to improve the characteristics of devices such as photoelectric conversion elements, higher conductivity is required.

[Purpose of the invention]

The present invention was made in view of the above-mentioned drawbacks, and an object of the present invention is to provide a method of increasing electrical conductivity without reducing light transmittance.

[Summary of the invention]

The present inventors used vacuum evaporation method and ionization evaporation method.

We have discovered that by irradiating excimer laser light onto a transparent conductive film obtained by a sparing method or the like, it is possible to improve the conductivity of the conductive film without reducing its light transmittance. The laser energy density of the excimer laser light to be irradiated depends on the laser wavelength, the thickness of the transparent conductive film, the type of substrate, etc., but is suitably about 0.01 V2 to 0.5', 72.

LM (m) When examining the change in conductivity of a transparent conductive film when the laser energy density is changed, it is observed that the conductivity increases at an energy density lower than a certain value, and the conductivity decreases at an energy density higher than a certain value. In the present invention, the threshold laser energy density depends on the laser wavelength, the film thickness of the conductive film, the type of substrate, etc., and irradiation with an energy density lower than this value It is characterized by being modified by.

The atmosphere during irradiation is air or vacuum.

Either inert gas or oxygen may be used.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described by way of example embodiments.

[Example 1] A 5N02 film 2 formed by vacuum evaporation on a glass substrate (1 in FIG. 1) is irradiated with excimer laser light a as shown in FIG. Excimer laser light is ArF, KrF
, XeF, and XeCt were used. Laser energy density and conductivity when each laser number is irradiated.

Table 1 shows the relationship between changes in light transmittance. In either case, an improvement in electrical conductivity was observed without a decrease in light transmittance.

[Example 2] As shown in FIG. 1, an excimer laser beam a was applied to an ITO film 2 formed by vacuum evaporation on a glass substrate (1 in FIG. 1).
As in Example 1, four types of 0 excimer laser beams were used for irradiating.

Laser energy density and conductivity in each case,
Table 2 shows the relationship between changes in light transmittance. In either case, an improvement in electrical conductivity was observed without a decrease in light transmittance.

[Example 3] An ITO film 3 is formed on a glass substrate (1 in Fig. 2) by a vacuum evaporation method, and a SnO2 film 4 is further formed by a vacuum evaporation method.Excimer laser Jali irradiation is performed as shown in Fig. 2. Four types of zero energy laser beams were used as in Example 1.2.

Laser energy density and conductivity in each case,
Table 3 shows the relationship between changes in light transmittance. In either case, an improvement in electrical conductivity was observed without a decrease in light transmittance.

[Example 4] Even if the glass substrate used in Examples 1 to 5 was replaced with a synthetic quartz substrate and the excimer laser beam a was irradiated from the quartz side as shown in Figure @3, the same results as in Examples 1 to 3 were obtained. Good results were obtained with a margin of 0 or less [Effects of the Invention] According to the present invention, the conductivity of the transparent conductive film can be improved without reducing the light transmittance, thereby improving the characteristics of devices such as photoelectric conversion elements. It has the effect of increasing

[Brief explanation of drawings]

FIG. 1, FIG. 2, and FIG. 3 are explanatory diagrams showing embodiments of the present invention. 1...Glass substrate 3...ITO film 4...SnO2 film 5...Synthetic quartz substrate a...Excimer laser light No. 1 Funai 2 Hatakego Mozuguchi

Claims (1)

[Claims] 1. A method for modifying a transparent conductive film, which comprises modifying the transparent conductive film by irradiating the transparent conductive film with excimer laser light.