Method of making thermally tempered coated article with transparent conductive oxide (TCO) coating and product made using same

Abstract

A method of making a coated article including a transparent conductive oxide (TCO) film supported by a tempered glass substrate is provided. Initially, an amorphous metal oxide film is sputter-deposited onto a non-tempered glass substrate, either directly or indirectly. The glass substrate with the amorphous film thereon is then thermally tempered using high temperatures. The thermal tempering causes the amorphous film to be transformed into a crystalline transparent conductive oxide (TCO) film. The heat used in the thermal tempering of the glass substrate causes the amorphous film to turn into a crystalline film, causes the visible transmission of the film to increase, and / or causes the film to become electrically conductive.

Description

[0001] This invention relates to a method of making a thermally tempered coated article including a transparent conductive oxide (TCO) film supported by a tempered glass substrate. A coated article, that is thermally tempered and made by such a process, is also provided. Coated articles according to certain example non-limiting embodiments of this invention may be used in applications such as solar cells, oven doors, defrosting windows, or other types of windows in certain example instances. BACKGROUND AND SUMMARY OF EXAMPLE EMBODIMENTS OF INVENTION [0002] Typically, methods of forming TCOs on glass substrates require high glass substrate temperatures. Such methods include chemical pyrolysis where precursors are sprayed onto the glass substrate at approximately 400 to 500 degrees C., and vacuum deposition where the glass substrate is kept at about 150 to 300 degrees C. Unfortunately, TCO films such as SnO2:F (fluorine doped tin oxide) formed on glass substrates by chemical pyrolysis...

AI Technical Summary

Benefits of technology

[0006] Thus, it will be appreciated that there exists a need in the art for an improved technique or method of tempering glass substra

Problems solved by technology

Such methods include chemical pyrolysis where precursors are sprayed onto the glass substrate at approximately 400 to 500 degrees C., and vacuum deposition where the glass substrate is kept at about 150 to 300 degrees C. Unfortunately, TCO films such as SnO2:F (fluorine doped tin oxide) formed on glass substrates by chemical pyrolysis suffer from non-uniformity and thus may be unpredictable and / or inconsistent with respect to certain optical and / or electrical properties.

Unfortunately, it has been found that glass substrates supporting sputter-deposited TCOs cannot be thermally tempered without the TCOs suffering a significant loss in electrical conductivity.

If the Sb content is higher than this, the lattice is disturbed too much and mobility of electrons is also disturbed thereby hurting conductivity of the film, whereas if less than this amount of Sb is provided then the conductivity is not as good in the crystalline film.

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