company news about How can vacuum coatings be made non-conductive

Vacuum coating coating is not completely non-conductive, non-conductive is to take advantage of the molecular discontinuity in the film state
Metals or metal compounds all have the ability to conduct electricity, but the conductivity is different. However, when a metal or metal compound is in a thin film state, its corresponding physical properties will be different.

In conventional coating materials, such as: silver is the silver effect and the best conductive metal, but when its thickness is below 5 nanometers, it is non-conductive; The silver effect and conductivity of aluminum are slightly worse than that of silver, but it is already conductive when it is 0.9 nanometers thick.

Why is this?

That's because the continuity of silver molecules is not as good as that of aluminum, so at relative film thickness, its conductivity is poor. Our vacuum gold-plated non-conductive film actually uses the principle of poor molecular continuity of some metals to control its thickness within a certain range, so that it has a silver-white appearance and large resistance.

It can be seen that the effect of the metal non-conductive film is directly related to its film thickness. Only under the corresponding film thickness, the corresponding stable silver-white non-conductive film can be obtained.

It has been mentioned above that the silver white effect and the best conductive performance of silver in the thickness of less than 5 nanometers, it is non-conductive, then, can we use silver to do the metal non-conductive film we need?

The answer is no.

Because the thickness of silver below 5 nanometers is basically transparent and colorless, although it is not conductive, it cannot have the effect of silver reflective film at the same time. Similarly, aluminum does not work.

Therefore, we need a kind of metal material that can be plated with a silver-white metallic luster and has a large resistance. We use tin or indium and indium tin alloy with purity above 99.99%. The thickness of the tin below 30 nm, continuity is quite poor, but can obtain a silver-white metallic luster and has a large resistance. Indium is the same, but indium's silver-white reflectivity is better than the appearance of tin, because the price is higher, we use indium-tin alloy, so that we can get a non-conductive film and get a whiter and brighter reflective metal effect!