
Thin-film photovoltaics (TFPV) is being developed as a cheaper alternative to silicon-based wafers. There are three major types of thin-film photovoltaics, named according to the composition of their effective layers: silicon thin-film, II-VI (mainly cadmium antimonide), and CIGS(gallium selenide copper). Each effective layer film is used on a transparent conductive oxide film, and the substrate can be glass or metal.

Measure the effective layer
It is very important to accurately understand the thickness and composition of the effective layer. If it is too thin, it will affect efficacy and durability, while if it is too thick, it will increase costs. Incorrect composition can significantly reduce the efficacy and manufacturing output of the product.
The FilmetricsF20 model is used by dozens of thin-film photovoltaic manufacturers to measure the thickness and optical constants of three types of effective layers. To measure the effective layer films on transparent conductive oxide films, Filmetrics has gained extensive experience in testing single-layer and multi-layer conductive glass produced by users themselves or provided by professional glass manufacturers.
Other process films
In addition to the effective layer and the transparent conductive oxide stack, there are other films used in the manufacturing of photovoltaic products. These examples include polyimide and photoresist used for etching batteries and electrodes, as well as anti-reflection coatings. In these cases, Filmetrics has existing desktop, mapping, or online solutions.

Measurement example
Rapid and reliable measurement of multilayer films is the key to the development and manufacture of thin-film solar cells. In this case, we need to measure the thickness of the buffer layer (cadmium sulfide) and the absorption layer (cadmium telluride) on the thin-film photovoltaic. The F20-NIR combined with the collimated beam platform enables us to measure the thickness of cadmium telluride and cadmium sulfide layers on TEC glass from reflection spectroscopy.
Measurement setting

F20-NIR collimated beam fiber