A highly stable silicon nitride deposition process is paramount for high cell efficiency as well as the consistent cosmetic appearance of the solar cells in your modules. 100% Inline measurement of the SiNx thickness and refractive index provides you with essential capabilities to achieve the maximum out of your coater and deposition process.
Measurement directly on textured wafers helps to avoid preparation of special polished wafers. Apart from lower labor expenses, measuring directly on the real production wafers has an additional benefit: the indirect correlation between the measurement on polished reference wafers and the actual textured production wafers becomes obsolete.
Higher line up time is another important capability that is obtained. Access to thickness and refractive index trends of every produced wafer will enable you to make optimum use of your plasma or sputtering targets. After periodic coater cleaning and maintenance you will be able to reach your process window more quickly as the required control readings are available directly after the first coated wafer. On an annual basis, this time gain will allow you to produce considerably more wafers.
More A-grade cells are the result of smaller process deviations, which subsequently cause consistent efficiency and equal cosmetic solar cell appearance.