Coating Measurement of Solar Cells

Thickness and Refractive Index of Silicon Nitride

For wafer based solar cells the anti-reflective coating, surface passivation and diffusion barrier play an important role to achieve high solar cell efficiency and long term stability. Because of its excellent characteristics Silicon Nitride coating (a-SiNx:H) is widely used for this purpose. Process parameters like gas pressure and temperature of the cell during deposition have a strong influence on the layer thickness, colour and the optical constants n&k of Silicon Nitride. Traditionally it takes time and skills to obtain a precise coating distribution map to enable process optimization.

Using industry-proven spectrometer technology and proprietary measurement algorithms, Helios SCAN-tn combines speed, precise measurement and easy operation – all of which are needed to optimize processes at lowest cost and shortest line downtime.

 

Helios SCAN-tn is a fully automatic measurement system that enables you to create coating distribution maps for the layer thickness as well as the refractive index of the coated wafer within less than one minute!

• Layer thickness √
• Refractive index √
• Automatic XY positioning table √
• Pre-configured mapping templates √
• Automatic calibration √
• Automatic coating distribution plots √
• Single-point measurement √