Accurate and repeatable recording of the thermal profile during the metallization process is very important to produce silicon solar cells with the best physical and electrical properties. Traditional thermocouple and attachment procedures include a 0.02 sheath, spherical bead type K thermocouple cemented on the reference wafer, and spring loaded (weighted) on wafer.
In this paper, Casey will discuss a procedure using a thermal profiler and flattened TC junction thermocouples in a wafer fixture for accurate and repeatable measurements in an IR belt furnace.
When using the SunKIC Datalogger and e-Clipse TC attachment fixture, the TC junction design can identify the aluminum melting temperature and alloy eutectic freezing temperature. In addition, the actual production wafers can be profiled and the surface temperature is recorded at four locations.