The thin film solder of each batch is controlled by a
melting test on samples from this batch. This test is
performed on a Linkam THMS600 heating stage with a
TMS94 programmable temperature controller. This
heating stage consists of a small silver block with
integrated heater and temperature sensor. The samples are
placed in a crucible on the silver block. The whole
arrangement is in a closed chamber. The temperature
profile is controlled very accurately with a time constant
in the range of one second. It is possible to calibrate this
setup, so that the temperature reading is close to the real
temperature on the sample surface. This is especially true,
if the same type of sample is consistently used.