  A Seebeck coefficient measurement apparatus has been designed and developed,
which is very effective for accurate characterization of different type of
samples in a wide temperature range (80 - 650K) simultaneously covering low as
well as the high-temperature regime. Reducing the complexity of the technical
design of sample holder and data collections has always been challenging to
implement in a single instrument when samples are in different geometrical
shape and electronic structure. Our unique design of sample holder with
pressure probes covers measurements of different samples shapes (wires, thin
films and pellets) as well as different resistivity ranges (metals,
semiconductors and insulators). It is suitable for characterization of
different samples sizes (3-12 mm). A double heater configuration powered by a
dual channel source meter is employed for maintaining a desired constant
temperature difference across the sample for the whole temperature range. Two
K-type thermocouples are used for simultaneously reading of temperatures and
Seebeck voltages by utilizing different channels of a multichannel digital
multimeter. Calibration of the system has been carried out using constantan,
chromel and alumel materials and recorded data is found to be very accurate and
consistent with earlier reports. The Seebeck coefficients of standard samples
of constantan (wire) and GaN (thin film) have been reported, which shows the
measurement capability of designed setup with versatile samples.
