  We carefully investigated the transport and capacitance properties of few
layer charge density wave (CDW) 2H-TaS2 devices. The CDW transition temperature
and the threshold voltage vary from device to device, which is attributed to
the interlayer interaction and inhomogeneous local defects of these
micro-devices based on few layer 2H-TaS2 flakes. Semiconductivity rather than
metallic property of 2H-TaS2 devices was observed in our experiment at low
temperature. The temperature dependence of the relative threshold voltage can
be scaled to (1- T / Tr )^0.5+delta with delta=0.08 for the different measured
devices with presence of the CDWs. The conductance-voltage and capacity-voltage
measurements were performed simultaneously. At very low ac active voltage, we
found that the hysteresis loops of these two measurements exactly match each
other. Our results point out that the capacity-voltage measurements can also be
used to define the threshold depinning voltage of the CDW, which give us a new
method to investigate the CDWs.
