hi
How we can made temperature sensor using VAN DER PAUW structure ?
A Platinum thin-film element[1] can be used[2] as a Resistance (R) to temperature (T) sensor[1,2] in a VAN DER PAUW (VdP) topology[3] of the contacts/electrodes. The 4-contacts (and the VdP) resistance is more reliable[4], than the commonly used (only 2-contacts, Pt) resistance thermometers[2] and it is independent from the cable's length, also.
1. https://en.wikipedia.org/wiki/Resistance_thermometer
2. http://www.yokogawa.com/us/support/knowledgebase/what-is-the-difference-between-pt100-and-pt1000-temperature-sensor-and-which-one-is-better.htm
3. http://electron.mit.edu/~gsteele/vanderpauw/vanderpauw.pdf
4. The 4-contacts R is more reliable for many electrical, electronic, chemical and mechanical issues.
In addition to Dr. Samaras excellent recomendation I should notice that you also can use nonmetallic layers to perform a temperature sensor based on R(T) measurement, e.g., doped semiconductor layers or conductive oxides, depending on the your requirements on the functionality, if sensor should be integrated in certain system or planarly integrated in some ship.
Van-der Paw 4-contact geometry indeed provide an exclusion of contact resistance and possible nonideality of contact I-V characteristics, but the last could be though rather ohmic than refractive.
Also take care about possible сoncomitant thermoelectic voltage if a temperature gradient present in the sensor structure, in this case current direction reversal is useful to exclude it and obtain an intrinsic resistance.
Van der Pauw technique is a (four probe) method suitable for measuring resistivity (for flat samples). Resistivity can also be measured by a classical 2 probe or a four probe technique.
The 2 probe technique is only used when the resistance of the wires and the contact resistances are small compared to the resistance of the device.
When these parasitic resistances cannot be neglected, one uses a four probe technique, either the classical one or the VdP method.
It is then necessary to pass from the resistance to the resistivity. With the classical method you need the length and the (constant) section of the sample. With the VdP method you only need the thickness which must be constant.
VdP method is adapted for thin films, foils and more generally for flat samples. The classical four probe technique is adapted for long samples.
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