The Research Of Characterization And Properties Of GaN Based Thermoelectric Materials

Thermoelectric material is a very widely used semiconductor functional materials, it can achieve mutual conversion between heat and electricity. GaN-based thermoelectric material having a larger band gap and good thermal stability and high electrical conductivity and Seebeck(Seebeek) coefficient, so these materials has become a very promising thermoelectric materials.In this paper, GaN-based thermoelectric materials for the study, to build a semiconductor material at room temperature measured Seebeck coefficient and electrical conductivity of the device. In addition, the equipment to achieve automatic control, using the control program is based on Labview software platform for measurement and control, using a graphical editor G programming language. This device is used to measure the semiconductor thin film material Seebeck coefficient and electrical conductivity, Seebeck coefficient and electrical resistivity are important thermoelectric materials transport performance parameters. Accurate determination of their transport mechanism for in-depth study of thermoelectric semiconductor materials, especially those with a very important application value and theoretical significance for further research and development of new semiconductor thermoelectric materials and devices.Thermoelectric properties of GaN materials at room temperature were studied. The results showed that with the increase of the carrier concentration decreases mobility, conductivity increases, the Seebeck coefficient decreases, the range between 100-500μV/ K. The carrier concentration of 1.60×1018cm-3, the thermoelectric power factor GaN thin film material have a maximum value of 4.72×10-4W/mK2, ZT GaN film temperature reaches a maximum value of 0.0025. In addition, the large pieces of material and thermoelectric properties of GaN thin film GaN materials were compared, the results show that the films GaN materials have higher dislocation scattering, the Seebeck coefficient than the large chunks of GaN materials. Since the Seebeck coefficient of bulk GaN material is relatively low, so its power factor in the range of between 0.315×10-4 W/mK2 to 0.354×10-4 W/mK2.A brief introduction about production methods and the prospects for its GaN devices for further study.