ABSTRACTSCANNING PROBE MEASUREMENT SYSTEM FOR ROOM TEMPERATURE THERMOPOWER By Marvell Mukongolo The development of new and established materials for use in thermoelectric devices, and the development of new measurement techniques for the advancement of research in the field are major initiatives of thermoelectrics research at Michigan State University. To achieve this, measurement systems created for this research have to be accurate and as well as diverse in their capabilities. A new measurement system with scanning probe capabilities has been developed to measure thermopower at room temperature. The degree of homogeneity of bulk thermoelectrical materials can be obtained with thermopower measurements due to the fact that the thermopower of a semiconductor is related to the concentration of impurities in the material. Devices made of inhomogeneous or segmented materials are known to have increased efficiency compared to devices with homogeneous composition. The ability to characterize in-homogeneity in devices adds a new dimension to the type of research that can be achieved. This thesis presents an introduction to the room temperature thermopower scanning probe. The system is designed to operate in an open air, room temperature environment. The system is fully automated with LabVIEW software used for control and data collection purposes. Reference materials were used to verify the systems accuracy. A study of segmented p-type materials composed of Bi2Te3-LASTT (Ag(Pb1-xSnx)mSbTe2+m) and n-type materials composed of Bi2Te3-LAST (AgPbmSbTe2+m) is also be presented.
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