MARC 主機 00000nam  2200349   4500 
001    AAI3301341 
005    20081125145804.5 
008    081125s2008    ||||||||||||||||| ||eng d 
020    9780549465355 
035    (UMI)AAI3301341 
040    UMI|cUMI 
100 1  Singh, Rajeev 
245 10 Experimental characterization of thin film thermoelectric 
       materials and film deposition via molecular beam epitaxy 
300    158 p 
500    Source: Dissertation Abstracts International, Volume: 69-
       02, Section: B, page: 1226 
500    Adviser: Ali Shakouri 
502    Thesis (Ph.D.)--University of California, Santa Cruz, 2008
520    Due to the control and precision of deposition afforded by
       molecular beam epitaxy (MBE), it is a good choke for the 
       deposition of thin-film thermoelectric materials in a 
       research environment. The high resolution of source 
       element flux rate permits materials of precise bandgap 
       energies and carrier concentrations to be deposited. The 
       low growth rates possible with MBE permit the deposition 
       of materials containing high quality features at the 
       nanometer scale. In addition, the ultra-clean environment 
       characteristic of MBE can foster the growth of materials 
       with exceptionally low background impurity concentrations 
       and consequently high carrier mobilities. Although the 
       technology of MBE can be a useful tool for epitaxial 
       growth of thin films the science of ultra-high vacuum 
       (UHV) can be enigmatic. Some key practical elements of UHV
       science will be presented and discussed to aid the MBE 
       user in successful growth of high-quality materials. The 
       equipment and methods used to characterize growth and 
       material parameters as well as vacuum chamber integrity 
       will be explored. Various calibration techniques of the 
       growth system will be outlined. The deposition of III-V 
       arsenide materials containing erbium arsenide 
       nanoparticles will be briefly highlighted. Finally, 
       thermoelectric materials and devices will be characterized
       using various techniques. Thermoreflectance is utilized at
       wavelengths in the near-infrared (NIR) regime to image the
       temperature distribution on the contacts of a thin-film 
       thermoelectric module non-destructively through the 
       module's silicon substrate 
520    A novel thin-film thermoelectric material composed of semi
       -metallic ErAs nanoparticles embedded in an InGaAlAs 
       semiconductor matrix (ErAs:InGaAlAs) is studied in this 
       work. The MBE-grown material is designed for enhanced 
       thermoelectric figure-of-merit (ZT) at temperatures in the
       range of 600 K to 900 K. Samples are designed and 
       fabricated for accurate measurement of the thermoelectric 
       properties of ErAs:InGaAlAs thin films 
520    Devices designed and fabricated for direct cross-plane ZT 
       measurement of ErAs:InGaAlAs material using the transient 
       Harman method are characterized and analyzed at room 
       temperature in order to determine the measurement accuracy
       obtained from the devices 
520    A novel thermostat is designed and fabricated to measure 
       thermoelectric material and device properties from room 
       temperature to 850 K. The thermostat is capable of 
       measuring thin-film material in-plane Seebeck coefficient 
       and electrical conductivity as well as the cross-plane ZT 
       of thin-film devices 
520    State-of-the-art n-type (In0.530Ga0.376 
       Al0.094As)0.997ErAs0.003 thermoelectric material designed 
       for power generation at high temperatures is characterized
       over a wide temperature range using the custom thermostat.
       (Abstract shortened by UMI.) 
590    School code: 0036 
590    DDC 
650  4 Engineering, Electronics and Electrical 
690    0544 
710 2  University of California, Santa Cruz 
773 0  |tDissertation Abstracts International|g69-02B 
856 40 |u