Title :
Effect of dislocations on phonon drag thermopower in GaN/AlGaN heterojunctions
Author :
Kamatagi, M.D. ; Sankeshwar, N.S. ; Mulimani, B.G.
Author_Institution :
B.V.B. Coll. of Eng. & Technol., Hubli
Abstract :
The phonon drag contribution, Sg, to the thermopower in GaN/AlGaN heterojunctions is studied, for the first time, over the temperature range 2 < T < 100 K. The two-dimensional electrons are considered to interact via screened deformation and piezoelectric potentials, whereas the phonons are assumed to be scattered by sample boundaries, impurities, dislocations and other phonons. Numerical results for Sg are presented with the intrinsic phonon parameters obtained from thermal conductivity data. Sg is found to be of the order of a few mV/K. The effect of dislocations is not only to reduce Sg but also to modify its behaviour.
Keywords :
III-V semiconductors; aluminium compounds; dislocations; gallium compounds; semiconductor heterojunctions; thermal conductivity; two-dimensional electron gas; 2D electrons; GaN-AlGaN; deformation; dislocations; intrinsic phonon parameters; phonon drag thermopower; piezoelectric potentials; semiconductor heterojunctions; thermal conductivity; Acoustic scattering; Aluminum gallium nitride; Electrons; Gallium nitride; Heterojunctions; Phonons; Temperature; Thermal conductivity; Thermoelectric devices; Thermoelectricity; Gallium compounds; semiconductor heterojunctions; thermoelectricity;
Conference_Titel :
Physics of Semiconductor Devices, 2007. IWPSD 2007. International Workshop on
Conference_Location :
Mumbai
Print_ISBN :
978-1-4244-1728-5
Electronic_ISBN :
978-1-4244-1728-5
DOI :
10.1109/IWPSD.2007.4472545
