{"content":[{"text":"thermal conductivity with increasing amount of Al was observed and increasing \n scattering of phonons on alloying element atoms is responsible for such behavior.","bbox":{"left":0.118954,"top":0.082217,"width":0.693753,"height":0.04399299999999999}},{"text":"role of","bbox":{"left":0.822763,"top":0.082217,"width":0.060640999999999945,"height":0.019196000000000005}},{"text":"In-plane and cross-plane thermal conductivities of AlxGa1-xN/GaN (x � 0.225, 0.240, 0.250, \n 0.280) superlattices with the period thicknesses (which is equal to sum of the thickness of \n AlGaN and GaN layers) ranging from 44.6 nm to 4.8 nm was measured from 147 K to 325 K. \n Opposite temperature dependencies of thermal conductivity were observed - in-plane thermal \n conductivity decreased, while cross-plane -increased with increasing temperature. Superlattice \n thermal conductivity was calculated with the use of Callaway model; frequency dependence of \n phonon-boundary relaxation time was taken into account. Results of calculations shown, that \n long-wavelength phonons are the dominant heat carriers. Decrease of thermal conductivities \n with decreasing period thickness was observed. Scattering of the phonons on the layer \n boundaries leads to this thermal conductivity dependence on period thickness, moreover, \n influence of this scattering increases with reduction of the layer thickness.","bbox":{"left":0.118638,"top":0.140801,"width":0.7648529999999999,"height":0.265441}},{"text":"2","bbox":{"left":0.872447,"top":0.92583,"width":0.008461000000000052,"height":0.016591000000000022}}],"images_bbox":[],"images_bbox_not_text_overlap":[]}