Thermal properties of high-k Hf_(1-x)Si_xO_2  

作　　者：司凤娟 路文江 汤富领 

机构地区：[1]State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials,Department of Materials Science and Engineering,Lanzhou University of Technology [2]Key Laboratory of Non-ferrous Metal Alloys and Processing of Ministry of Education,Lanzhou University of Technology

出　　处：《Chinese Physics B》2012年第7期431-438,共8页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 10964003 and 11164014);the Natural Science Foundation of Gansu Province, China (Grant No. 096RJZA102);the Specialized Research Fund for the Doctoral Program of Higher Education, China (Grant No. 20096201120002);the China Postdoctoral Science Foundation (Grant Nos. 20100470886 and 201104324)

摘　　要：Classical atomistic simulations based on the lattice dynalnics theory and the Born core-shell model are performed to systematically study the crystal structure and thermal properties of high-k Hfl-xSixO2. The coefficients of thermal expansion, specific heat, Griineisen parameters, phonon densities of states and Debye temperatures are calculated at different temperatures and for different Si-doping concentrations. With the increase of the Si-doping concentration, the lattice constant decreases. At the same time, both the coefficient of thermal expansion and the specific heat at a constant volume of Hf1-mSixO2 also decreases. The Griineisen parameter is about 0.95 at temperatures less than 100 K. Compared with Si-doped HfO2, pure HfO2 has a higher Debye temperature when the temperature is less than 25 K, while it has lower Debye temperature when the temperature is higher than 50 K. Some simulation results fit well with the experimental data. We expect that our results will be helpful for understanding the local lattice structure and thermal properties of Hf1-mSixO2.Classical atomistic simulations based on the lattice dynalnics theory and the Born core-shell model are performed to systematically study the crystal structure and thermal properties of high-k Hfl-xSixO2. The coefficients of thermal expansion, specific heat, Griineisen parameters, phonon densities of states and Debye temperatures are calculated at different temperatures and for different Si-doping concentrations. With the increase of the Si-doping concentration, the lattice constant decreases. At the same time, both the coefficient of thermal expansion and the specific heat at a constant volume of Hf1-mSixO2 also decreases. The Griineisen parameter is about 0.95 at temperatures less than 100 K. Compared with Si-doped HfO2, pure HfO2 has a higher Debye temperature when the temperature is less than 25 K, while it has lower Debye temperature when the temperature is higher than 50 K. Some simulation results fit well with the experimental data. We expect that our results will be helpful for understanding the local lattice structure and thermal properties of Hf1-mSixO2.

关 键 词：thermal properties lattice structure high-k material 

分 类 号：O482.2[理学—固体物理]