Zhao Dehe, Gao Wei, Li Yujing, Zhang Yuyuan, Yin Hong
State Key Laboratory of Superhard Materials, College of Physics, Jilin University No. 2699 Qianjin Street Changchun 130012 People's Republic of China
RSC Adv. 2019 Mar 14;9(15):8435-8443. doi: 10.1039/c9ra00784a. eCollection 2019 Mar 12.
Clarifying the electronic states and structures of the c-BN/diamond interface is of extreme importance for bundling these two different wide-band gap materials in order to synthesize hybrid structures with new functional properties. In this work, the structural optimization and property determinations were carried out on (100) and (111) c-BN/diamond hetero-interface by using first principles total energy calculations. A 12-layers c-BN above the diamond was found to be energetically reasonable for the calculations of the properties of the hetero-interface. Based on the calculation of the chemical potentials for the c-BN/diamond interface, the hetero-interface with the C-B configuration is the most energetically favorable structure under the (111) and (100) surfaces of diamond, respectively. The calculations of band structure and density of states for C-N bond configuration indicate that the main contribution to the density of the interface states near the is from the N 2s 2p, B 2p and C 2p orbitals while that for C-B bond configuration is mainly from the B 2p, N 2p and C 2p orbitals. The electron density difference, binding energy and band offset were also calculated, demonstrating that the C-B bond was found to be remarkably stronger than other adjacent bonds. Furthermore, a band offset of 0.587 eV for the (111) c-BN/diamond hetero-interface with the C-N bond configuration has been obtained, which is in good agreement with the previous experimental result (0.8 eV), suggestting that the C-N bond may exist in synthesized c-BN/diamond epitaxy using different growth methods. This should allow the design of a hybrid structure of c-BN/diamond thereby opening a new pathway towards high temperature electronics, UV photonics and (bio-) sensor applications.
阐明立方氮化硼（c-BN）/金刚石界面的电子态和结构对于将这两种不同的宽带隙材料结合起来以合成具有新功能特性的混合结构极为重要。在这项工作中，通过使用第一性原理总能量计算对（100）和（111）c-BN/金刚石异质界面进行了结构优化和性质测定。发现金刚石上方12层的c-BN对于异质界面性质的计算在能量上是合理的。基于对c-BN/金刚石界面化学势的计算，具有C-B构型的异质界面分别是金刚石（111）和（100）表面下能量最有利的结构。对C-N键构型的能带结构和态密度的计算表明，靠近费米能级的界面态密度的主要贡献来自N 2s 2p、B 2p和C 2p轨道，而对于C-B键构型，主要来自B 2p、N 2p和C 2p轨道。还计算了电子密度差、结合能和带隙偏移，结果表明C-B键明显比其他相邻键更强。此外，对于具有C-N键构型的（111）c-BN/金刚石异质界面，获得了0.587 eV的带隙偏移，这与先前的实验结果（0.8 eV）吻合良好，表明在使用不同生长方法合成的c-BN/金刚石外延中可能存在C-N键。这应该有助于设计c-BN/金刚石的混合结构，从而为高温电子学、紫外光子学和（生物）传感器应用开辟一条新途径。
