Lee Miso, Youn Yong, Yim Kanghoon, Han Seungwu
Department of Materials Science and Engineering and Research Institute of Advanced Materials, Seoul National University, Seoul, 08826, Korea.
Korea Institute of Energy Research, Daejeon, 34129, Korea.
Sci Rep. 2018 Oct 4;8(1):14794. doi: 10.1038/s41598-018-33095-6.
High-k dielectrics, materials having a large band gap (E) and high dielectric constant (k) simultaneously, constitute critical components in microelectronic devices. Because of the inverse relationship between E and k, materials with large values in both properties are rare. Therefore, massive databases on E and k will be useful in identifying optimal high-k materials. While experimental and theoretical data on E and k of oxides are accumulating, corresponding information is scarce for non-oxide dielectrics with anions such as C, N, F, P, S, and Cl. To identify promising high-k dielectrics among these material groups, we screen 869 compounds of binary carbides, nitrides, sulfides, phosphides, chlorides, and fluorides, through automated ab initio calculations. Among these compounds, fluorides exhibit an E-k relation that is comparable to that of oxides. By further screening over ternary fluorides, we identify fluorides such as BiF, LaF, and BaBeF that could serve as useful high-k dielectrics.
高k电介质是同时具有大带隙（E）和高介电常数（k）的材料，是微电子器件中的关键组件。由于E和k之间存在反比关系，同时具备这两种特性的材料很少见。因此，关于E和k的大量数据库将有助于识别最佳的高k材料。虽然关于氧化物的E和k的实验和理论数据在不断积累，但对于含有C、N、F、P、S和Cl等阴离子的非氧化物电介质，相应的信息却很少。为了在这些材料类别中识别出有前景的高k电介质，我们通过自动从头算计算筛选了869种二元碳化物、氮化物、硫化物、磷化物、氯化物和氟化物。在这些化合物中，氟化物表现出与氧化物相当的E-k关系。通过对三元氟化物的进一步筛选，我们确定了BiF、LaF和BaBeF等氟化物可作为有用的高k电介质。
