High-κ Samarium-Based Metal–Organic Framework for Gate Dielectric Applications

The self-assembly of a samarium-based metal–organic framework [Sm 2 (bhc)(H 2 O) 6 ] n ( 1 ) in good yield was achieved by reacting Sm(NO 3 ) 3 ·6H 2 O with benzenehexacarboxylic acid (bhc) in a mixture of H 2 O–EtOH under hydrothermal conditions. A structural analysis showed that compound 1 crystallized in a space group of Pnmn and adopted a 3D structure with (4,8) connected nets. Temperature dependent dielectric measurements showed that compound 1 behaves as a high dielectric material with a high dielectric constant (κ = 45.1) at 5 kHz and 310 K, which is comparable to the values for some of the most commonly available dielectric inorganic metal oxides such as Sm 2 O 3, Ta 2 O 5, HfO 2, and ZrO 2 . In addition, electrical measurements of 1 revealed an electrical conductivity of about 2.15 × 10 –7 S/cm at a frequency of 5 kHz with a low leakage current ( I leakage = 8.13 × 10 –12 Amm –2 ). Dielectric investigations of the Sm-based MOF provide an effective path for the development of high dielectric materials in the future.