Synthesis and characteristics of solution processable organic-inorganic hybrid high-k materials for gate dielectric

Abstract

Solution-processable organic-inorganic hybrid materials were synthesized by the sol-gel method of photopatternable silane and transition metal alkoxides for thin film transistors (TFTs) at room temperature. Using a controlled chemical reactivity of metal alkoxides to hydrolysis and condensation, the synthesized hybrid materials had a high transmittance of over 90 % in the visible region. Addition of transition metal alkoxide was improved the dielectric constant compared with the conventional silicon oxide film (k ~ 3.9) and adjustment of Zr/Si molar ratios exhibited better dielectric constant from 4.2 to 4.7 at 1 MHz. The leakage current density reduced 5.5 $nA/cm^2$, by minimizing silanol groups into the synthesized hybrid materials. Consequently, hybrid materials with a high dielectric constant and low hydroxyl groups can be utilized as the gate dielectric in the TFTs.