Abstract: a composite dielectric thin film capable of high dielectric constant, low leakage current characteristics, and high dielectric breakdown voltage while being deposited at a room temperature, a capacitor and a field effect transistor (FET) using the same, and their fabrication methods. The composite dielectric thin film is deposited at a room temperature or less than 200° C. and comprises crystalline or amorphous insulating filler uniformly distributed within an amorphous dielectric matrix or within an amorphous and partially nanocrystalline dielectric matrix.

Abstract: A method for fabricating an ultra-sensitive metal oxide gas sensor is disclosed, which comprises the steps of spinning a mixture solution including a metal oxide precursor and a polymer onto a sensor electrode to form a metal oxide precursor-polymer composite fiber; thermally compressing or thermally pressurizing the composite fiber; and thermally treating the thermally compressed or thermally pressurized composite fiber to remove the polymer from the composite fiber. Since the gas sensor includes a macro pore between nanofibers and a meso pore between nano-rods and/or nano-grains, gas diffusion and surface area can be maximized. Also, the ultra-sensitive sensor having high stability in view of mechanical, thermal, and electrical aspects can be obtained through rapid increase of adhesion between the metal oxide thin layer and the sensor electrode.