The conducting tin oxide thin films deposited via atomic layer deposition using Tetrakis-dimethylamino tin and peroxide for transparent flexible electronics

Abstract

The ALD SnO2 thin films were investigated as a function of growth temperature to obtain optimized process and film properties using tetrakis(dimethylamino)tin as a Sn precursor, and hydrogen peroxide as reactant. The film growth shows 1.2 angstrom/cycle in the 100-200 degrees C temperature range and follows typical ALD window behavior. ALD SnO2 thin films show low resistivity (9.7 x 10(-4) Omega cm) at 200 degrees C, and high carrier mobility (22 cm(2)/V sec). The transmittance of 40 nm ALD SnO2 films was over 80% at all of temperatures. The growth behavior, film composition, chemical bonding states, film crystallinity, electronic structure, and optical properties were investigated in order to verify the origin of the electrical properties as a function of growth temperature. These data show that the favorable properties of ALD SnO2 are due to the electronic band structure change associated with poly-crystalline formation.