Tuning properties of SnO 2 /Au/SnO 2 multilayer with variable Au thicknesses as transparent conductive oxides

Multilayer tin oxide/gold/tin oxide (SnO 2 /Au/SnO 2 ) was deposited by atomic layer deposition and an e-beam evaporator. The structural, electrical, and optical properties of the SnO 2 /Au/SnO 2 multilayer were investigated. Au formed islands at a thickness less than 3 nm. As the Au interlayer thickness increased, the Au islands merged, resulting in a continuous film 12 nm thick. As the Au interlayer thickness increased from 0 to 12 nm, the carrier concentration and Hall mobility increased to 2.41 × 10 22 cm −3 and 11.96 cm 2 V −1 s −1 , respectively. As a result, the resistivity decreased at 10 −5 Ω cm with an increasing Au interlayer thickness compared to a SnO 2 single layer. In addition, optical transmittance at 550 nm increased by more than 80% at 6 and 9 nm than at Au thicknesses of 3 and 12 nm. SnO 2 /Au/SnO 2 multilayers are promising candidates as an indium-free transparent conducting oxide for use in high performance optoelectronic devices.