Highly conductive nanometer-thick gold films grown on molybdenum disulfide surfaces for interconnect applications

Thin gold (Au) films (10 nm) are deposited on different substrates by using a e-beam deposition system. Compared with sapphire and SiO2 surfaces, longer migration length of the Au adatoms is observed on MoS2 surfaces, which helps in the formation of a single-crystal Au film on the MoS2 surface at 200 degrees C. The results have demonstrated that with the assistance of van der Waals epitaxy growth mode, single-crystal 3D metals can be grown on 2D material surfaces. With the improved crystalline quality and less significant Au grain coalescence on MoS2 surfaces, sheet resistance 2.9 Omega/sq is obtained for the thin 10 nm Au film at 100 degrees C, which is the lowest value reported in literature. The highly conductive thin metal film is advantageous for the application of backend interconnects for the electronic devices with reduced line widths.