Fabrication of TiO2/Cu hybrid composite films with near zero TCR and high adhesive strength via aerosol deposition

Abstract Room-temperature fabrication of TiO 2 /Cu composite films for embedded passive components were attempted via aerosol deposition process. XRD analysis and observation of internal microstructures revealed that TiO 2 /Cu composite films using 500 nm-sized TiO 2 had further tight bonding between particles compared to 25 nm-sized TiO 2 , due to effect of initial TiO 2 particle size on densification of internal microstructures. Then, to optimize their adhesive strength and temperature coefficient of resistance (TCR), electrical and mechanical properties of TiO 2 (500 nm)/Cu composite films with different content of TiO 2 were evaluated for applications as advanced composite film resistors. Results showed that TiO 2 /Cu (50 wt%/50 wt%) composite films had sufficient electrical resistivity (5.8 ×10 −3 Ω cm), excellent near-zero TCR (−3 ppm/℃), and improved adhesive strength (~ 7.37 N/mm 2 ) resulting from proper coexistence of anchoring bonds and mechanical interlocking formed during deposition.