Deposition And Evaluation Of Self Assembled Monolayer As Diffusion Barrier For Copper Metallization For Integrated Circuits

Self Assembled Monolayer was deposited on silicon substrate using 3-aminopropyltrimethoxysilane (APTMS). The diffusion barrier properties of this layer against copper diffusion were studied. For this purpose, Cu/SiO2/Si and Cu/SAM/SiO2/Si structures were compared. The samples were annealed at various temperatures in vacuum ambient. The characterization was performed using X-Ray diffraction, Four Probe Resistivity measurement and Capacitance-Voltage technique. C-V measurement was performed by applying Bias Thermal Stress (BTS). XRD Results indicated that combination of SiO2/SAM worked as diffusion barrier layer up to 600 degrees C whereas SiO2 could work as barrier only up to 400 degrees C. C-V and resistivity plots also supported the possibility of using SAM as a good barrier for copper metallization in VLSI systems.