ELECTRICAL PROPERTIES OF TIN FILMS PREPARED BY PLASMA ASSISTED ATOMIC LAYER DEPOSITION USING TETRAKIS(DIMETHYLAMIDO)-TITANIUM

摘要

By using cyclic pulses of tetrakis-dimethylamido-titanium (TDMAT) and H_2 plasma, TiN_x thin films were grown at the deposition temperatures of 175℃ to investigate the effects of process conditions on the electrical properties of the TiN_x films. The use of longer pulses and higher power improved the electrical properties, lowered the resistivity and increased the stability in air, of the TiN_x films. The film growth rate (thickness/cycle) was in the range of 0.07 - 0.09 nm/cycle and the resistivity of the films varied from ～ 250 to 30000 μΩcm, depending on the plasma conditions. Barrier performance of the TiN_x films to copper diffusion in the Cu/ TiNx/Si structure was evaluated by the Seccon-etch test, and no evidence of copper diffusion was observed even after annealing for an hour at 550℃.