脉冲时间参数对电沉积铜薄膜性能的影响

Effects of Pulse Time Parameters on the Properties of Electrodeposited Copper Film

针对先进纳米铜互连技术的要求,研究了脉冲时间和关断时间对铜互连薄膜电阻率、晶粒尺寸和表面粗糙度等性能的影响。实验结果表明,占空比较小时,镀层电阻率较大,晶粒直径较小。脉冲时间选择在毫秒数量级,占空比选择在40%～60%之间容易获得较小电阻率和较大晶粒尺寸的铜薄膜。

Aiming at the technology demand of advanced copper interconnect, the effects of pulse on-time and pulse off-time on Copper film properties such as resistivity, grain size and surface roughness were investigated. The results showed that when duty cycle was smaller, the resistivity of Cu film was bigger and the crystal size was smaller. The level of pulse on-time and off-time should both be chosen at millisecond scale. When duty cycle was 40% to 60%, lower resistivity and bigger crystal size of Cu film would be easily obtained.