扩散阻挡层对Cu-Zr纳米合金膜电阻率与残余应力的影响

EFFECT OF DIFFUSION BARRIERS ON PROPERTIES OF Cu-Zr ALLOY FILMS ON Si SUBSTRATE

用磁控溅射和离子束溅射共沉积的方法分别在以单晶硅为基体的TiN,TaN,ZrN扩散阻挡层上沉积了Cu-Zr合金膜,膜在400℃氮气中退火1h.结果表明扩散阻挡层对膜的晶体取向、电阻率和残余应力有很大影响.沉积态的膜具有强的（111）取向,且峰型严重展宽;退火后峰型明显锐化,出现（200）等晶体取向;对应TiN,TaN;ZrN三种扩散阻挡层,膜的电阻率在沉积态时分别达108,327和478μΩ·cm,退火后降至正常的数个μΩ·cm;扩散阻挡层亦可明显降低膜的残余应力,无扩散阻挡层时膜的退火应力达475MPa,有ZrN扩散阻挡层后退火应力降至149MPa.

Cu-Zr alloy films were deposited on different diffusion barriers(TiN, TaN, ZrN) with co-depositing technology combined magnetron sputtering (MS) and ion beam sputtering (IBS) together. The films were annealed at 400 degreesC for an hour in N-2. It was found that the diffusion barriers have strong effect on the crystal orientation, resistivity and residual stress of the alloy film. The as-deposited Cu-Zr alloy films have strong (111) texture and the (111) diffraction profiles were remarkably broaden. After annealing the (111) peaks of Cu-Zr alloy films became sharp and appeared apparently (200) orientation. The resistivities of Cu-Zr alloy film were 108, 327 and 478 muOmega(.)cm respectively when TiN, TaN and ZrN were acted as diffusion barriers, and eventually decreased to normal values of several muOmega(.)cm after annealing. The diffusion barriers could obviously decrease the residual stress of Cu-Zr alloy films. The stress value without diffusion barriers was up to 4.75 MPa but decreases down to 149 MPa with the diffusion barrier of ZrN.