Study on adhesion properties of low dielectric constant films by stud pull test and modified edge lift-off test

Adhesion of low-k films to hardmask or underlayer were studied using stud pull test and modified edge lift off test (m-ELT). The adhesion of SiLK to hardmask was enhanced by depositing thin silicon rich oxide layer under conventional PECVD oxide hard mask. The enhancement of adhesion by the Si-rich oxide layer could be attributed to the increase of dangling bonds on the hardmask surface. Adhesion of SiLK to oxide underlayer was degraded by post-anneal at 430/spl deg/C and the above and 5-cycle annealing at 400/spl deg/C. The good correlation between stud pull test and m-ELT was shown in both SiLK and low-k CVD films.