A Strategy Of Eliminating Salicide Block Film Bubbles

Fluorine (F) is a co-implant species, which have numbers of beneficial effects to the semiconductor device. F co-implant has been shown to reduce boron (B) transient enhanced diffusion and deactivation when coupled with conventional spike rapid thermal anneals (RTA). However, salicide block (SAB) film easily suffers bubble defects due to the implant of F. In this paper, SAB bubbles have been observed clearly when the doses of BF2 exceed $3.0\times 10^{15}\ \text{cm}^{-2}$ after RTA. Moreover, a defect-free SAB layer has been obtained by adjusting the implant conditions.