In-line control of nitrogen implanted silicon for advanced multi-gate oxide application

As semiconductor scaling downward, the multiple gate oxide in one chip offered more flexible design and wide application. Nitrogen-implanted-silicon (N-I-S) which is lower cost and higher reliability than traditional etch-and-grow method (Xu et al. (2004), In-Ho Nam et al. (2001), Bark (1998)). Nitrogen in silicon can retard the growth rate of oxide, and nitrogen in oxide can retard the penetration of boron into gate oxide to degrade the device. A new in-line monitoring scheme different to conventional GOX measurement have been proposed in this paper to characterize the N-I-S by using the spectroscopic ellipsometer and non-contact -V metrology. By these new methods, the oxide growth parameters and oxide interface and bulk properties can be easily controlled.