Characteristics of low-energy nitrogen ion-implanted oxide and NO-annealed gate dielectrics

Observations of Lattice Distortions near Silicon Surfaces Implanted with Low-Energy Nitrogen Ions by Reflection X-ray Topography

“…Nitrogen implantation into silicon crystals is a particularly useful technique that makes possible the control of growth of thinner gate oxide layers (2 -3 nm), the formation of oxides of different thicknesses in metal-oxide-semiconductors (MOS) on a substrate, and it also forms a barrier to boron penetration at the Si/SiO 2 interface. Recently, several reports on nitrogen-implanted silicon crystals have been published to clarify several topics: the behavior of nitrogen diffusion in silicon, 11) the mechanism that reduces the SiO 2 thickness of implanted wafers, 12) the effects of nitrogen ion implantation and thermal oxidation on MOS characteristics, 13,14) and the implanted nitrogen distribution and electrical properties of oxides formed by very low energy implantation. 15) While the behavior of nitrogen diffusion in silicon, the effects of implantation on reducting in oxide thickness, lattice damage including amorphization, and the electrical properties connected with implantation have been studied in detail, the recovery by annealing of crystallinity in damaged layers of silicon substrates induced by nitrogen implantation and local distortions at the boundary of implanted regions growing with increasing time are not well observed because of the short-range strain field near the surface.…”