Low-temperature furnace-grown reoxidized nitrided oxide gate dielectrics as a barrier to boron penetration

摘要

Reoxidized nitrided oxide (ROXNOX) gate dielectrics can be used to block the diffusion of boron into the MOS channel region. However, fixed oxide charge annealing can mask the effects of boron in the channel, a particularly important consideration for low-temperature gate oxides. The authors separate the effect of fixed charge annealing from the effect of boron diffusion and demonstrate that a low-temperature furnace-grown reoxidized nitrided oxide has a substantial advantage over conventional gate oxides in protecting the channel from boron over a wide range of annealing times and temperatures. They also address the issue of fixed charge annealing in low-temperature reoxidized nitrided oxides and present an approach to maintain acceptable gate dielectric quality while preserving a low D-t product for integration into a scaled dual-gate CMOS process.