Radiation Damage in MOS Devices Underlying an Electron Beam Annealed SOI Structure

Radiation damage due to electron beam annealing has been investigated in MOS devices underlying an electron beam annealed Silicon-on-Insulator structure. A high degree of residual damage (surface state and positive charge) is found to exist in MOS devices. The damage can be easily annealed out by low temperature (500–550°C) furnace annealing, when underlying MOS devices exist outside the electron beam range. However, high temperature furnace annealing at about 1000°C is necessary to eliminate the damage, when the electron beam penetrate through the gate oxides in MOS devices. Use of a low energy electron beam is recommended, based on these results, for the Silicon-on-Insulator formation for three-dimensional ICs.