Evaluation of buried oxide formation in low-dose SIMOX process

Formation of a buried oxide BOX.layer during high-temperature annealing in a separation by implanted oxygen SIMOX.process was evaluated by means of Fourier-transform infrared FTIR.absorption spectroscopy. The evaluation results suggested that the formation process could be controlled by changing the ramping rate and the oxygen concentration in the atmosphere during high-temperature annealing. This was confirmed through TEM observation after annealing under various conditions. Reduction of the Oq implantation dose was enabled by adopting a slow ramping rate for the annealing. Novel Si-on-insulator SOI.structures with a BOX layer at the damage-peak Dp.depth and a double BOX layer at both Dp and Rp projection range.depths were obtained, depending on the Oq implantation dose, by applying a combination of a slow ramping rate and a high oxygen concentration in the atmosphere. The atmospheric oxygen enhanced the growth of the oxide precipitate and smoothed the SiO2rSi interfaces of the SOI structures. q2000 Elsevier Science B.V. All rights reserved.