San Francisco, California–Toshiba Corp. has developed a new gate oxide fabrication process, which the company reports offers faster processing, reduced power consumption, and much greater reliability than current methods.

Toshiba’s fabrication process uses deuterium in its gaseous state. While previous research had confirmed the effectiveness of deuterium annealing in reducing interface-defect generation at the gate oxide-silicon substrate interface, Toshiba has advanced the process to the level of suppressing stress-induced leakage current (SILC) and cut it by 30%.

The new process burns deuterium in ambient oxygen during the gate oxidation process, introducing deuterium atoms into the gate oxide as growing SiO2 film. Tests confirm that the process achieves more stable chemical bonding of deuterium atoms than the annealing process, according to Toshiba. SILC suppression was made even more effective, reports the company, by replacing SiH4 gas with SiD4 gas during polycrystalline silicon deposition of the gate electrode. The number of deuterium atoms in the SiO2 film after polycrystalline silicon deposition by SiD4 gas was 10 times larger than achieved with deuterium oxidation alone.

Toshiba believes that the primary value of its new oxidation process is its strong potential as a real-world solution compatible with the conventional oxidation process. Suppression of SILC can be achieved simply by changing from hydrogen gas, widely used for the gate oxidation process, to deuterium gas.