Title :
Radiation hardened micron and submicron MOSFETs containing fluorinated oxides
Author :
Nishioka, Yasushiro ; Ohyu, Kiyonori ; Ohji, Yuzuru ; Kato, Masataka ; Da Silva, Eronides F., Jr. ; Ma, T.P.
Author_Institution :
Hitachi Ltd., Tokyo, Japan
fDate :
12/1/1989 12:00:00 AM
Abstract :
The generation of interface traps and oxide trapped charge in fluorinated MOSFETs and MOS capacitors has been found to depend strongly on the amount of fluorine introduced. In this study, the fluorine is introduced by low-energy F implantation into the surface layer of the polycrystalline silicon gate electrode, followed by annealing at 950°C to diffuse F into the gate SiO2, toward the SiO2/Si interface The improved interface radiation hardness is attributed to the strain relaxation near the SiO2/Si interface due to fluorine incorporation. An optimum F implant dose has been found to exist for a given technology; in the present case the optimum dose appears to be 2×1015 cm-2. The results demonstrate the potential of the technique for producing radiation hard micron and submicron MOS devices
Keywords :
X-ray effects; annealing; elemental semiconductors; fluorine; insulated gate field effect transistors; ion implantation; metal-insulator-semiconductor devices; radiation hardening (electronics); semiconductor-insulator boundaries; silicon; silicon compounds; 950 C; F incorporation; MOS capacitors; Si-SiO2; Si:F-SiO2:F; X-ray irradiation; annealing; fluorinated MOSFET; interface radiation hardness; interface traps; low energy ion implantation; micron MOS device; oxide trapped charge; semiconductor; strain relaxation; submicron MOS devices; Annealing; Electrodes; Implants; MOS capacitors; MOS devices; MOSFETs; Oxidation; Radiation hardening; Silicon; Surface treatment;
Journal_Title :
Nuclear Science, IEEE Transactions on
