Dry oxidation and wet oxidation processes of silicon have been examined experimentally. The oxidation temperatures were 1.10$0^{circ}C$, 1.15$0^{circ}C$, and 1.200 $^{circ}C$, and oxygen flow rate was changed from 0.2 liter/min to 2.8 liter/min. From the experimental measurements, oxidation temperaturel time and oxygen flow rate have been tabutated for oxide layers 0.1$mu$ - 1.0$mu$ in thickness. The quality of the grown oxide layer has been investigated In terms of the dielectric constant, breakdown voltage, fixed surface charge densify (Qss/q) and mobile charge density (Q /q). From these measurements, it is concluded that the quality of the oxide layer is sufficient to expect the normal operation of MOS transistors.