Highly reliable radical SiO₂ films on atomically flat silicon surface formed by low temperature pure ar annealing

The gate oxide films are formed by the microwave exited high density plasma on Si(100) surfaces of various flatness to discuss the reliabilities. By annealing in ultra pure Ar ambient below 900 °C at atmosphere pressure, the whole surface of 200-mm-diameter (100) orientation silicon wafers can be atomically flattened without slip-line defects generation. For the capacitors, the intrinsic life time in charge-to-breakdown (Qbd) characteristics and the breakdown field (E_bd) of radical oxide films are much larger than those of thermal oxide films, and the extrinsic Qbd of radical oxide film is drastically improved by forming on atomically flat silicon surface composed with that on conventional Czochralski (Cz)-wafer surface. Moreover, fabricating radical oxide films on the atomically flat wafers, flattened at 800 or 1100 °C in Ar ambient, the equivalent gate oxide breakdown characteristics are obtained.