High-integrity, ultra-thin gate oxides for advanced ULSI

Uniformity control and high reliability of ultra-thin gate oxides are important issues for giga bit integration. We have quantitatively analyzed the measured tunneling current through 3.0-6.0 nm thick gate oxides and found excellent agreement between the measured and calculated current. The tunneling effective mass obtained as the only fitting parameter remains almost constant regardless of the oxide thickness. The charge to breakdown of the gate oxide is higher than 1.0 C/cm² and significantly increased to about 100 C/cm² for a 3.0 nm thick oxide. The tunneling current density distribution on the wafer is extremely homogeneous, indicating the excellent uniformity of oxides grown on the hydrogen-terminated, flat Si(100) wafers