Characteristics of silicon oxide gate MOS capacitors formed by rapid thermal oxidation and annealing

Ultra-thin silicon oxide (SiO2) insulating films have been obtained. by rapid thermal oxidation (RTO) and annealing (RTA), using different temperatures of 600, 700, 800 and 960 degrees C for 40s, in oxygen and nitrogen, respectively. Characterization by Ellipsometry ( for fixed refractive index of 1.46), transmission electron microscopy (TEM), Fourier transform. infrared (FTIR) analyses reveals oxide thickness values between 2 and 10 nm, and the presence of Si-O bonds, confirming the ultra-thin silicon oxide film formation, respectively. Theses films have been used as gate insulators in MOS capacitors. These devices, with different Al, Al/Ti, N+ Poly-Si gate electrodes and sintering at 450 degrees C in forming gas, were fabricated. MOS capacitors were used to obtain capacitance-voltage (C-V) and current-voltage (I-V) measurements. A, relative dielectric constant of 3.9 was adopted to extract the Equivalent Oxide Thickness (EOT) of films from C-V curves under strong accumulation condition, resulting in values between 2 nm and 10 nm. Leakage gate current densities between 10 mA/Cm-2 and 2 A/cm(2) were obtained by I-V measurements for gate voltage of -1 V. These results indicate that the obtained dielectric gates can be used for MOS technologies with dimensions higher than 130 nm.