Frequency-dependent capacitance reduction in high-k AlTiOx and Al2O3 gate dielectrics from IF to RF frequency range

We have characterized the capacitance and loss tangent for high-k Al/sub 2/O/sub 3/ and AlTiO/sub x/ gate dielectrics from IF (100 KHz) to RF (20 GHz) frequency range. Nearly the same rate of capacitance reduction as SiO/sub 2/ was demonstrated individually by the proposed Al/sub 2/O/sub 3/ and AlTiO/sub x/ gate dielectrics as frequency was increased. Moreover, both dielectrics preserve the higher k better than SiO/sub 2/ from 100 KHz to 20 GHz. These results suggest that both Al/sub 2/O/sub 3/ and AlTiO/sub x/ are suitable for next generation MOSFET application into RF frequency regime.