| Popis: |
Reactively sputtered TaSixNy films have been investigated as gate electrodes for dual gate Si-complementary metal-oxide-semiconductor devices. The as-deposited TaSixNy films were amorphous over a wide range of compositions. After annealing at 1000 °C, Ta30Si33N37 film became crystalline, however Ta26Si28N52 film remained amorphous. The x-ray photoelectron spectroscopy shows a significant increase of Si–N bonding in the TaSixNy films with increasing N content. The presence of Si–N bonds is attributed to cause the amorphous nature of the high N containing TaSixNy films. The work functions of TaSixNy films were extracted by capacitance–voltage analysis. The work function values for TaSixNy films with varying N contents range from 4.26 to 4.35 eV after forming gas annealing at 400 °C for 30 min, suggesting that TaSixNy films have work functions appropriate for n-type metal-oxide-semiconductor devices. However, it was observed, after 1000 °C anneals, that the work function of TaSixNy films increased to ∼4.8 eV... |
