In this paper, we reported the effective mobility and the interface-state density of La
2O
3 nMISFETs fabricated under different post deposition annealing (PDA) conditions; annealing temperature (300°C - 600°C) and ambient (N
2 or O
2). High effective mobility of 312cm
2/Vs and low interface-state density of 6 × 10
10cm
-2/eV were obtained from La
2O
3 nMISFET with equivalent oxide thickness (EOT) of 1.7nm after PDA at 300°C in N
2 ambient for 10 minutes. Gate leakage current density was 6.8 × 10
-6A/cm
2. We found that peak effective mobility decreased with increasing anneal temperature, regardless of annealing ambient. We also observed a monotonous relationship between effective mobility and interface-state density. This behavior suggests that lowering the interface-state density is essential to obtain high mobility in the high-
κ/Si structure.
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