Comparison of the degradation characteristics of AlON/InGaAs and Al₂O₃/InGaAs stacks

TY - JOUR

T1 - Comparison of the degradation characteristics of AlON/InGaAs and Al2O3/InGaAs stacks

AU - Palumbo, F.

AU - Krylov, I.

AU - Eizenberg, M.

N1 - Publisher Copyright: © 2015 AIP Publishing LLC.

PY - 2015/3/14

Y1 - 2015/3/14

N2 - In this paper, the degradation characteristics of MOS (Metal-Oxide-Semiconductor) stacks with Al2O3/AlON or Al2O3 only as dielectric layers on InGaAs were studied. The dielectric nitrides are proposed as possible passivation layers to prevent InGaAs oxidation. At negative bias, it has been found out that the main contribution to the overall degradation of the gate oxide is dominated by the generation of positive charge in the gate oxide. This effect is pronounced in MOS stacks with Al2O3/AlON as dielectric, where we think the positive charge is mainly generated in the AlON interlayer. At positive bias, the degradation is dominated by buildup of negative charge due to electron trapping in pre-existing or stress-induced traps. For stress biases where the leakage currents are low, the changes in the electrical characteristics are dominated by electron-trapping into traps located in energy levels in the upper part of the semiconductor gap. For stress biases with higher leakage current levels, the electron trapping occurs in stress-induced traps increasing the shift of VFB towards positive bias. The overall results clearly show that the improvement of the high-k dielectric/InGaAs interface by introducing N into the Al-oxide does not necessarily mean an increase in the reliability of the MOS stack.

AB - In this paper, the degradation characteristics of MOS (Metal-Oxide-Semiconductor) stacks with Al2O3/AlON or Al2O3 only as dielectric layers on InGaAs were studied. The dielectric nitrides are proposed as possible passivation layers to prevent InGaAs oxidation. At negative bias, it has been found out that the main contribution to the overall degradation of the gate oxide is dominated by the generation of positive charge in the gate oxide. This effect is pronounced in MOS stacks with Al2O3/AlON as dielectric, where we think the positive charge is mainly generated in the AlON interlayer. At positive bias, the degradation is dominated by buildup of negative charge due to electron trapping in pre-existing or stress-induced traps. For stress biases where the leakage currents are low, the changes in the electrical characteristics are dominated by electron-trapping into traps located in energy levels in the upper part of the semiconductor gap. For stress biases with higher leakage current levels, the electron trapping occurs in stress-induced traps increasing the shift of VFB towards positive bias. The overall results clearly show that the improvement of the high-k dielectric/InGaAs interface by introducing N into the Al-oxide does not necessarily mean an increase in the reliability of the MOS stack.

UR - http://www.scopus.com/inward/record.url?scp=84924870524&partnerID=8YFLogxK

U2 - 10.1063/1.4914492

DO - 10.1063/1.4914492

M3 - 文章

AN - SCOPUS:84924870524

SN - 0021-8979

VL - 117

JO - Journal of Applied Physics

JF - Journal of Applied Physics

IS - 10

M1 - 104103

ER -