Unification of three multiphonon trap-assisted tunneling mechanisms

There are three basic multiphonon trap-assisted tunneling (TAT) mechanisms in the gate leakage current of a metal-oxide-semiconductor (MOS) structure: the short-ranged trap potential, nonadiabatic interaction and electric field induced trap-band transitions. In this paper, a comparison of these three mechanisms is made for the first time in a single (Schenk’s model) MOS structure. A properly box-normalized electron wave function in the SiO2 conduction band in an electric field is used to calculate the field ionization rate of a deep neutral trap. It is found that capture and emission rates of a deep neutral trap are almost the same in the short-ranged trap potential and nonadiabatic interaction induced TAT processes, so the two mechanisms give a similar contribution to the total TAT current. The calculated TAT current and the average relaxation energy (∼1.5 eV) due to these two mechanisms are in good agreement with the experimental results. In contrast, capture and emission rates in Schenk’s model are sev...

[1]  C. Sah.  Electronic Processes and Excess Currents in Gold-Doped Narrow Silicon Junctions , 1961 .

[2]  Andrea L. Lacaita,et al.  Modeling of SILC based on electron and hole tunneling. I. Transient effects , 2000 .

[3]  J. Han,et al.  Phonon-coupled trap-assisted charge injection in metal-nitride-oxide-silicon/silicon-oxide-nitride-oxide-silicon structures , 2009 .

[4]  A. Gehring,et al.  Modeling of wearout, leakage, and breakdown of gate dielectrics [MOSFET] , 2004, Proceedings of the 11th International Symposium on the Physical and Failure Analysis of Integrated Circuits. IPFA 2004 (IEEE Cat. No.04TH8743).

[5]  M. Lannoo,et al.  Theoretical and experimental aspects of the thermal dependence of electron capture coefficients , 1990 .

[6]  S. Ganichev,et al.  Deep impurity-center ionization by far-infrared radiation , 1997 .

[7]  I. Lundström,et al.  Tunneling to traps in insulators , 1972 .

[8]  Andreas Schenk,et al.  Field and high‐temperature dependence of the long term charge loss in erasable programmable read only memories: Measurements and modeling , 1995 .

[9]  W. B. Knowlton,et al.  A Physical Model of the Temperature Dependence of the Current Through $\hbox{SiO}_{2}\hbox{/}\hbox{HfO}_{2}$ Stacks , 2011, IEEE Transactions on Electron Devices.

[10]  J. Bardeen.  Tunnelling from a Many-Particle Point of View , 1961 .

[11]  Jin Cai,et al.  Gate tunneling currents in ultrathin oxide metal–oxide–silicon transistors , 2001 .

[12]  G. Lucovsky.  On the photoionization of deep impurity centers in semiconductors , 1993 .

[13]  Shinichi Takagi,et al.  Experimental evidence of inelastic tunneling in stress-induced leakage current , 1999 .

[14]  Francisco Jimenez-Molinos,et al.  Physical model for trap-assisted inelastic tunneling in metal-oxide-semiconductor structures , 2001 .

[15]  J. A. López-Villanueva,et al.  Quantum two-dimensional calculation of time constants of random telegraph signals in metal-oxide-semiconductor structures , 1997 .

[16]  Elyse Rosenbaum,et al.  Mechanism of stress-induced leakage current in MOS capacitors , 1997 .

[17]  S. Makram-Ebeid,et al.  Quantum model for phonon-assisted tunnel ionization of deep levels in a semiconductor , 1982 .