论文信息 - Interface trap induced thermionic and field emission current in off-state MOSFET's

Interface trap induced thermionic and field emission current in off-state MOSFET's

An interface trap-assisted tunneling and thermionic emission model has been developed to study an increased drain leakage current in off-state MOSFET's after hot carrier stress. In the model, a complete band-trap-band leakage path is formed at the Si-SiO/sub 2/ interface by hole emission from interface traps to the valence band and electron emission from interface traps to the conduction band. Both hole and electron emissions are carried out via quantum tunneling or thermal excitation. In experiment, a 0.5 /spl mu/m n-MOSFET was subject to hot carrier stress to generate interface traps. The drain leakage current was characterized to compare with the model. Our study reveals that the interface trap-assisted two-step tunneling, hole tunneling followed by electron tunneling, is responsible for the leakage current at a large drain-to-gate bias (V/sub dg/) The lateral field plays a dominant role in the two-step tunneling process. As V/sub dg/ decreases, a thermionic-field emission mechanism, hole thermionic emission and electron tunneling, becomes a primary leakage path. At a sufficiently low V/sub dg/, our model reduces to the Shockley-Read-Hall theory and thermal generation of electron hole pairs through traps is dominant.<<ETX>>

[1] Steve S. Chung,et al. Effects of hot carrier induced interface state generation in submicron LDD MOSFET's , 1994 .

[2] D. Wen,et al. Tunneling leakage in Ge preamorphized shallow junctions , 1988 .

[3] C.W. Teng,et al. Interface trap-enhanced gate-induced leakage current in MOSFET , 1989, IEEE Electron Device Letters.

[4] A.B. Joshi,et al. Hot-carrier-stress effects on gate-induced drain leakage current in n-channel MOSFETs , 1991, IEEE Electron Device Letters.

[5] T. Hori,et al. Drain-structure design for reduced band-to-band and band-to-defect tunneling leakage , 1990, Digest of Technical Papers.1990 Symposium on VLSI Technology.

[6] T.Y. Chan,et al. The impact of gate-induced drain leakage current on MOSFET scaling , 1987, 1987 International Electron Devices Meeting.

[7] K. Hashimoto,et al. Hot-carrier induced drain leakage current in n-channel MOSFET , 1987, 1987 International Electron Devices Meeting.

[8] C. Hu,et al. Design for suppression of gate-induced drain leakage in LDD MOSFETs using a quasi-two-dimensional analytical model , 1992 .

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

[10] C. Y. Chang,et al. Interface trap effect on gate induced drain leakage current in submicron N-MOSFET's , 1994 .