A Study of Electrical Characteristics Improvements in Sub-0.1 µm Gate Length MOSFETs by Low Temperature Operation

Morikazu TSUNO, Shin YOKOYAMA, Kentaro SHIBAHARA

Summary :

MOSFETs with sub-0.1 µm gate length were fabricated, and their low temperature operation was investigated. The drain current for drain voltage of 2 V increased monotonously as temperature was lowered to 15 K without an influence of the freeze-out effect. Moreover, the increase in the drain current was enhanced by the gate length reduction. The hot-carrier effect at low temperature was also investigated. Impact-ionization decreased as temperature was lowered under the condition of drain voltage 2 V. The decreasing ratio was enhanced as gate length became shorter. We consider this phenomenon is attributed to the non-steady-stationary effect. As a result, device degradation by DC stressing was reduced at 77 K in comparison with room temperature. In the case of 0.1 µm MOSFET, drain current was not degraded in condition of DC stress with gate- and drain-voltage was 1.5 V.

• Publication: IEICE TRANSACTIONS on Electronics Vol.E81-C No.12 pp.1913-1917
• Publication Date: 1998/12/25
• Category: Semiconductor Materials and Devices

Authors

Morikazu TSUNO
Shin YOKOYAMA
Kentaro SHIBAHARA

Keyword

MOSFET,  low temperature,  velocity overshoot,  Sb,  nonsteady-stationary effect,  impact ionization,  hot-carrier