Program

O.4 -- Oral, IWTCP-3

Date: Monday, 27 July 2015

Time: 17h15 - 17h35

Theoretical evaluation of maximum electric field approximation of direct band-to-band tunneling Kane model for low bandgap semiconductors

Nguyen Dang Chien (1), Chun-Hsing Shih (2), Phu Chi Hoa (3), Nguyen Hong Minh (1), Duong Thi Thanh Hien (1) and Le Hong Nhung (3)

(1) Faculty of Physics, University of Da Lat, Lam Dong 671463, Vietnam (2) Department of Electrical Engineering, National Chi Nan University, Nantou 54561, Taiwan (3) Faculty of Postgraduate Studies, University of Da Lat, Lam Dong 671463, Vietnam

The two-band Kane model has been popularly used to calculate the band-to-band tunneling (BTBT) current in tunnel field-effect transistor (TFET) which is currently considered as a promising candidate for low power applications. This study theoretically clarifies the maximum electric field approximation (MEFA) of direct BTBT Kane model and evaluates its appropriateness for low bandgap semiconductors. By analysing the physical origin of each electric field term in the Kane model, it has been elucidated in the MEFA that the local electric field term must be remained while the nonlocal electric field terms are assigned by maximum value of electric field at the tunnel junction. Mathematical investigations have showed that the MEFA is more appropriate for low bandgap semiconductors compared to high bandgap materials because of enhanced tunneling probability in low field regions. The appropriateness of the MEFA is very useful for practical uses in quickly estimating the direct BTBT current in low bandgap TFET devices.

Presenter: Nguyen Dang Chien