Analysis of low frequency noise characteristics in p-type polycrystalline silicon thin film transistors

作者：Liu Yuan; En Yun Fei; Fang Wen Xiao

来源：Modern Physics Letters B, 2017, 31(19-21): 1740020.

DOI：10.1142/S0217984917400206

• Polycrystalline silicon
• thin film transistor
• low frequency noise
• distribution of states

Low frequency noises in the p-type polycrystalline silicon thin film transistors are invest igated. It shows a pure 1/f(gamma) (with gamma near one) noise behavior which can be explained by emission and trapping processes of carriers between trapping states. Subsequently, the gate voltage-dependent drain current noise power spectral densities closely follow the mobility fluctuation model, and the average Hooge's parameter is then extracted. By considering traditional tunneling processes, the flat-band voltage spectral density is extracted and the concentration of traps in the grain boundary is calculated to be 7.17 x 10(20) cm(-3) eV(-1). By converting the frequency to tunneling depth of carriers in the gate oxide, the spatial distribution of gate oxide trapped charges are obtained. Finally, the distribution of localized states in the energy band is extracted. The experimental results show an exponential deep states and tail states distribution in the band gap while N-DD is about 1.5 x 10(20) cm(-3) eV(-1), T-DD is similar to 617K, N-TD is similar to 3.6 x 10(21) cm(-3) eV(-1) and T-TD is similar to 265K.

• 出版日期2017-7-30