1/f γ noise in polycrystalline silicon thin-film transistors

Abstract

Polycrystalline silicon thin-film transistors show a 1/fγ (with γ<1) low frequency noise behavior. The 1/fγ noise is explained by emission and trapping processes of carriers between trapping states located within an energy range of kT around the Fermi level and the exponential tail states. We have derived a simple relationship between the frequency index γ of the noise spectrum and the energy distribution parameter of the tail states. From the experimental noise data, the theoretical model allows us to determine the tail states energy distribution and the grain boundary trap density.

Flat panel imagers with pixel level amplifiers based on polycrystalline silicon thin-film transistor technology

“…First, although 1/f noise has been observed as the dominant noise for poly-Si TFTs, 8 it is not obvious to expect a 1/f noise spectrum in the measurement described above, since our conditions differ substantially from the usual ones. For our system, the TFT responsible for generating noise, T F , is switched on and off between each data point.…”

“…Second, the noise spectrum measured here is a direct measurement of V T fluctuation of TFT T F instead of drain current fluctuation. 8 Since the pixel level source follower amplifier is configured as a charge amplifier, the drain current drops to zero at the end of each charging cycle of C data and can contribute little to the charge fluctuation in C data . According to Eq.…”

Instability of Indium Zinc Oxide Thin-Film Transistors Under Transmission Line Pulsed Stress

“…The normalized current spectral density (S ID /I 2 D ) increases after TLP stress. The devices show a 1/f γ low frequency noise behavior which can be explained by emission and trapping processes of carriers between localized states [11]. According to the carrier number fluctuation model, S ID /I 2 D can be expressed by [3], [11], [12]:…”

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

“…8 In the n-channel poly-Si TFTs, noise usually shows a 1/f γ law with doped or undoped active layer. 3,9 However, the dominant mechanism of noise in the p-type poly-Si TFTs is still less reported. 4 The investigation of low frequency noise in the p-type poly-Si TFT may help to understand the origin and physical mechanism of noise.…”

“…1,2 The noise properties of poly-Si TFTs are of major importance in circuit design and reliability evaluation, 3,4 These low frequency noises may be converted to high frequencies which is a dominant contributor to phase noise, thus adversely affecting the operation of devices in analog applications. 5 Therefore, it is necessary to examine and minimize the low frequency noise in the poly-Si TFTs.…”