Open AccessLow frequency noise in polysilicon thin film transistors: effect of the laser annealing of the active layer
Author(s) -
Pichon L.,
Boukhenoufa A.,
Cordier C.
Publication year - 2008
Publication title -
physica status solidi c
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 46
eISSN - 1610-1642
pISSN - 1862-6351
DOI - 10.1002/pssc.200779510
Subject(s) - materials science , active layer , optoelectronics , thin film transistor , transistor , infrasound , annealing (glass) , silicon , laser , polysilicon depletion effect , layer (electronics) , nanotechnology , electrical engineering , optics , voltage , gate oxide , composite material , physics , acoustics , engineering
Low‐frequency noise is studied in N‐channel polysilicon TFTs issued from two (low temperature ≤600 °C) technologies: furnace solid phase crystallized (FSPC) and laser solid phase crystallized (LSPC) TFTs. The distribution of the trap states (DOS) into the polysilicon bandgap determined for devices biased in the weak inversion is one decade lower for LSPC devices. The high range values (10 –4 ≤ α ≤ 1) of the measured macroscopic noise parameter, defined according to the Hooge empirical relationship, are explained by the drain current crowding due to structural defects within the active layer. The higher values of α for the LSPC TFTs are attributed to a better structural quality of the active layer. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)