Title :
Significant Reduction of Dynamic Negative Bias Stress-Induced Degradation in Bridged-Grain Poly-Si TFTs
Author :
Meng Zhang ; Zhihe Xia ; Wei Zhou ; Rongsheng Chen ; Man Wong
Author_Institution :
State Key Lab. on Adv. Displays & Optoelectron. Technol., Hong Kong Univ. of Sci. & Technol., Hong Kong, China
Abstract :
The device degradation of bridged-grain (BG) polycrystalline silicon thin-film transistors under dynamic negative bias stress (NBS) is investigated for the first time. By employing a BG structure in the active channel, dynamic NBS-induced hot carrier degradation could be significantly reduced from -99.9% to -2.4% (104 s dynamic NBS), which is attributed to a sharing of the lateral electric field across the multiple p-n junctions inherent in the structure. The nonequilibrium junction degradation model is employed and developed, incorporated with TCAD simulations.
Keywords :
elemental semiconductors; hot carriers; semiconductor device models; semiconductor device reliability; silicon; thin film transistors; BG polycrystalline silicon thin-film transistors; Si; TCAD simulations; active channel; bridged-grain polysilicon TFT; device degradation reduction; dynamic NBS-induced hot carrier degradation; dynamic negative bias stress-induced degradation; lateral electric field; nonequilibrium junction degradation model; p-n junctions; Degradation; Junctions; NIST; Silicon; Stress; Thin film transistors; Bridged-grain; dynamic negative bias stress; hot carrier; polycrystalline silicon; thin film transistor;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2014.2377040