Defects in solid phase and laser crystallised polysilicon thin film transistors

Growth kinetics and crystallographic properties of polysilicon thin films formed by aluminium-induced crystallization

“…This means that twinning does not seem to explain the branching form of the crystalline Si. This is in contrast to the observations after solid-phase crystallization of a-Si where the grain shape is irregular as well with twins extending along the main axis of the grain arms [37]. A 1200 Â 900 mm 2 map was also performed on the sample annealed at 450 1C and very comparable results to the small area one were obtained in terms of grain size, boundary types and orientation.…”

Stability improvement of deuterated amorphous silicon thin-film transistors characterized by modified Schottky-contact gated-four-probe method

“…Charge density trapping in the a-SiN X :H layer at or near the a-Si:H/a-SiN X :H interface (n t ) could be calculated through n t ϭC i (⌬V TE ϩ⌬V TH )/2q, 16 with C i presenting the insulator capacitance per unit area, in our case, it is 2.2 ϫ10 Ϫ8 F/cm 2 . Average n t of 6.1ϫ10 10 /cm 2 are trapped in the insulator after 10 000 s bias at 10 V. By using S ϭkT ln 10/q(1ϩq 2 N SS /C i ϩͱq 2 ⑀ Si N ds /C i ), [17][18][19] where C i , ⑀ Si , and q represent the insulator capacitance per unit area, the silicon dielectric constant, and absolute value of the electron charge, one gets the defect density in the conducting channel of an a-Si TFT, n ds ϭN ds ϫE G , through subthreshold ͑S͒, interface trapped defect density, n t ϭN SS ϫE G , and optical gap of a-Si:H͑D) E G , 1.7 eV. Since S E and S H change from 1.3 to 1.4 V/dec and 4.7 to 5.2 V/dec, respectively, after a 10 000 s bias stress at 10 V, the DOS increases from 3.31ϫ10 18 to 3.87ϫ10 18 /cm 3 and 4.72ϫ10 19 to 5.79 ϫ10 19 /cm 3 near the conduction and valence band mobility edge, respectively.…”

New Crystallization Method of Amorphous Silicon by Selective Area Heating for Stamp Process

“…We confirmed the structure of SAH poly-Si to be similar to the conventional SPC of a-Si. The grain structure was a dendritic structure with twins extending along the principal axis of the grains [14,15]. The grain sizes were smaller than 100 nm.…”