Title :
A novel ultrathin elevated channel low-temperature poly-Si TFT
Author :
Zhang, Shengdong ; Zhu, Chunxiang ; Sin, Johnny K O ; Mok, Philip K T
Author_Institution :
Dept. of Electr. & Electron. Eng., Hong Kong Univ. of Sci. & Technol., Kowloon, Hong Kong
Abstract :
A novel ultrathin elevated channel thin-film transistor (UT-ECTFT) made using low-temperature poly-Si is proposed. The structure has an ultrathin channel region (300 /spl Aring/) and a thick drain/source region. The thin channel is connected to the heavily doped drain/source through a lightly doped overlapped region. The lightly doped overlapped region provides an effective way to spread out the electric field at the drain, thereby reducing significantly the lateral electric field there at high drain bias. Thus, the UT-ECTFT exhibits excellent current saturation characteristics even at high bias (V/sub ds/=30 V, V/sub gs/=20 V). Moreover, the UT-ECTFT has more than two times increase in on-state current and 3.5 times reduction in off-state current compared to conventional thick channel TFT´s.
Keywords :
doping profiles; elemental semiconductors; liquid crystal displays; semiconductor device breakdown; semiconductor device measurement; silicon; thin film transistors; 20 V; 30 V; 300 angstrom; 600 C; Si-SiO/sub 2/; breakdown characteristics; current saturation characteristics; electric field distribution; fully integrated AM-LCD system; heavily doped drain/source; high drain bias; lateral electric field; lightly doped overlapped region; off-state current; on-state current; polysilicon ultrathin elevated channel low-temperature TFT; thick drain/source region; ultrathin channel region; Active matrix liquid crystal displays; Contact resistance; Digital circuits; Electric breakdown; Fabrication; Glass; Insulation; Operational amplifiers; Silicon compounds; Thin film transistors;
Journal_Title :
Electron Device Letters, IEEE
