Title :
Development of high-performance polycrystalline silicon thin-film transistors (TFTs) using defect control process technologies
Author :
Higashi, Seiichiro ; Abe, Daisuke ; Hiroshima, Yasushi ; Miyashita, Kazuyuki ; Kawamura, Takahiro ; Inoue, Satoshi ; Shimoda, Tatsuya
Author_Institution :
Technol. Platform Res. Center, Seiko Epson Corp., Nagano, Japan
fDate :
7/1/2002 12:00:00 AM
Abstract :
High-performance polycrystalline Si (poly-Si) thin-film transistors (TFTs) were successfully fabricated on a glass substrate below 425/spl deg/C by introducing defect control process technologies. The defects in the laser crystallized poly-Si films were terminated by an oxygen plasma treatment to the film and the defects at the SiO/sub 2//Si interface were controlled by a gate SiO/sub 2/ film formation using electron cyclotron resonance (ECR) plasma enhanced chemical vapor deposition (PECVD). As a result, high n-channel mobility of 309 cm/sup 2/V/sup -1/s/sup -1/, low threshold voltage of 1.12 V and low subthreshold swing of 250 mV/decade were obtained. In addition, it was demonstrated that the defect control process is quite effective to minimize the variation of TFT characteristics.
Keywords :
driver circuits; elemental semiconductors; interface states; laser beam annealing; plasma CVD; silicon; thin film transistors; ECR PECVD; SiO/sub 2/-Si; defect control process technologies; excimer laser annealing; fabrication process; gate film formation; glass substrate; high n-channel mobility; high-performance polysilicon TFT; interface defects; laser crystallized films; low subthreshold swing; low threshold voltage; oxygen plasma treatment; preferential orientation; trap states; Chemical lasers; Crystallization; Glass; Plasma chemistry; Process control; Semiconductor films; Semiconductor thin films; Silicon; Substrates; Thin film transistors;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2002.1015218
