Premium
Amorphous‐oxide TFT backplane for large‐sized AMOLED TVs
Author(s) -
Mo Yeon Gon,
Kim Minkyu,
Kang Chul Kyu,
Jeong Jong Han,
Park Yong Sung,
Choi Chaun Gi,
Kim Hye Dong,
Kim Sang Soo
Publication year - 2011
Publication title -
journal of the society for information display
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.578
H-Index - 52
eISSN - 1938-3657
pISSN - 1071-0922
DOI - 10.1889/jsid19.1.16
Subject(s) - amoled , thin film transistor , materials science , backplane , optoelectronics , oxide thin film transistor , active matrix , oled , threshold voltage , amorphous solid , transistor , electrical engineering , computer science , voltage , layer (electronics) , nanotechnology , computer hardware , chemistry , engineering , organic chemistry
— Amorphous‐oxide thin‐film‐transistor (TFT) arrays have been developed as TFT backplanes for large‐sized active‐matrix organic light‐emitting‐diode (AMOLED) displays. An amorphous‐IGZO (indium gallium zinc oxide) bottom‐gate TFT with an etch‐stop layer (ESL) delivered excel lent electrical performance with a field‐effect mobility of 21 cm 2 /V‐sec, an on/off ratio of >10 8 , and a subthreshold slope (SS) of 0.29 V/dec. Also, a new pixel circuit for AMOLED displays based on amorphous‐oxide semiconductor TFTs is proposed. The circuit consists of four switching TFTs and one driving TFT. The circuit simulation results showed that the new pixel circuit has better performance than conventional threshold‐voltage (V TH ) compensation pixel circuits, especially in the negative state. A full‐color 19‐in. AMOLED display with the new pixel circuit was fabricated, and the pixel circuit operation was verified in a 19‐in. AMOLED display. The AMOLED display with a‐IGZO TFT array is promising for large‐sized TV because a‐IGZO TFTs can provide a large‐sized backplane with excellent uniformity and device reliability.