Title :
Full-Swing a-IGZO Inverter With a Depletion Load Using Negative Bias Instability Under Light Illumination
Author :
Cho, In-Tak ; Lee, Ju-Wan ; Park, Jun-Mo ; Cheong, Woo-Seok ; Hwang, Chi-Sun ; Kwak, Joon-Seop ; Cho, Il-Hwan ; Kwon, Hyuck-In ; Shin, Hyungcheol ; Park, Byung-Gook ; Lee, Jong-Ho
Author_Institution :
Sch. of EECS, Seoul Nat. Univ., Seoul, South Korea
Abstract :
A high-performance amorphous indium-gallium-zinc-oxide thin-film transistor (TFT) inverter, which is composed of an enhancement mode driver and a depletion mode load, is implemented by selectively inducing the negative bias illumination temperature stress (NBITS) to the load TFT. Under NBITS, the transfer curve of the load TFT shows a parallel shift into the negative bias direction without a significant change in the subthreshold slope and recovers very slowly after terminating the NBITS even under harsh bias and temperature stress conditions. The proposed inverter shows much improved switching characteristics including higher voltage gain, wider swing range, and higher noise margins compared to the conventional inverter with an enhancement load.
Keywords :
II-VI semiconductors; amorphous semiconductors; gallium compounds; indium compounds; invertors; lighting; stability; thin film transistors; wide band gap semiconductors; zinc compounds; InGaZnO; NBITS; depletion load; depletion mode load; enhancement mode driver; full-swing inverter; high-performance amorphous indium-gallium-zinc-oxide thin-film transistor inverter; light illumination; load TFT; negative bias direction; negative bias illumination temperature stress; negative bias instability; parallel shift; subthreshold slope; Indium gallium zinc oxide; Inverters; Lighting; Logic circuits; Stress; Thin film transistors; Amorphous indium–gallium–zinc–oxide (IGZO); depletion mode; inverter; negative bias illumination temperature stress (NBITS); thin-film transistor (TFT);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2012.2221454
