Title :
Flexible Three-Bit-Per-Cell Resistive Switching Memory Using a-IGZO TFTs
Author :
Shih-Chieh Wu ; Hsien-Tsung Feng ; Ming-Jiue Yu ; I-Ting Wang ; Tuo-Hung Hou
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
This letter proposes a novel high bit density nonvolatile memory using a logic compatible flexible amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistor (TFT) structure fabricated at low temperature. Before electrical forming, the a-IGZO TFT exhibits excellent transistor performance, including an ON/OFF current ratio of 8.8×106, a steep subthreshold slope of 0.14 V/decade, a threshold voltage of 0.55 V, and a maximum field-effect mobility of 2 cm2/Vs. After electrical forming, a three-bit-per-cell resistive switching memory is realized using localized multilevel resistance states at the drain and source bits. Combining dual functionalities to achieve low-cost integration and excellent device characteristics at bending states, the proposed device is promising for future system-on-plastic applications.
Keywords :
III-V semiconductors; amorphous semiconductors; bending; electric resistance; field effect memory circuits; flexible electronics; gallium compounds; indium compounds; semiconductor thin films; thin film transistors; zinc compounds; InGaZnO; a-IGZO TFT; drain bits; flexible three-bit-per-cell resistive switching memory; high bit density nonvolatile memory; logic compatible flexible amorphous thin-film transistor; maximum field-effect mobility; multilevel resistance states; on-off current ratio; source bits; system-on-plastic applications; threshold voltage; transistor performance; voltage 0.55 V; Logic gates; Nonvolatile memory; Resistance; Substrates; Switches; Thin film transistors; Amorphous indium–gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs); flexible electronics; random access memory (RRAM); resistive switching; three-bit-per-cell;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2013.2278098
