Title :
IGZO TFT-Based All-Enhancement Operational Amplifier Bent to a Radius of 5 mm
Author :
Zysset, Christoph ; Munzenrieder, N. ; Petti, L. ; Buthe, L. ; Salvatore, G.A. ; Troster, G.
Author_Institution :
Inst. for Electron., Swiss Fed. Inst. of Technol. Zurich, Zürich, Switzerland
Abstract :
An all-enhancement operational amplifier operating at 5 V and comprising 16 n-type amorphous indium-gallium-zinc-oxide thin-film transistors (TFTs) is fabricated on a 50 μm thick flexible polyimide substrate. The operational amplifier has an open loop voltage gain of 18.7 dB and a unity-gain frequency of 472 kHz while the common-mode rejection ratio (CMMR) is larger than 40 dB. The mechanical flexibility of the amplifier is demonstrated by bending the circuit to a radius of 5 mm, which corresponds to a tensile strain of 0.5% parallel to the TFT channels. The bent amplifier shows the same output behavior as when flat. The power consumption of the operational amplifier is 900 μW, regardless whether the circuit is flat or bent.
Keywords :
amorphous semiconductors; gallium compounds; indium compounds; internal stresses; operational amplifiers; thin film transistors; zinc compounds; IGZO TFT-based all-enhancement operational amplifier; InGaZnO; amorphous indium-gallium- zinc-oxide thin-film transistors; common-mode rejection ratio; frequency 472 kHz; gain 18.7 dB; mechanical flexibility; open loop voltage gain; power 900 muW; power consumption; radius 5 mm; size 50 mum; tensile strain; thick flexible polyimide substrate; unity-gain frequency; voltage 5 V; Frequency measurement; Gain; Strain; Substrates; Thin film transistors; Voltage measurement; Analog circuits; indium–gallium-zinc–oxide (IGZO); operational amplifiers; thin-film circuits; thin-film transistors (TFTs);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2013.2280024
