Details

Autor(en) / Beteiligte

• Pandey, Utkarsh
• Pal, Nila
• Acharya, Vishwas
• Aich, Pijush Kanti
• Yadav, Akhilesh Kumar
• Pal, Bhola Nath

Titel

Dual gated Low Operating Voltage Metal Oxide Thin film transistor for highly sensitive and fast-response pressure sensing application

Ist Teil von

• IEEE sensors journal, 2023-06, Vol.23 (11), p.1-1

Ort / Verlag

IEEE

Erscheinungsjahr

2023

Quelle

IEEE Electronic Library Online

Beschreibungen/Notizen

• A solution-processed low operating voltage dual gated metal oxide thin film transistor (TFT) has been fabricated for pressure sensing applications. This device has been fabricated on a p-doped Si (p + -Si) using Li-Alumina (Li-Al 2 O 3 ) as a bottom gate dielectric and SnO 2 thin film as a semiconductor channel. Besides, piezoelectric poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) thin film has been utilized as the top gate and dielectric on which external pressure has been applied. During bottom gate biasing, this TFT shows an n-channel behavior within 2 V operating voltage. Under such operation, the obtained value of threshold voltage (V th ), carrier mobility (μ), and On/Off ratio of this device is 0.12 V, 2.60 cm 2 .V -1 .s -1 , and 1.21 × 10 4 , respectively. After applying pressure under accumulation mode operation, drain current (I D ) of the device reduces and the OFF current factor increases. Besides, the V th of the device shifts towards higher positive gate voltage when external pressure has varied from 0.8 mbar to 1.6 bar. The drain current reduction, enhancement of OFF current factor, and V th shifting during the application of pressure of 1.6 bar are 50, 300, and 2000% respectively w.r.t their normal operation. The variation of all these parameters has two distinct regions with good linearity, one is < 80 mbar and the other is > 80 mbar, which is due to the saturation of orientation of the electric dipole of PVDF-HFP under a certain pressure range (< 80 mbar). Moreover, device response and recovery time are 90 and 5 ms respectively, indicating its prompt response to external pressure.