1,721,002 research outputs found
Recordings of brain activity using Embedded, Inkjet-Printed Voltage Amplifiers based on Organic Electrochemical Transistor
No full text2
Inkjet printed low noise voltage amplifier based on organic electrochemical transistors for in vivo recordings of brain activity
No full text2
Transepithelial/transendothelial electrical resistance Measurement by Organic electrochemical transistor
No full textElectrical impedance sensing of biological systems, especially cultured epithelial cell layers, is now a common technique to monitor cell morphology, and cell layer/tissue integrity. Existing methods to measure electrical impdedance most often rely on a two electrode configuration, where low frequency signals are challenging to obtain for small devices and for tissues with high resistance, due to low current. Organic electrochemical transistors(OECTs) have been shown to efficiently transduce and amplify low-level ionic fluxes in biological systems into electronic output signals. Here we present the how to measure the transepithelial/transendothelial electrical resistance(TEER) by OECT. In this work, we apply from standard electrochemical impedance spectroscopy(EIS) analysis to OECT-based drain current measurement. The biotic/abiotic ensemble is modeled with a simple equivalent circuit and an analytical expression of the total impedance as a function of frequency is extracted. Our result provide improved impedance and oect based TEER measurment with optimized sensitivity.1
Fabrication of Inkjet-Printed Organic Electrochemcial Transistor
No full textOrganic electrochemical transistors (OECTs) have been a great potential for recording electrophysiology signal. The coupling between ionic and electronic charge within conductive polymer enables the formation of volumetric capacitance that makes OECTs with high signal amplification characteristic. Nevertheless, a conventional fabrication method of OECTs, a spin coating, have key limitations that have constrain of pattern design and many process steps, causing it difficult to control the channel thickness and reducing application opportunities. Here we present the development of inkjet-printed OECTs to leverage drop-on-demand printing technology for facile design and simple fabrication. We first optimize the rheology of conductive polymer ink and inkjet waveform for stable jetting condition, then examined the line formation by varying drop spacings. Using these optimal conditions, we investigated the electrical characteristics of inkjet-printed OECTs through tuning the thickness of channel. Our results can pave the way for the use of inkjet-printed OECTs in the high quality recordings of biological applications.1
높은 수율, 균일성을 갖는 잉크젯 인쇄 기반 능동형 트랜지스터 어레이
No full textSensor arrays based on thin film transistors (TFTs) have potential for various 2D sensing applications such as electronic skins and image sensors. Achieving high yield and uniformity of TFT array is therefore essential for high performance sensor arrays. In this work, we demonstrate inkjet-printed 10 × 10 active matrix TFT array with high yield and uniformity. We fabricate high performance 5-V operating staggered TFT by inkjet-printing process and extend it to active matrix array. Accordingly, we introduce design rules and optimization process of fabricating inkjet-printed TFT array with high yield. Uniformity of the array are enhanced through channel gap optimization and utilization of hydrophobic bank for uniform channel length and width, respectively. The fabricated array exhibited high yield of 98 % and high uniformity of variation on drain current less than 10 %. Finally, we demonstrate proof-of-concept pressure sensor array on biocompatible Parylene substrate for electronic skin application.2
A method to form anodic aluminum oxide dielectrics on separate gate patterns for the fabrication of ultra-flexible, low-voltage organic circuits
No full textAnodization of gate metals isan effective way to grow thin and robust metal oxide dielectrics to realizelow-voltage
organic field-effect transistors (FETs). However, this technique hasbeen rarely applied to organic circuits because it
is difficult to anodize anumber of isolated gate islands. In this study, we propose a method to form anodicaluminum
oxide (AAO) dielectric on gate pattern islands in a single step forthe fabrication of ultra-flexible, low-voltage organic
circuits. For this, a 2μm-thick Parylene substrate was formed on an aluminum (Al)-coated glasscarrier, and Al gate
patterns were thermally deposited.Then, the gate islands were connected to a bottom Allayer through via-holes.
After the anodizing process of the interconnected islands,the Parylene film was stripped from the Al-coated glass
carrier for the electricalisolation of the gates. Likewise, the AAO dielectrics formed on the gate patternislands
exhibited good electrical insulating properties and high capacitance values (190 nF·cm-2) with gooduniformity. By
using the proposed AAO-on-island process, we successfully fabricated-3 V-operating p-type organic polymer FETs
which have carrier mobilities of 0.2 cm2·V-1·s-1 and threshold voltages of -0.15 V.1
- …
