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Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection
Published on: February 1, 2022
Ambipolar to unipolar conversion in graphene field-effect transistors
Hong Li1, Qing Zhang, Chao Liu
1Microelectronics Centre, School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798.
ACS Nano
|March 19, 2011
Summary
Researchers developed unipolar graphene field-effect transistors (GFETs) by using titanium oxide for tunable doping. This breakthrough enables air-stable complementary circuits compatible with CMOS technology.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Graphene field-effect transistors (GFETs) typically exhibit ambipolar conduction, limiting their use in certain electronic applications.
- Unipolar operation is desirable for specific semiconductor device functionalities.
Purpose of the Study:
- To develop unipolar GFETs with tunable characteristics.
- To demonstrate the fabrication of complementary circuits using unipolar GFETs.
Main Methods:
- Utilizing titanium oxide on graphene to induce hole doping.
- Tuning the threshold voltage of p-type GFETs via etching to control titanium oxide density.
- Converting p-type GFETs to n-type GFETs through annealing and silicon nitride passivation.
- Integrating p- and n-type GFETs into a complementary inverter.
Main Results:
- Achieved unipolar p-type GFETs with tunable threshold voltages.
- Successfully converted p-type GFETs to unipolar n-type GFETs.
- Demonstrated an air-stable complementary inverter using the developed unipolar GFETs.
- Confirmed compatibility of fabrication processes with conventional CMOS technology.
Conclusions:
- Titanium oxide is an effective material for inducing and tuning unipolar behavior in GFETs.
- The developed fabrication methods allow for the creation of both p-type and n-type unipolar GFETs.
- The successful demonstration of a complementary inverter highlights the potential of these unipolar GFETs for practical electronic applications.
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