Electrical Characteristics and Stability Improvement of Top-Gate In-Ga-Zn-O Thin-Film Transistors with Al2O3/TEOS Oxide Gate Dielectrics
| Autor: | Chun Hung Lai, Lee Yih-Shing, Tsung Eong Hsieh, Wang Yu-Hsin, Tsung Cheng Tien |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Gate dielectric Oxide electrical characteristics 02 engineering and technology Dielectric 01 natural sciences law.invention Stress (mechanics) chemistry.chemical_compound law 0103 physical sciences Materials Chemistry 010302 applied physics top-gate a-IGZO thin-film transistors business.industry gate dielectrics Transistor Surfaces and Interfaces stability 021001 nanoscience & nanotechnology Surfaces Coatings and Films Hysteresis chemistry hysteresis Thin-film transistor lcsh:TA1-2040 Optoelectronics 0210 nano-technology business lcsh:Engineering (General). Civil engineering (General) AND gate |
| Zdroj: | Coatings, Vol 10, Iss 1146, p 1146 (2020) Coatings Volume 10 Issue 12 |
| ISSN: | 2079-6412 |
| Popis: | In this work, two stacked gate dielectrics of Al2O3/tetraethyl-orthosilicate (TEOS) oxide were deposited by using the equivalent capacitance with 100-nm thick TEOS oxide on the patterned InGaZnO layers to evaluate the electrical characteristics and stability improvement of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) devices, including positive bias stress (PBS) and negative bias stress (NBS) tests. Three different kinds of gate dielectrics (Al2O3, TEOS, Al2O3/TEOS) were used to fabricate four types of devices, differing by the gate dielectric, as well as its thickness. As the Al2O3 thickness of Al2O3/TEOS oxide dielectric stacks increased, both the on-current and off-current decreased, and the transfer curves shifted to larger voltages. The lowest ∆Vth of 0.68 V and ∆S.S. of &minus 0.03 V/decade from hysteresis characteristics indicate that the increase of interface traps and charge trapping between the IGZO channel and gate dielectrics is effectively inhibited by using two stacked dielectrics with 10-nm thick Al2O3 and 96-nm thick TEOS oxide. The lowest ∆Vth and ∆S.S. values of a-IGZO TFTs with 10-nm thick Al2O3 and 96-nm thick TEOS oxide gate dielectrics according to the PBS and NBS tests were shown to have the best electrical stability in comparison to those with the Al2O3 or TEOS oxide single-layer dielectrics. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|