Radiation-Hard ZnO Thin Film Transistors

Author

Ramirez, J. Israel ; Li, Yuanyuan V. ; Basantani, Hitesh ; Leedy, Kevin ; Bayraktaroglu, Burhan ; Jessen, Gregg H. ; Jackson, Thomas N.

Author_Institution

Dept. of Electr. Eng., Penn State Univ., University Park, PA, USA

Volume

62

Issue

3

fYear

2015

fDate

Jun-15

Firstpage

1399

Lastpage

1404

Abstract

We report effects for up to 100 Mrad (SiO₂) gamma-ray exposure on polycrystalline ZnO thin film transistors (TFTs) deposited by two different techniques. The radiation related TFT changes, either with or without electrical bias during irradiation, are primarily a negative VON shift and a smaller VT shift (ΔV_ON ~ - 2.5 V and ΔV_T ~ - 1.5 V for 100 Mrad (SiO₂) exposure). Field-effect mobility remains nearly unchanged. Both, VON and VT shifts are nearly completely removed by annealing at 200°C for 1 minute and some recovery is seen even at room temperature. We find that our ZnO TFTs are insensitive to electrical bias during irradiation; that is, unbiased measurements are useful worst case test results. To the best of our knowledge, these are the most radiation-hard thin film transistors reported to date.

Keywords

annealing; radiation hardening (electronics); silicon compounds; thin film transistors; zinc compounds; SiO₂; ZnO; annealing; electrical bias; gamma-ray exposure; polycrystalline TFT; radiation-hard thin film transistors; temperature 200 degC; temperature 293 K to 298 K; time 1 min; Annealing; Logic gates; Radiation effects; Silicon; Thin film transistors; Threshold voltage; Zinc oxide; Cobalt-60; ZnO; gamma rays; irradiation; oxide semiconductor; polycrystalline ZnO; radiation-hard; thin film transistors (TFTs);

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/TNS.2015.2417831

Filename

7100947