Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film Transistors
In this study, we analyzed the threshold voltage shift characteristics of bottom-gate amorphous indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) under a wide range of positive stress voltages. We investigated four mechanisms: electron trapping at the gate insulator layer by a vertical e...
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MDPI AG
2021-03-01
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| Online Access: | https://www.mdpi.com/2072-666X/12/3/327 |
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| author | Je-Hyuk Kim Jun Tae Jang Jong-Ho Bae Sung-Jin Choi Dong Myong Kim Changwook Kim Yoon Kim Dae Hwan Kim |
| author_facet | Je-Hyuk Kim Jun Tae Jang Jong-Ho Bae Sung-Jin Choi Dong Myong Kim Changwook Kim Yoon Kim Dae Hwan Kim |
| author_sort | Je-Hyuk Kim |
| collection | DOAJ |
| description | In this study, we analyzed the threshold voltage shift characteristics of bottom-gate amorphous indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) under a wide range of positive stress voltages. We investigated four mechanisms: electron trapping at the gate insulator layer by a vertical electric field, electron trapping at the drain-side GI layer by hot-carrier injection, hole trapping at the source-side etch-stop layer by impact ionization, and donor-like state creation in the drain-side IGZO layer by a lateral electric field. To accurately analyze each mechanism, the local threshold voltages of the source and drain sides were measured by forward and reverse read-out. By using contour maps of the threshold voltage shift, we investigated which mechanism was dominant in various gate and drain stress voltage pairs. In addition, we investigated the effect of the oxygen content of the IGZO layer on the positive stress-induced threshold voltage shift. For oxygen-rich devices and oxygen-poor devices, the threshold voltage shift as well as the change in the density of states were analyzed. |
| first_indexed | 2024-03-10T13:04:56Z |
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| institution | Directory Open Access Journal |
| issn | 2072-666X |
| language | English |
| last_indexed | 2024-03-10T13:04:56Z |
| publishDate | 2021-03-01 |
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| series | Micromachines |
| spelling | doaj.art-7e2cbb278b6c404998821b8dbcea8b622023-11-21T11:11:39ZengMDPI AGMicromachines2072-666X2021-03-0112332710.3390/mi12030327Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film TransistorsJe-Hyuk Kim0Jun Tae Jang1Jong-Ho Bae2Sung-Jin Choi3Dong Myong Kim4Changwook Kim5Yoon Kim6Dae Hwan Kim7The School of Electrical Engineering, Kookmin University, Seoul 02707, KoreaThe School of Electrical Engineering, Kookmin University, Seoul 02707, KoreaThe School of Electrical Engineering, Kookmin University, Seoul 02707, KoreaThe School of Electrical Engineering, Kookmin University, Seoul 02707, KoreaThe School of Electrical Engineering, Kookmin University, Seoul 02707, KoreaCircadian ICT Research Center, Kookmin University, Seoul 02707, KoreaThe School of Electrical and Computer Engineering, University of Seoul, Seoul 02504, KoreaThe School of Electrical Engineering, Kookmin University, Seoul 02707, KoreaIn this study, we analyzed the threshold voltage shift characteristics of bottom-gate amorphous indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) under a wide range of positive stress voltages. We investigated four mechanisms: electron trapping at the gate insulator layer by a vertical electric field, electron trapping at the drain-side GI layer by hot-carrier injection, hole trapping at the source-side etch-stop layer by impact ionization, and donor-like state creation in the drain-side IGZO layer by a lateral electric field. To accurately analyze each mechanism, the local threshold voltages of the source and drain sides were measured by forward and reverse read-out. By using contour maps of the threshold voltage shift, we investigated which mechanism was dominant in various gate and drain stress voltage pairs. In addition, we investigated the effect of the oxygen content of the IGZO layer on the positive stress-induced threshold voltage shift. For oxygen-rich devices and oxygen-poor devices, the threshold voltage shift as well as the change in the density of states were analyzed.https://www.mdpi.com/2072-666X/12/3/327indium-gallium-zinc-oxide thin-film transistors (-IGZO TFT)oxygen contentinstabilityelectron trappinghole trappingdonor-like state creation |
| spellingShingle | Je-Hyuk Kim Jun Tae Jang Jong-Ho Bae Sung-Jin Choi Dong Myong Kim Changwook Kim Yoon Kim Dae Hwan Kim Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film Transistors Micromachines indium-gallium-zinc-oxide thin-film transistors (-IGZO TFT) oxygen content instability electron trapping hole trapping donor-like state creation |
| title | Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film Transistors |
| title_full | Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film Transistors |
| title_fullStr | Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film Transistors |
| title_full_unstemmed | Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film Transistors |
| title_short | Analysis of Threshold Voltage Shift for Full V<sub>GS</sub>/V<sub>DS</sub>/Oxygen-Content Span under Positive Bias Stress in Bottom-Gate Amorphous InGaZnO Thin-Film Transistors |
| title_sort | analysis of threshold voltage shift for full v sub gs sub v sub ds sub oxygen content span under positive bias stress in bottom gate amorphous ingazno thin film transistors |
| topic | indium-gallium-zinc-oxide thin-film transistors (-IGZO TFT) oxygen content instability electron trapping hole trapping donor-like state creation |
| url | https://www.mdpi.com/2072-666X/12/3/327 |
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