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Title: Ambipolar nonvolatile memory based on a quantum-dot transistor with a nanoscale floating gate

Abstract

Using only solution processing methods, we developed ambipolar quantum-dot (QD) transistor floating-gate memory (FGM) that uses Au nanoparticles as a floating gate. Because of the bipolarity of the active channel of PbSe QDs, the memory could easily trap holes or electrons in the floating gate by programming/erasing (P/E) operations, which could shift the threshold voltage both up and down. As a result, the memory exhibited good programmable memory characteristics: a large memory window (ΔV{sub th} ∼ 15 V) and a long retention time (>10{sup 5 }s). The magnitude of ΔV{sub th} depended on both P/E voltages and the bias voltage (V{sub DS}): ΔV{sub th} was a cubic function to V{sub P/E} and linearly depended on V{sub DS}. Therefore, this FGM based on a QD transistor is a promising alternative to its inorganic counterparts owing to its advantages of bipolarity, high mobility, low cost, and large-area production.

Authors:
; ; ; ; ;  [1];  [2];  [1];  [2];  [2];  [3];  [4]
  1. Institute of Laser and Opto-Electronics, College of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072 (China)
  2. (China)
  3. Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China)
  4. Center of Material Science, National University of Defense Technology, Changsha 410073 (China)
Publication Date:
OSTI Identifier:
22590635
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTRIC POTENTIAL; LEAD SELENIDES; MATHEMATICAL SOLUTIONS; NANOPARTICLES; QUANTUM DOTS; TRANSISTORS; TRAPS

Citation Formats

Che, Yongli, Zhang, Yating, E-mail: yating@tju.edu.cn, Song, Xiaoxian, Cao, Mingxuan, Zhang, Guizhong, Yao, Jianquan, Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072, Cao, Xiaolong, Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072, College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao 266590, Dai, Haitao, and Yang, Junbo. Ambipolar nonvolatile memory based on a quantum-dot transistor with a nanoscale floating gate. United States: N. p., 2016. Web. doi:10.1063/1.4955452.
Che, Yongli, Zhang, Yating, E-mail: yating@tju.edu.cn, Song, Xiaoxian, Cao, Mingxuan, Zhang, Guizhong, Yao, Jianquan, Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072, Cao, Xiaolong, Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072, College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao 266590, Dai, Haitao, & Yang, Junbo. Ambipolar nonvolatile memory based on a quantum-dot transistor with a nanoscale floating gate. United States. doi:10.1063/1.4955452.
Che, Yongli, Zhang, Yating, E-mail: yating@tju.edu.cn, Song, Xiaoxian, Cao, Mingxuan, Zhang, Guizhong, Yao, Jianquan, Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072, Cao, Xiaolong, Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072, College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao 266590, Dai, Haitao, and Yang, Junbo. 2016. "Ambipolar nonvolatile memory based on a quantum-dot transistor with a nanoscale floating gate". United States. doi:10.1063/1.4955452.
@article{osti_22590635,
title = {Ambipolar nonvolatile memory based on a quantum-dot transistor with a nanoscale floating gate},
author = {Che, Yongli and Zhang, Yating, E-mail: yating@tju.edu.cn and Song, Xiaoxian and Cao, Mingxuan and Zhang, Guizhong and Yao, Jianquan and Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072 and Cao, Xiaolong and Key Laboratory of Opto-Electronics Information Technology, Ministry of Education, Tianjin University, Tianjin 300072 and College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao 266590 and Dai, Haitao and Yang, Junbo},
abstractNote = {Using only solution processing methods, we developed ambipolar quantum-dot (QD) transistor floating-gate memory (FGM) that uses Au nanoparticles as a floating gate. Because of the bipolarity of the active channel of PbSe QDs, the memory could easily trap holes or electrons in the floating gate by programming/erasing (P/E) operations, which could shift the threshold voltage both up and down. As a result, the memory exhibited good programmable memory characteristics: a large memory window (ΔV{sub th} ∼ 15 V) and a long retention time (>10{sup 5 }s). The magnitude of ΔV{sub th} depended on both P/E voltages and the bias voltage (V{sub DS}): ΔV{sub th} was a cubic function to V{sub P/E} and linearly depended on V{sub DS}. Therefore, this FGM based on a QD transistor is a promising alternative to its inorganic counterparts owing to its advantages of bipolarity, high mobility, low cost, and large-area production.},
doi = {10.1063/1.4955452},
journal = {Applied Physics Letters},
number = 1,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
  • An ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory was demonstrated, with discrete distributed gold nanoparticles, tetratetracontane (TTC), pentacene as the floating-gate layer, tunneling layer, and active layer, respectively. The electron traps at the TTC/pentacene interface were significantly suppressed, which resulted in an ambipolar operation in present memory. As both electrons and holes were supplied in the channel and trapped in the floating-gate by programming/erasing operations, respectively, i.e., one type of charge carriers was used to overwrite the other, trapped, one, a large memory window, extending on both sides of the initial threshold voltage, was realized.
  • Two types of floating-gate based organic thin-film transistor nonvolatile memories (FG-OTFT-NVMs) were demonstrated, with poly(methyl methacrylate co glycidyl methacrylate) (P(MMA-GMA)) and tetratetracontane (TTC) as the tunneling layer, respectively. Their device performances were measured and compared. In the memory with a P(MMA-GMA) tunneling layer, typical unipolar hole transport was obtained with a relatively small mobility of 0.16 cm{sup 2}/V s. The unidirectional shift of turn-on voltage (V{sub on}) due to only holes trapped/detrapped in/from the floating gate resulted in a small memory window of 12.5 V at programming/erasing voltages (V{sub P}/V{sub E}) of ±100 V and a nonzero reading voltage. Benefited from the well-ordered moleculemore » orientation and the trap-free surface of TTC layer, a considerably high hole mobility of 1.7 cm{sup 2}/V s and a visible feature of electrons accumulated in channel and trapped in floating-gate were achieved in the memory with a TTC tunneling layer. High hole mobility resulted in a high on current and a large memory on/off ratio of 600 at the V{sub P}/V{sub E} of ±100 V. Both holes and electrons were injected into floating-gate and overwritten each other, which resulted in a bidirectional V{sub on} shift. As a result, an enlarged memory window of 28.6 V at the V{sub P}/V{sub E} of ±100 V and a zero reading voltage were achieved. Based on our results, a strategy is proposed to optimize FG-OTFT-NVMs by choosing a right tunneling layer to improve the majority carrier mobility and realize ambipolar carriers injecting and trapping in the floating-gate.« less
  • High-performance organic field-effect transistor nonvolatile memories have been achieved using sputtered C nanoparticles as the nano-floating-gate. The sputtered C nano-floating-gate is prepared with low-cost material and simple process, forming uniform and discrete charge trapping sites covered by a smooth and complete polystyrene layer. The devices show large memory window, excellent retention capability, and programming/reading/erasing/reading endurance. The sputtered C nano-floating-gate can effectively trap both holes and electrons, and it is demonstrated to be suitable for not only p-type but also n-type organic field-effect transistor nonvolatile memories.
  • Electron and hole trapping into the nano-floating-gate of a pentacene-based organic field-effect transistor nonvolatile memory is directly probed by Kelvin probe force microscopy. The probing is straightforward and non-destructive. The measured surface potential change can quantitatively profile the charge trapping, and the surface characterization results are in good accord with the corresponding device behavior. Both electrons and holes can be trapped into the nano-floating-gate, with a preference of electron trapping than hole trapping. The trapped charge quantity has an approximately linear relation with the programming/erasing gate bias, indicating that the charge trapping in the device is a field-controlled process.