2017年6月1日
Measurement and potential barrier evolution analysis of cold field emission in fracture fabricated Si nanogap
Japanese Journal of Applied Physics
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- ,
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- 巻
- 56
- 号
- 6
- 開始ページ
- 06GF06
- 終了ページ
- 記述言語
- 英語
- 掲載種別
- 研究論文(国際会議プロシーディングス)
- DOI
- 10.7567/JJAP.56.06GF06
- 出版者・発行元
- Japan Society of Applied Physics
Cold field emission characteristics of a fracture fabricated Si nanogap (>
100 nm) were investigated with an ascending electric field (voltage) sweep. The nanogap was formed by controlled fracture of a free-standing silicon micro-beam along o111p direction by a microelectromechanical device, which results in flat, smooth, and conformal electrode pairs. This facilitates simultaneous large area emission, which gives rise to a significant current at low bias voltage, which usually remains indiscernible in nanogaps of this size. The measured emission current-voltage (I-V) characteristics clearly depict two distinct regimes: a linear (I / V) regime at low bias voltage and a nonlinear [ln(I/V2) / V%1] regime at high bias voltage, separated by a transition point. We propose that the linear regime is owed to direct tunneling of electrons, whereas the nonlinear regime is due to Fowler-Nordheim type emission. This proposition essentially implies that the tunneling potential barrier gradually evolved from a rectangular shape to a triangular shape with increasing field (V). This type of evolution is usually observed in molecular size gaps. We have attempted to correlate the I-V curves acquired through the experiments with the electric field induced barrier shape evolution by numerical calculations involving standard quantum mechanics. The observed linear regime at low bias voltage (<
5 V) in a relatively large size gap (>
100 nm) is attributed to the fabrication method adopted in this study. The reported study and the fabricated device are significant for developing a futuristic thermotunneling refrigerator that will find a wide range of application in nanoelectronic devices.
100 nm) were investigated with an ascending electric field (voltage) sweep. The nanogap was formed by controlled fracture of a free-standing silicon micro-beam along o111p direction by a microelectromechanical device, which results in flat, smooth, and conformal electrode pairs. This facilitates simultaneous large area emission, which gives rise to a significant current at low bias voltage, which usually remains indiscernible in nanogaps of this size. The measured emission current-voltage (I-V) characteristics clearly depict two distinct regimes: a linear (I / V) regime at low bias voltage and a nonlinear [ln(I/V2) / V%1] regime at high bias voltage, separated by a transition point. We propose that the linear regime is owed to direct tunneling of electrons, whereas the nonlinear regime is due to Fowler-Nordheim type emission. This proposition essentially implies that the tunneling potential barrier gradually evolved from a rectangular shape to a triangular shape with increasing field (V). This type of evolution is usually observed in molecular size gaps. We have attempted to correlate the I-V curves acquired through the experiments with the electric field induced barrier shape evolution by numerical calculations involving standard quantum mechanics. The observed linear regime at low bias voltage (<
5 V) in a relatively large size gap (>
100 nm) is attributed to the fabrication method adopted in this study. The reported study and the fabricated device are significant for developing a futuristic thermotunneling refrigerator that will find a wide range of application in nanoelectronic devices.
- ID情報
-
- DOI : 10.7567/JJAP.56.06GF06
- ISSN : 1347-4065
- ISSN : 0021-4922
- SCOPUS ID : 85020541062