Behavior of hot-electron at MIM tunnel junction/porous Si interface

MIM 隧道结/多孔硅界面处的热电子行为

• 批准号: 12450254
• 负责人: HATTA Aritada
• 金额: $ 9.6万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450254/
• 关键词: hot-electron; tunnel junction; I-V property; Ag; AlO_x; Al; porous-Si substrate; glass substrate; 2Methyl-1, 4Naphtoquinone; IRRAS; Cu; 一酸化炭素; 高感度反射赤外分光; MIM; ポーラスSi; ナフトキノン; A10x; エレクトロルミネセンス; STM

When a sufficiently strong voltage but not beyond the metal work function is applied across an Al/AlO_x/Ag junction, the so-called "hot-electron" whose energy is higher than the Fermi level can be generated. In this study, we aimed to establish the method of fabrication of Al/AlO_x/Ag junctions and to obtain basic knowledge concerning the behavior of hot electrons at the interface between the tunnel junction and the porous-Si substrate through measurements of the I-V curve. Further, the change in chemical species on Ag electrode surface during a bias voltage was applied across the junction was investigated with IR reflection absorption spectroscopy. The results obtained are summarized as follows.(1)A matter of the utmost importance in preparation of the Al/AlO_x/Ag tunnel junction is to establish the oxidation conditions of Al thin film electrode. The oxidation of the Al electrode at 280℃, 2 hours in oxygen (1 atm) atmosphere, or at 450℃, several minutes in air was suitable to obtain the junction.(2)Under irradiation of 441.6nm He-Cd laser (80mW), a remarkable increase in the tunnel current was observed for the junction formed on porous-Si substrate, whereas the junction formed on glass substrate showed no change in the tunnel current even though the same irradiation conditions were employed. The band-gap of the porous-Si used in the present study was about 1.6 eV and hence the photo-voltage generated at the porous-Is might influence the tunneling properties of the junction through the change in charge distribution between the Al electrode and the porous-Si substrate.(3)The decomposition of a 2Methyl-1, 4Naphtoquinone thin film formed on the junction was promoted when applying the bias voltage (+) to the Al electrode.

当在 Al/AlO_x/Ag 结上施加足够强但不超过金属功函数的电压时，可以产生能量高于费米能级的所谓“热电子”。建立Al/AlO_x/Ag结的制造方法，并通过I-V曲线的测量获得有关隧道结和多孔硅衬底之间界面处热电子行为的基本知识。物种通过红外反射吸收光谱研究了在结施加偏压期间Ag电极表面的变化。所得结果总结如下。(1)Al/AlO_x/Ag隧道结制备中最重要的问题是。建立Al薄膜电极的氧化条件，Al电极在氧气（1 atm）气氛中280℃氧化2小时，或在空气中450℃氧化几分钟，以获得合适的氧化效果。 (2)在441.6nm He-Cd激光(80mW)照射下，在多孔Si衬底上形成的结观察到隧道电流显着增加，而在玻璃衬底上形成的结则隧道电流没有变化。即使采用相同的照射条件，本研究中使用的多孔硅的带隙约为 1.6 eV，因此多孔硅处产生的光电压可能会影响。通过改变Al电极和多孔Si衬底之间的电荷分布来改变结的隧道特性。(3)当施加偏压(+ ）到铝电极。