Studies on Quantum Transport Mechanism of Si Quasi-One-Dimensional Carrier Systems by a Time-of-Flight Method with Pulse Lasers

脉冲激光飞行时间法研究Si准一维载流子系统的量子输运机制

• 批准号: 04452090
• 负责人: YASUDA Yukio
• 金额: $ 0.64万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04452090/
• 关键词: p-Si wire; 1D-VRH; negative magnetoresistance; Anderson localization; SiGe thin film; 擬1次元キャリア; 不純物伝導; 1次元ホッピング伝導; 磁気抵抗

The purpose of this work is to realize the low-dimensional carrier system in silicon and to make clear the transport mechanism in this system. We have examined the relationship between the fabrication condition of one-dimensional systems and the observed carrier transport mechanism. The life time of carriers in Si_<1-x>Ge_x/Si systems has been studied by means of the Time-of-Flight method. Si_<1-x>Ge_x/Si films are expected as a material for realizing low-dimensional systems on silicon.Electrical conductive wires of p-Si were fabricated on n-Si by FIB.The current-voltage characteristic was measured in the temperature range of 2K to 300K.Three kinds of characteristic transport can be observed ; the metallic conduction, the nearest neighbor hopping conduction, and the one dimensional variable hopping conduction. There exists a systematic relationship between the observed transport mechanism and the fabrication condition. In the experiments, it can be concluded that the transport mechanis … More m in the wire are controlled by changing the annealing temperature and the impurity dose.The information of localized states in the hopping conduction were studied with the measurements of transverse magnetoresistance. The negative magnetoresistance is observed on the sample with low impurity concentrations, for the sample with the nearest neighbor hopping conduction above 15K, which suggests the existence of Anderson localization. On the other hand, in the strong magnetic field, the positive magnetoresistance appears for all samples. The analysis of the positive magnetoresistance indicates that the localization is due to the confinement by the Coulomb potential. These facts mean the existance of two kinds of localized states.The Time of Flight method with pulse lasers was used for the study of transport phenomena in nano-scale semiconductor devices. In this experiments, undoped Si_<1-x>Ge_x thinfilms were selected as a test material. We have obtained the relationship between the carrieer life time and the amount of the defects. In conclusion, the method is useful for evaluating the life time and the localized state density. Less

这项工作的目的是在硅中实现低维载流子系统，并弄清该系统中的输运机制。我们研究了一维系统的制备条件与观察到的载流子输运机制之间的关系。用飞行时间法研究了Si_1-x&Gt；Ge_x/Si系统中载流子的寿命。Si_x；1-x&Gt；Ge_x/Si薄膜有望成为实现硅上低维系统的材料。利用FIB在n-Si衬底上制备了p-Si导电线。在2K~300K的温度范围内，测量了p-Si的电流-电压特性。观察到三种特征输运：金属导电、最近邻跳跃导电和一维可变跳跃导电。观察到的输运机制与制备条件之间存在着系统的关系。在实验中，可以得出结论，这种传输机制是…通过改变退火温度和掺杂浓度来控制导线中较多的m。通过横向磁阻测量研究了跳跃电导中局域态的信息。对于最近邻跃迁电导大于15K的样品，在低杂质浓度的样品上观察到了负磁电阻，这表明存在Anderson局域化。另一方面，在强磁场中，所有样品都出现了正磁阻。正磁阻分析表明，局域化是由于库仑势的限制。这意味着存在两种局域态。利用脉冲激光飞行时间法研究了纳米半导体器件中的输运现象。在本实验中，选择了未掺杂的Si_1-x&Gt；Ge_x薄膜作为测试材料。得到了载流子寿命与缺陷数量之间的关系。综上所述，该方法可用于估算材料的寿命和局域态密度。较少

项目成果

H.Iwano, et.al.: "Fabrication and carrier transport phenomena of one-dimensional quantum wires of p-type silicon" Journal of Vaccum Science & Technology B. Vol.11. 61-65 (1993)

H.Iwano 等人：“p 型硅一维量子线的制造和载流子传输现象”真空科学杂志

H.Iwano,et.al.: "Fabrication and carrier transport phenomena of one-dimensional quantum wires of p-type silicon" Journal of Vaccum Science & Technology B. 11. 61-65 (1993)

H.Iwano等人：“p型硅一维量子线的制造和载流子传输现象”真空科学杂志