Photoluminescence Characteristics of Size-controlled Germanium Nanoparticles-Film

尺寸控制的纳米锗粒子薄膜的光致发光特性

• 批准号: 12650677
• 负责人: IWAMA Saburo
• 金额: $ 0.64万
• 依托单位: DAIDO INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650677/
• 关键词: Flowing Gas Evaporation Method; Germanium nanoparticles; Tetragonal Structure; Particle-Size Control; Photoluminescence Characteristics; Amorphous Structure; FGE法; アモルファス構造

Germanium nanoparticles were produced by the Flowing Gas Evaporation Method, where Ge was evaporated from the tungsten hot filament in a low He or Ar gas pressure with a high gas velocity. From the X-ray diffraction analysis of the systematically produced Ge-nanoparticles, the following results on crystal structure and the mean particle size were obtained. (1) Three kinds of structure of amorphous, diamond and tetragonal were formed depending on conditions of the gas pressure and the gas velocity. The amorphous Ge-nanoparticles were formed under the He gas conditions, that is, the pressure was below 0.3Torr and the velocity was over 20m/s. The most frequent formation of tetragonal Ge-nanoparticles was under the He conditions, where the gas pressure is from 1,0 to 2.0Torr and the gas velocity is from 0.3 to 20m/s, though the tetragonal structure was always found in the mixture with the diamond structure. Out of the He gas conditions mentioned above, Ge-nanoparticles with the ordinary diamond structure was formed. (2) The lattice parameters of the tetragonal structure was determined to be a = 0.538nm and c = 0.879nm from the X-ray diffraction measurement. These values are different from those of already observed in the high-pressure form. And also the c-parameter in the present case is smaller by about 3% than that of Ge-nanoparticles formed by the ordinary Gas Evaporation Technique. It is considered that the tetragonal structure formed in the present study is a new structure of germanium. (3) Photoluminescence measurements of both specimens of Ge-nanoparticles with diamond structure and with mixed structure of diamond and tetragonal showed the similar broad spectra in infrared region with the peak near 1550nm. The real peak may be in much longer wavelength, where it cannot be measured in the present setup because of the weakness of the detector.

锗纳米颗粒是通过流动气体蒸发法制备的，其中Ge在低He或Ar气体压力下以高气体速度从钨热灯丝蒸发。从系统生产的Ge纳米颗粒的X射线衍射分析，获得了以下关于晶体结构和平均粒度的结果。(1)根据气体压力和气体流速的不同，形成了非晶、金刚石和四方晶三种结构。非晶态Ge纳米颗粒在He气体条件下形成，即压力低于0.3Torr，速度超过20 m/s。最常见的形成的tetraxylGe-纳米颗粒是在He条件下，其中气体压力是从1.0到2.0Torr和气体速度是从0.3到20 m/s，虽然tetraxylGe结构总是在与金刚石结构的混合物中被发现。在上述He气体条件之外，形成具有普通金刚石结构的Ge纳米颗粒。(2)通过X射线衍射测定了该配合物的晶胞参数a = 0.538nm，c = 0.879nm。这些数值与已经在高压形式下观察到的数值不同。并且在本情况下的c参数也比通过普通气体蒸发技术形成的Ge纳米颗粒的c参数小约3%。认为本研究中形成的四配位结构是锗的一种新结构。(3)对金刚石结构和金刚石与四氢化锗混合结构的Ge纳米颗粒样品的光致发光测量表明，在1550 nm附近有一个类似的红外宽光谱。真实的峰值可能在更长的波长中，其中由于检测器的弱点而不能在当前设置中测量。

项目成果

K. Tanaka and S. Iwama: "Crystal Structure and Particle Size of Ge-Nanoparticles Depending on the Flowing Gas Evaporation Conditions"Transactions of the Materials Research Society of Japan. (in printing in March). (2002)

K. Tanaka 和 S. Iwama：“Ge 纳米粒子的晶体结构和粒径取决于流动气体蒸发条件”日本材料研究学会会刊。

K.Tanaka, S.Iwama: "Crystal Structure and Particle Size of Ge-Nanoparticles Depending on the Flowing Gas Evaporation Conditions"Transactions of the Materials Research Society of Japan. (in printing). (2002)

K.Tanaka、S.Iwama：“Ge 纳米粒子的晶体结构和粒径取决于流动气体蒸发条件”日本材料研究学会会刊。