Bi-Sb-Te基热电薄膜温差电池离子束溅射制备与表征

本文采用离子束溅射Bi/Te和Sb/Te二元复合靶,直接制备n型Bi₂Te₃热电薄膜和p型Sb₂Te₃热电薄膜.在退火时间同为1 h的条件下,对所制备的Bi₂Te₃薄膜和Sb₂Te₃薄膜进行不同温度的退火处理,并对其热电性能进行表征.结果表明,在退火温度为150 ℃时,制备的n型Bi₂Te₃关键词： 薄膜温差电池 2Te₃薄膜')" href="#">Sb₂Te₃薄膜 2Te₃薄膜')" href="#">Bi₂Te₃薄膜 离子束溅射     

Growth and Characterization of CIS Thin Films Prepared by Ion Beam Sputtering Deposition

Copper indium diselenide （CuInSe2） thin films were prepared by ion beam sputtering Cu, In and Se targets continuously on BK7 glass substrates and the three-layer film was then annealed in the same vacuum chamber. X-ray diffraction shows that the CuInSe2 thin films have a single chalcopyrite structure with preferential （112） orientation. Scanning electron microscopy reveals that the CIS thin films consist of uniform and densely packed grain clusters. Energy dispersive x-ray spectroscopy demonstrates that the elemental composition of CIS films approaches the stochiometric composition ratios of 1：1：2. Raman measurement shows that the main peak is at about 174cm^-1 and this peak is identified as the A1 vibrational mode from chaicopyrite ordered CulnSe2. Optical transmission and absorption spectroscopy measurement reveal an energy band gap of about 1.05 eV and an absorption coefficient of 10^5 cm^-1. The film resistivity is about 0.01 Ωcm.     

Composition-Dependent Characterization of Sb2Te3 Thin Films Prepared by Ion Beam Sputtering Deposition

The optimization of ion beam sputtering deposition process for Sb2 Te3 thin films deposited on BK7 glass substrates is reported. The influence of composition ratio on the thermoelectric properties is investigated. X-ray diffraction shows that the major diffraction peaks of the films match with those of Sb2 Te3. Hall effect and Seebeck coefficient measurement reveal that all the samples are of p-type. The Sb2 Te3 thin films exhibit the Seebeck coefficient of 190μVk^-1 and the electrical conductivity of 1.1 × 10^3 Scm^-1 when the atomic ratio of Sb to Te is 0.65. Carrier concentration and motility of the films increase with the increasing atomic ratio of Sb to Te. The Sb2 Tea film with a maximum power factor of 2.26×10^-3 Win^-1K^-2 is achieved when annealed at 400℃. Raman measurement shows that the main peaks are at about 120 cm^-1, 252 cm^-1 and 450 cm^-1, in agreement with those of V-VI compound semiconductors.     

Sb_2Te_3热电薄膜的离子束溅射制备与表征

采用离子束溅射技术交替沉积Sb-Te-Sb多层薄膜后进行高真空热处理,直接制备Sb2Te3薄膜.利用X射线衍射(XRD)仪、霍尔系数测试仪、薄膜Seebeck系数测量系统对所制备的薄膜特性进行表征.XRD测量结果显示,薄膜的主要衍射峰与Sb2Te3标准衍射峰相同,在[101]/[012]晶向取向明显,存在较多的Te杂质峰;霍尔系数测试结果表明,薄膜为p型半导体薄膜,薄膜电阻率较低,其电导率接近于金属电导率,载流子浓度量级为1023cm-3,具有良好的电学性能;Seebeck系数测量结果显示,薄膜具有良好的热电性能,在不同条件下制备的薄膜的Seebeck系数在7.8—62μV/K范围;在所制备的薄膜中,退火时间为6h、退火温度为200℃的薄膜其Seebeck系数达到最大,约为62μV/K,且电阻率最小.     

InN纳米线的低压化学气相沉积及其场发射特性研究

利用低压化学气相沉积方法在以Au作催化剂的Si衬底上生长了InN纳米线. 扫描电子显微镜分析表明，这些纳米线的直径在60—100 nm的范围内, 而其长度大于1 μm.高分辨透射电子显微镜图像表明，合成的纳米线中含有六方相和立方相的InN晶体.这些InN纳米线具有良好的场发射特性和稳定的场发射电流，其开启场为10.02 V/μm(电流密度为10 μA/cm²)，在24 V/μm 的电场下，其电流密度达到5.5 mA/cm².此外，对InN纳米线的场发射机理也进行了讨论. 关键词： InN纳米线 场电子发射 非线性Fower-Nordheim曲线     

利用量纲分析从弹簧振子的能量直接推导单摆的能量

水平放置的弹簧振子是有关教材中讲解简谐运动的常用例子,该系统具有弹性势能和动能,其能量随时间及振幅变化的特点常被用于代表简谐振动。单摆是另外一种作简谐振动的例子,单摆具有重力势能和动能,从弹簧振子的能量公式并不能直接导出单摆的动能及势能等表示式。为解决这一问题,本文从弹簧振子的能量表示式出发,根据量纲分析,推导出了作简谐运动的单摆的能量表示式。对比利用量纲分析得到的结果与直接从单摆计算得到的结果,可以发现它们完全一致。