AJP由EPSRC软纳米技术平台赠款EP/E046215/1提供资金。中子实验由STFC通过分配实验时间来使用 OffSpec （RB 1110285） 来支持。

1. 样品准备
<ol><li>将2个4毫米厚的硅晶片放入氧气等离子体中，清洁硅基板10分钟。</li>
	<li>在基材上涂上第一层<ol>
<li>通过 0.45μm PTFE 过滤器 （PALL） 过滤聚聚物 （3，4-乙烯二硫苯）： 聚 （苯硫酸酯） （PEDOT：PSS）。</li>
		<li>每个样品使用约 0.5 毫升，在 5，000 rpm 旋转 60 秒时将 PEDOT：PSS 薄膜旋转到两个干净的基材上。</li>
		<li>在 70 °C 的烤箱中干燥每个基板 10 分钟。</li>
	</ol>
</li>
	<li>为第二层准备混合解决方案<ol>
<li>溶解氯苯中的一些聚（3-六甲苯-2，5-二甲苯）（P3HT），浓度为50毫克/毫升。</li>
		<li>在浓度为 50 毫克/毫升的氯苯中准备 PCBM 溶液。</li>
		<li>将两种解决方案按 1：0.7 P3HT：PCBM 的比例混合。</li>
		<li>通过 0.45μm PTFE 过滤器过滤混合溶液。</li>
	</ol>
</li>
	<li>Spincoat 第二层将大约 100μl 的 P3HT：PCBM 溶液沉积到 PEDOT：PSS 涂层基材上，然后以 2，000 rpm 的速度旋转 30 秒，形成第二层。</li>
	<li>将一个样品作为铸件，在烤箱中以 150 °C 的速度将另一个样品热退火 1 小时。这导致薄膜表面的大型PCBM晶体的生长。</li>
</ol>2. 显微镜的样本特征
<ol><li>光学显微镜<ol>
<li>使用 40X 显微镜目标在反射模式下运行的光学显微镜上拍摄两个样本的光学显微镜图像，使用 CCD 摄像机捕捉图像。</li>
		<li>以步骤 2.1.1 所用的相同放大倍数记录已知长度样本的校准图像</li>
		<li>通过确定已知大小样本的像素数来计算图像的微米像素大小。</li>
		<li>使用此知道像素大小使用任何现成的显微镜软件校准图像。 图1中显示了校准光学显微镜图像的示例。</li>
	</ol>
</li>
	<li>原子力显微镜<ol>
<li>拍摄两个样本的原子力显微镜 （AFM） 图像。</li>
		<li>使用任何现成的扫描探头软件分析数据，生成行配置文件数字，如 图 1中显示的数字。</li>
	</ol>
</li>
</ol>3. 塞尔吉斯实验
<ol><li>选择合适的参考样本，提供参考极化 P0，使从兴趣数据样本中获得的数据正常化。</li>
	<li>对齐样本和参考样本<ol>
<li>将所有三个样品放在定位台上;这可以通过中子束转换，以便每个样本可以依次放置在光束中。</li>
		<li>通过翻译样品表，将 P0 参考样品放置在光束中。</li>
		<li>使用标准反射对齐方法将 P0 参考样本对齐到<0.005° 的角精度。</li>
		<li>通过翻译样品表，将感兴趣的样品放在中子束中。</li>
		<li>使用标准反射对齐方法，将感兴趣的样本与<0.005°的角精度对齐。</li>
		<li>重复此对齐过程，以测量所有感兴趣的样本。</li>
	</ol></li>
	<li>调谐 SERGIS 仪器，使其处于回声模式<ol>
<li>在 ISIS 脉冲中子和 Muon 源（英国牛津郡）设置专用的离谱反射计 OffSpec，以产生 2-14 + 的波长。使用设置的进一步细节可以在这里找到10。</li>
		<li>通过扫描导场排列的一部分电流，调整仪器以平衡仪器每个臂上的中子预置总数。这是通过在仪器的编码臂内设置磁场的强度和倾斜来实现的，磁场是由RF旋转翻转器之间的距离定义的。</li>
	</ol></li>
	<li>通过倾斜样品表设置放牧发生率的角度，使中子束在 P0 样本上发生事故（此实验的角度为 0.3°）。</li>
	<li>阻止直接传输的中子束到达探测器，以防止饱和问题。</li>
	<li>测量样本<ol>
<li>移动样品转换阶段，使参考样品再次位于中子束中，并测量分散的中子强度，作为参考样品垂直定向线性闪烁器探测器上的位置函数。通过在分析仪前翻转散射光束的旋转来测量旋转和向下旋转方向。通常，这大约需要 1 小时。这使偏振能够确定，以及两种设置的分散强度。</li>
		<li>翻译样品阶段，以测量感兴趣的第一个样本，再次记录旋转和向下旋转方向作为位置的函数，使用垂直方向的线性闪烁器探测器，持续约1小时。</li>
		<li>重复步骤 3.6.1 和 3.6.2，直到获得足够好的计数统计结果。通常这总共大约是 8 小时/样本。</li>
		<li>对于需要测量的任何进一步样本，重复步骤 3.6.1-3.6.3。</li>
	</ol></li>
	<li>收集的数据包括每个样本的旋转和向下旋转 2D 强度地图。使用公式计算 2D 数据集中每个像素的极化 <img alt="" height="51" src="/files/ftp_upload/51129/51129_3.7_equation.png" width="103"> 其中P是极化和我向上和我下来是测量旋转向上和旋转下来的特性分别。</li>
	<li>使用收集的 P0 参考样本数据对为感兴趣的样本获取的数据集正常化，根据公式生成规范化极化强度图 <img alt="" height="49" src="/files/ftp_upload/51129/51129_3.8_equation.png" width="116"> 其中P规范化是确定的极化计算，P样本 是样品极化值，P0 是使用P0 参考样本测量的极化。</li>
	<li>在适当的范围内集成 SERGIS 数据<ol>
<li>选择区域（即 规范化极化图中的像素范围）用于 SERGIS 数据集成。应选择此区域，以避免因现场线积分不完美而导致的任何潜在极化异构，从而淹没所需的 SERGIS 信号。SERGIS 信号可能集成在任何给定的自旋回声长度配置中，可用的 Q 空间实际上仅限于一系列离散的 Q 值，其中 Q 是动量传输载体 ，即 与样本交互后中子动量的变化</li>
		<li>通过整合规范化极化以获得之前定义的 SERGIS 相关函数 G（y） 来减少2D数据。严格G（y）应集成到与y垂直的两个Q矢量的无穷大，但是，出于实验原因，集成区域仅限于样本视界上方选定的检测强度。</li>
	</ol></li>
	<li>通过以类似的方式处理数据，以类似的方式通过绘制形式数据来回响小角度中子散射数据，从而补偿不同波长的不同散射长度密度： <img alt="" height="65" src="/files/ftp_upload/51129/51129_3.10_equation.png" width="127"> 其中λ是nm的自旋回波长度，可以很容易地使用y =αλ 2计算，其中α是一个恒定的使用校准常数为给定的仪器设置11。</li>
</ol>

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作者罗伯特·达尔格利什是ISIS脉冲中子和Muon源的雇员，该中子和Muon源是本实验中使用的仪器的主机。

图1中的显微镜数据清楚地表明，在使P3HT：PCBM薄膜退化之前是平坦光滑的，热退化后，表面存在许多大型不规则的PCBM晶体，横向尺寸在1-10微米之间。这归因于 PCBM 向薄膜顶部表面的迁移，以及随后的聚合以形成大型晶体。在图4中可以看到与从已分离样品中的PCBM晶体散射相关的强SERGIS信号。如果以类似微星稀释溶液的自旋回声小角度中子散射数据来考虑数据，则 SERGIS 实...

SERGIS 技术旨在利用薄膜样品的其他散射或显微技术，产生无法获取的独特结构信息。显微镜技术通常表面有限或需要重大改变/样品准备才能查看内部结构。传统的散射技术，如反射率，可以提供关于埋藏样品结构的详细信息，作为薄膜内部的深度函数，但不能轻易探测薄膜平面中的结构。最终，希望SERGIS能够探测到这种横向结构，即使埋在薄膜样品中。此处介绍的代表性结果表明，可以观察来自不规则样本特征的 SERGIS 信号，测量的信号可以与样本中所示特征相关的特征长度比例相关联，传统显微镜技术证实了这一点。
弹性自旋回声技术是由梅泽等人开发的。1在 20 世纪 70 年代。从那时起，SERGIS技术（这是Mezei等人思想的延伸）已经成功地证明使用各种样品，如高度定期衍射光栅2-6 和圆形脱湿聚合物液滴7。Pynn和同事已经开发出一种动态理论，以模拟从高度常规样本3-6，8中散射的强散射。这项工作突出了在进行这种测量时需要考虑的许多实际方面，并导致在一个小的多国社区内不断进行对话。
如果测量的样本由扁平基板上的薄膜组成，并包含散射特征，其密度为中等密度（30纳米至5微米），从而强烈散射中子，则最有可能获得SERGIS实验的良好结果，如作者9所示。与其他将样品作为深度函数探测的既定反射技术不同，SERGIS 技术具有探测样品表面平面结构的优势。此外，使用自旋回波可消除紧密结合中子束以获得高空间或能量分辨率的要求，因此可以实现显著的通量增益。这对于放牧发生几何形状特别相关，因为需要在一个方向上强力地协调光束，因此变化非常有限。因此，使用 OffSpec 仪器，应该可以在散装和表面结构中探测从 30 nm 到 5 μm 的长度尺度。

<table border="0" cellpadding="0" cellspacing="0" width="605">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Silicon 2 in silicon substrates</td>
			<td style="width:103px;">Prolog</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">4 mm thick polished one side</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Oxygen plasma</td>
			<td style="width:103px;">Diener</td>
			<td style="width:119px;"></td>
			<td>Oxygen plasma cleaning system to clean substrates prior to coating</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate)</td>
			<td style="width:103px;">Ossila</td>
			<td style="width:119px;"></td>
			<td>PEDOT:PSS conductive polymer layer for organic photovoltaic samples</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.45 &#956;m PTFE filter</td>
			<td style="width:103px;">Sigma Aldrich</td>
			<td style="width:119px;"></td>
			<td>Filer to remove aggregates from PEDOT:PSS and P3HT solutions</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Chlorobenzene</td>
			<td style="width:103px;">Sigma Aldrich</td>
			<td style="width:119px;"></td>
			<td>Solvent for P3HT</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Poly(3-hexylthiophene-2,5-diyl)</td>
			<td style="width:103px;">Ossila</td>
			<td style="width:119px;"></td>
			<td>P3HT - polymer used in polymer photovoltaics</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Spin Coater</td>
			<td style="width:103px;">Laurell</td>
			<td style="width:119px;"></td>
			<td>Deposition system for making flat thin polymer films</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Vacuum Oven</td>
			<td style="width:103px;">Binder</td>
			<td style="width:119px;"></td>
			<td>Oven fro annealing samples after preparation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Nikon Eclipse E600 optical microscope</td>
			<td style="width:103px;">Nikon</td>
			<td style="width:119px;"></td>
			<td>Microscope</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Veeco Dimension 3100 AFM</td>
			<td style="width:103px;">Veeco</td>
			<td style="width:119px;"></td>
			<td>AFM</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tapping mode tips (~275 kHz)</td>
			<td style="width:103px;">Olympus</td>
			<td style="width:119px;"></td>
			<td>AFM tips</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Quartz Disc</td>
			<td style="width:103px;"></td>
			<td style="width:119px;"></td>
			<td>Refrence samples for SERGIS measurement</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Spin Echo off-specular reflectometer</td>
			<td colspan="2">OffSpec at the ISIS Pulsed Neutron and Muon Source (Oxfordshire, UK)</td>
			<td>Produces pulsed neutrons 2-14 &#197;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Neutron Detector</td>
			<td style="width:103px;">Offspec</td>
			<td style="width:119px;"></td>
			<td>vertically oriented linear scintillator detector</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RF spin flippers</td>
			<td style="width:103px;">Offspec</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Magnetic Field Guides</td>
			<td style="width:103px;">Offspec</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Data Manipulation Software</td>
			<td style="width:103px;">Mantid</td>
			<td style="width:119px;"></td>
			<td><a href="http://www.mantidproject.org/Main_Page">http://www.mantidproject.org/Main_Page</a></td>
		</tr>
	</tbody>
</table>

using neutron spin echo resolved grazing incidence scattering to investigate organic solar cell materials

自旋回声解决放牧发生率散射 （SERGIS） 技术已用于探测与形状不规则的晶体相关的长度尺度。中子通过两个定义明确的磁场区域：一个在样品之前和之后。两个磁场区域具有相反的极性，并且经过调整，因此，在不受到干扰的情况下，中子在两个区域中飞行时，将经历相同数量的朝对方向的预兆。在这种情况下，第二臂的中子预感据说是第一个"回波"的，并且保留了束的原始极化。如果中子与样品相互作用并弹性散射，则穿过第二个手臂的路径与第一个手臂不同，并且原始极化不会恢复。中子束的去极化是一个高度敏感的探测器，角度非常小（<50μrad），但仍允许使用高强度、发散的光束。与参考样本相比，从样品反射的光束偏振程度的降低可能与样品内的结构直接相关。
与中子反射测量中观察到的散射相比，SERGIS信号通常较弱，如果被调查样本中的平面结构稀释、无序、体积小、多散射或中子散射对比度低，则不太可能观测到。因此，如果测量的样本由扁平基板上的薄膜组成，并包含包含中等尺寸特征（30 nm 至 5 μm）的高密度（30 nm 至 5 μm），从而强烈散射中子或将特征排列在晶格上，则极有可能获得良好的结果。SERGIS 技术的一个优点是它可以探测样品平面中的结构。

这里展示的 [6，6] - 苯-C61-丁酸甲基酯 （PCBM） 和聚 （3-六甲基二苯-2，5-二甲基） （P3HT） 样本具有显著意义，因为它们在有机光伏细胞12，13中广泛应用为散装异质结材料。通常，在有机光伏装置的制造过程中，P3HT：PCBM 混合溶液由混合溶液旋转铸造，在聚聚（3，4-乙二氧二苯）:p溶胶（苯硫酸酯）（PEDOT：PSS）涂层透明阳极（通常为氧化钛）上形成薄膜。然后，产生的薄膜涂在金属层中?...

Watch this Scientific Journal Video about Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials at JoVE.com

Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials

利用自旋回声解决放牧发生率散射（SERGIS）作为中子散射技术，探测不规则样品的长度尺度方面取得了进展。使用SERGIS技术对[6，6]-苯-C61-丁酸甲基酯的晶体进行了探测，结果经光学和原子力显微镜确认。

使用中子自旋回声解决放牧发生率散射调查有机太阳能电池材料

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped ...

using-neutron-spin-echo-resolved-grazing-incidence-scattering-to

Research

JoVE Journal

Engineering

6.5K 次观看.  University of Sheffield. 利用自旋回声解决放牧发生率散射（SERGIS）作为中子散射技术，探测不规则样品的长度尺度方面取得了进展。使用SERGIS技术对[6，6]-苯-C61-丁酸甲基酯的晶体进行了探测，结果经光学和原子力显微镜确认。

视频: Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials

Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures

The physical properties of a material are defined by its electronic structure. Electrons in solids are characterized by energy (&omega;) and momentum (k) and the probability to find them in a particular state with given &omega; and k is described by the spectral function A(k, &omega;). This function can be directly measured in an experiment based on the well-known photoelectric effect, for the explanation of which Albert Einstein received the Nobel Prize back in 1921. In the photoelectric effect the light shone on a surface ejects electrons from the material. According to Einstein, energy conservation allows one to determine the energy of an electron inside the sample, provided the energy of the light photon and kinetic energy of the outgoing photoelectron are known. Momentum conservation makes it also possible to estimate k relating it to the momentum of the photoelectron by measuring the angle at which the photoelectron left the surface. The modern version of this technique is called Angle-Resolved Photoemission Spectroscopy (ARPES) and exploits both conservation laws in order to determine the electronic structure, i.e. energy and momentum of electrons inside the solid. In order to resolve the details crucial for understanding the topical problems of condensed matter physics, three quantities need to be minimized: uncertainty* in photon energy, uncertainty in kinetic energy of photoelectrons and temperature of the sample.
In our approach we combine three recent achievements in the field of synchrotron radiation, surface science and cryogenics. We use synchrotron radiation with tunable photon energy contributing an uncertainty of the order of 1 meV, an electron energy analyzer which detects the kinetic energies with a precision of the order of 1 meV and a He3 cryostat which allows us to keep the temperature of the sample below 1 K. We discuss the exemplary results obtained on single crystals of Sr2RuO4 and some other materials. The electronic structure of this material can be determined with an unprecedented clarity.

The overall goal of this method is to determine the low-energy electronic structure of solids at ultra-low temperatures using Angle-Resolved Photoemission Spectroscopy with synchrotron radiation.

在极低的温度下角分辨光电子能谱

The physical properties of a material are defined by its  electronic structure. Electrons in solids are characterized by energy (&omega;)  and momentum ...

科研

工程学

Concurrent Quantitative Conductivity and Mechanical Properties Measurements of Organic Photovoltaic Materials using AFM

Organic photovoltaic (OPV) materials are inherently inhomogeneous at the nanometer scale. Nanoscale inhomogeneity of OPV materials affects performance of photovoltaic devices. Thus, understanding of spatial variations in composition as well as electrical properties of OPV materials is of paramount importance for moving PV technology forward.1,2 In this paper, we describe a protocol for quantitative measurements of electrical and mechanical properties of OPV materials with sub-100 nm resolution. Currently, materials properties measurements performed using commercially available AFM-based techniques (PeakForce, conductive AFM) generally provide only qualitative information. The values for resistance as well as Young's modulus measured using our method on the prototypical ITO/PEDOT:PSS/P3HT:PC61BM system correspond well with literature data. The P3HT:PC61BM blend separates onto PC61BM-rich and P3HT-rich domains. Mechanical properties of PC61BM-rich and P3HT-rich domains are different, which allows for domain attribution on the surface of the film. Importantly, combining mechanical and electrical data allows for correlation of the domain structure on the surface of the film with electrical properties variation measured through the thickness of the film.

Organic photovoltaic (OPV) materials are inherently inhomogeneous at the nanometer scale. Nanoscale inhomogeneity of OPV materials affects performance of photovoltaic devices. In this paper, we describe a protocol for quantitative measurements of electrical and mechanical properties of OPV materials with sub-100 nm resolution.

并行定量的导电性和力学性能测试的有机光伏材料利用原子力显微镜

Organic photovoltaic  (OPV) materials are inherently inhomogeneous at the nanometer scale. Nanoscale  inhomogeneity of OPV materials affects performance ...

Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is presented. The SANS shear cell consists of a concentric cylinder Couette geometry that is sealed and rotating about a horizontal axis so that the vorticity direction of the flow field is aligned with the neutron beam enabling scattering from the 1-2 plane of shear (velocity-velocity gradient, respectively). This approach is an advance over previous shear cell sample environments as there is a strong coupling between the bulk rheology and microstructural features in the 1-2 plane of shear. Flow-instabilities, such as shear banding, can also be studied by spatially resolved measurements. This is accomplished in this sample environment by using a narrow aperture for the neutron beam and scanning along the velocity gradient direction. Time resolved experiments, such as flow start-ups and large amplitude oscillatory shear flow are also possible by synchronization of the shear motion and time-resolved detection of scattered neutrons. Representative results using the methods outlined here demonstrate the useful nature of spatial resolution for measuring the microstructure of a wormlike micelle solution that exhibits shear banding, a phenomenon that can only be investigated by resolving the structure along the velocity gradient direction. Finally, potential improvements to the current design are discussed along with suggestions for supplementary experiments as motivation for future experiments on a broad range of complex fluids in a variety of shear motions.

A shear cell is developed for small-angle neutron scattering measurements in the velocity-velocity gradient plane of shear and is used to characterize complex fluids. Spatially resolved measurements in the velocity gradient direction are possible for studying shear-banding materials. Applications include investigations of colloidal dispersions, polymer solutions, and self-assembled structures.

测量材料在微流使用1-2面流小角中子散射

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is ...

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric vehicles.1,2 However, many challenges, such as energy density and battery lifetimes, need to be overcome before this particular battery technology can be widely implemented in such applications.3 This research is challenging, and we outline a method to address these challenges using in situ NPD to probe the crystal structure of electrodes undergoing electrochemical cycling (charge/discharge) in a battery. NPD data help determine the underlying structural mechanism responsible for a range of electrode properties, and this information can direct the development of better electrodes and batteries.
We briefly review six types of battery designs custom-made for NPD experiments and detail the method to construct the &#8216;roll-over&#8217; cell that we have successfully used on the high-intensity NPD instrument, WOMBAT, at the Australian Nuclear Science and Technology Organisation (ANSTO). The design considerations and materials used for cell construction are discussed in conjunction with aspects of the actual in situ NPD experiment and initial directions are presented on how to analyze such complex in situ data.

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

We describe the design and construction of an electrochemical cell for the examination of electrode materials using in situ neutron powder diffraction (NPD). We briefly comment on alternate in situ NPD cell designs and discuss methods for the analysis of the corresponding in situ NPD data produced using this cell.

原位中子衍射用特制的锂离子电池

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric ...

Using Synchrotron Radiation Microtomography to Investigate Multi-scale Three-dimensional Microelectronic Packages

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data acquisition times with high spatial resolution. In the electronics industry there is serious interest in performing failure analysis on 3D microelectronic packages, many which contain multiple levels of high-density interconnections. Often in tomography there is a trade-off between image resolution and the volume of a sample that can be imaged. This inverse relationship limits the usefulness of conventional computed tomography (CT) systems since a microelectronic package is often large in cross sectional area 100-3,600 mm2, but has important features on the micron scale. The micro-tomography beamline at the Advanced Light Source (ALS), in Berkeley, CA USA, has a setup which is adaptable and can be tailored to a sample&#39;s properties, i.e., density, thickness, etc., with a maximum allowable cross-section of 36 x 36 mm. This setup also has the option of being either monochromatic in the energy range ~7-43 keV or operating with maximum flux in white light mode using a polychromatic beam. Presented here are details of the experimental steps taken to image an entire 16 x 16 mm system within a package, in order to obtain 3D images of the system with a spatial resolution of 8.7 &#181;m all within a scan time of less than 3 min. Also shown are results from packages scanned in different orientations and a sectioned package for higher resolution imaging. In contrast a conventional CT system would take hours to record data with potentially poorer resolution. Indeed, the ratio of field-of-view to throughput time is much higher when using the synchrotron radiation tomography setup. The description below of the experimental setup can be implemented and adapted for use with many other multi-materials.

For this study synchrotron radiation micro-tomography, a non-destructive three-dimensional imaging technique, is employed to investigate an entire microelectronic package with a cross-sectional area of 16 x 16 mm. Due to the synchrotron&#39;s high flux and brightness the sample was imaged in just 3 min&#160;with an 8.7 &#181;m spatial resolution.

利用同步辐射微断层调查的多尺度三维微电子封装

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data ...

Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity

A method for investigating recombination dynamics of photo-induced charge carriers in thin film semiconductors, specifically in photovoltaic materials such as organo-lead halide perovskites is presented. The perovskite film thickness and absorption coefficient are initially characterized by profilometry and UV-VIS absorption spectroscopy. Calibration of both laser power and cavity sensitivity is described in detail. A protocol for performing Flash-photolysis Time Resolved Microwave Conductivity (TRMC) experiments, a non-contact method of determining the conductivity of a material, is presented. A process for identifying the real and imaginary components of the complex conductivity by performing TRMC as a function of microwave frequency is given. Charge carrier dynamics are determined under different excitation regimes (including both power and wavelength). Techniques for distinguishing between direct and trap-mediated decay processes are presented and discussed. Results are modelled and interpreted with reference to a general kinetic model of photoinduced charge carriers in a semiconductor. The techniques described are applicable to a wide range of optoelectronic materials, including organic and inorganic photovoltaic materials, nanoparticles, and conducting/semiconducting thin films.

A Time Resolved Microwave Conductivity technique for investigating direct and trap-mediated recombination dynamics and determining carrier mobilities of thin film semiconductors is presented here.

通过时间分辨微波电导率重组动力学薄膜光伏材料

A method for investigating recombination dynamics of photo-induced charge carriers in thin film semiconductors, specifically in photovoltaic materials ...

Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of electrospun titanium dioxide nanofibers (TiO2-NFs) on top of a blocking layer made of commercially available titanium dioxide nanoparticles (TiO2-NPs). This is achieved by first electrospinning a solution of titanium (IV) butoxide, polyvinylpyrrolidone (PVP), and glacial acetic acid in ethanol to obtain composite PVP/TiO2 nanofibers. These are then calcined at 500 &#176;C to remove the PVP and to obtain pure anatase-phase titania nanofibers. This material is characterized using scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The photoanode is prepared by first creating a blocking layer through the deposition of a TiO2-NPs/terpineol slurry on a fluorine-doped tin oxide (FTO) glass slide using doctor blading techniques. A subsequent thermal treatment is performed at 500 &#176;C. Then, the light-scattering layer is formed by depositing a TiO2-NFs/terpineol slurry on the same slide, using the same technique, and calcinating again at 500 &#176;C. The performance of the photoanode is tested by fabricating a dye-sensitized solar cell and measuring its efficiency through J-V curves under a range of incident light densities, from 0.25-1 Sun.

The overall goal of this project was to use electrospinning to fabricate a photoanode with improved performance for dye-sensitized solar cells.

染料敏化太阳能电池的光催化电极的电纺丝

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of ...

Dielectric RheoSANS &#8212; Simultaneous Interrogation of Impedance, Rheology and Small Angle Neutron Scattering of Complex Fluids

A procedure for the operation of a new dielectric RheoSANS instrument capable of simultaneous interrogation of the electrical, mechanical and microstructural properties of complex fluids is presented. The instrument consists of a Couette geometry contained within a modified forced convection oven mounted on a commercial rheometer. This instrument is available for use on the small angle neutron scattering (SANS) beamlines at the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR). The Couette geometry is machined to be transparent to neutrons and provides for measurement of the electrical properties and microstructural properties of a sample confined between titanium cylinders while the sample undergoes arbitrary deformation. Synchronization of these measurements is enabled through the use of a customizable program that monitors and controls the execution of predetermined experimental protocols. Described here is a protocol to perform a flow sweep experiment where the shear rate is logarithmically stepped from a maximum value to a minimum value holding at each step for a specified period of time while frequency dependent dielectric measurements are made. Representative results are shown from a sample consisting of a gel composed of carbon black aggregates dispersed in propylene carbonate. As the gel undergoes steady shear, the carbon black network is mechanically deformed, which causes an initial decrease in conductivity associated with the breaking of bonds comprising the carbon black network. However, at higher shear rates, the conductivity recovers associated with the onset of shear thickening. Overall, these results demonstrate the utility of the simultaneous measurement of the rheo-electro-microstructural properties of these suspensions using the dielectric RheoSANS geometry.

Dielectric RheoSANS &amp;#8212; Simultaneous Interrogation of Impedance, Rheology and Small Angle Neutron Scattering of Complex Fluids

Here, we present a procedure for the measurement of simultaneous impedance, rheology and neutron scattering from soft matter materials under shear flow.

介电RheoSANS  - 阻抗，流变性和复杂流体的小角中子散射的同时拷问

A procedure for the operation of a new dielectric RheoSANS instrument capable of simultaneous interrogation of the electrical, mechanical and ...

Simultaneous Multi-surface Anodizations and Stair-like Reverse Biases Detachment of Anodic Aluminum Oxides in Sulfuric and Oxalic Acid Electrolyte

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental sciences and industrial applications owing to their periodic arrangement of nanopores with relatively high aspect ratio. However, the techniques reported so far, which could be only valid for mono-surface anodization, show critical disadvantages, i.e., time-consuming as well as complicated procedures, requiring toxic chemicals, and wasting valuable natural resources. In this paper, we demonstrate a facile, efficient, and environmentally clean method to fabricate nanoporous AAOs in sulfuric and oxalic acid electrolytes, which can overcome the limitations that result from conventional AAO fabricating methods. First, plural AAOs are produced at one time through simultaneous multi-surfaces anodization (SMSA), indicating mass-producibility of the AAOs with comparable qualities. Second, those AAOs can be separated from the aluminum (Al) substrate by applying stair-like reverse biases (SRBs) in the same electrolyte used for the SMSAs, implying simplicity and green technological characteristics. Finally, a unit sequence consisting of the SMSAs sequentially combined with SRBs-based detachment can be applied repeatedly to the same Al substrate, which reinforces the advantages of this strategy and also guarantees the efficient usage of natural resources.

A protocol for fabricating nanoporous anodic aluminum oxides via simultaneous multi-surfaces anodization followed by stair-like reverse biases detachments is presented. It can be applied repeatedly to the same aluminum substrate, exhibiting a facile, high-yield, and environmentally clean strategy.

阳极氧化铝在硫酸和草酸电解质中的同时多表面 Anodizations 和阶梯式反向偏置剥离

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental ...

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser

The goal of this protocol is to present how to perform spin- and angle-resolved photoemission spectroscopy combined with polarization-variable 7-eV laser (laser-SARPES), and demonstrate a power of this technique for studying solid state physics. Laser-SARPES achieves two great capabilities. Firstly, by examining orbital selection rule of linearly polarized lasers, orbital selective excitation can be carried out in SAPRES experiment. Secondly, the technique can show full information of a variation of the spin quantum axis as a function of the light polarization. To demonstrate the power of the collaboration of these capabilities in laser-SARPES, we apply this technique for the investigations of spin-orbit coupled surface states of Bi2Se3. This technique affords to decompose spin and orbital components from the spin-orbit coupled wavefunctions. Moreover, as a representative advantage of using the direct spin detection collaborated with the polarization-variable laser, the technique unambiguously visualizes the light polarization dependence of the spin quantum axis in three-dimension. Laser-SARPES dramatically increases a capability of photoemission technique.

Here, we combine polarization-variable 7-eV laser with spin- and angle-resolved photoemission technique to visualize the spin-orbital coupling effect in solid states.

自旋角分辨光电子光谱与偏振变激光相结合的实验方法

The goal of this protocol is to present how to perform spin- and angle-resolved photoemission spectroscopy combined with polarization-variable 7-eV laser ...