这项工作部分在澳大利亚国家制造设施维多利亚节点RMIT大学的微纳米研究设施进行。作者承认这些设施以及RMIT大学显微镜、微分析设施的科技援助，该设施是澳大利亚显微镜的一个联合实验室。澳大利亚政府澳大利亚研究生奖（APA）/研究培训计划（RTP）计划的奖学金支持得到认可。我们感谢马杜·巴斯卡兰教授、苏米特·瓦利亚副教授、马修·菲尔德博士和布伦顿·库克先生的指导和有益的讨论。

1. 制造工艺和电气特征
<ol><li>使用标准图像反转光刻9 来用以下参数对设备的光电逆器进行底部电极（BE 层 1）的图案:<ol>
<li>旋转涂层的光电图在3000 rpm，软烤它在90°C为60s，暴露与25 mJ/cm2 与405 nm激光，在120°C烘烤120s，执行洪水暴露与21mW/cm2 和400nm激光，开发使用开发人员，并用去离子水冲洗。</li>
	</ol>
</li>
	<li>将 5 纳米钛 （Ti） 用于粘附，将 15 nm 铂金 （Pt） 放在顶部，并配有电子束蒸发器系统，基板图案为第 1 层。</li>
	<li>将基材放入丙酮浴中约 20 分钟，从而解除沉积金属。然后，应用超声波振动2分钟，用丙酮和异丙醇（IPA）冲洗，以完成 BE 模式。如果升空不干净，重复重复（图 1A，步骤 1）。</li>
	<li>将功能氧化物层（第 2 层）与 BE 顶部的光刻成形图案进行图案，如第 1.1 步所述。</li>
	<li>使用溅射系统 10 将 100 nm 的-VOx 和 5 nm 的 Ti 存入第2层之上。</li>
	<li>将基板放入丙酮浴中，用2-3的脉冲手动应用脉冲超声波振动，以最终确定功能氧化物模式，从而提升功能氧化物。如果图案不干净，请重复操作。（图1A、第2步和第3步）</li>
	<li>同样，使用图像反转光刻、电子束蒸发和第 1 步描述的升空过程，以 Ti_20 纳米/Pt_200纳米完成顶部电极 （TE） （第 3 层） 模式。（图 1A， 步骤 4） 注:这完成了交叉点设备图 1B的制造。</li>
	<li>对制造的设备进行电气和温度分析，以了解其电阻切换性能。<ol>
<li>使用带双探头直流 （DC） I-V 测量系统的源计和探头站进行电气测量。</li>
		<li>始终保持相关的当前合规性，以避免损坏设备。</li>
		<li>要分析设备的当前行为，请执行电压控制分析，并应用电压扫描，从正偏置的 0.1 V 的低电压开始，缓慢增加，直到观察到电成形。 注:电成形是一次性事件，在特定电压下，在最初绝缘功能氧化物中形成几纳米宽的导电细丝，这取决于固有材料特性和设备尺寸。此时，由于形成导电路径，电流图上观察到电阻突然下降或电流增加。</li>
		<li>电成形后，应用双向电压扫描以实现挥发阈值切换性能。调整电压以实现高开/关比。在这种情况下，交换比达到~10。</li>
		<li>分析室温到 90 °C 的不同温度下的电流电压特性，在 10 °C 步骤中增加，然后使用温度控制阶段倒回室温。</li>
	</ol>
</li>
</ol>2. 网格条和偏置芯片安装
<ol><li>在 CAD 软件中设计 FIB 优化网格条，并在内部使用标准加工技术进行制造，以安装用于现场 TEM 实验的偏置/加热芯片，如 图 2所示。 注: 图2A 显示网格条的单独部分，在方形战壕中同时安装三个芯片。 图 2B 显示了用于适应 TEM 的现场偏置/加热芯片的放大方形沟槽部分。</li>
	<li>将偏置芯片放入装满丙酮的玻璃培养皿中，轻轻旋转2分钟，清洁偏置芯片。然后取出芯片，放在装满甲醇的培养皿中，轻轻旋转2分钟。最后，用低压氮吹干。 注:商业上购买的偏置芯片，称为电子芯片，具有光抗光涂层保护。</li>
	<li>对齐网格条方形沟中的预清洁偏置芯片，如 图 2C所见。</li>
	<li>用螺丝固定偏置芯片顶部的网格盖，以最终确定电子芯片在网格杆上的位置（图 2D）。</li>
</ol>3. Lamella 准备，使用聚焦离子束安装偏置芯片，并就地传输电子显微镜
<ol><li>如 图 3A中所示，用厚度为 Ti_10 nm/Pt_100 nm 的较厚 BE 分别制作第 1 节中描述的样品。</li>
	<li>使用导电碳胶带将新制备的样品安装在金属存根上，并在 FIB 腔室中装载。在样品上应用额外的胶带进行接地，以避免充电问题。</li>
	<li>以 52° 倾斜度（见 图 3B）在机舱中加载偏置芯片安装的网格条。这将垂直或平行于离子束柱，具体取决于阶段旋转。</li>
	<li>使用显微镜物理控制面板和拉梅拉制备位置的软件对焦、对焦和对齐样品表面上的电子束。</li>
	<li>检查聚焦样本位置的偏心高度和电子束和离子束的光束巧合。 注:偏心高度是样品倾斜时图像不移动的位置。</li>
	<li>单击 自动 TEM 程序 （自动 lamella 准备程序），使用显微镜控制软件在集中的样本位置运行它。自动程序遵循下面描述的顺序。 注:这将完成创建TEM拉梅拉（图4）的过程。可在桌面屏幕上实时观察 AutoTEM 程序的进度。<ol>
<li>使用硅铣削创建交叉对齐标记，并在对齐标记之间的 20 μm x 5 μm 区域内沉积 1.5 μm 厚的碳保护层。</li>
		<li>碳保护层两侧的磨沟与5 nA离子束电流，以创建拉梅拉。</li>
		<li>先用 1 nA 离子束电流稀释拉梅拉，然后用 300 pA 离子束电流将拉梅拉变薄，达到 1μm 厚度。</li>
	</ol></li>
	<li>将样品倾斜到 7°，在拉梅拉上执行 J 切口，以从基板中分离出来。</li>
	<li>将样品倾斜到 0° （即垂直于电子束柱），并使用 Pt （图 5A）将拉梅拉连接到操纵器针头上。</li>
	<li>附着在微操纵器上后，用最后的切口将拉梅拉与基板分离，并慢慢缩回微操纵器（图5B）。</li>
	<li>将光束聚焦在网格杆上偏置芯片的顶部边缘，即拉梅拉安装位置。</li>
	<li>用操纵器针（图6A）缓慢地将拉梅拉带到偏置芯片上。</li>
	<li>将偏置芯片顶部边缘 17 微米间隙中心的拉梅拉对齐。慢慢地向下移动，直到它几乎不接触芯片表面，并用Pt（图6B）焊接拉梅拉的底部边缘到芯片。</li>
	<li>用硅铣削将微操纵器从拉梅拉中分离出，并收回微操纵器。</li>
	<li>将拉梅拉的顶边缘与 Pt 痕迹连接到偏置芯片的两个电极进行连接 （图6C）。 注: 在这一点上， Te 和 Be 在左右两侧都做空了。</li>
	<li>首先使用 300 pA 稀释 lamella 的中心区域，然后使用 100 pA 离子束通过将标本正面和背面倾斜 2° 来使拉梅拉厚度小于 100 nm（图 6D），以确保平行面和均匀厚度。</li>
	<li>抛光离子束损坏层与 Ga 光束加速电压 5 kV 在 5° 的角度到表面的两面。</li>
	<li>删除设备顶部和底部电极之间的短连接，在稀薄区域进行隔离切割，通过活动区域（图 7A）创建从 BE 到 TE 的电流路径。</li>
	<li>将偏置芯片与拉梅拉安装在偏置芯片支架上，然后将偏置芯片支架加载到TEM腔室。</li>
	<li>将偏置芯片支架的电线连接到源计和控制 PC。 注意:在实验过程中，请小心地放置连接线以缓解应变并最大限度地减少任何振动。</li>
	<li>等待 TEM 腔室压力下降到 4e-5 Torr，然后对焦、散射，然后使用 TEM 控制旋钮对齐拉梅拉表面横截面上的电子束。</li>
	<li>在不同的偏置电压上应用电压扫描或恒定电压，并现场收集 TEM 显微图。 注:与衍射模式、电子衍射 X 射线光谱 （EDX） 和电子能量损失光谱 （EELS） 映射相关的数据也可以在不同的偏置电压现场收集。</li>
</ol>

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作者没有什么可透露的。

本文解释了使用传输电子显微镜进行原位偏置的方案，包括设备的制造过程、偏置芯片安装的网格杆设计、偏置芯片上的拉梅拉制备和安装，以及具有原位偏置的TEM。
解释了交叉点设备的制造方法，这种方法可以很容易地扩展到横杆结构。氧化铝的 Ti 封盖对于加入非定形氧化铝至关重要，因为它在-VOx沉积后的制造步骤中溶解在水中。设备由两种不同尺?...

电阻变化氧化物记忆由于其兼容的切换速度、更小的细胞结构以及在大容量三维（3D）横杆阵列1中设计的能力，越来越多地被用作新内存和逻辑结构的构建块。迄今为止，已报告了电阻切换设备2、3的多种切换类型。金属氧化物的常见切换行为是单极、双极、互补电阻开关和挥发阈值切换。据报道，单细胞的复杂性增加了，显示多功能电阻开关性能以及4，5，6。
这种变异性意味着需要纳米结构研究来了解不同内存行为的起源和相应的切换机制，以开发明确定义的依赖条件的切换，以达到实际效用。常见的技术，以了解切换机制是深度剖析与X射线光电子光谱（XPS）7，8，纳米级二离子质谱（纳米-SIMS）6，非破坏性光发光光谱（PL）8，不同大小和厚度的电气特征的功能氧化物的设备， 纳米缩影7，传输电子显微镜（TEM），能量分散X射线光谱（EDX），和电子能量损失光谱（EELS）在TEM室6，8的横截面拉梅拉。上述所有技术都为转换机制提供了令人满意的见解。但是，在大多数技术中，需要多个样本进行分析，包括原始、电成型、设置和重置设备，以了解完整的切换行为。这增加了实验的复杂性，而且耗时。此外，故障率很高，因为在尺寸为几微米的设备中定位亚纳米级灯丝比较棘手。因此，就地实验在纳米结构特征中对于理解操作机制非常重要，因为它们在实时实验中提供了证据。
现为金属绝缘体金属 （MIM） 堆栈的不对称电阻开关交叉点设备提供现场 TEM 电气偏置的规程。此协议的主要目标是使用聚焦离子束 （FIB） 和 TEM 和电气偏置的原位实验设置为 lamella 制备提供详细的方法。这个过程是使用基于混合相非晶氧化物（a-VOx）4的不对称交叉点设备的代表性研究来解释的。此外，还介绍了结合-VOx的交叉点设备的制造过程，该装置可以使用标准的微纳米制造工艺轻松放大到横杆。这个制造过程是重要的，因为它纳入横杆-VOx溶解在水中。
该协议的优点是，只有一个拉梅拉，纳米结构的变化可以在TEM中观察到，不像其他技术，其中至少需要三个设备或跛脚。这大大简化了流程，降低了时间、成本和工作量，同时为实时操作中的纳米结构变化提供了可靠的视觉证据。此外，它采用标准的微纳米制造工艺、显微镜技术和仪器，以创新的方式建立其新颖性并解决研究空白。
在此处描述的针对-VOx的交叉点设备的代表性研究中，原位 TEM 协议有助于了解极点和挥发阈值切换4背后的切换机制。用于观察原位偏置期间-VOx中的纳米结构变化的过程和方法可以很容易地扩展到原位温度、原位温度和偏置同时，只需更换拉梅拉安装芯片，以及任何其他材料，包括金属绝缘体金属夹层结构中的两层或两层以上功能材料。它有助于揭示潜在的操作机制，并解释电气或热特性。

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		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:265px;">Resist processing system</td>
			<td style="width:173px;">EV group</td>
			<td style="width:195px;">EVG 101</td>
			<td style="width:299px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Acetone</td>
			<td style="width:173px;">Chem-Supply</td>
			<td style="width:195px;">AA008</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Biasing Chip - E-chip</td>
			<td style="width:173px;">Protochips</td>
			<td>E-FEF01-A4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Developer</td>
			<td style="width:173px;">MMRC</td>
			<td style="width:195px;">AZ 400K</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Electron beam evaporator - PVD 75</td>
			<td style="width:173px;">Kurt J Leskar</td>
			<td style="width:195px;">PRO Line - eKLipse</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">Focused Ion beam system</td>
			<td style="width:173px;">Thermo Fisher - FEI</td>
			<td style="width:195px;">Scios DualBeamTM system</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:265px;">Hot plates</td>
			<td style="width:173px;">Brewer Science Inc.</td>
			<td style="width:195px;">1300X</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Magnetron Sputterer</td>
			<td style="width:173px;">Kurt J Leskar</td>
			<td style="width:195px;">PRO Line</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mask aligner</td>
			<td style="width:173px;">Karl Suss</td>
			<td style="width:195px;">MA6</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Maskless Aligner</td>
			<td style="width:173px;">Heildberg instruments</td>
			<td style="width:195px;">MLA150</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:22px;">Methanol</td>
			<td style="width:173px;">Fisher scientific</td>
			<td style="width:195px;">M/4056</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phototresist</td>
			<td style="width:173px;">MMRC</td>
			<td style="width:195px;">AZ 5412E</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:265px;">Pt source for e-beam evaporator</td>
			<td style="width:173px;">Unicore</td>
			<td style="width:195px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">The Fusion E-chip holder</td>
			<td style="width:173px;">Protochips</td>
			<td style="width:195px;">Fusion 350</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:265px;">Ti source for e-beam evaporator</td>
			<td style="width:173px;">Unicore</td>
			<td style="width:195px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Transmission Electron Microscope</td>
			<td style="width:173px;">JEOL</td>
			<td style="width:195px;">JEM 2100F</td>
			<td></td>
		</tr>
	</tbody>
</table>

in situ transmission electron microscopy with biasing and fabrication of asymmetric crossbars based on mixed-phased a-vox

由于低成本和高密度的益处，在数字存储记忆领域，电阻式切换横杆架构非常受欢迎。由于所用材料的内在性质，不同材料显示出电阻开关特性的变异性，由于潜在的操作机制，导致该领域的差异。这突出了使用纳米结构观测来理解机制的可靠技术的必要性。该协议解释了使用传输电子显微镜 （TEM） 进行电气偏差的原位纳米结构分析的详细过程和方法。它提供了实时内存操作中潜在的纳米结构变化的视觉和可靠证据。还包括非对称横杆结构的制造方法和电气特征，其中含有非定形氧化铝。此处解释的氧化铝薄膜协议可以轻松地扩展到金属介质金属夹层结构中的任何其他材料。根据对操作机制的理解，电阻开关横杆预计将为下一代存储器设备提供可编程逻辑和神经形态电路。此协议以可靠、及时和经济高效的方式揭示了任何类型的电阻开关材料中的切换机制，从而预测了设备的适用性。

使用此协议为a-VOx交叉点设备取得的结果在图8中解释。图8A显示了完整拉梅拉的TEM显微图。在这里，衍射模式（插入）表示氧化物薄膜的无定形性质。对于原位 TEM 测量，控制电压从 25 mV 到 8 V 在 20 mV 步骤中应用，底部电极 （BE） 为正偏置，顶部电极 （TE） 接地。图8B显示，在4 V时，氧化物层中形成了局部?...

Watch this Scientific Journal Video about In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx at JoVE.com

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

这里介绍了一个协议，用于分析纳米结构的变化，在原位偏置与传输电子显微镜 （TEM） 堆叠金属绝缘体金属结构。它在下一代可编程逻辑电路和神经微敏硬件的电阻开关横杆中具有显著应用，可揭示其基本操作机制和实际适用性。

基于混合相位a-VOx的不对称横杆的偏置和制造现场传输电子显微镜

Resistive switching crossbar architecture is highly desired in the field of digital memories due to low cost and high-density benefits. Different ...

in-situ-transmission-electron-microscopy-with-biasing-fabrication

Research

JoVE Journal

Engineering

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

4.0K 次观看.  RMIT University. 这里介绍了一个协议，用于分析纳米结构的变化，在原位偏置与传输电子显微镜 （TEM） 堆叠金属绝缘体金属结构。它在下一代可编程逻辑电路和神经微敏硬件的电阻开关横杆中具有显著应用，可揭示其基本操作机制和实际适用性。

视频: In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

Revealing Dynamic Processes of Materials in Liquids Using Liquid Cell Transmission Electron Microscopy

The recent development for in situ transmission electron microscopy, which allows imaging through liquids with high spatial resolution, has attracted significant interests across the research fields of materials science, physics, chemistry and biology. The key enabling technology is a liquid cell. We fabricate liquid cells with thin viewing windows through a sequential microfabrication process, including silicon nitride membrane deposition, photolithographic patterning, wafer etching, cell bonding, etc. A liquid cell with the dimensions of a regular TEM grid can fit in any standard TEM sample holder. About 100 nanoliters reaction solution is loaded into the reservoirs and about 30 picoliters liquid is drawn into the viewing windows by capillary force. Subsequently, the cell is sealed and loaded into a microscope for in situ imaging. Inside the TEM, the electron beam goes through the thin liquid layer sandwiched between two silicon nitride membranes. Dynamic processes of nanoparticles in liquids, such as nucleation and growth of nanocrystals, diffusion and assembly of nanoparticles, etc., have been imaged in real time with sub-nanometer resolution. We have also applied this method to other research areas, e.g., imaging proteins in water. Liquid cell TEM is poised to play a major role in revealing dynamic processes of materials in their working environments. It may also bring high impact in the study of biological processes in their native environment.

We have developed a self-contained liquid cell, which allows imaging through liquids using a transmission electron microscope. Dynamic processes of nanoparticles in liquids can be revealed in real time with sub-nanometer resolution.

在液体中使用液体池透射电子显微镜揭示材料的动态过程

The recent development for in situ transmission electron microscopy, which allows imaging through liquids with high spatial resolution, has attracted ...

科研

工程学

In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devices

The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. The aggressive scaling of feature sizes, both on devices and interconnects, leads to serious challenges to ensure the required product reliability. Standard reliability tests and post-mortem failure analysis provide only limited information about the physics of failure mechanisms and degradation kinetics. Therefore it is necessary to develop new experimental approaches and procedures to study the TDDB failure mechanisms and degradation kinetics in particular. In this paper, an in situ experimental methodology in the transmission electron microscope (TEM) is demonstrated to investigate the TDDB degradation and failure mechanisms in Cu/ULK interconnect stacks. High quality imaging and chemical analysis are used to study the kinetic process. The in situ electrical test is integrated into the TEM to provide an elevated electrical field to the dielectrics. Electron tomography is utilized to characterize the directed Cu diffusion in the insulating dielectrics. This experimental procedure opens a possibility to study the failure mechanism in interconnect stacks of microelectronic products, and it could also be extended to other structures in active devices.

In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devices

The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. This paper demonstrates the procedure of an in situ TDDB experiment in the transmission electron microscope, which opens a possibility to study the failure mechanism in microelectronic products.

在透射电子显微镜原位时间相关的介质击穿:一种可能性，了解微电子器件的失效机理

The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

散装异质结太阳能电池的印刷和制作<em&gt;原位</em&gt;形态特征

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Studying Dynamic Processes of Nano-sized Objects in Liquid using Scanning Transmission Electron Microscopy

Samples fully embedded in liquid can be studied at a nanoscale spatial resolution with Scanning Transmission Electron Microscopy (STEM) using a microfluidic chamber assembled in the specimen holder for Transmission Electron Microscopy (TEM) and STEM. The microfluidic system consists of two silicon microchips supporting thin Silicon Nitride (SiN) membrane windows. This article describes the basic steps of sample loading and data acquisition. Most important of all is to ensure that the liquid compartment is correctly assembled, thus providing a thin liquid layer and a vacuum seal. This protocol also includes a number of tests necessary to perform during sample loading in order to ensure correct assembly. Once the sample is loaded in the electron microscope, the liquid thickness needs to be measured. Incorrect assembly may result in a too-thick liquid, while a too-thin liquid may indicate the absence of liquid, such as when a bubble is formed. Finally, the protocol explains how images are taken and how dynamic processes can be studied. A sample containing AuNPs is imaged both in pure water and in saline.

This protocol describes the operation of a liquid flow specimen holder for scanning transmission electron microscopy of AuNPs in water, as used for the observation of nanoscale dynamic processes.

使用扫描透射电子显微镜研究纳米大小的物体的动态过程中的液体

Samples fully embedded in liquid can be studied at a nanoscale spatial resolution with Scanning Transmission Electron Microscopy (STEM) using a ...

A Method for Obtaining Serial Ultrathin Sections of Microorganisms in Transmission Electron Microscopy

Observing cells and cell components in three dimensions at high magnification in transmission electron microscopy requires preparing serial ultrathin sections of the specimen. Although preparing serial ultrathin sections is considered to be very difficult, it is rather easy if the proper method is used. In this paper, we show a step-by-step procedure for safely obtaining serial ultrathin sections of microorganisms. The key points of this method are: 1) to use the large part of the specimen and adjust the specimen surface and knife edge so that they are parallel to each other; 2) to cut serial sections in groups and avoid difficulty in separating sections using a pair of hair strands when retrieving a group of serial sections onto the slit grids; 3) to use a 'Section-holding loop' and avoid mixing up the order of the section groups; 4) to use a 'Water-surface-raising loop' and make sure the sections are positioned on the apex of the water and that they touch the grid first, in order to place them in the desired position on the grids; 5) to use the support film on an aluminum rack and make it easier to recover the sections on the grids and to avoid wrinkling of the support film; and 6) to use a staining tube and avoid accidentally breaking the support films with tweezers. This new method enables obtaining serial ultrathin sections without difficulty. The method makes it possible to analyze cell structures of microorganisms at high resolution in 3D, which cannot be achieved by using the automatic tape-collecting ultramicrotome method and serial block-face or focused ion beam scanning electron microscopy.

This study presents reliable and easy procedures for obtaining serial ultrathin sections of a microorganism without expensive equipment in transmission electron microscopy.

一种在透射电镜中获取微生物连续超薄切片的方法

Observing cells and cell components in three dimensions at high magnification in transmission electron microscopy requires preparing serial ultrathin ...

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of lithium-ion (Li-ion) batteries. However, a number of setbacks prevent their integration into commercial devices. The main limiting factor is due to nanoscale phenomena occurring at the electrode/electrolyte interfaces, ultimately leading to degradation of battery operation. These key problems are highly challenging to observe and characterize as these batteries contain multiple buried interfaces. One approach for direct observation of interfacial phenomena in thin film batteries is through the fabrication of electrochemically active nanobatteries by a focused ion beam (FIB). As such, a reliable technique to fabricate nanobatteries was developed and demonstrated in recent work. Herein, a detailed protocol with a step-by-step process is presented to enable the reproduction of this nanobattery fabrication process. In particular, this technique was applied to a thin film battery consisting of LiCoO2/LiPON/a-Si, and has further been previously demonstrated by in situ cycling within a transmission electron microscope.

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

A protocol for the fabrication of electrochemically active LiPON-based solid-state lithium-ion nanobatteries using a focused ion beam is presented.

基于 LiPON 的固态锂离子 Nanobatteries 的聚焦离子束制备方法在原位测试中的研究

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of ...

Fabrication of Flexible Image Sensor Based on Lateral NIPIN Phototransistors

Flexible photodetectors have been intensely studied for the use of curved image sensors, which are a crucial component in bio-inspired imaging systems, but several challenging points remain, such as a low absorption efficiency due to a thin active layer and low flexibility. We present an advanced method to fabricate a flexible phototransistor array with an improved electrical performance. The outstanding electrical performance is driven by a low dark current owing to deep impurity doping. Stretchable and flexible metal interconnectors simultaneously offer electrical and mechanical stabilities in a highly deformed state. The protocol explicitly describes the fabrication process of the phototransistor using a thin silicon membrane. By measuring I-V characteristics of the completed device in deformed states, we demonstrate that this approach improves the mechanical and electrical stabilities of the phototransistor array. We expect that this approach to a flexible phototransistor can be widely used for the applications of not only next-generation imaging systems/optoelectronics but also wearable devices such as tactile/pressure/temperature sensors and health monitors.

We present a detailed method to fabricate a deformable lateral NIPIN phototransistor array for curved image sensors. The phototransistor array with an open mesh form, which is composed of thin silicon islands and stretchable metal interconnectors, provides flexibility and stretchability. The parameter analyzer characterizes the electrical property of the fabricated phototransistor.

基于侧向 NIPIN Phototransistors 的柔性图像传感器的研制

Flexible photodetectors have been intensely studied for the use of curved image sensors, which are a crucial component in bio-inspired imaging systems, ...

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

We demonstrate the use of two nuclear-based analytical methods that can follow the modifications of microstructural arrangement of iron-based metallic glasses (MGs). Despite their amorphous nature, the identification of hyperfine interactions unveils faint structural modifications. For this purpose, we have employed two techniques that utilize nuclear resonance among nuclear levels of a stable 57Fe isotope, namely M&#246;ssbauer spectrometry and nuclear forward scattering (NFS) of synchrotron radiation. The effects of heat treatment upon (Fe2.85Co1)77Mo8Cu1B14 MG are discussed using the results of ex situ and in situ experiments, respectively. As both methods are sensitive to hyperfine interactions, information on structural arrangement as well as on magnetic microstructure is readily available. M&#246;ssbauer spectrometry performed ex situ describes how the structural arrangement and magnetic microstructure appears at room temperature after the annealing under certain conditions (temperature, time), and thus this technique inspects steady states. On the other hand, NFS data are recorded in situ during dynamically changing temperature and NFS examines transient states. The use of both techniques provides complementary information. In general, they can be applied to any suitable system in which it is important to know its steady state but also transient states.

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Here, we present a protocol to describe ex situ and in situ investigations of structural transformations in metallic glasses. We employed nuclear-based analytical methods which inspect hyperfine interactions. We demonstrate the applicability of M&#246;ssbauer spectrometry and nuclear forward scattering of synchrotron radiation during temperature-driven experiments.

结构转换的原位和原位研究方法: 金属玻璃结晶的实例

We demonstrate the use of two nuclear-based analytical methods that can follow the modifications of microstructural arrangement of iron-based metallic ...

Fabrication of Magnetic Nanostructures on Silicon Nitride Membranes for Magnetic Vortex Studies Using Transmission Microscopy Techniques

Electron and x-ray magnetic microscopies allow for high-resolution magnetic imaging down to tens of nanometers. However, the samples need to be prepared on transparent membranes which are very fragile and difficult to manipulate. We present processes for the fabrication of samples with magnetic micro- and nanostructures with spin configurations forming magnetic vortices suitable for Lorentz transmission electron microscopy and magnetic transmission x-ray microscopy studies. The samples are prepared on silicon nitride membranes and the fabrication consists of a spin coating, UV and electron-beam lithography, the chemical development of the resist, and the evaporation of the magnetic material followed by a lift-off process forming the final magnetic structures. The samples for the Lorentz transmission electron microscopy consist of magnetic nanodiscs prepared in a single lithography step. The samples for the magnetic x-ray transmission microscopy are used for time-resolved magnetization dynamic experiments, and magnetic nanodiscs are placed on a waveguide which is used for the generation of repeatable magnetic field pulses by passing an electric current through the waveguide. The waveguide is created in an extra lithography step.

A protocol for the fabrication of magnetic micro- and nanostructures with spin configurations forming magnetic vortices suitable for transmission electron microscopy (TEM) and magnetic transmission x-ray microscopy (MTXM) studies is presented.

用透射显微技术制备氮化硅薄膜磁性纳米结构的研究

Electron and x-ray magnetic microscopies allow for high-resolution magnetic imaging down to tens of nanometers. However, the samples need to be prepared ...

Single-Digit Nanometer Electron-Beam Lithography with an Aberration-Corrected Scanning Transmission Electron Microscope

We demonstrate extension of electron-beam lithography using conventional resists and pattern transfer processes to single-digit nanometer dimensions by employing an aberration-corrected scanning transmission electron microscope as the exposure tool. Here, we present results of single-digit nanometer patterning of two widely used electron-beam resists: poly (methyl methacrylate) and hydrogen silsesquioxane. The method achieves sub-5 nanometer features in poly (methyl methacrylate) and sub-10 nanometer resolution in hydrogen silsesquioxane. High-fidelity transfer of these patterns into target materials of choice can be performed using metal lift-off, plasma etch, and resist infiltration with organometallics.

We use an aberration-corrected scanning transmission electron microscope to define single-digit nanometer patterns in two widely-used electron-beam resists: poly (methyl methacrylate) and hydrogen silsesquioxane. Resist patterns can be replicated in target materials of choice with single-digit nanometer fidelity using liftoff, plasma etching, and resist infiltration by organometallics.

用畸变校正扫描透射电镜进行单数字纳米电子束光刻

We demonstrate extension of electron-beam lithography using conventional resists and pattern transfer processes to single-digit nanometer dimensions by ...