这项工作是由荷兰科学研究组织（NWO）通过VIDI赠款和荷兰科学研究组织（NWO-CW）的TOP和ECHO方案的框架的化学科学部资助。

1.原子光滑，单端接面<ol><li>清洁的SrTiO 3和DyScO 3基板<ol><li>浸入基板中填充有丙酮（纯度99.5％）的烧杯中，并将其放置在超声浴（UB）为10分钟。重复此步骤与乙醇（纯度99.8％），在不之间干燥该衬底。使用氮气枪通过从表面吹乙醇滴干的样品。以这种方式，粒子中存在的乙醇不会干燥后留在表面上。 </li><li>检查表面用光学显微镜。通过轻轻擦在基板上的透镜的组织，这是浸泡在乙醇除去任何剩余的颗粒。始终使用氮气枪干燥样品。重复步骤1.1.1和1.1.2，直到表面无颗粒。 </li></ol></li><li> DyScO 3治疗-退火<ol><li>装入清洁的衬底中的石英舟和在1000＆＃退火，在一个干净的试管烘箱176下在4小时的氧流（150毫升/小时）。 </li><li>检查表面用光学显微镜。如果污垢是可见的，则使用在步骤1.1.2清洁表面中描述的方法。 </li></ol></li><li> DyScO 3治疗-由BHF表面粗化<ol><li>浸入清洁衬底在100毫升烧杯中含有40毫升去离子（DI）水，并放置在一个UB 30分钟。使用特氟隆支架承载衬底。 </li><li>填3耐HF100毫升烧杯用40ml去离子水。填写1个100毫升烧杯用40毫升乙醇中。填写1 HF耐烧杯用40毫升12.5％缓冲氟化氢（BHF，NH 4 F:HF = 87.5:12.5，pH值为5.5）。 注:BHF是一个非常危险的酸。适当的预防措施应采取。 </li><li>与DI水转印聚四氟乙烯持有者携带基板从烧杯中含有BHF烧杯中。放入UB烧杯，持续30秒。 </li><li>聚四氟乙烯持有人转移到HF耐烧杯containi纳克DI水和浸入20秒，轻轻移动支架向上和向下。在两个烧杯盛满水重复此。留与在所述含烧杯乙醇的样品保持器。 </li><li>处理所有BHF含有液体。 </li><li>干燥使用氮气枪的衬底。检查表面用光学显微镜。如果灰尘可见，重复步骤1.1.2。 </li></ol></li><li> DyScO 3治疗-选择性刻蚀用NaOH <ol><li>填的100毫升烧杯用40ml 12 M NaOH（水溶液）。沉浸使用特氟隆夹持样品，并放置在一个UB烧杯30分钟。 </li><li>转移样品到100毫升烧杯中含有40毫升的1摩尔的NaOH（水溶液）。把它放在UB 30分钟。 </li><li>填3烧杯用DI水和一种烧杯用乙醇。冲洗通过随后浸入样品中三个烧杯用水，最后在与乙醇的烧杯中。干燥使用氮气枪的样品。 </li><li>检查表面用光学microscoPE和清洁如果需要，使用在步骤1.1.2中描述的方法。该DyScO 3个样品都单独现在终止。 </li></ol></li><li>钛酸锶治疗3 <ol><li>如在步骤1.3中所述蚀刻使用BHF的清洗衬底。需要注意的是，虽然这个步骤是用于DyScO 3只是作为表面粗糙化步骤，SrO的选择性腐蚀发生在这一步。 </li><li>退火在950℃的样品中的90分钟流过的氧气（150毫升/小时）。在钛酸锶3个样品都单独现在终止。检查表面用光学显微镜，如有必要，清洗，使用在步骤1.1.2中描述的方法。 </li></ol></li></ol> 2.任意衬底原子定义模板<ol><li> 钙的制备铌3 O 10 -纳米片<ol><li>使株HCa 2的Nb 3 O 10粉末在去离子水中的分散体与0.40克/ 100 ml的浓度，并添加氢氧化四丁基铵等摩尔量（TBAOH）。请参阅Ebina 等人的 23为固态合成KCA 2铌3 O 10粉末和质子化到2株HCa铌3 O 10。 注:TBAOH腐蚀性;戴上手套，在任何时候，小心处理。 </li><li>轻轻摇动瓶子由手工和水平将其放在摇床上，在30赫兹14天。通过缓慢翻滚瓶再分散的沉淀过程中，这些14天五到六倍。 </li><li>稀释该分散体至0.40克/升，并再次轻轻摇晃。让它静置至少24小时，在使用前，为了让大的聚集体沉淀到分散体的下部。 注:批量大小会影响该过程。这里，为100毫升和500毫升乙酸乙酯稀释批初始批次制成，无论是在聚丙烯瓶中。 </li></ol></li><li> 钙的沉积铌3 O 10纳米片 注:各种版本的设备和软件产量的各种操作设置。请参阅设置的所有选项的手册。 <ol><li>通过漂洗用DI水并用氧等离子体清洗，在高能量至少3分钟为每侧清洁威廉米悬片。存储的Wilhelmy板DI水随即。 注:如果多个沉积相继完成的，所述的Wilhelmy板并不需要用氧等离子体每次处理。 </li><li>清洁朗缪尔 - 布洛杰特槽和两个障碍通过用DI水漂洗，用乙醇刷涂，再次漂洗用DI水，并用氮气干燥。确保设置被放置在一个防振台，以防止振动，并在一个盒子里，可以沉积，以防止在流动的空气和灰尘期间被关闭。 </li><li>取50毫升从用注射器新鲜纳米片分散液的上部，慢慢把它在槽。确保槽的边缘和的障碍是免费的液滴。 注意:需要一个沉积的量取决于槽的大小。水表面必须比槽的边缘略高，以确保该屏障能够适当压缩的表面上。 </li><li>让分散休息15分钟。 </li><li>选择任意基材与水溶液兼容和适当清洗。附加基板的LB设置的持有人，并给它用氮气最后一击。 注:请记住，原子级平整的电影对原子级平整基材生长。本报告中示例数据是用硅衬底，其进行清洗用乙醇，超临界二氧化碳的射流30秒和氧等离子体的高能量为5分钟获得的。 </li><li>衬底支架安装到设置。就拿威廉米悬片，浸在低谷，小心将其连接到了春天。从板用一张纸的丝除去液滴。&lt;/ li&gt; <li>降低基板，直到它接触到纳米片分散液的表面上，设置在软件的高度为零，并降低基板进一步直至所需深度。确保衬底支架不接触纳米片分散。 </li><li>设置在软件为零的表面压力，并让该分散休息15分钟。 15分钟后的表面压力通常达到1〜2分钟/米。大的偏差可能表明以下沉积的质量较差。 </li><li>设置在软件上的表面压力来再次为零，通过移动与3.0毫米/分钟慢慢压缩表面的速度的障碍开始淀积的第一级。确保在软件目标压力的值是远高于预期，在步骤2.2.10（ 即，为20mN / m）的最大值。 </li><li>监测表面压力和表面面积的发展。等到压力的增加减慢显著和压力approache它时的最大值。确保壁垒永远达不到的Wilhelmy板。最大压力通常达到15.0〜18.0达因/厘米，但是这既不是一个绝对的，也不是一个恒定值。 </li><li>输入到达值作为目标压力，设置杓高度与实际值和通过抽出从分散基板为1.0毫米/分钟的速率开始淀积的第二阶段。监测表面压力。 </li><li>取出的Wilhelmy板当沉积完成时，冲洗用DI水，并再次将其存储在DI水中。 </li><li>除去基材后，它已经完全干燥。 </li><li>多层沉积，分解从先前层中的有机残基。这可以例如通过加热在微波炉中进行30分钟，或通过紫外线照射30分钟，进行至600℃。从步骤2.2.2重复协议，但不要清洁衬底比用氮气吹其他。 </li></ol></li></ol>

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The authors declare that they have no competing financial interests.

所有的钙钛矿氧化物衬底处理的最重要的方面是工作的清洁度。表面污染防止的衬底区域蚀刻，而在退火期间不希望的反应，可以很容易地破坏表面。 的不同步骤的顺序是重要的。在DyScO 3的治疗中，在退火步骤应在蚀刻工序之前进行的，因为后退火导致无用的Dy扩散从散装到衬底的表面上。蚀刻在12 M氢氧化钠溶液后，1M溶液应该总是以防止氢氧化镝络合物沉淀到衬底的表面使用。浸泡在水中是必要的的SrTiO 3处理，以hydroxylize所述的SrO。以这种方式，短的蚀刻时间可用于这防止破坏性表面由于不受控制的蚀刻。浸渍在水中，以防DyScO的可选步骤<sub&gt; 3的治疗。这个步骤是简单地从标准化的SrTiO 3治疗程序复制并预计不会有在处理任何意义。 退火步骤是必要的，以提高在表面的结晶度。所指示的退火时间为DyScO 3和的SrTiO 3理疗倍，平均而言，导致良好定义步骤壁架。但是，有时退火时间，需要增加对于基板具有低斜切的角， 例如，具有更广泛的阳台。然后，所需增加的扩散长度为表面原子找到最佳站点。在的SrTiO 3的情况下，一个过长的退火时间可能会造成从散装到表面锶原子的不想要的扩散。此第二终端所用的表面形态进行观察外观直台阶边缘与方孔的，如在上代表性结果的部分中描述。在这种情况下，表面处理C一个可重复的，但最后的退火步骤应在920℃进行30分钟，26来执行。 在这个协议中所描述的方法是最成功的方法（001）的SrTiO 3和稀土scandates，但只适用于这些衬底。然而，对于其他基材的方法应调整到精确的表面化学。这也需要在与其它取向基材时，或当A位，而不是B位终止是期望的。现有治疗方法的概述可以在Sanchez 等人6和Schlom 等人的发现。2 关于纳米片的晶种层，该方法的精巧部件，以获得高质量的纳米片的分散体，并防止在沉积过程中的污染。层状母体化合物转化成单层纳米片通过加入膨松有机离子的脱层发生容易，但纳米片倾向于聚集在分散性和聚集体，例如，会妨碍均匀的单层的沉积。因此，这是非常重要的，留下新鲜稀释分散体在休息至少24小时后再使用和不使用分散体的下部。这使得时间为大的聚集体沉降，分散体的上部会变得相对较纯的。由于持续的聚集将不断降低色散，用一个星期内稀释建议后。请注意，在整个分散体体积的纳米片的浓度存在梯度导致在LB沉积在表面压力值的一些变化，这取决于从库存取分散的体积局部纳米片的浓度。此外，LB沉积是基于表面活性分子，因此是对污染和运动非常敏感。设置和威廉米板仔细清洗（最好用清洁工具专门用于仅此设置）和保护股份公司ainst流动空气和振动是很重要的。 上创建任意基材由LB沉积纳米片的晶种层的概念是在薄膜生长领域中的有价值的工具。纳米片的原子完美的表面产生高品质的外延片，在原则上，任何薄膜材料相匹配的晶格参数。纳米片可以沉积在几乎任何基底材料，因而其他材料可以代替相对昂贵和大小受限的单晶衬底。 LB法使纳米片沉积在单层具有高可控性是一般不能用相同的电泳沉积或絮凝其它常规技术来实现。11然而，瓶颈是在种子层的完善程度。高的膜的品质在大面积上所需要的功能性器件，迄今可靠的应用，这还没有实现。沉积纳米片与完美的覆盖范围和优选还控制其在面内取向是在该领域的主要挑战。然而，在本领域的当前状态已被证明是在研究的一个重要工具。

大量的研究的是外延薄膜，并且可以通过调整材料的组成和结构而获得的复合氧化物，由于在大范围的功能性质的异质结构进行。由于多种生长技术的发展，现在有可能让一个大的范围的组合物和那些不能在散装达到结晶品质薄膜。1连同事实，即这些材料的特性是高度各向异性的，这使得该在外延膜的现象和功能被观察到，未在散装获得。此外，外延应变和创造异质结构可以用于获得新的或增强的性能。2 为了生长外延膜和异质结构具有所需的性质，具有良好定义的表面基片是必需的。在表面化学或形态的地方差异导致不均匀ñucleation和生长，从而产生了不希望的缺陷和晶界中的膜。此外，膜和衬底之间的界面起着决定，因为薄膜的厚度有限的性质有重要的作用。这意味着基片要求是在原子水平光滑和均匀的。 这一标准是难以达到时衬底所使用的自然不必明确定义的表面， 例如，其他的复合氧化物。从这个角度来看，钙钛矿型氧化物是研究最多的衬底材料中的一个。钙钛矿型氧化物可以由通式ABO 3，其中A和B代表金属离子来表示。几乎所有的金属所用的A或B位置，这使得能够制造大范围的不同底物的掺入。基底材料的多功能性允许一个曲调生长在它上面的膜的特性通过调整所施加的外延应变的d为结构在界面处。然而，在这些衬底上生长并不简单，由于钙钛矿表面上，这是在（001）取向衬底尤其可见的模糊性。在（001）方向，钙钛矿可以看作交替的AO和BO 2层。当（001）取向衬底通过从较大的晶体切割制成，二者的氧化物存在于表面上。这种现象示于图1，由于晶体是从来没有完全沿着（001）面切割，表面形成由梯田与单元电池的高度差的。然而，半单元电池的高度差存在为好，这表明这两种类型的表面端子的存在。具有单封端的钙钛矿基板以生长具有均匀性质的连续膜是很重要的，因为已经特别示出对于钙钛矿型氧化物膜的生长。终止可能导致在生长为k的差大inetics，导致不连续的膜的生长3 - 5此外，堆叠顺序应该是跨越完整膜衬底界面类似，由于AO-B&#39;O接口可具有完全不同的性能比BO-A&#39;O接口。 6 在第一次成功的方法，以获得一个单一的终止钙钛矿氧化物表面的SrTiO 3（001）取向衬底被开发了。川崎等人，7引入湿法蚀刻方法，该方法后来被科斯特等改善。8所述的方法包括通过羟基化该氧化物在水中增加朝向酸性蚀刻SrO的敏感性，随后是短暂的蚀刻在缓冲氟化氢（BHF）。随后的退火，以增加结晶度产生的原子级平滑表面只有二氧化钛的存在。以后，一个方法，以获得单个终止稀土scandates由开发使用稀土氧化物的更高的溶解度相比在碱性溶液scandates。这种方法特别适用于面向DyScO 3的正交（110）中所述，并且它表明，它有可能获得完全钪终止表面。9,10，以获得这些单封端的SrTiO 3和DyScO 3衬底在此所描述的方法协议。 虽然单晶钙钛矿基材的值是明确的，可替代地，可用于外延膜生长的任意衬底，而不适当的晶体结构为好。基板是不适合的外延薄膜生长本身可以通过用一层纳米片覆盖它们制成合适的模板。纳米片基本上是二维的单晶，其厚度为几纳米，并且在微米范围11的横向尺寸，从而藏有直接日的外延生长的能力在电影。通过在任意衬底上淀积一层纳米片的，则对于任何膜材料的相匹配的晶格参数取向生长创造了籽晶层。这种方法已经被报道成功为的定向生长的氧化锌为例， 二氧化钛，钛酸锶3，LaNiO 3，铅（锆，钛）O 3和SrRuO 3月 12日- 15通过使用纳米片，价格相对较高和规模的限制常规单晶衬底可避免与纳米片可以沉积在几乎任何基底材料。 纳米片通常由层状母体化合物的脱层通过交换层间的金属离子与笨重母体化合物获得成其离散的层，与由母体化合物的晶体结构来确定其具体的厚度。11脱层可在含水环境中可以实现有机离子，这将导致结构膨胀并最终进入分层单层纳米片。这导致被反电荷的有机离子包围带电纳米片的胶体分散体。剥离过程的示意图示于图2，在本协议中， 钙的Nb 3 O 10 -纳米片被用来作为一个模型系统和这些可以从钙钛矿母体化合物株HCa 2的Nb 3 O 10来获得。 钙铌3 O 10 -纳米片具有面内晶格参数几乎等于那些的SrTiO 3和显示一个原子级平滑，单封端的表面。因此，高品质的薄膜，可以生长在单个纳米片。一旦获得纳米片的水分散体，它们可以被淀积在任意衬底由朗缪尔 - 布洛杰特（LB）沉积上。此方法使纳米片沉积在单层具有高可控性即克enerally不能通过象电泳沉积或絮凝其它常规技术来实现。11围绕纳米片的有机离子表面活性分子和趋于扩散到分散体的表面上，形成浮动纳米片的单层。这种单层可以压缩成致密堆积和沉积在任意的基板。沉积过程的示意图示于图3;超过95％的表面覆盖率一般达到15 - 18，这主要发生不纳米片堆叠或重叠的边缘。多层膜可通过重复沉积而获得。 在本协议的Ca 2铌3 O 10 -纳米片被用作模型系统，但使用纳米片作为种子层为外延膜生长的原理是比较广泛适用的。虽然氧化物纳米片得到更多的注意作为种子层在文献中，该概念可以扩展到非氧化物纳米片如BN，砷化镓，的TiS 2，ZnS和的MgB 2为好。此外，由于纳米片继承其母体化合物的组合物中，各种功能可以由母体结构的适当的设计插入。除了 ​​其作为籽晶层进行取向薄膜生长的使用，各种纳米片已被证明是在研究基本材料的性能和设计新的功能结构的宝贵工具箱11,19 - 22 这个协议显示了实验程序，以获取不同类型的模板，用于外延生长的氧化物的薄膜。完整的程序，以获取良好定义的单封端的SrTiO 3和DyScO 3基板被描述，以及该过程来制造的Ca 2铌3 O 10 -上arbitrar纳米片层Ÿ基板。

<table><tbody><tr><td>tetra-n-butyl ammonium hydroxide (40 wt% aq)</td><td>Alfa Aesar</td><td>L02809</td><td>corrosive</td></tr><tr><td>Langmuir Blodgett setup (include trough, barriers, Wilhelmy plate, frame etc.)</td><td>KSV NIMA</td><td>see catalogue behind link for multiple options</td><td>http://www.ksvnima.com/file/brochures-2/ksvnimallbaccessoryandmodules&lt;br/&gt; 23-8-2013.pdf</td></tr><tr><td>Buffered hydrogen fluoride (NH&lt;sub&gt;4&lt;/sub&gt;F:HF = 87.5:12.5)</td><td>Sigma Aldrich</td><td>40207</td><td>Hazard statements: H301-H310-H314-H330, precautionary statements: P260-P280-P284-P301 + P310-P302 + P350-P305 + P351 + P338</td></tr><tr><td>NaOH (reagent grade)</td><td>Sigma Aldrich</td><td>S5881&amp;nbsp;</td><td>Hazard statements: H290-H314, precautionary statements:&amp;nbsp; P280-P305 + P351 + P338-P310 , product purchased as pellets, the 12 and 1 M solutions should be made from these pellets.</td></tr><tr><td>Tube furnace (Barnstead 21100)</td><td>Sigma Aldrich</td><td>Z229725</td><td></td></tr><tr><td>STO and DSO substrates</td><td>CrysTec GmbH, Germany</td><td></td><td>www.crystec.de, size used 5 x 5 x 0.5 mm&lt;sup&gt;3&lt;/sup&gt;</td></tr></tbody></table>

atomically defined templates for epitaxial growth of complex oxide thin films

原子限定衬底表面是先决条件的复合氧化物薄膜的外延生长。在这个协议中，有两种方法来获得这样的表面进行了描述。第一种方法是单封端的钙钛矿的SrTiO 3（001）和DyScO 3（110）衬底的制备方法。湿蚀刻来选择性地去除所述两个可能表面端子之一，而退火步骤来增加表面的光滑度。将所得的单封端的表面允许为钙钛矿氧化物薄膜的高结晶质量和衬底和膜之间良好定义的接口的异质外延生长。在第二种方法中，由朗缪尔 - 布洛杰特（LB）纳米片的沉积创建种子层为外延膜生长的任意衬底。作为模型系统的Ca 2铌3 O 10 -纳米片被使用，准备他们的分层母体化合物的分层2株HCa铌3 O 10。与纳米片创建种子层的一个主要优点是相对昂贵和大小受限的单晶基材可以通过几乎任何基底材料来代替。

步骤1）的SrTiO 3和DyScO 3基板的选择性蚀刻 原子力显微镜（AFM）是一种简单的方法来获得的指示对治疗的成功。其中仅被闪蒸至650℃（ 图4A）的的SrTiO 3基片的AFM图像示出了粗糙的表面，这表明在高温退火步骤的必要性。退火基板（ 图4A-C）的原子力显微镜的数据清楚地显示了两个表面终止，由于在摩擦图像鲜明对比观察，以及在该高度图象的横截面半单元电池的高度差。 图5示出了原子力显微镜的TiO 2的图像终止的SrTiO 3基片，其是根据在此协议中描述的方法处理。大规模的，直露台凸缘可以观察到（ 图5A）。对规模较小，非常光滑的阶地观察到的，和台面之间唯一单元电池的高度差被测量，如预期的单封端的表面。上具有较大的阶地， 即，用更小的斜切角度基板，单元电池深孔是靠近阳台凸缘（ 图5B）中可见。这些孔消失当使用较长的退火时间，从而导致形态类似于具有更高斜切角（ 图5C）的单封端的底物。这些孔的形态，以及在露台凸缘的形态，是单终止的一个重要标志。24在单个终止衬底，所述孔是圆形的形状，而在露台凸缘是圆形的。相比之下，锋利的露台壁架和方孔上双终止基板（ 见图4B）可见。 单端接的另一个标志出现在反射高能电子DIFFRACT离子（RHEED）的图像， 如图6，在作为接收到的底物，出现条纹的RHEED图像，由于表面的结晶度较差。退火在氧或充分的基质的处理后，将表面被更有序，这可以通过菊池线和尖锐的衍射点的外观可以看出。但是，在单端的衬底的情况下，相对于基板被仅退火的衍射斑点是更小。更重要的是，除了在（1×1）的斑点，没有额外的斑点是可见的，它总是存在的双封端的基片的图案在DyScO 3的情况下，更难以看到的处理是否成功。没有差异可以退火双封端的基板的RHEED图案和化学处理过的SCO 2终止衬底0.10。在图7中 ，不同退火DyScO 3基板的AFM图像之间可以看到s的显示。不同终端可以很容易地看出，在图7A-D。图7E和 F显示预期用于单端的基板上的形态， 即只4埃步骤是可见的。然而，该混合终止仍然可以发生在非常小的规模。由于AFM的有限的分辨率，不同终端的区域不清晰可见。相比单封端的表面高度和相位图像中较高的表面粗糙度均为终端的存在的指示。 扫描探针显微术和表面衍射技术是不足以完全确定治疗的成功。第二终止次要区域可以不与这两种类型的技术，由于有限的分辨率观察到。然而，这些小的区域可具有对膜的质量有显着的影响， 如图8。SrRuO所述的核<suB&gt; 3是对表面终止状态非常敏感。虽然3-5的DyScO 3和钛酸锶3基板分别在AFM图像图8C和 F似乎表明单端接面，SrRuO 3的增长表明，其他终端的地区依次为仍然存在。在结束时，治疗的成功只能完全确定考虑到生长膜的质量。 步骤2） 钙的沉积铌3 O 10 -对任意纳米片基板 期间纳米片沉积在表面压力的变化可以被监视，这给出了一个指示在沉积如何前进。初始表面积压缩和纳米片的实际沉积期间的表面压力的典型曲线显示于图9的压力通常会增加一个增量easingly密实更迅速地填充密度漂浮纳米片和增加的接近100％。实际沉积应该开始之前的表面压力达到其最大值而这种压力将被保持在整个沉积。在的情况下的压力传递其最大和（略）崩溃，这可能表示，该高压缩力所引起的一些纳米片的边缘彼此重叠，并创建（部分）栈。只要压力不接近最大时，纳米片尚未组织成一个密集的包装。在实际的沉积，障壁慢慢来回移动，以使纳米片单层本地重组，这将导致一个锯状压力轮廓。 纳米片的单层的典型的AFM图像示于图10中的纳米片表面是平滑的，并与邻近的空白的高度差接近1.44纳米晶体厚度钙2铌3 O 10 -层在其母体化合物11。纳米片的单层完全（001）取向的离开平面的方向，但具有随机的面内取向，由于随机面内排序的纳米片。为了说明它们的晶体取向和质量， 图11示出了外延SrRuO 3的电子背散射衍射（EBSD）图像上生长的Ca 2铌3 O 10 -纳米片具有的SrTiO 3的中间层。该薄膜具有在所有纳米片的外的面（001）取向，并且具有单一的面内取向个别纳米片。这种薄膜的表面形态示出与图 AFM图像12 .The台阶高度在连续部分或者与纳米片的厚度或具有SrRuO 3的单元电池的高度相对应，在原子级完美nanoshe确认高质量薄膜生长ETS。对外延SrRuO 3薄膜生长用这样的方法的属性的扩展报告请参阅Nijland 等人的 15 <img alt="图1" src="/files/ftp_upload/52209/52209fig1highres.jpg" /> 立方钙钛矿晶胞图1（A）的示意图。中，金属离子A和B分别位于，角部和单元电池的中心。氧原子位于立方体的面，形成围绕乙离子八面体。（B）的（001）的示意图取向的钙钛矿基板。由于斜切，表面是由梯田。两个端子，AO和BO 2，存在于表面上。（C）的一个完全BO 2终止衬底的示意图。（D）的原子力显微镜一个DyScO 3基板的表面的图像退火在1000之后<html> 6;下进行4小时。在露台的粗糙度是由两个表面端接的存在而产生的，如图所示的线剖面（E），其中，不仅是4的单元电池的步骤，但也为2的高度的差异是明显的。 附图的AC适于从Kleibeuker 等 9 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/52209/52209fig2highres.jpg" /> 图2.层状母体化合物转化成单层纳米片。具有膨松分子离子交换的分层的示意图导致膨胀的结构，并降低了层间的静电力，使各层被彼此分离。获得="_空白"&gt;点击此处查看该图的放大版本。 <img alt="图3" src="/files/ftp_upload/52209/52209fig3highres.jpg" /> 通过LB法沉积纳米片的图3的示意图。该纳米片浮动朝向分散体的表面和被压缩成一个密实填充通过移动向内的障碍。衬底然后慢慢地从分散撤回。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图4" src="/files/ftp_upload/52209/52209fig4highres.jpg" /> 图4。已被闪蒸至650℃的的SrTiO 3基片（A）的 AFM图像。（B）中的AFM高度和（C）的摩擦图像中的双封端的SrTiO 3基片，显示出尖锐的台阶边缘和台面与半单元电池的高度差相对于相邻的梯田，在（D）中所示的AFM高度图像的线剖面为可见。在两个不同的终端引起摩擦图像清晰的对比。图从科斯特等人采取了许可。8 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig4large.jpg" target="_blank">，请点击这里查看此图的放大版本。</a> <img alt="图5" src="/files/ftp_upload/52209/52209fig5highres.jpg" /> 图5.（AC）的单封端的SrTiO 3基片的AFM图像。（D）是（C）的一个轮廓线，仅示出单元电池的高度差。在（B）中的圆圈表示单元电池深HOL之一<html> ES这是近低斜切角度基板的阳台窗台可见。图从科斯特等 24采取许可<a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig5large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图6" src="/files/ftp_upload/52209/52209fig6highres.jpg" /> 图（A）的一个6 RHEED图像作为接收的SrTiO 3基片，（B）一种退火衬底和（C）一种单封端的SrTiO 3基片。图从科斯特等 24采取许可<a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig6large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 载/ 52209 / 52209fig7highres.jpg"/&gt; 图7。 退火DyScO 3基板AFM影像。（AD）清楚地表明端接两次面。然而，该形态可从基底变化到基板。 （E）和（F）的表面上看起来更均匀，并且只有电池单元的高度差可以被测量。然而，在AFM的分辨率可太低测量第二终端25的一小块区域。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig7large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图8" src="/files/ftp_upload/52209/52209fig8highres.jpg" /> SrRuO图8. AFM图像3片上生长的SrTiO 3和DyScO 3基板。在（A）的电影和<stro<html>纳克&gt;（D）的生长在其上是根据在此协议中描述的方法处理过的分别的SrTiO 3和DyScO 3衬底。该膜是非常平滑，并在（B）和（E）中所示的相应的线剖面，只显示单元电池的高度差。在（C）和（F）的所述薄膜上生长双封端的退火衬底。沟槽是可见的，因为他们位于膜厚度的范围内。在（D）和（F）中的插图显示生长前的衬底。需要注意的是两个表面都是非常光滑。图从Kleibeuker 等人采取了许可。9 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig8large.jpg" target="_blank">，请点击这里查看此图的放大版本。</a> <html> hres.jpg"/&gt; 图面压力9.典型地块最初的表面积在压缩过程中和Ca 2 Nb的实际沉积3 O 10 -纳米片 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig9large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图10" src="/files/ftp_upload/52209/52209fig10highres.jpg" /> 图10。 典型的AFM图像和Ca 2铌单层线轮廓3 O 10 -纳米片沉积在硅衬底上的纳米片显示光滑的表面。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig10large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> "SRC ="/文件/ ftp_upload / 52209 / 52209fig11highres.jpg"/&gt; 。外延SrRuO 3上生长的Ca 2铌3 O 10的图11的EBSD图像-纳米片具有的SrTiO 3构成的中间层的膜具有在所有纳米片的外的面（001）取向，并且具有单一的平面内取向对个人纳米片。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig11large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图12" src="/files/ftp_upload/52209/52209fig12highres.jpg" /> 图12。 AFM图像和线外延SrRuO 3上生长的Ca 2铌3 O 10的轮廓。 -纳米片具有的SrTiO 3的中间层的步骤在连续的部件的高度相匹配的纳米片厚度1.4纳米和0.4纳米SrRuO 3单元格高度。 <a href="https://jove.unicartagenaproxy.elogim.com/files/ftp_upload/52209/52209fig12large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

Watch this Scientific Journal Video about Atomically Defined Templates for Epitaxial Growth of Complex Oxide Thin Films at JoVE.com

Atomically Defined Templates for Epitaxial Growth of Complex Oxide Thin Films

各种程序概述来制备原子定义的模板为复合氧化物薄膜的外延生长。单晶的SrTiO 3（001）和DyScO 3的化学处理（110）衬底上进行，以获得原子级平滑，单封端的表面。 钙的Nb 3 O 10 -纳米片被用来创建任意原子基定义的模板。

原子定义模板复合氧化物薄膜的外延生长

Atomically defined substrate surfaces are prerequisite for the epitaxial growth of complex oxide thin films. In this protocol, two approaches to obtain ...

atomically-defined-templates-for-epitaxial-growth-complex-oxide-thin

Universidad de Cartagena UDEC

Research

JoVE Journal

Chemistry

14.2K 次观看.  University of Twente. 各种程序概述来制备原子定义的模板为复合氧化物薄膜的外延生长。单晶的SrTiO 3（001）和DyScO 3的化学处理（110）衬底上进行，以获得原子级平滑，单封端的表面。 钙的Nb 3 O 10 -纳米片被用来创建任意原子基定义的模板。 

视频: Atomically Defined Templates for Epitaxial Growth of Complex Oxide Thin Films

Towards Biomimicking Wood: Fabricated Free-standing Films of Nanocellulose, Lignin, and a Synthetic Polycation

Woody materials are comprised of plant cell walls that contain a layered secondary cell wall composed of structural polymers of polysaccharides and lignin. Layer-by-layer (LbL) assembly process which relies on the assembly of oppositely charged molecules from aqueous solutions was used to build a freestanding composite film of isolated wood polymers of lignin and oxidized nanofibril cellulose (NFC). To facilitate the assembly of these negatively charged polymers, a positively charged polyelectrolyte, poly(diallyldimethylammomium chloride) (PDDA), was used as a linking layer to create this simplified model cell wall. The layered adsorption process was studied quantitatively using quartz crystal microbalance with dissipation monitoring (QCM-D) and ellipsometry. The results showed that layer mass/thickness per adsorbed layer increased as a function of total number of layers. The surface coverage of the adsorbed layers was studied with atomic force microscopy (AFM). Complete coverage of the surface with lignin in all the deposition cycles was found for the system, however, surface coverage by NFC increased with the number of layers. The adsorption process was carried out for 250 cycles (500 bilayers) on a cellulose acetate (CA) substrate. Transparent free-standing LBL assembled nanocomposite films were obtained when the CA substrate was later dissolved in acetone. Scanning electron microscopy (SEM) of the fractured cross-sections showed a lamellar structure, and the thickness per adsorption cycle (PDDA-Lignin-PDDA-NC) was estimated to be 17 nm for two different lignin types used in the study. The data indicates a film with highly controlled architecture where nanocellulose and lignin are spatially deposited on the nanoscale (a polymer-polymer nanocomposites), similar to what is observed in the native cell wall.

The objective of this research was to form synthetic plant cell wall tissue using layer-by-layer assembly of nanocellulose fibrils and isolated lignin assembled from dilute aqueous suspensions.&#160; Surface measurement techniques of quartz crystal microbalance and atomic force microscopy were used to monitor the formation of the polymer-polymer nanocomposite material.

朝仿生学木:纳米纤维素，木质素的装配式自由站立电影和合成聚阳离子

Woody materials are comprised of plant cell walls that contain a layered secondary cell wall composed of structural polymers of polysaccharides and ...

科研

化学

Fabrication of Spatially Confined Complex Oxides

Complex materials such as high Tc superconductors, multiferroics, and colossal magnetoresistors have electronic and magnetic properties that arise from the inherent strong electron correlations that reside within them. These materials can also possess electronic phase separation in which regions of vastly different resistive and magnetic behavior can coexist within a single crystal alloy material. By reducing the scale of these materials to length scales at and below the inherent size of the electronic domains, novel behaviors can be exposed. Because of this and the fact that spin-charge-lattice-orbital order parameters each involve correlation lengths, spatially reducing these materials for transport measurements is a critical step in understanding the fundamental physics that drives complex behaviors. These materials also offer great potential to become the next generation of electronic devices 1-3. Thus, the fabrication of low dimensional nano- or micro-structures is extremely important to achieve new functionality. This involves multiple controllable processes from high quality thin film growth to accurate electronic property characterization. Here, we present fabrication protocols of high quality microstructures for complex oxide manganite devices. Detailed descriptions and required equipment of thin film growth, photo-lithography, and wire-bonding are presented.

We describe the use of pulsed laser deposition (PLD), photolithography and wire-bonding techniques to create micrometer scale complex oxides devices. The PLD is utilized to grow epitaxial thin films. Photolithography and wire-bonding techniques are introduced to create practical devices for measurement purposes.

空间密闭的复合氧化物制备

Complex materials such as high Tc superconductors, multiferroics, and colossal magnetoresistors have electronic and magnetic properties that arise from ...

工程学

Writing and Low-Temperature Characterization of Oxide Nanostructures

Oxide nanoelectronics is a rapidly growing field which seeks to develop novel materials with multifunctional behavior at nanoscale dimensions. Oxide interfaces exhibit a wide range of properties that can be controlled include conduction, piezoelectric behavior, ferromagnetism, superconductivity and nonlinear optical properties. Recently, methods for controlling these properties at extreme nanoscale dimensions have been discovered and developed. Here are described explicit step-by-step procedures for creating LaAlO3/SrTiO3 nanostructures using a reversible conductive atomic force microscopy technique. The processing steps for creating electrical contacts to the LaAlO3/SrTiO3 interface are first described. Conductive nanostructures are created by applying voltages to a conductive atomic force microscope tip and locally switching the LaAlO3/SrTiO3 interface to a conductive state. A versatile nanolithography toolkit has been developed expressly for the purpose of controlling the atomic force microscope (AFM) tip path and voltage. Then, these nanostructures are placed in a cryostat and transport measurements are performed. The procedures described here should be useful to others wishing to conduct research in oxide nanoelectronics.

Oxide nanostructures provide new opportunities for science and technology. The interfacial conductivity between LaAlO3 and SrTiO3 can be controlled with near-atomic precision using a conductive atomic force microscopy technique. The protocol for creating and measuring conductive nanostructures at LaAlO3/SrTiO3 interfaces is demonstrated.

写作和氧化物纳米结构的低温特性

Oxide nanoelectronics is a rapidly growing field which seeks to develop novel materials with multifunctional behavior at nanoscale dimensions.  Oxide ...

Atomically Traceable Nanostructure Fabrication

Reducing the scale of etched nanostructures below the 10 nm range eventually will require an atomic scale understanding of the entire fabrication process being used in order to maintain exquisite control over both feature size and feature density. Here, we demonstrate a method for tracking atomically resolved and controlled structures from initial template definition through final nanostructure metrology, opening up a pathway for top-down atomic control over nanofabrication. Hydrogen depassivation lithography is the first step of the nanoscale fabrication process followed by selective atomic layer deposition of up to 2.8 nm of titania to make a nanoscale etch mask. Contrast with the background is shown, indicating different mechanisms for growth on the desired patterns and on the H passivated background. The patterns are then transferred into the bulk using reactive ion etching to form 20 nm tall nanostructures with linewidths down to ~6 nm. To illustrate the limitations of this process, arrays of holes and lines are fabricated. The various nanofabrication process steps are performed at disparate locations, so process integration is discussed. Related issues are discussed including using fiducial marks for finding nanostructures on a macroscopic sample and protecting the chemically reactive patterned Si(100)-H surface against degradation due to atmospheric exposure.

We report a protocol for combining the atomic metrology of the Scanning Tunneling Microscope for surface patterning with selective Atomic Layer Deposition and Reactive Ion Etching. Using a robust process involving numerous atmospheric exposures and transport, 3D nanostructures with atomic metrology are fabricated.

原子纳米结构可追溯制造

Reducing the scale of etched nanostructures below the 10 nm range eventually will require an atomic scale understanding of the entire fabrication process ...

Epitaxial Growth of Perovskite Strontium Titanate on Germanium via Atomic Layer Deposition

Atomic layer deposition (ALD) is a commercially utilized deposition method for electronic materials. ALD growth of thin films offers thickness control and conformality by taking advantage of self-limiting reactions between vapor-phase precursors and the growing film. Perovskite oxides present potential for next-generation electronic materials, but to-date have mostly been deposited by physical methods. This work outlines a method for depositing SrTiO3 (STO) on germanium using ALD. Germanium has higher carrier mobilities than silicon and therefore offers an alternative semiconductor material with faster device operation. This method takes advantage of the instability of germanium's native oxide by using thermal deoxidation to clean and reconstruct the Ge (001) surface to the 2&#215;1 structure. 2-nm thick, amorphous STO is then deposited by ALD. The STO film is annealed under ultra-high vacuum and crystallizes on the reconstructed Ge surface. Reflection high-energy electron diffraction (RHEED) is used during this annealing step to monitor the STO crystallization. The thin, crystalline layer of STO acts as a template for subsequent growth of STO that is crystalline as-grown, as confirmed by RHEED. In situ X-ray photoelectron spectroscopy is used to verify film stoichiometry before and after the annealing step, as well as after subsequent STO growth. This procedure provides framework for additional perovskite oxides to be deposited on semiconductors via chemical methods in addition to the integration of more sophisticated heterostructures already achievable by physical methods.

This work details the procedures for the growth and characterization of crystalline SrTiO3 directly on germanium substrates by atomic layer deposition. The procedure illustrates the ability of an all-chemical growth method to integrate oxides monolithically onto semiconductors for metal-oxide semiconductor devices.

锗通过原子层沉积钙钛矿型钛酸锶的外延生长

Atomic layer deposition (ALD) is a commercially utilized deposition method for electronic materials. ALD growth of thin films offers thickness control and ...

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures

The quasi 2D electron system (q2DES) that forms at the interface between LaAlO3 (LAO) and SrTiO3 (STO) has attracted much attention from the oxide electronics community. One of its hallmark features is the existence of a critical LAO thickness of 4 unit-cells (uc) for interfacial conductivity to emerge. Although electrostatic mechanisms have been proposed in the past to describe the existence of this critical thickness, the importance of chemical defects has been recently accentuated. Here, we describe the growth of metal/LAO/STO heterostructures in an ultra-high vacuum (UHV) cluster system combining pulsed laser deposition (to grow the LAO), magnetron sputtering (to grow the metal) and X-ray photoelectron spectroscopy (XPS). We study step by step the formation and evolution of the q2DES and the chemical interactions that occur between the metal and the LAO/STO. Additionally, magnetotransport experiments elucidate on the transport and electronic properties of the q2DES. This systematic work not only demonstrates a way to study the electrostatic and chemical interplay between the q2DES and its environment, but also unlocks the possibility to couple multifunctional capping layers with the rich physics observed in two-dimensional electron systems, allowing the fabrication of new types of devices.

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures

We fabricate metal/LaAlO3/SrTiO3 heterostructures using a combination of pulsed laser deposition and in situ magnetron sputtering. Through magnetotransport and in situ X-ray photoelectron spectroscopy experiments, we investigate the interplay between electrostatic and chemical phenomena of the quasi two-dimensional electron gas formed in this system.

金属/LaAlO 的生长和静电/化学性质3/SrTiO3异

The quasi 2D electron system (q2DES) that forms at the interface between LaAlO3 (LAO) and SrTiO3 (STO) has attracted much attention from the oxide ...

Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides

Here, we present a procedure for the synthesis of bulk and thin film multicomponent (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (Co variant) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (Cu variant) entropy-stabilized oxides. Phase pure and chemically homogeneous (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (x = 0.20, 0.27, 0.33) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (x = 0.11, 0.27) ceramic pellets are synthesized and used in the deposition of ultra-high quality, phase pure, single crystalline thin films of the target stoichiometry. A detailed methodology for the deposition of smooth, chemically homogeneous, entropy-stabilized oxide thin films by pulsed laser deposition on (001)-oriented MgO substrates is described. The phase and crystallinity of bulk and thin film materials are confirmed using X-ray diffraction. Composition and chemical homogeneity are confirmed by X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The surface topography of thin films is measured with scanning probe microscopy. The synthesis of high quality, single crystalline, entropy-stabilized oxide thin films enables the study of interface, size, strain, and disorder effects on the properties in this new class of highly disordered oxide materials.

The synthesis of high quality bulk and thin film (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O entropy-stabilized oxides is presented.

组分变熵稳定氧化物的体积和薄膜合成

Here, we present a procedure for the synthesis of bulk and thin film multicomponent (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (Co variant) and ...

Fabrication of Schottky Diodes on Zn-polar BeMgZnO/ZnO Heterostructure Grown by Plasma-assisted Molecular Beam Epitaxy

Heterostructure field effect transistors (HFETs) utilizing a two dimensional electron gas (2DEG) channel have a great potential for high speed device applications. Zinc oxide (ZnO), a semiconductor with a wide bandgap (3.4 eV) and high electron saturation velocity has gained a great deal of attention as an attractive material for high speed devices. Efficient gate modulation, however, requires high-quality Schottky contacts on the barrier layer. In this article, we present our Schottky diode fabrication procedure on Zn-polar BeMgZnO/ZnO heterostructure with high density 2DEG which is achieved through strain modulation and incorporation of a few percent Be into the MgZnO-based barrier during growth by molecular beam epitaxy (MBE). To achieve high crystalline quality, nearly lattice-matched high-resistivity GaN templates grown by metal-organic chemical vapor deposition (MOCVD) are used as the substrate for the subsequent MBE growth of the oxide layers. To obtain the requisite Zn-polarity, careful surface treatment of GaN templates and control over the VI/II ratio during the growth of low temperature ZnO nucleation layer are utilized. Ti/Au electrodes serve as Ohmic contacts, and Ag electrodes deposited on the O2 plasma pretreated BeMgZnO surface are used for Schottky contacts.

Attainment of high-quality Schottky contacts is imperative for achieving efficient gate modulation in heterostructure field effect transistors (HFETs). We present the fabrication methodology and characteristics of Schottky diodes on Zn-polar BeMgZnO/ZnO heterostructures with high-density two dimensional electron gas (2DEG), grown by plasma-assisted molecular beam epitaxy on GaN templates.

等离子体辅助分子束外延法制备的锌极性 BeMgZnO/氧化锌异质结构肖特基二极管的制备

Heterostructure field effect transistors (HFETs) utilizing a two dimensional electron gas (2DEG) channel have a great potential for high speed device ...

Epitaxial Nanostructured &alpha;-Quartz Films on Silicon: From the Material to New Devices

In this work, we show a detailed engineering route of the first piezoelectric nanostructured epitaxial quartz-based microcantilever. We will explain all the steps in the process starting from the material to the device fabrication. The epitaxial growth of &#945;-quartz film on SOI (100) substrate starts with the preparation of a strontium doped silica sol-gel and continues with the deposition of this gel into the SOI substrate in a thin film form using the dip-coating technique under atmospheric conditions at room temperature. Before crystallization of the gel film, nanostructuration is performed onto the film surface by nanoimprint lithography (NIL). Epitaxial film growth is reached at 1000 &#176;C, inducing a perfect crystallization of the patterned gel film. Fabrication of quartz crystal cantilever devices is a four-step process based on microfabrication techniques. The process starts with shaping the quartz surface, and then metal deposition for electrodes follows it. After removing the silicone, the cantilever is released from SOI substrate eliminating SiO2 between silicon and quartz. The device performance is analyzed by non-contact laser vibrometer (LDV) and atomic force microscopy (AFM). Among the different cantilever&#8217;s dimensions included in the fabricated chip, the nanostructured cantilever analyzed in this work exhibited a dimension of 40 &#181;m large and 100 &#181;m long and was fabricated with a 600 nm thick patterned quartz layer (nanopillar diameter and separation distance of 400 nm and 1 &#181;m, respectively) epitaxially grown on a 2 &#181;m thick Si device layer. The&#160;measured&#160;resonance frequency was&#160;267 kHz and the estimated quality factor, Q, of the whole mechanical structure was Q ~ 398 under low vacuum conditions. We observed the voltage-dependent linear displacement of cantilever with both techniques (i.e., AFM contact measurement and LDV). Therefore, proving that these devices can be activated through the indirect piezoelectric effect.

Epitaxial Nanostructured &#945;-Quartz Films on Silicon: From the Material to New Devices

This work presents a detailed protocol for the microfabrication of nanostructured &#945;-quartz cantilever on a Silicon-On-Insulator(SOI) technology substrate starting from the epitaxial growth of quartz film with the dip coating method and then nanostructuration of the thin film via nanoimprint lithography.

硅上显性纳米结构α石英薄膜:从材料到新设备

In this work, we show a detailed engineering route of the first piezoelectric nanostructured epitaxial quartz-based microcantilever. We will explain all ...

Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing

Electrical, optical, and magnetic properties of oxide materials can often be controlled by varying the oxygen content. Here we outline two approaches for varying the oxygen content and provide concrete examples for tuning the electrical properties of SrTiO3-based heterostructures. In the first approach, the oxygen content is controlled by varying the deposition parameters during a pulsed laser deposition. In the second approach, the oxygen content is tuned by subjecting the samples to annealing in oxygen at elevated temperatures after the film growth. The approaches can be used for a wide range of oxides and nonoxide materials where the properties are sensitive to a change in the oxidation state.
The approaches differ significantly from electrostatic gating, which is often used to change the electronic properties of confined electronic systems such as those observed in SrTiO3-based heterostructures. By controlling the oxygen vacancy concentration, we are able to control the carrier density over many orders of magnitude, even in nonconfined electronic systems. Moreover, properties can be controlled, which are not sensitive to the density of itinerant electrons.

Oxide materials show many exotic properties that can be controlled by tuning the oxygen content. Here, we demonstrate the tuning of oxygen content in oxides by varying the pulsed laser deposition parameters and by performing postannealing. As an example, electronic properties of SrTiO3-based heterostructures are tuned by growth modifications and annealing.

通过生长和退火过程中的氧空位控制来调整氧化物性能

Electrical, optical, and magnetic properties of oxide materials can often be controlled by varying the oxygen content. Here we outline two approaches for ...