Phase Change Memory Materials via Non-Aqueous Electrodeposition into Nano-structured Templates

通过非水电沉积成纳米结构模板的相变记忆材料

• 批准号: EP/I010890/1
• 负责人: G Reid
• 金额: $ 116.82万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FI010890%2F1
• 关键词: Phase; Change; Memory; Materials; via

This project is concerned with developing non-aqueous electrochemical methods and suitably tailored reagents to facilitate spatially selective electrodeposition of binary (e.g. In2(Se,Te)3, Sb2(Se,Te)3, Ge(Se,Te)) and the ternary chalcogenide materials (e.g. Ge2Sb2Te5, doped Sb2Te3) for applications in solid-state phase change memory (PCM). The key objectives are to demonstrate successful deposition of the target materials inside nano-scale (down to 2 nm) confined cell structures and to establish the effect of down-scaling pore size on the deposition process. Successful electrodeposition of well-defined compound semiconductor alloy compositions of these types will provide a significant new enabling technology which could also have a major impact on the other applications requiring semiconductor alloy deposition on a nano-scale. Using non-aqueous solvents (such as MeCN, propylene carbonate or chlorofluorocarbons) will bring several advantages over aqueous processes:(i) the use of a much wider range of reagents which can be tailored to the application;(ii) access to more reactive alloy compositions;(iii) a wider range of deposition potentials,while these solvents are more readily available, less expensive, much more easy to purify and less viscous (important for penetrating narrow. high aspect-ratio pores) than for example ionic liquids.These chalcogenide alloys are of major interest for phase change memory (PCM) materials - an emerging technology for non-volatile memory which is expected to compete with (and even replace) FLASH memory in specialist and everyday consumer electronics. Production of these alloys by electrodeposition could bring several advantages over current methods of production (mainly PVD), since it allows spatially selective deposition (since the materials are only deposited on the electrode surface), filling the pores of the templates from the bottom, hence enabling complete filling even of very narrow nanopores - leading to a very significant reduction of the dimensions of each individual cell, and hence potentially much higher cell density. In turn this will lead to faster switching between the crystalline and non-crystalline phases, leading to smaller devices and greater energy efficiency. To achieve these targets requires a multidisciplinary approach involving several key contributions: (i) to develop (and refine) new tailored molecular compounds (electrochemical reagents) with elements from the p-block (gallium, indium, germanium, antimony) in combination with groups containing the chalcogens i.e. the elements selenium and tellurium; (ii) to use these as reagents for the growth of the binary & ternary alloy materials by electrochemical deposition into nano-structured silica or alumina templates comprised of very narrow parallel pores with well-defined diameters between 1000 nm and 2 nm; (iii) characterisation of the deposited materials to determine the element ratios present (composition), their crystal structures, and phase change properties;(iv) deposition of the 'best' compositions into well-defined pores on a chip array to allow switching of the arrays memory cells in an actual device, hence demonstrating the true potential of this new approach.The team of investigators brings together a complementary and internationally unique set of skills and expertise to achieve these targets, while the input from our Project Partners, Ilika Technologies Ltd will add considerable value to the project.

本项目主要研究非水溶液电化学方法和合适的电化学试剂，以促进二元（如In 2（Se，Te）3，Sb 2（Se，Te）3，Ge（Se，Te））和三元硫族化合物材料（如Ge 2 Sb 2 Te 5，掺杂Sb 2 Te 3）在固态相变存储器（PCM）中的空间选择性电沉积。关键目标是展示纳米级（低至2 nm）受限细胞结构内的靶材料的成功沉积，并建立缩小孔径对沉积过程的影响。这些类型的明确定义的化合物半导体合金组合物的成功电沉积将提供一种重要的新的使能技术，该技术也可以对需要纳米级半导体合金沉积的其它应用产生重大影响。使用非水溶剂（例如MeCN、碳酸亚丙酯或氯氟烃）将带来优于水性方法的若干优点：（i）使用可针对应用定制的范围宽得多的试剂;（ii）获得更具反应性的合金组合物;（iii）更宽范围的沉积电位，同时这些溶剂更容易获得、更便宜、更容易纯化且粘度更低（对于渗透窄的材料是重要的）。这些硫属化合物合金是相变存储器（PCM）材料的主要兴趣所在，相变存储器（PCM）材料是一种新兴的非易失性存储器技术，预计将与专业和日常消费电子产品中的闪存竞争（甚至取代）。通过电沉积生产这些合金可以带来优于当前生产方法的几个优点（主要是PVD），因为它允许空间选择性沉积（因为材料仅沉积在电极表面上），从底部填充模板的孔，因此能够完全填充甚至非常窄的纳米孔-导致每个单独电池的尺寸非常显著地减小，并因此潜在地具有高得多的细胞密度。反过来，这将导致晶相和非晶相之间的更快切换，从而导致更小的器件和更高的能效。为了实现这些目标，需要采取多学科的办法，其中涉及若干关键贡献：（并提炼）新的定制分子化合物（电化学试剂）与P区元素（镓、铟、锗、锑）与含有硫属元素即元素硒和碲的基团的组合;（ii）使用这些作为用于二元和三元合金材料通过电化学沉积生长成纳米结构的二氧化硅或氧化铝模板的试剂，所述纳米结构的二氧化硅或氧化铝模板由具有1000 nm和2 nm之间的明确限定的直径的非常窄的平行孔组成;（iii）表征沉积材料以确定存在的元素比率（组成）、它们的晶体结构和相变性质;（iv）将“最佳”组合物沉积到芯片阵列上明确限定的孔中以允许在实际器件中切换阵列存储单元，从而证明了这种新方法的真正潜力。调查小组汇集了一套互补的、国际上独特的技能和专门知识来实现这些目标，而我们的项目合作伙伴Ilika Technologies Ltd的投入将为该项目增加相当大的价值。

项目成果

Controlling the nanostructure of bismuth telluride by selective chemical vapour deposition from a single source precursor

• DOI: 10.1039/c4ta00341a
• 发表时间: 2014-03
• 期刊: Journal of Materials Chemistry
• 作者: Sophie L. Benjamin;C. K. de Groot;Chitra Gurnani;Andrew L. Hector;R. Huang;E. Koukharenko;W. Levason;G. Reid

Low Pressure Chemical Vapour Deposition of Crystalline Ga2Te3 and Ga2Se3 Thin Films from Single Source Precursors Using Telluroether and Selenoether Complexes

使用碲醚和硒醚配合物从单源前驱体低压化学气相沉积结晶 Ga2Te3 和 Ga2Se3 薄膜

• DOI: 10.1016/j.phpro.2013.07.056
• 发表时间: 2013
• 期刊: Physics Procedia
• 作者: George K

Unexpected neutral aza-macrocycle complexes of sodium.

意外的中性钠氮杂大环配合物。

• DOI: 10.1039/c4cc01407c
• 发表时间: 2014
• 期刊: Chemical communications (Cambridge, England)
• 作者: Everett M

Highly Selective Chemical Vapor Deposition of Tin Diselenide Thin Films onto Patterned Substrates via Single Source Diselenoether Precursors

• DOI: 10.1021/cm302864x
• 发表时间: 2012-11-27
• 期刊: CHEMISTRY OF MATERIALS
• 影响因子: 8.6
• 作者: de Groot, C. H. (Kees);Gurnani, Chitra;Reid, Gillian
• 通讯作者: Reid, Gillian

Non-aqueous electrodeposition of p-block metals and metalloids from halometallate salts

• DOI: 10.1039/c3ra40739j
• 发表时间: 2013-01-01
• 期刊: RSC ADVANCES
• 影响因子: 3.9
• 作者: Bartlett, Philip N.;Cook, David;Reid, Gillian
• 通讯作者: Reid, Gillian