Integration of Novel Materials with Silicon Chips Makes New ‘Smart’ Devices Possible
For Immediate Release
来自北卡罗来纳州立大学和美国陆军研究办公室的研究人员已开发出一种将新型功能材料整合到计算机芯片上的方法，从而可以创建新的智能设备和系统。
封面图像经Appl的许可重印。物理。Lett。61，1290–1292（1992）。版权1992 AIP Publishing LLC。
The novel functional materials are oxides, including several types of materials that, until now, could not be integrated onto silicon chips: multiferroic materials, which have both ferroelectric and ferromagnetic properties; topological insulators, which act as insulators in bulk but have conductive properties on their surface; and novel ferroelectric materials. These materials are thought to hold promise for applications including sensors, non-volatile computer memory and microelectromechanical systems, which are better known as MEMS.
“这些新颖的氧化物通常是在与计算设备不兼容的材料上生长的，” NC State的John C.粉丝杰出材料科学与工程主席兼描述该作品的论文的人Jay Narayan说。“我们现在能够将这些材料集成到硅芯片上，从而使我们能够将它们的功能纳入电子设备。”
研究人员开发的方法使他们能够将材料集成到两个平台上，这两种平台都与硅：硝酸钛平台兼容，可与基于氮化物的电子产品一起使用。和Yttria稳定的氧化锆，用于基于氧化物的电子产品。
Specifically, the researchers developed a suite of thin films that serve as a buffer, connecting the silicon chip to the relevant novel materials. The exact combination of thin films varies, depending on which novel materials are being used.
例如，如果使用多效材料，研究人员将使用四种不同薄膜的组合：硝酸钛，氧化镁，氧化镁和兰谷质黄锰氧化物。但是对于拓扑绝缘子，它们将仅使用两层薄膜的组合：氧化镁和硝酸钛。
These thin film buffers align with the planes of the crystalline structure in the novel oxide materials, as well as with the planes of the underlying substrate – effectively serving as a communicating layer between the materials.
This approach, called thin film epitaxy, is based on the concept of domain-matching epitaxy, and was first proposed by Narayan in2003年的论文。
“将这些新型材料整合到硅芯片上使许多事情成为可能，” Narayan说。“例如，这使我们能够感知或收集数据；操纵该数据；并计算一个响应 - 全部在一个紧凑的芯片上。这使得设备更快，更高效，更轻。”
Another possible application, Narayan says, is the creation of LEDs on silicon chips, to make “smart lights.” Currently, LEDs are made using sapphire substrates, which aren’t directly compatible with computing devices.
“We’ve already patented this integration technology, and are currently looking for industry partners to license it,” Narayan says.
The paper, “Multifunctional epitaxial systems on silicon substrates,” is published online in the journal应用物理评论。该论文的主要作者是北卡罗来纳州州立大学的博士后研究员Srinivasa Singamaneni，他也隶属于陆军研究办公室。该论文由陆军研究办公室的约翰·普拉特（John Prater）合着，他还是北卡罗来纳州立大学材料科学与工程学的兼职教授。这项工作得到了陆军研究办公室在赠款号W911NF-04-D-0003的支持下的支持，并在NC State的分析仪器设施的技术支持下完成。
-shipman-
Note to Editors:研究摘要如下。
“硅底物上的多功能外延系统”
作者：Srinivasa Rao Singamaneni和J. T. Prater，北卡罗来纳州立大学和陆军研究办公室；北卡罗来纳州立大学的J. Narayan
出版：7月18日，应用物理评论
DOI：10.1063/1.4955413
Abstract:Multifunctional heterostructures can exhibit a wide range of functional properties, including colossal magneto-resistance, magnetocaloric, and multiferroic behavior, and can display interesting physical phenomena including spin and charge ordering and strong spin-orbit coupling. However, putting this functionality to work remains a challenge. To date, most of the work reported in the literature has dealt with heterostructures deposited onto closely lattice matched insulating substrates such as DyScO3，srtio3（STO）或使用晶格匹配外观（LME）概念的STO缓冲SI（100）。但是，LME生长的异质结构的应变通常并不完全放松，并且这些层包含有害缺陷，例如螺纹位错，这些位错可显着降低膜的物理特性并对设备特性产生不利影响。此外，大多数底物与现有基于CMOS的技术不兼容，其中SI（100）底物占主导地位。这篇综述讨论了将多功能氧化物和非氧化物材料整合到硅底物上的最新进展。提出了一种替代性薄膜生长方法，称为“域匹配外延”，该方法识别出最大程度地减少晶格菌株和不需要的不合适系统（7％–25％及更高）的方法的方法。这种方法广泛地允许将多功能材料集成到硅底物上，从而可以将传感，计算和响应功能组合起来以生成下一代“智能”设备。通常，脉冲激光沉积已被用来外恋种植这些材料，尽管此处开发的概念也可以扩展到其他沉积技术。可以证明，锡和Yttria稳定的氧化锆模板层为将新功能集成到基于硅的计算机芯片中提供了有希望的平台。这篇评论论文报告了许多涉及各种铁电，多效，磁性，光催化和智能材料的薄膜异质结构系统。它们的性质已经进行了广泛的研究，并且发现其功能与该领域研究人员先前报道的单晶氧化物底物上生长的膜相当。 In addition, this review explores the utility of using laser processing to introduce stable defects in a controlled way and induce magnetism and engineer the optical and electrical properties of nonmagnetic oxides such as BaTiO3, VO2, NiO, and TiO2作为将其他磁性和导电层纳入结构的替代方法。这些重要的材料进步预示着与CMOS兼容的多功能设备中令人兴奋的新进步。
