The Development of Nanoelectromechanical Structures for GHz Oscillators and Other High Frequency Devices

电子设备的日益小型化是电子革命的基础。在执行装置领域也出现了类似的趋势。其中，“微机电系统”正迅速被“纳米机电系统”（NEMS）所取代。这种装置的终极尺度将是原子尺度。纳米工程材料将成为这类器件的基本材料[j]。在这些材料中。纳米管（NTs）提供了NFMS所需的许多必要特性：它们的几何形状、非凡的机械特性[2-6]（这将允许GI-Iz机械共振）、新颖的电子特性（金属、半导体）[7-9]。新的界面性能（原子光滑，低摩擦）110,llj。我们最近发现了纳米管触点[12]的运动（摩擦）[1 I]和电学性质的原子尺度特征。在纳米管之间的动态电接触中，这些在原子尺度上测量的响应变化允许许多新颖的器件。这些包括高频设备，其中调制信号取决于滑动触点的相对速度，到原子尺度线性编码器，其中系统的相对运动可以测量到一个单元间距内。部署基于NT的NEMS的必要技术将是批量制造过程，其中包括NT集成。这个问题的一个解决方案是通过NT生长过程。其中催化剂材料在衬底上图案化以产生所需的集成NI' NEMS。具体地说，必须理解生长过程，使具有特定晶体取向、半径和长度的纳米管能够在集成硅基器件结构内平面生长。我们提出了一个研究计划，结合了对新型NEMS器件基本机制的研究，以及在批量制造NT NEMS方面取得进展的生长技术。我们考虑的特定NEMS器件利用了NT电引线之间动态接触的原子尺度特征，以及NT的机械共振特性。我们认为，电触点的位置和方向依赖是NEMS器件值得关注的一个方面。这是纳米尺度的独特性质，应该开辟独特的NEMS设备应用。在微米尺度的接触中，输运性质是许多相对晶体取向的接触面和缺陷等的平均值，在纳米尺度的接触中。由于接触面[13]的相对完美和光滑以及THC精确调整接触原子晶格相对取向的能力，将观察到NCW行为。在这种情况下，原子结构很重要。我们建议创造：1；电压-频率转换器。根据输入幅度，（M1-lz-GI-Iz）驱动信号将被召集为1- 1000倍于输入频率的信号2。千兆赫混频器：从输入M1-Iz信号中产生和频和差频。原子分辨率线性编码器中的一个集成。亚微米设备。

The increasing miniaturization of electronic devices has been the foundation of the electronics revolution. Similar trends ate being seen in the field of actuating devices. where the acronym MicroElectroMechanical Systems is quickly' being replaced at its leading edge by NanoElectroMechanical Systems (NEMS). The ultimate scate for such devices will be the atomic scale. Nanoscale engineered materials will the building blocks of such devices [I]. Among these materials. nanotubes (NTs) provide many of the necessary properties required for NFMS: their geometry, extraordinary mechanical properties [2-6] ( which will allow GI-Iz mechanical resonance), novel electronic properties (metallic, semiconducting) [7-9]. and novel interfacial properties (atomically smooth, low friction)110, llj. We have recently discovered the atomic scale features in both the motion (friction)[1 I] and electrical properties of nanotube contacts [12]. These measured changes in response at the atomic scale in the dynamic electrical contact between NTs allow for a host of novel devices. These include high frequency devices, where the modulated signal depends on the relative velocity of the sliding contact, to atomic scale linear encoders in which the relative movement of a system can be measured to within a unit cell spacing. A necessary technology in the deployment of NT based NEMS will be a batch-fabrication process which includes NT integration. One solution to this problem is through NT growth processes. in which catalyst material is patterned on a substrate to produce desired integrated NI' NEMS. Specifically, growth processes will have to be understood such that NTs of specific crystalline orientation, radius, and length can be grown in-plane within an integrated silicon based device structure. We propose a plan of research that combines both investigations into the basic mechanisms of novel NEMS devices, and growth techniques that make strides toward batch-fabrication of NT NEMS. The specific NEMS devices we have in mind exploit the atomic scale features of the dynamic contact between NT electrical leads, and the mechanical resonance properties of NTs. Ln our view, the idea of position and orientation dependence of electrical contacts is an aspect of NEMS devices that deserves attention. It is a unique property of the nanometer scale and should open up device applications that are unique to NEMS. In a micron scale contact, the transport properties are an average over many relative crystalline orientations of the contacting surfaces as well as defects etc. hi a nanometer scale contact. ncw behavior will be observed due to relative perfection and smoothness of the contacting surfaces [13] and thc ability to tune precisely the relative orientation of contacting atomic lattices. hi this case the atomic structure matters. We propose to create:1. Voltage to frequency converter. The (M1-lz-GI-Iz) driving signal will be convened to a signal with 1- 1000 times the input frequency depending on the input amplitude2. Gigahertz frequency mixer: Sum and difference frequencies will be generated from input M1-Iz signals3. Atomic resolution linear encoder in an integrated. submicron device.