Reconfigurable and Low-loss Millimeter-Wave Antennas using MEMS Paraffin Micro-actuators

使用 MEMS 石蜡微执行器的可重构低损耗毫米波天线

基本信息

批准号：
1408228
负责人：
Nima Ghalichechian
金额：
$ 36.37万
依托单位：
Ohio State University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2014
资助国家：
美国
起止时间：
2014-08-01 至 2018-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1408228&HistoricalAwards=false
关键词：
Reconfigurable Low loss Millimeter Wave

项目摘要

Reconfigurability is an essential feature in future agile millimeter wave (30-300 GHz) systems used in sensing, imaging, wireless, and satellite communications. Antennas and radio frequency (RF) circuits are an integral part of such systems as they can provide changes in polarization, bandwidth, beam steering, gain, radiation pattern or characteristic impedance control, among others. In the past, key devices for achieving reconfiguration have been RF MEMS switches. However, these devices suffer from high actuation voltage, lack of integration flexibility, reliability, and high cost. In this proposal we introduce a new class of novel materials and devices to achieve reconfiguration without those shortcomings. Specifically, we consider paraffin phase-change materials (PPCMs) as a promising candidate. Owed to the natural reconfigurability and low-loss architecture of our proposed PPCM devices, we expect them to have wide utility in sensing, imaging, and wireless/satellite communication systems. Educational impacts include hands-on experiences to train students in material characterization, multi-physics finite element simulation, device fabrication, and RF testing through summer camps and a variety of outreach activities to attract undergrads and underrepresented students in engineering. Impact on society (community) include: (1) reliable high bandwidth handhelds and communication systems for large data rate transfers, and (2) a new class of reliable switchable devices that rely on low-cost, low voltage/power and low temperature manufacturing for ease of integration in future wireless and communication devices.Paraffin is a novel low loss dielectric that undergoes reversible volumetric mechanical phase change. This is in contrast to electrical phase change (permittivity and conductivity) of other phase-change materials. We propose reconfigurable millimeter wave antennas and RF circuits that employ paraffin film to develop a new class of paraffin-based phase change materials having two complimentary functions: (1) low-loss operation, and (2) highly localized thermo-mechanical micro actuation. PPCMs should allow the long standing goal of developing low-loss millimeter wave and RF circuits and antennas on a single chip. In the past, low temperature co-fired ceramics have been used but require sintering at extremely high temperatures, making them incompatible with semiconductor processing. Furthermore, they are not reconfigurable. By contrast, paraffin is known to undergo a 15% volumetric change at relatively low temperatures. Also, PPCMs exhibit a dielectric loss as low as 0.0002. As part of this effort, for the first time, we propose to demonstrate the feasibility of paraffin-based PCMs for passive and reconfigurable millimeter wave antennas and RF tuning circuits. The proposed PPCMs have the following key features: (1) extremely low dielectric loss, (2) exploit phase-change properties to function as thermo-mechanical actuators across a large bandwidth , (3) can be integrated monolithically on the same substrate to enable continuous reconfiguration. These PPCM devices not only avoid reliability issues of conventional devices, but also provide for very low-loss and continuous reconfiguration. As part of this research, we will study the material and electrical properties of PPCM, develop devices and examine their integration into millimeter wave antenna arrays and impedance matching circuits.

可重构性是未来用于传感、成像、无线和卫星通信的敏捷毫米波 (30-300 GHz) 系统的一项基本功能。天线和射频 (RF) 电路是此类系统不可或缺的一部分，因为它们可以提供偏振、带宽、波束控制、增益、辐射方向图或特性阻抗控制等方面的变化。过去，实现重构的关键器件是 RF MEMS 开关。然而，这些器件存在驱动电压高、缺乏集成灵活性、可靠性和高成本的问题。在本提案中，我们引入了一类新型材料和设备来实现重新配置，而没有这些缺点。具体来说，我们认为石蜡相变材料（PPCM）是一种有前途的候选材料。由于我们提出的 PPCM 器件的自然可重构性和低损耗架构，我们期望它们在传感、成像和无线/卫星通信系统中具有广泛的用途。教育影响包括通过夏令营和各种外展活动来培训学生材料表征、多物理有限元模拟、设备制造和射频测试方面的实践经验，以吸引工程领域的本科生和代表性不足的学生。对社会（社区）的影响包括：（1）用于大数据速率传输的可靠高带宽手持设备和通信系统，以及（2）依赖于低成本、低电压/功率和低温制造的新型可靠可切换设备以便于集成到未来的无线和通信设备中。石蜡是一种新型低损耗电介质，可经历可逆的体积机械相变。这与其他相变材料的电相变（介电常数和电导率）形成对比。我们提出了可重构的毫米波天线和射频电路，它们采用石蜡薄膜来开发一种新型石蜡基相变材料，该材料具有两种互补功能：(1) 低损耗操作，(2) 高度局部化的热机械微驱动。 PPCM 应该实现在单芯片上开发低损耗毫米波和射频电路和天线的长期目标。过去曾使用低温共烧陶瓷，但需要在极高温度下烧结，这使得它们与半导体加工不兼容。此外，它们不可重新配置。相比之下，石蜡在相对较低的温度下会发生 15% 的体积变化。此外，PPCM 的介电损耗低至 0.0002。作为这项工作的一部分，我们首次建议展示石蜡基相变材料用于无源和可重构毫米波天线和射频调谐电路的可行性。所提出的 PPCM 具有以下主要特征：(1) 极低的介电损耗，(2) 利用相变特性在大带宽内充当热机械致动器，(3) 可以单片集成在同一基板上，以实现持续重新配置。这些 PPCM 器件不仅避免了传统器件的可靠性问题，而且还提供非常低的损耗和连续的重新配置。作为这项研究的一部分，我们将研究 PPCM 的材料和电气特性，开发设备并检查它们与毫米波天线阵列和阻抗匹配电路的集成。