Spectroscopic Studies of High Permittivity Materials

高介电常数材料的光谱研究

• 批准号: RGPIN-2017-04785
• 负责人: Crandles, David
• 金额: $ 1.53万
• 依托单位: Brock University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711218
• 关键词: Spectroscopic; Studies; Permittivity; Materials

High Permittivity materials are of great interest because of important existing applications in cell phone networks and potential applications in electrostatic energy storage devices (capacitors). To be of potential use in capacitors, a material will require "giant permittivity" that is temperature independent. To be of potential use in a dielectric resonator, which is a common component in cell phone networks, the energy "loss" must be minimized, while maintaining a reasonably high and temperature-independent permittivity. This research proposal will address fundamental questions regarding both of these applications. Since 2013, giant permittivity has been thought to have been observed in two novel materials: "co-doped oxides" in which the permittivity increase is due to “defect dipoles” and "high entropy oxides" in which the permittivity increase is not understood. Recent tests have suggested that the observation of giant permittivity in co-doped oxides is strongly affected by electrical contacts. The open question as to whether “defect dipoles” can actually increase permittivity will be studied using a contact-free technique in compensated silicon. If this mechanism is demonstrated, it may lead to the development of co-doped higher band gap materials which may be useful in energy storage. We will also perform tests in the high entropy oxides, to see if previous observations of giant permittivity made by measuring capacitance at low frequency are similarly affected by electrical contacts. Turning to dielectric resonator materials, note that the lowest loss material commonly used, the ordered perovskite BaMg1/3Ta2/3O3, is extremely expensive because it incorporates tantalum. Many researchers have proposed using niobium-based materials to replace expensive tantalum. However, the loss mechanisms in the niobium-based materials are poorly understood. For example, while the loss in BaMg1/3Nb2/3O3 has been predicted to be good enough for resonator applications, the losses observed in samples produced up to this point in time have been very large. Funds requested in this proposal will be used to perform a systematic study of dielectric loss in niobium-based dielectric resonator materials using a combination of x-ray diffraction and wide-frequency-range dielectric spectroscopy. The goal is to understand whether chemical composition and processing conditions can be slightly modified to decrease loss. Developing a niobium based material that could compete with tantalum based materials in terms of performance and price would be a significant and useful achievement.

高介电常数材料因其在手机网络中的重要现有应用以及在静电能量存储设备（电容器）中的潜在应用而受到极大关注，为了在电容器中具有潜在用途，材料将需要与温度无关的“巨大介电常数”。为了在介电谐振器（手机网络中的常见组件）中具有潜在用途，必须最大限度地减少能量“损失”，同时保持相当高且与温度无关的介电常数。本研究提案将解决有关介电常数的基本问题。自 2013 年以来，人们认为在两种新型材料中观察到了巨介电常数：“共掺杂氧化物”，其中介电常数增加是由于“缺陷偶极子”和“高熵氧化物”，其中介电常数增加。最近的测试表明，共掺杂氧化物中巨介电常数的观察受到电接触的强烈影响，而“缺陷偶极子”是否真的会增加这一悬而未决的问题。我们将使用补偿硅中的无接触技术来研究介电常数，如果这种机制得到证实，可能会导致共掺杂更高带隙材料的开发，该材料可能适用于能量存储。熵氧化物，看看以前通过测量低频电容进行的巨介电常数观察是否受到电接触的类似影响。转向介电谐振器材料，请注意常用的损耗最低的材料，即有序钙钛矿。 BaMg1/3Ta2/3O3 非常昂贵，因为它含有钽，许多研究人员建议使用铌基材料来替代昂贵的钽。然而，人们对铌基材料的损耗机制知之甚少。 BaMg1/3Nb2/3O3 预计足以满足谐振器应用的要求，但迄今为止在生产的样品中观察到的损耗非常大，该提案中要求的资金将非常大。结合 X 射线衍射和宽频范围介电光谱，可用于对铌基介电谐振器材料的介电损耗进行系统研究，目的是了解是否可以稍微修改化学成分和加工条件，以实现铌基介电谐振器材料的介电损耗。开发一种在性能和价格方面可与钽基材料竞争的铌基材料将是一项重大且有用的成就。