发表机构
The Institute of Science Tokyo; Swinburne University of Technology; Melbourne Center for Nanofabrication (MCN); Vilnius University; Institute of Innovative Research, Institute of Science Tokyo（东京科学大学; 斯威本科技大学; 墨尔本纳米制造中心; 维尔纽斯大学; 东京科学大学创新研究院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过实验比较平坦硅与垂直及倾斜纳米针黑硅在2.45 GHz微波下的加热行为，发现纳米针取向影响加热效率和腔体响应，揭示了取向相关的有效介电常数及双折射效应。
AI 中文摘要
硅在微波2.45 GHz频段具有高反射率和可忽略的吸收，但当其通过SF6/O2等离子体刻蚀形成具有纳米针表面纹理的黑硅时，可以被加热。在圆柱形TM010谐振腔中，在相同条件下比较了平坦硅、具有垂直纳米针的黑硅和具有倾斜（取向）纳米针的黑硅的微波加热情况。样品水平放置在150微米厚的盖玻片上，这使它们在腔内的水平和位置标准化，并允许辐射温度计针对K型热电偶进行共同校准。在仅2-3-4 W微波功率的阶梯式方案（每步60秒）下，具有垂直针的黑硅达到约260°C，系统性地超过平坦硅（约190°C），而具有取向针的黑硅在3 W时表现出延迟但突然的加热起始。腔谐振的原位监测显示，所有样品的谐振频率f下移2-3 MHz，且该漂移在样品温度超过约120-150°C时一致出现，与硅中热激活载流子产生一致。在给定温度下，每个样品以不同的f和品质因数Q加载腔体，表明纳米针阵列的取向相关有效介电常数，这与倾斜黑硅的强形式双折射一致。讨论了定量温度和介电常数确定的应用潜力和挑战。
英文摘要
Silicon, which is highly reflective and has negligible absorption at the microwave 2.45 GHz range, can be heated when it is turned into black-Si with a surface texture of nano-needles made by SF6/O2 plasma etching. Microwave heating of flat Si and of black-Si with vertical and with tilted (oriented) nano-needles was compared under identical conditions in a cylindrical TM010 resonator. Samples were placed horizontally on a 150-micrometer-thick cover glass, which standardized their height and position inside the cavity and allowed a common calibration of the radiation thermometer against a K-type thermocouple. Under a stepwise protocol of only 2-3-4 W of microwave power (60 s per step), black-Si with vertical needles reached ~ 260 C, systematically exceeding flat Si (~ 190 C), while black-Si with oriented needles showed a delayed but abrupt onset of heating at 3 W. In situ monitoring of the cavity resonance revealed a 2-3 MHz downshift of the resonance frequency f for all samples, with the drift consistently appearing once the sample temperature exceeded ~ 120 - 150 C, consistent with thermally activated carrier generation in Si. At a given temperature, each sample loads the cavity at a different f and quality factor Q, indicating an orientation-dependent effective permittivity of the nano-needle array, in line with the strong form birefringence of tilted black-Si. Application potential and challenges in the quantitative temperature and permittivity determination are discussed.
Comments14 pages, 6(main) and 3(supplement) figures
