论文标题
晶圆刻度立方硅碳化物晶体的高热电导率
High Thermal Conductivity in Wafer Scale Cubic Silicon Carbide Crystals
论文作者
论文摘要
高热电导率电子材料是用于高性能电子和光子设备的关键组件,作为主动功能材料或热管理材料。我们报告在室温下以高质量的晶片尺度立方硅(3C-SIC)晶体在室温下500 W m-1k-1的各向同性高热电导率,这是大晶体中第二高的晶体(仅钻石超过)。此外,发现相应的3C-SIC薄膜具有创纪录的平面内和跨平面导电性,甚至比具有等效厚度的钻石薄膜高。我们的结果解决了一个持久的难题,即3C-SIC的热导率的文献值比结构上更复杂的6H-SIC低迷。进一步的分析表明,这项工作中观察到的高热电导率是由3C-SIC晶体的高纯度和高晶体质量引起的,这些晶体排除了3C-SIC中异常强的缺陷 - 光散射。此外,通过通过外延生长将3C-SIC与其他半导体整合在一起,我们表明测得的3C-SIC-SI TBC是半导体界面的最高之一。这些发现不仅为基本声子传输机制提供了见解,还表明3C-SIC可能构成了极好的宽带gap半导体,用于将电力电子作为活性组件或底物应用。
High thermal conductivity electronic materials are critical components for high-performance electronic and photonic devices as either active functional materials or thermal management materials. We report an isotropic high thermal conductivity over 500 W m-1K-1 at room temperature in high-quality wafer-scale cubic silicon carbide (3C-SiC) crystals, which is the second highest among large crystals (only surpassed by diamond). Furthermore, the corresponding 3C-SiC thin films are found to have record-high in-plane and cross-plane thermal conductivity, even higher than diamond thin films with equivalent thicknesses. Our results resolve a long-lasting puzzle that the literature values of thermal conductivity for 3C-SiC are perplexingly lower than the structurally more complex 6H-SiC. Further analysis reveals that the observed high thermal conductivity in this work arises from the high purity and high crystal quality of 3C-SiC crystals which excludes the exceptionally strong defect-phonon scatterings in 3C-SiC. Moreover, by integrating 3C-SiC with other semiconductors by epitaxial growth, we show that the measured 3C-SiC-Si TBC is among the highest for semiconductor interfaces. These findings not only provide insights for fundamental phonon transport mechanisms, also suggest that 3C-SiC may constitute an excellent wide-bandgap semiconductor for applications of power electronics as either active components or substrates.