Department of Mechanical Engineering, City University of Hong Kong, Kowloon, Hong Kong.
Department of Physics, National Changhua University of Education, Changhua 50007, Taiwan.
Science. 2021 Jan 1;371(6524):76-78. doi: 10.1126/science.abc4174.
Diamond is not only the hardest material in nature, but is also an extreme electronic material with an ultrawide bandgap, exceptional carrier mobilities, and thermal conductivity. Straining diamond can push such extreme figures of merit for device applications. We microfabricated single-crystalline diamond bridge structures with ~1 micrometer length by ~100 nanometer width and achieved sample-wide uniform elastic strains under uniaxial tensile loading along the [100], [101], and [111] directions at room temperature. We also demonstrated deep elastic straining of diamond microbridge arrays. The ultralarge, highly controllable elastic strains can fundamentally change the bulk band structures of diamond, including a substantial calculated bandgap reduction as much as ~2 electron volts. Our demonstration highlights the immense application potential of deep elastic strain engineering for photonics, electronics, and quantum information technologies.
钻石不仅是自然界中最硬的材料，还是一种极端的电子材料，具有超宽的能带隙、非凡的载流子迁移率和热导率。对钻石进行拉伸可以推动器件应用的这些极值性能。我们通过微加工制造出具有约 1 微米长度和 100 纳米宽度的单晶金刚石桥结构，并在室温下沿[100]、[101]和[111]方向实现了单轴拉伸载荷下的样品全宽均匀弹性应变。我们还展示了金刚石微桥阵列的深度弹性应变。这种超大、高度可控的弹性应变可以从根本上改变金刚石的体带结构，包括计算得出的约 2 电子伏特的显著带隙减小。我们的演示突出了深弹性应变工程在光子学、电子学和量子信息技术方面的巨大应用潜力。
