The Study of Crystalline Orientation and Interface Thermal Conductance of Mechanical Exfoliated Black Phosphorus with Raman-based Techniques

Abstract

Black phosphorus is a new two-dimensional material that has attracted worldwide interests. In this work, the exfoliated few-layered BP samples are fabricated on Si substrate. The crystalline orientation of these samples is identified with the optothermal Raman spectroscopy. The interface thermal conductance between fewlayered BP samples and its adjacent Si substrate is measured with the micro-Raman spectroscopy. BP samples with thicknesses between 16.6 and 113.7 nm are characterized in a temperature range of 223 to 229 K. These data make it possible to explore the temperature dependence and thickness dependence of interface thermal conductance. In fact, we have observed high interface thermal conductance with strong temperature dependence but weak or no thickness dependence. The underlying physical mechanisms of these observations are explored and discussed thoroughly.