纳米制造 关键控制特性 第 6-7 部分：石墨烯 薄层电阻：van der Pauw 方法

[中文适用范围]： 本部分IEC TS 62607建立了一种确定关键控制特性的方法： - 薄层电阻R_S（以欧姆每平方Ω/sq测量） 通过范德堡方法（vdP）测量。 薄层电阻R_S是通过在平面样品边界上放置的四个电接触点进行四端电阻测量，并通过包含两个电阻测量的数学表达式计算得出。 - 本文件中描述的方法对石墨烯样品R_S的测量范围为10^-2 Ω/sq至10^4 Ω/sq。 - 该方法适用于CVD石墨烯，前提是将其转移到石英基板或其他绝缘材料（石英、Si上的SiO2）上，以及从碳化硅生长的石墨烯。 - 该方法是对在线四点探针法（4PP，IEC 62607-6-8）在薄层电阻测量方面的补充，适用于可以在样品边界上可靠放置接触点而不被4PP划伤的情况。 - 范德堡方法的结果与接触位置无关，前提是样品均匀，但石墨烯通常不符合这一条件。本文考虑了导电性分布不均匀的样品情况，并提出了一种将样品不均匀性作为R_S不确定度组成部分的方法。 [外文原描述]： IEC TS 62607-6-7:2023 establishes a method to determine the key control characteristics sheet resistance RS [measured in ohm per square (Ω/sq)], by the van der Pauw method, vdP. The sheet resistance RS is derived by measurements of four-terminal electrical resistance performed on four electrical contacts placed on the boundary of the planar sample and calculated with a mathematical expression involving the two resistance measurements. The measurement range for RS of the graphene samples with the method described in this document goes from 10−2 Ω/sq to 104 Ω/sq. The method is applicable for CVD graphene provided it is transferred to quartz substrates or other insulating materials (quartz, SiO2 on Si), as well as graphene grown from silicon carbide. The method is complementary to the in-line four-point-probe method (4PP, IEC 62607-6-8) for what concerns the measurement of the sheet resistance and can be applied when it is possible to reliably place contacts on the sample boundary, avoiding the sample being scratched by the 4PP. The outcome of the van der Pauw method is independent of the contact position provided the sample is uniform, which is typically not true for graphene at this stage. This document considers the case of samples with non-strictly uniform conductivity distribution and suggests a way to consider the sample inhomogeneity as a component of the uncertainty on RS.