Interest in gallium chalcogenides, i.e., gallium sulfide (GaS) and gallium selenide (GaSe), is growing rapidly due to its layered structure compatible with the fabrication of very thin layers by mechanical exfoliation and its wide band gap desirable for the design and fabrication of visible-UV optoelectronic devices. It is well known that the properties of these materials depend on their thickness; therefore, a facile and fast method is needed to infer the thickness of layered GaS and GaSe. Here, we report and validate a colorimetric method based on optical imaging for the quick and reliable quantitative determination of the thickness of exfoliated GaS and GaSe layers although it can be extended to other layered systems. For the validation of the method, the colorimetric computational estimate of the thickness is compared to the value obtained by atomic force microscopy. Further simulation of GaS and GaSe layers on different substrates of interest for different technological applications is provided as a quick guide for the rapid and reliable thickness determination of GaS and GaSe layers on various substrates.

中文翻译：

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快速可靠的比色反射计，用于通过光学显微镜确定低维 GaS 和 GaSe 剥离层的厚度

对镓硫属化物，即硫化镓 (GaS) 和硒化镓 (GaSe) 的兴趣正在迅速增长，因为其层状结构与通过机械剥离制造非常薄的层兼容，并且其宽带隙适合设计和制造可见光紫外光电器件。众所周知，这些材料的特性取决于它们的厚度；因此，需要一种简便快速的方法来推断层状 GaS 和 GaSe 的厚度。在这里，我们报告并验证了一种基于光学成像的比色方法，用于快速可靠地定量测定剥离的 GaS 和 GaSe 层的厚度，尽管它可以扩展到其他分层系统。为了验证方法，将厚度的比色计算估计值与原子力显微镜获得的值进行比较。提供了针对不同技术应用的不同衬底上的 GaS 和 GaSe 层的进一步模拟，作为快速可靠地确定各种衬底上 GaS 和 GaSe 层的厚度的快速指南。