In this work, we report on the fabrication and characterization of a miniature GaN chip with a size of 1.1×1.1×0.211.1\times 1.1\times0.21 mm3 for surface roughness measurement. Unlike conventional optical metrology that requires external components for the optical coupling between light source and detector, a monolithic GaN-on-sapphire chip fabricated through wafer-scale processes provides light emission and photodetection functions and is capable of sensing a range of average surface roughness from 0.025 to 1.6 μm1.6~\mu \text{m} . The sensing performances are compared with fiber-optic metrology, and the ability to real-time monitor the roughness of the moving surface is demonstrated. The novel chip offers the advantage of non-contact and non-destructive, compact structure, simple operation, and in situ measurement capability, which is highly valuable for various practical and industrial surface metrology applications.

中文翻译：

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用于表面粗糙度测量的微型 GaN 芯片


在这项工作中，我们报告了尺寸为 1.1×1.1×0.211.1\times 1.1\times0.21 mm3 的微型 GaN 芯片的制造和表征，用于表面粗糙度测量。与需要外部组件来实现光源和检测器之间光耦合的传统光学计量不同，通过晶圆级工艺制造的单片蓝宝石基氮化镓芯片提供光发射和光电检测功能，并且能够感测一系列平均表面粗糙度： 0.025 至 1.6 μm1.6~\mu \text{m} 。将传感性能与光纤计量进行比较，并展示了实时监测移动表面粗糙度的能力。该新型芯片具有非接触、无损、结构紧凑、操作简单、具有原位测量能力等优点，对于各种实际和工业表面测量应用具有很高的价值。