**4. Conclusion**

The challenges and advancements in micromilling of high-frequency RF& Terahertz devices illustrate the ever-changing nature of this field. While challenges like dimensional accuracy, tool wear, and material compatibility still persist, innovative tooling, monitoring systems, simulation software, multi-axis systems, and hybrid approaches are advancing at rapid ratesto and increasing micromilling capabilities. These advances will continually enhance the precision and quality of high-frequency RF & TeraHertz devices, driving progress in modern communication and sensing systems.

*Micromachining – New Trends and Applications*
