Rapid Manufacturing of Microwave Circuits on Low-cost Substrates using Laser Machining

Microwave and millimeter wave (MMW) planar structures are sensitive to printed circuit manufacturing tolerances. A promising alternative to the conventional photolithographic fabrication technique is laser structuring. This paper presents the study and the experiments conducted to investigate the possibility of employing low-cost commercially available substrates for microwave and MMW circuits using laser ablation process. At least two of such materials (a) glass reinforced ceramic filled teflon (PTFE) and (b) glass reinforced hydrocarbon have been used to design and fabricate microwave and MMW passive structures such as edge-coupled bandpass filter (BPF) using laser machining. The experimental results exhibit the suitability of glass reinforced hydrocarbon materials for microwave circuits employing laser ablation process. However, it is deduced that the laser ablation process alters the complex permittivity characteristics of the ceramic filled PTFE materials. The measured results of laser ablated passive structures on both materials are presented along with the simulation results.