Current trends in material processing have seen a rise in the use of Gallium nitride ceramic substrate in components for power electronics, radar, 5G, and satellite communications.
While a viable replacement for silicon, GaN ceramic poses a challenge for traditional material processing, as it is commonly coated with micrometer-thin layers of metal—typically gold—that protect it from damage. Given the starkly different properties of both materials, traditional processing involves dicing the ceramic substrate and etching the metal layers in two separate steps.
However, the LPKF ProtoLaser R4 system can quickly process both material layers in a single, contactless, chemical-free process.
The LPKF ProtoLaser R4 system is capable of achieving or surpassing the tolerances of traditional manufacturing steps, while eliminating the need for a final cleaning of the material. The result is shorter processing times for small batch production or individual samples.
Processing Steps
An important aspect of laser cutting is its efficiency and accuracy. Operators can carefully adjust and optimize the laser energy for specific materials. The first step involves cutting the desired outline in the ceramic using high power, high pulse laser bursts, with the top gold layers acting as a shield against accumulated heat and ejected plasma.
The laser pulses provide both the highest speed processing and lowest thermal impact to the surrounding material, the so-called “cold ablation regime.” Cracks and chips in the ceramic are virtually nonexistent.
After cutting the ceramic, the ProtoLaser R4 vacuum table holds the sample firmly while laser power is reduced and tuned to etch the top gold layer. Next, using low energy pulses, the ProtoLaser R4 enables metal layers with features as small as 15 μm, with equally small spaces between them. The ProtoLaser R4’s air flow chamber and ultra-short pulsed ablation (which ejects very small particles) enables a process free of debris.
Single-Step Manufacturing
The LPKF ProtoLaser R4 provides a single-step manufacturing procedure for cutting and etching plated GaN ceramic structures. The optimized, ultra-short pulsed laser processing enables fast, clean, precise, chemical-free processing that is user-friendly. This supports applications that demand tight tolerance, reliable output, and fast turnaround due to frequent design changes.
This application is just one of the ProtoLaser R4’s rather unique applications, which also include cutting, drilling and structuring typical RF/ microwave materials, PTFE, double-sided flexible PCB laminates, and thin metal layers on glass.
Read the full article here:
https://www.microwavejournal.com/articles/34417-single-step-processing-of-plated-gan-substrates
