Laser Micromachining and Characterization of Metal-on-Glass High Density Pitch Adapters

Pitch adapters (PAs) are passive electronic components widely used to adapt different pitches between silicon strip detectors and readout electronics. This paper presents an optimized process to fabricate high-density PAs using laser ablation of metal-on-glass layers. Minimum pitch sizes of 40 μm for the pads and 25 μm for the conductive traces were achieved. The resolution of the method allowed the cutting of traces as narrow as 15 μm. Different prototypes and small production series have been successfully manufactured and tested for electrical parameters, bondability, and metrology. Ageing tests were also performed to ensure long-term reliability. The production yield reached 80%. Fully functional particle detectors for high-energy physics have been assembled using these PAs, characterized and tested with lasers and radioactive sources.