Through-Glass Vias (TGVs) are critical for advanced semiconductor packaging and heterogeneous integration, requiring high-density vertical interconnects for RF electronics, photonics and microfluidics. TGVs provide superior signal integrity, lower dielectric loss, and higher reliability compared to their silicon counterparts. While ultrafast laser processing is ideal for fabricating high-quality TGVs, maintaining micron-level process accuracy at high throughput remains a primary bottleneck, particularly when many thousands of TGVs are required per substrate. In many applications, the limiting factor is not the laser source itself, but the dynamic performance and synchronization of the motion system. By optimizing stage tuning and utilizing advanced control features such as ACS' ServoBoost and Learning Boost, trajectory-based accuracy comparisons are made between different motion and control systems to create 200 µm diameter TGVs in glass substrates with high-yield, uniform pitches and tight critical dimensions across large area glass substrates. After dialing in stage performance, an ultrafast laser platform (TLS Kanga) consisting of a 1030 nm femtosecond laser with fixed Bessel-beam optic is used to modify the internal structure of glass which is followed by chemical etching. By utilizing a high-dynamic linear-motor stage architecture and a high numerical aperture (NA) objective with a fixed beam approach, the system achieves superior positional accuracy (0.2 µm error) and throughput (9 holes /sec) compared to typical stages and controls (13.1 µm error and 4 hole/sec).
Keywords
- Acs
- Learning Boost
- Servoboost
- Tgv
- Through-Glass Via