Ultra Precision Hybrid Laser-FIB Platform – Mr Chris Wright
The aim is to produce an integrated processing route which uses ultrafast lasers and focused ion beams to increase the throughput of ultra-precision manufacturing. The main focus of this body of work is to develop the ultrafast laser machining platform into a non-contact ultra-precision machine tool with inbuilt metrology for a closed loop machining. To further the integrated processing route a proof of concept for cross-platform processing will be carried out towards the end of the project.
Combining these two technologies has the potential for three key advantages:
- Higher degree of flexibility compared to more established technologies
- Reduced production time for device prototyping, continuous customisation or low volume devices
- Laser processing has a significantly higher material removal rate than FIB milling which increases throughput for a large range in feature sizes from nm to mm
However, there are a number of issues with developing the proposed system:
- Nature of lasers is that they are inherently unstable which reduces the overall performance of the system
- Currently laser processed devices have to be removed from tool to be measured which makes reworking difficult
- Using the two platforms as an integrated machine tool hasn’t been carried out previously
- FIB milling hasn’t been used as a machine tool previously although this isn’t the primary focus
- Closed-loop milling of 3D features using ultrafast hasn’t been performed previously The different metrology systems need to be developed for different use cases
The current phase of development is determining the performance of the laser system and developing control strategies to stabilise the laser with respect to power, diameter and pointing stability to increase the accuracy of the ultrafast platform. This will lead into development of the inbuilt metrology systems for closed loop laser processing. Initially starting with 2D profiles moving on towards 2.5D manufacture finalising with a fully 3D system.
This research project is being undertaken at the University of Cambridge under the supervision of Prof Bill O’Neill.