Introduction
Effective laser machining of a variety of materials requires a number of different wavelengths and pulse lengths, requiring different types of high power lasers. We have a number of high power laser systems, of 3 main types: Nd:YAG, CO2, and Ti:Sapphire, which cover a wide range of wavelengths (355 nm to 10.6 ?m) and pulse lengths (100 fs to 20 ms; also cw) and hence can process a very wide range of materials, including metals, glasses, polymers and ceramics. There is a general trade-off between precision and process speed, with long (ms) pulses providing relatively coarse but high speed machining, whilst very high precision can be achieved by the much slower processes with ns or fs pulses. Often excellent microprocessing results are achieved using a combination of laser systems and/or pulse regimes.
Micro-Engineering of Ceramics
PCB’s Microvia Drilling
The context of this research project is the pivotal importance of interconnection and assembly technologies within the entire electronics industry, particularly those techniques based on circuit boards. These are driven by rapid market expansion, the imperative for increased process speed, quality and efficiency, and ever-shrinking semiconductor devices of increasing functionality which will demand higher component densities on circuit boards in the future.
This research is concerned with delivering competitive advantage in the form of:
Fibre Delivery for Micromachining
Fibre Optic Micromachining
Microprocessing of Fused Silica
Ablation Process Characterisation
Shown below is detail of matrix from 50-300µs pulse duration for different values of irradiance
Short pulse duration:
=> Heat penetration depth << spot radius
=> Temperature controlled by energy
Long pulse duration:
=> Increased penetration depth, larger heated spot radius
=> Temperature controlled by power
Glass Micromachining Applications
Other Applications
Development of micro-machining processes for a wide variety of applications