Excimer Laser Technology

Process

An Excimer Laser is a powerful form of laser which generates nanosecond pulses, and is nearly always operated in the ultraviolet (UV) spectral region. The excimer gain medium is a gas mixture, typically containing a rare gas (such as argon, krypton, or xenon) and a halogen (fluorine or chlorine, often HCl), in addition to helium and/or neon as a buffer gas.

The UV light from an excimer laser is well absorbed by biological matter and organic compounds. Rather than burning or cutting material, the excimer laser adds enough energy to disrupt the molecular bonds of the surface and effectively disintegrates it in a tightly controlled manner through ablation.

The short wavelengths in excimer's ultraviolet spectral region make possible a number of applications, including:

• Generation of very fine patterns with photo-lithographic methods (micro-lithography), such as in semiconductor chip production and micro-medical applications
• Pulsed laser deposition for fabricating thin films of various materials
• Laser marking and micro-structuring of glasses and plastics
• Other materials processing requiring very short absorption lengths of only micrometers, and moderate pulses of several joules per square centimeter for ablation.

Excimer Lasers have played an important role in high-resolution photolithography, enabling transistor sizes to shrink below 45 nanometers, helping the continued advancement of Moore's Law (that same-size circuit capacity doubles every two years) for the last two decades.