About laser
LASER stands for Light Amplification by Stimulated Emission of Radiation. We offer laser fabrication processing service using short wavelength and short pulse laser specialized for microfabrication. Here, we will briefly explain the features of short wavelength laser and short pulse laser which are suitable for microfabrication what we are good at.
Laser features
Compared with ordinary light such as sunlight, the laser has following features.
1.Excellent directivity : Laser light has high rectilinearity and advances almost straight.
2.Excellent in monochromaticity : It is light of pure single color (wavelength).
3.Excellent coherence : The phases of light (crest and trough) are aligned.
About short wavelength laser
What is a short wavelength laser?
Lasers with wavelengths in the ultraviolet region are called short wavelength lasers. A representative thing is the KrF excimer laser. Because the wavelength is λ = 248nm, it is possible to process by ablation (the surface of the material is decomposed / scattered by evaporation / erosion) process rather than the heat scattering process.
Ablation process
1.Short wavelength laser light irradiated on the workpiece is efficiently absorbed in the very shallow region of the surface layer of the workpiece. The irradiation light can be made into various shapes by mask.
2.The intermolecular bond is broken at the part where laser light is absorbed, and the volume expands. The absorbed depth can be controlled by the pulse number of the laser.
3.The workpiece whose volume has expanded will lose its location and scatter into the atmosphere. Scattered waste is collected by a dust collector.
About short pulse laser
What is a short pulse laser?
Although there are lasers of various wavelength, it is a genetic name of lasers with pulse width of picoseconds to femtoseconds. One picosecond (1 ps) is one trillionth of a second, and one femtosecond (1 fs) is one thousandth of a second, which is a very short time. Since one pulse of irradiation finishes at the extremely short time, the heat effect given to the materials is minimal.
We can handle both processing picosecond laser and femtosecond laser.
About the name of laser
When calling a laser, it is called a xx laser, but xx is a wavelength (color), oscillation medium, pulse width, various kinds of words are entered.
The name will be explained here.
In case of wavelength (color)
Infrared (IR) laser, green laser, ultraviolet (UV) laser etc.
It is a way to classify by the color of laser light.
In case of oscillating medium
Gas laser, solid (crystal) laser, semiconductor laser, liquid laser, fiber laser. It is a nomenclature to classify by the medium that receives the excitation light source. More finely, KrF excimer laser, CO2 laser etc. Kind of gas, YAG laser, YVO4 laser etc. It often called with crystal type.
In case of oscillation method
Two kinds of name, pulsed laser or CW laser.
It is a way to classify by pulse oscillation or continuous oscillation.
In case of pulse width
In case of pulse oscillation, it may be classified more finely.
For example, microsecond laser, nanosecond laser, picosecond laser, femtosecond laser etc. It is classification by pulse width of the laser.
As a major classification, it is mainly divided into the above four types, but it is natural that it is a picosecond laser which is solid with ultraviolet rays, there are CW lasers etc. gas laser with infrared rays.
For people who are unfamiliar with lasers, it will be a source of confusion, but currently there are no clear classification indicators.
As we specializes in fine and nonthermal processing, we mainly have lineup with infrared to ultraviolet laser, pulsed laser, picosecond laser, femtosecond laser as classification.
