Laser ablation of polymers

Abstract

Recently, there has been increasing interest in direct ablation of materials by short-pulse laser beams. Materials under study vary from thin metal films, metal and semiconductor compounds, and inorganic insulators to polymers, including human hair and photoresists. In this paper, a review of the UV laser ablation of polymers is presented. Srinivasan pioneered in the field of polymer ablation by far-UV (193-nm) pulses. Subsequently, polymer ablation with lasers at a few longer wavelengths has been reported. To date, understanding the etching mechanism and identifying the contributions from photochemical and photothermal activities continue to be the outstanding challenge. The technological issues and the material etching behavior, which varies with laser frequency, fluence, laser pulse length, and material optical absorption, will be discussed for microelectronic applications.

Surface Properties of Polyethylene Terephthalate Films Modified by Far UV Radiation at 193 nm

“…These fibers are present in all types of PET treated, crystalline or amorphous, after exposure to 30 and 50mJ/cm2. The geometry and the structure of the treated surface suggest that the APD products are ejected in a direction perpendicular to the surface at supersonic speed [15,16].…”

A new process for fabricating tip-shaped polymer microstructure array with patterned metallic coatings

“…As reported, photolithography and laser-ablation [20] have been conventionally used to pattern polymer materials. However, except for incline-exposure photolithography [22] which is usually used in SU-8, most structures fabricated by these methods are vertical.…”

“…Thirdly, many polymers have lower melting temperatures than silicon and many thin metal films. Finally, many fabrication techniques for polymer have been established, such as, conventional photolithograph (usually used for polymer precursor photoresist), laser ablation [20], hot embossing [21], thermal micro-molding, soft molding [18], etc. These techniques are widely used to make polymer-based 3D structures which include grid structures for mixing [22], cave structures for locating cells [23], hemisphere structures for focusing lights [24], and so on.…”

Masks for laser ablation technology: New requirements and challenges

“…By irradiating a mask containing the desired pattern and projecting this image onto a material, precise patterns can be produced. This one-step process is therefore capable of replacing conventional multistep processes used in patterning microelectronic structures [4][5][6][7]. The result is fewer manufacturing steps, improved yield, higher product throughput, and lower costs.…”