Packaging (Back end Process)
Lithography refers to the patterning or shaping of deposited materials
Whether applying a positive or negative tone in conventional lithography, the wafer is coated with a chemical called photoresist; then, a machine called a stepper focuses, aligns, and moves a mask, exposing select portions of the wafer below to short wavelength light; the exposed or unexposed regions are washed away by a developer solution. After plating, etching or other processing, the remaining photoresist is removed by removers or plasma ashing. Here, we supply resist materials, developers, removers, rinses and chemical enhancements to create the thin circuitry in over forty (40) layers of circuitry.