Combined Thick Resist Processing and Topography Patterning for Advanced Metal Plating

Photoresist coating and patterning are the most repeated process steps in advanced packaging. Spin coating is still the prevalent method of coating planar surfaces and the patterning of thin films. However thick resist processing [1] and spray coating [2] are nowadays well established and commonly used for advanced patterning requirements. Thick resist processing is widely used for plating of interconnects [3] or LIGA fabrication. Spray coating is mainly used to efficiently protect or pattern severe topography and an essential process for packaging, plasma dicing, and MEMS.