Understanding photoresist - electroplating bath interactions using HPLC methodology

Abstract With the rapidly expanding range of design and integration flows required for advanced packaging, both foundries OSATs alike are evaluating new types materials additive manufacturing - this is especially pertinent resist galvanic plating baths. This problem far from (1), it a part regularly re-evaluation process-material interactions (2) packaging schemes, driven by changes in design, process flow, technology requirements. increasing demands bath longevity robustness performance, material vendors motivated to minimize between chemistries photoresists, defining pattern. In study, we have evaluated effect several factors including type (i.e. positive, negative, general-purpose vs “plating/packaging” type) parameters (by comparing different manufacturers with varying processing conditions on silicon wafers). We used reverse phase HPLC UV-detection as method choice study compare extractables into utilized copper representative material. semi-quantitatively extractable via their signature properties further attempt extrapolate stability breakdown magnitude possible effects life. The utility developed here allows quantifying (note evaluation semi-quantitative since no standard solutions leached components exist) (high-performance liquid chromatography) better understanding “factors”, can be expanded an online detecting early signs contamination photoresist. It also aiding lithographers pre-assess photoresist capabilities aid selection future applications.