초록 |
FOWLP (fan-out wafer level packaging) is a high performance and low cost option for multi-chip module (MCM) or system in package (SiP) technology. This technology provides many advantages such as die and package scaling, increased number of I/O, high throughput, and low cost. In spite of the positive advantages of FOWLP, die shift, warpage issues, and multi-layer RDL process are still the key problems to be resolved. For multi-layer RDL barrier etching, dielectric coating, planarization, etc. are the main process issues, especially for fin pitch RDL structure. In the present study, the effect of laser etching on Ti, Cr, and Ni barrier materials was investigated. The etching characteristic of laser etching process on sputtered barrier/seed layers has been evaluated by measuring electrical resistance, critical dimension of metal line, and undercut of barrier/seed layer. |