High Density Interconnections Fabrication by UV Lasers Microprocessing of Microvias and Microstructures

D. Ulieru (a), Alina Matei (b), Elena Ulieru (c), A. Tantau (c), Florin Babarada (d)

(a) ROMES S.A., 126A, Iancu Nicolae Str., Bucharest, 72996, ROMANIA
(b) National Institute for Research and Development in Microtechnologies, 32B,Erou Iancu Nicolae Str., Bucharest, 077190, ROMANIA
(c) SITEX 45 SRL, 114, Ghica Tei Blvd., bl. 40, ap. 2, Dept. 2, Bucharest 72235, ROMANIA
(d) “Politehnica” University of Bucharest, Splaiul Independentei Str., No. 313, Bucharest 060042, ROMANIA

Abstract

The strong evolution of electronic packaging in the field of high performance hand held electronic products involves, from the fabrication point of view, to manufacture small, lightweight, reliable and, very important too, cost effective electronic modules. In the last years new techniques and technologies for production of rigid/flexible MCMtype multilayer were introduced. The manufacturers of laminate substrates are being challenged to realize boards with very good electrical and mechanical properties. In the past the biggest issues regarding vias and via capture pad sizes were only solderability and manufacturability. Today the vias density is also an important electrical issue. The more vias on a board are presented, the more discontinuities into PCB/MCM passive interconnection structure are placed. For High Density Interconnection (HDI) circuits design one solution is to reduce the via hole and the via capture pad, but still maintain manufacturability at board fabrication stage.The most indicated solution is to use UV laser microprocessing for HDI production.