Nr 1 - ITME

J. Borecki, J. Felba, A. Wymysłowski
PL ISSN 0209-0058 MATERIAŁY ELEKTRONICZNE T. 37 - 2009 NR 1
ANALYSIS OF BLIND MICROVIAS FORMING PROCESS
IN MULTILAYER PRINTED CIRCUIT BOARDS *
Janusz Borecki 1) , Jan Felba 2) , Artur Wymysłowski 2)
The paper is focused on application of experiment design technique, called Taguchi
method, and application of multi-criteria analysis, in blind microvias forming process
in multilayer Printed Circuit Boards (PCBs). In the paper the results of investigations
of microvia laser drilling are presented. The use of multi-criteria analysis is a helpful
tool which should lead to manufacture microvias with aspect ratio (relation of via deep
to via diameter) higher than 1, and diameter of via in the range of 25 to 350 µm. Finally,
it is possible to manufacture blind microvias with aspect ratio about 6.5.
Keywords: microvia laser drilling, Taguchi method, PCB
1. INTRODUCTION
The growing user demands on miniaturized and more functional electronic equipment
are layout the direction of electronic industry development. The best way
to achieve the higher level of miniaturization is growing interconnections density
in PCBs. It is possible by the reducing the area occupied by single interconnection.
Helpful in this aspect is the use of microvia technique.
1)
Tele and Radio Research Institute, Centre of Advanced Technology, ul. Ratuszowa 11,
03-450 Warszawa, Poland; e-mail: janusz.borecki@itr.org.pl
2)
Wroclaw University of Technology, Faculty of Microsystem Electronics and Photonics,
ul. Janiszewskiego 11/17, 50-372 Wroclaw, Poland
*
Praca prezentowana na XXXII International Conference of IMAPS - CPMP IEEE,
Poland, Pułtusk, 21-24.09.2008
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