Using of solderable conductive pastes in PCB prototyping

The paper presents some tests in the field of through-hole plating process using special solderable conductive pastes in order to metallize the barrel of drilled holes for vias. The process consists of dispensing the special paste into holes, absorption of paste from them, keeping inside only the necessary quantity for metallization, and curing the paste into a regular hot-air oven at 160/spl deg/C for 30 minutes. The process is appropriate for small/medium quantity of vias (less than 400) and FR4 substrate. The contact resistance, specified by producer as 150 m/spl Omega/, will be analyzed. In addition, pastes shall be evaluated as soldering materials destined for contacting the SMDs onto the printed circuit boards.