OSPThe OSP method is very quick and cheap. The areas which should be soldered are micro-etched at first. This enlarges the copper surface. During the soldering the OSP coating is dissolved into the flux. The soldering covers pure copper without other metals. Intermetalic solder areas are eliminated. The PPT Co.Ltd. Trencianska Tepla http://web.stonline.sk/ppt/ built for us the horizontal coating line consisting of an ultrasound cleaner, microetching modul, cleaning modul, OSP-bath MEC SEAL 5018 , washing and drying modul. See http://web.stonline.sk/ppt. The ML-PCBs can be coated as well but they are only twice solderable. Passing the solder wave the OSP coating gets thin. The soldering in the next pass must follow very soon. The OSP is suitable for ML-PCBs with the track/insulation ratio 0,2/0,2 mm. The galvanic Au surface prevents the existence of micro-short circuits and the pads are quite flat. OSP is no new method and it is generally well known. It is cheaper than HAL as well. Try what will best meet your demands. |