Four-layer-PCBS

4-LAYER PCBS:

• Assembly: Core made of 1 mm-FR4, on both sides copper plated 18/18 µm or 35/35 µm. Inner layers IN1 and IN2 are etched. Then both sides are laminated with prepreg 20 µm and with copper foils 18/18 µm or 35/35 µm. Afterwards the top and bottom layers are placed. Resulting board thickness is 1.5 mm.
• Different thicknesses of the core and prepreg can be ordered. To achieve proper impedance of the circuit, copper to copper distances can be held in tolerance of 10 µm.
• Drilling according to the drilling data, holes metallized. Blind- or inside-vias can be ordered.
• Solder mask, photolitografically transfered
• Service print
• Tinned with Galvanic gilding HAL /not recommended/, or
• Galvanic gold over galvanic nickel, or
• treated with OSP

Maximum size:

• 380 x 400mm in galvanic tin
• 300 x 400mm solder mask and HAL /not recommended/
• 300 x 400mm galvanic gilded
• 300 x 400mm OSP

Needed documents:

• GERBER data with control prints.Layer order must be clearly marked and described fom TOP to BOT in order not to be interchanged.
• Positive films with tracks, solder masks and service print. Set of data files always required for production purpses.
• EXCELLON drill data. Blind- or inside-vias must be included in separate drill data files. with the information of which layers it concerns.
• Final board size, eventual milling drawing. The final dimensions are finished only by milling. Other wishes have to be consulted during placing the order.
• All multilayer boards are tested: inner layers are optically tested, final boards are electrically tested. This testing is included in the board price.