A polyimide foil which is laminated on one or both sides with copper. It is applicable as base material for flexible printed circuit boards.

Applications:

• Semiconductor packaging: BGA, µBGA, TAB, CSP and COF (small circuit feature low profile - high temperature - compatible with high volume processing);
• Medical (small circuit feature - low profile);
• Space (low outgassing - light weight - high temperature);
• Automotive (high temperature - chemical resistance);.
• Portable device - cell phone, PDA, laptop (small circuit feature - light weight - low profile);
• Electronic component - embedded devices, resistors, fuses (low profile - no tiecoat - standard flex circuit processing technologies).

Overview:

FRAFLEX® laminates are adhesiveless, tiecoat-free, copper-clad polyimide films that are manufactured by state-of-the-art vacuum metallization and electroplating processes. Due to an innovative technology, FRAFLEX® micromechanical bonding laminates exhibit exceptional peel strength without the use of a tiecoat between the polyimide film and the copper conductive layer (pict. 1,2). FRAFLEX® laminates also offer excellent mechanical and thermal characteristics. The exceptional property of the FRAFLEX® is that the peel strength of the copper is up to 2,5 N/mm.

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FRAFLEX® laminates are manufactured in a roll-to-roll process with four basic steps. In the first step - ion tracking - polyimide film is irradiated by heavy, high- energy ions. Copper and polyimide are mechanically interlocking connected, all disadvantages of the material, which are caused by the presence of intermediate layers, are completely avoided. Altogether, it is a material which can be fully recycled (“Green PCP”). The thickness of the polyimide foil itself is between 12 and 125 microns. Standard thicknesses of the copper layer are normally 9, 12, 18, 35, or 70 microns.

Features:

• Outstanding peel strength / adhesion;
• Excellent flexural endurance;
• Excellent dimensional stability;
• Thin copper for fine line requirements;
• Excellent heat / thermal resistance;
• Compatible with lead free solder;
• Excellent chemical performance;
• Excellent electrical performance;
• Low moisture absorption;
• Completely recyclable;
• Simple etching (no tiecoat);

BGA- Ball Grid Array.	µBGA -Micro Ball Grid Array
COF- Chip on Flex	TAB-Tape Automated Bonding
CSP- Chip Scale Packaging