Products & Solutions

3D–MID Process

In our short explanatory video you will get to know the 3D – MID Process.

Materials

Special thermoplastics are required in 3D-MID manufacturing.

In laser direct structuring, metal oxide additives that are activated by the laser energy for the subsequent chemical metallization are embedded in plastic. The metallization takes place only in the laser-structured areas of the component. The LDS process enables the use of numerous plastics that are selected on the basis of economic and technical criteria. High-temperature thermoplastics such as PEEK or LCP, technical materials like PA, PPA or PBT and duroplastic epoxide masses are available for this area.

In 2K technology (two-shot injection molding), special material combinations are employed to manufacture MIDs. A catalyst is compounded into one of the two materials so that the conductor paths can be selectively mapped during the subsequent metallization. For series applications in MID technology, the material combination LCP Vectra® E820i Pd is predominantly chosen as the metallizable component and LCP Vectra® E130i as the non-metallizable component. Further material combinations are possible.

Injection molding

In general, the process sequence in MID technology does not differ from conventional plastics processing. High quality calls for the appropriate preparation of the materials, observance of influences related to the manufacturing and adapted further processing after the injection molding process. The injection molding die is not permitted to exhibit any signs of damage.

The use of separating agents must also be avoided. Impurities on the die surface and in the plastic are not allowed. The injection molded part is not permitted to exhibit any cracks, burrs, bubbles, burn marks, shiny spots, streaks or sink marks. Appropriate precautions must be taken during part removal and assembly transport in order to avoid scraping the components.

Laser direct structuring

In the additive LPKF-LDS® process, the structuring is performed by a laser beam that exposes and activates special additives in the plastic. Here, the infrared laser light forms a microscopically rough surface in the irradiated areas with metal particles and micro-cavities.

The applied laser energy changes these metal particles in such a way that they act as a catalyst in the following metallization step, producing selective metal separation. The roughness allows the conductor paths to achieve the optimal bonding strength.

Metallization

3D-MID metallization is usually handled without an external current by means of an additive conductor path structure, as the thermoplastic materials cannot be directly metalized with a galvanic method due to their isolating properties. The necessary electrons are provided by a metallization bath component and not by an external current source. If special applications require a greater current carrying capacity or special surface properties for the connection method, the chemically applied copper layer can be reinforced later in galvanic procedures.

HARTING AG Mitronics has set up one of the largest and most advanced, leading-edge metallization plants specifically for 3D-MIDs in Biel (Switzerland). In addition to the standard copper-nickel-gold layer system, the plant offers various expansion options for other final surfaces and is coordinated especially to the requirements of the laser direct structuring and two-shot injection molding 3D-MID procedures. Metallization takes place in a barrel or frame, depending on the size and geometry.