Mechatronic Integrated Devices

Mechatronic integrated devices or moulded interconnect devices, MID for short, are injection-moulded circuit carriers that contain conductive tracks. They are used as nodes for mechatronic or electronic assemblies. 3D mechatronic integrated devices can be moulded into any shape. They are often based on plastic, ceramic or glass. It is possible to integrate thermal, electronic and mechanical functions. Solutions for optical or fluid functions can also be realised. With the help of 3D MID technology, we can expand or combine a standard electronic circuit into an electronic mechatronic assembly.

On the one hand, MID technology is popular due to the savings in materials and moulds for printed circuit boards. The diverse use of materials allows room for customised and environmentally friendly solution concepts. These ensure a reduction in resources and costs.

On the other hand, the high level of flexibility is a major advantage. As MID technology combines mechanics and electronics, it is possible to design components of different types and sizes. The design is almost fully customisable and has electromagnetic compatibility (shielding).

Thanks to the flexible design of individual printed circuit boards, the application of mechatronic integrated devices (MID) extends across various areas. These include, for example:

• Automotive industry
• Medical technology
• Industrial automation
• Telecommunications

MID technology is frequently used in the industry for antennas, lighting and sensors. In medical technology in particular, they are often found as LED lighting elements in illuminants. These can be lighting systems for dental drills, for example. Mechatronic integrated devices also play a role in the consumer goods sector. For example, they are installed in electronic payment systems or headphones. Household appliances also frequently contain MIDs.

Due to the wide range of possible applications, the technology is receiving a great deal of support from public institutions. The research association ‘Räumliche Elektronische Baugruppen 3-D MID’ is a German association that is committed to the promotion and research of MID. It trains and supports small and medium-sized companies in particular with the application of electronic assemblies.

Basically, the term MID stands for the function of the component. Depending on the extension of the designation, the component provides information about the manufacturing method. If a circuit carrier is manufactured three-dimensionally, it is generally referred to as a ‘3D MID’. These are spatial, injection-moulded circuit carriers.

Various processes are used to manufacture mechatronic integrated devices. It is possible to manufacture MID components using two-component injection moulding, hot stamping or film back injection.

The most common method for manufacturing MIDs is laser direct structuring (LDS). A laser beam writes the planned paths of the conductor tracks directly onto the respective component. The technology makes it possible to define the carriers very finely and densely. A metallisation is created on the circuit board, which results in very good bonding between the plastic and the electronics. Another advantage of LDS is that very different thermoplastics can be used. The design is also very flexible. If the conductor path needs to be changed, the control system can be reprogrammed. This results in the efficient development of process chains.