About a month ago I posted about the various 3D technologies (chip creation, packaging and printed circuit boards) that are being used to optimize the various electronics upon which we all rely. Molded Interconnect Device (MID) technology has been around for more than 20 years and is being used extensively in cell phone antennae.
Recently I discussed the state of the art of 3D-MID technology with the Director of 3D MID Technology at Cicor in Switzerland, Nouhad Bachnak. Cicor is one of the key players in the development of molded interconnect devices.
Carol: MID technology has been around for more than 20 years but, so far, it is only widely adopted in cell phone antennae. What is sparking the renewed interest for other electronic applications?
Nouhad: The idea to use 3D-MID for electronic applications is much older than the idea to use this technology for antenna applications. When this technology started in the 1980's there was a high euphoria that it would replace the printed circuit board (PCB). But there was a lack of qualified materials and a lack of specific know-how for the manufacturing process.
Over the last few years a tremendous amount of development work has been done and considerable progress was made.
New MID-specific design, chemical and 3D assembly machines were developed and successfully implemented in serial production. Millions of antennae have been produced, but also several other products like sensors, switches and LED carriers for automotive, medical and industrial applications show the benefits of 3D-MID and this encouraged customers to use them.
Carol: What processes do you offer for making these devices and what are the benefits of each?
Nouhad: We use the LPKF Laser Direct Structuring (LDS) and the 2S (two shot molding) processes. These two processes have to be seen as complementary to each other, rather than competing with each other.
Major advantages of the LDS process are:
- Simple injection molding tool
- Easy layout changes (just by changing the CAD layout)
- Thin structures are possible 150 µm or even smaller
Major advantages of the 2S process are:
- Only two process steps for the substrate manufacturing (molding and plating)
- High reproducibility of the layouts
- Very economical for big plating surfaces and complex layouts
Carol: What are the biggest challenges facing component attachment to 3D-MID?
Nouhad: The first one is the 3D attachment of the components on the MID substrate. Precise 3D electronic assembly systems with several axes and sophisticated optical systems are required to master this task accordingly. In this area we are working with Haecker Automation, who develops such high-standing quality systems. The other aspect is the capabilities of the substrates to withstand high temperature solder profiles. There are of course several materials which can withstand up to 260C. But these materials usually have some other weaknesses (fragile, too expensive).
Carol: What markets are showing the most interest in using this technology to replace traditional printed circuit boards?
Nouhad: Using the benefits of 3D-MID is not limited to certain markets. 3D-MID can be used everywhere, where plastics meets electronics and it is not just about replacing PCB. 3D-MID opens a tremendous amount of possibilities by using MID as an interconnectivity module combining electrical and mechanical functions in one part.
Carol: What do you see as the key drivers in moving MID forward in the electronics industry?
Nouhad: The key drivers in moving 3D-MID forward are:
- Miniaturization: due to space problems (automotive, medical, telecommunication, etc.)
- Rationalization and system simplification: reduction of process steps, number of parts and mounting time
- Functionality: new functions which are made possible only because of the high functional integration possibilities, design flexibility and the precision given by 3D-MID
The 3D-MID technology advantages in these areas are:
- Optimal three dimensional space utilization
- High function integration density of mechanical and electronic functions
- Saving of parts and process steps
Carol: Where do you see the industry in another ten years?
Nouhad: This is the most difficult question! In this context I would like to quote the famous physicist Nils Bohr: "Forecasts are always difficult-especially if they concern the future".
Nevertheless one thing seems to be evident: the 3D-MID technology has already gained a footing in the market and is growing very fast. For our part, for the next three years, Cicor is planning its manufacturing capacities according to growth rate expectation of more than 50% per year.
Thanks Nouhad for your time and expertise.
Like we have often said about indium metal, the possibilities are endless®!