Hosted by Alix Paultre, the Tinker’s Toolbox is the Advantage Design Group’s web-based interview show where we talk about the latest technology, components, and design issues for the electronic design engineering community.

In today’s podcast we talk to Richard Macary, President of SelectConnect Technologies, about Laser Direct Structuring. His company, a Division of Arlington Plating Company, manufactures three-dimensional molded interconnect devices (3D-MID) for the military, aerospace, medical device, RF antenna, RFID, sensor, security housing and connector markets. A 3D-MID consists of circuit traces embedded onto molded thermoplastics to form electrical pathways and landings for surface mount components.

Here is a link to the podcast in case the play button is not working: SelectConnect Interview

Here is a recent release from the company:

When the Insulet Corporation, an innovative medical device company, sought to improve the functionality of its OmniPod Insulin Management System, it partnered with Phillips Plastics Corporation to create an optimally performing internal plastic component called the “chassis.” Phillips Plastics injection molded the chassis using two-shot molding and Insulet chose SelectConnect Technologies to provide the metallization, an integral step in completing the 3D Molded Interconnect Device (MID). SelectConnect Technologies utilizes a patented SelectConnect™ process to selectively plate injection molded parts with copper and nickel in order to create three-dimensional connections with multiple points of contact.

The chassis is a critical component of the OmniPod, a small, lightweight, tubing-free insulin pump worn on the skin, which delivers insulin according to instructions transmitted wirelessly from the system’s hand-held Personal Diabetes Manager (PDM). 3D-MID technology enables the chassis to provide mechanical support and electrical connectivity in the device. And, because MIDs require reduced space, they allow for the integration of more electronic functions. The need for multiple different parts that would complicate assembly and increase the size of the device is eliminated.

Phillips determined that two-shot molding would be the best process to manufacture the chassis. The process produces MIDs from a combination of plateable and non-plateable injection molded resins. A non-plateable polymer is molded in the first shot and is then selectively molded with a second plateable material, leaving specified areas exposed. An etching step then activates the exposed areas of plateable polymer so that those areas can be plated with metal.

Once Phillips completed the injection molding, the finished chassis came to SelectConnect Technologies for metallization. Rich Macary, General Manager of SelectConnect Technologies explained, “Our SelectConnect metallization process is unique in that it allows us to control the metal deposition process to produce fine electronic traces with high resolution and yield. Once we receive the molded parts, we then build electroless copper, electroless nickel, and immersion gold traces on the structured patterns to form the circuit path. It allows the circuitry to be incorporated directly onto the plastic component, offering a wide range of innovative design possibilities including the opportunity for miniaturization, parts consolidation, reduced assembly time, and cost reduction.” For the chassis, SelectConnect uses 250 micro inches (6.25 microns) of electroless copper. This thickness is required to get a good conductive path throughout the part. A thin layer [50 micro inches (1.25 microns)] of nickel is then added on top of the copper to create a barrier layer that prevents the copper from oxidizing before the entire assembly is press-fit into a circuit board.

In addition to providing metallization for two-shot molded MIDs, SelectConnect Technologies also does Laser Direct Structuring (LDS) of one-shot injection molded components. The component is molded from a commercially available doped thermoplastic, laser traced to write the circuit-layout onto the component, and then metallized with copper, nickel and gold. The LDS process is ideal for transferring circuit artwork directly onto three-dimensional components.

For more information on the SelectConnect metallization process, contact SelectConnect Technologies at 847-359-1490, or visit www.selectconnecttech.com.