Eight materials' producers are supplying compounds for a new laser system that substantially improves the economics of molded interconnect devices.
Three-dimensional moldings that integrate electronics made a splashy debut 25 years ago because of their potential to replace conventional circuit boards. High tooling costs for the two-component systems, however, kept their adoption to a bare minimum until very recently.
The most promising new development is a process called laser direct structuring in which a laser creates a circuit on a molded part by activating specially formulated additives in the plastic developed by LPKF Laser & Electronics North America of Wilsonville, OR. Following activation, the paths are coated with copper, nickel and/or gold conductive tracks in electroless melting baths. No etching chemicals are used.
Sales of the systems doubled last year with about half of the applications coming from telecommunications, 20 percent in automotive and 15 percent in medical. "Besides integrated antennas for cell phones and other portable devices, more and more electro-mechanical components are integrating circuitry and mechanical function," Nils Heininger, vice president of MID equipment at LPKF, told Design News. Key users in the U.S. include Molex and Tyco.
In the past 12 months, major materials' companies have begun to announce development of specialized compounds suited for the process.
Lanxess, for example, developed a blend of PET- and PBT-type polyesters with a heat deflection temperature of 482F, allowing the material to cope with the temperatures encountered in reflow and vapor phase soldering. Harting Mitronics is using the new material and process to expand the detection range of its radio frequency identification (RFID) transponders through incorporation of a three-dimensional directional antenna into the component. As a result, the transponders can be read from a range of up to 5m, unlike conventional radio tags that are based on plastic film, also called smart labels.
"Consequently, our RFID transponders can also be attached to metal and liquid containers or integrated into demanding production processes. We therefore see enormous opportunities in logistics, in the internal tracking of production goods, in process control and in spare parts management," says Jorg Hehlgans, head of marketing and sales at Harting Mitronics.
|Integrated electronics expand the range of RFID devices.|