Challenging demands accompanied by increasing device densities and extension of frequency bands mean that flexible approaches are needed to functionalize existing installation space for high-frequency applications. Molded Interconnect Device technology represents a solution that allows electrical structures, such as antennas, to be applied to nearly any surface.
As frequency increases, so do the demands on antenna components. In cooperation with the Institute of High Frequency Technology and Radio Systems (Institut für Hochfrequenztechnik und Funksysteme, HFT) at Leibniz University of Hannover, the PKF LDS technique is currently being scrutinized for its suitability for next-generation wireless applications.
HFT uses Laser Direct Structuring (LDS) technology in their development work. With LDS, a laser beam structures a three-dimensional part made of an LDS-doped plastic. This laser beam transfers the desired circuit layout onto the substrate while activating the additive at the same time. In a subsequent electroless metallization step, copper layers are built up on the structures traversed by the laser beam. These layers can then be given various surface finishes.
This technology is already established as a preferred manufacturing technique for three-dimensional antennas in the consumer goods sector. LDS antennas covering the frequency band up to 6 GHz, e.g., for Bluetooth, LTE, or Wi-Fi, can be found in many of today’s smartphones, tablets, and wearable devices. The higher the transmission frequency, the shorter the wavelength - and the greater the demands on the components. The question as to the relevant manufacturing criteria for RF applications beyond 6 GHz formed the basis for the cooperation between HFT and LPKF.
Because next-generation wireless systems for consumer electronics and smart homes are also expected to see an extension of the operating frequency bands to include higher frequencies, one focus of the cooperation is on evaluation and optimization of LDS production for applications in the millimeter-wave frequency band, e.g., for 5G communications technologies. The first prototypes of an antenna for use in millimeter-wave sensors operating at 24 GHz were produced at HFT and measurements verified its success. Production of test antennas operating at 77 GHz is currently underway. The results of the test measurements are also extremely promising for these applications and demonstrate the potential for LDS-based antennas operating at higher frequencies.
