The LIM-3D is a stackable multi-layer circuit construction which can be applied on any 3D substrate surface, including irregularly-shaped electronic devices, based on laser-induced metallization. In fact, LIM-3D is one important step ahead of the current comparable technologies which are either limited to a flat construction as in multi-layer printed circuit boards (PCB) or confined within one single layer of three-dimensionally extending circuitry.

“In one sense, LIM-3D is analogous to multi-layer PCB as both allow multiple stacking of individual circuitry layers. However, an important and advantageous difference of LIM-3D is that it is compatible with any non-flat shape and provides 3D circuitry for circuit components of electronic devices that need to be assembled in a non-planar, three-dimensional space. In contrast to PCBs, the LIM-3D technique has copper traces formed by an additive method via deposition of copper on the pattern of the circuitry.” said Huang Meng-chi, Manager at Advanced Packaging Technology Department of ITRI.

The LIM-3D process is simple, with just three major steps. First, the LIM-3D’s laser-induced catalyst-containing material is deployed to the structural surface of the target object in which 3D circuitry construction is desired. Then, copper deposition-activating catalyst is revealed through laser burning. Lastly, electrically conductive copper traces are formed via an immersed chemical deposition procedure.

LIM-3D is also capable of stacking multiple layers of irregular 3D circuitry instead of just a single layer. This increases density and allows complex circuitry for high-performance miniature electronic devices requiring more sophisticated circuitries. Furthermore, LIM-3D is compatible with a wide range of substrate materials, allowing greater flexibility for 3D circuit construction. Materials include PC (polycarbonate), ABS, PET, COC (cycloolefin copolymer), LCP (Liquid Crystal Polymer), ceramics, metals and flexible films. Even Teflon is applicable, although with reduced binding capability. In addition, the process can be conducted at as low as 60 degrees, a temperature compatible with the category of ferrite substrates that can not resist high temperature.

ITRI has applied this 3D patterning technology to design and construct high-performance antennas for smartphones. These antennas can be produced using traces as fine as 30 micrometers, which supports antennas with frequencies from microwave frequencies up to mm-wave frequencies. ITRI has allied with manufacturers to accelerate the widespread production and commercial application of this technology, targeting the potential markets of 3D laser equipment and 3D circuit manufacturing.

LIM-3D can provide many benefits such as improving circuitry density and performance while reducing device size, all at a lower cost as it does not require expensive materials or production procedures. This technology essentially elevates our current 3D circuitry technology that will make a major contribution to Internet of Things, high-speed applications and 5G communications.