This IDTechEx report assesses the competing 3D and additive electronics technologies that will enable PCBs to be replaced with integrated electronics, saving space, weight and reducing manufacturing complexity. It covers adding electronic functionality to 3D surfaces, in-mold electronics (IME), and fully 3D printed electronics. Also included are market forecasts, company profiles, readiness level assessments, case studies, and identification of technological challenges/opportunities, thus providing a clear picture of the emerging 3D / additive electronics landscape.
3D electronics is an emerging approach that utilizes additive manufacturing to enable electronics to be integrated within or onto the surface of objects. While it has long been used for adding antennas and simple conductive interconnects to the surface of 3D injection-molded plastic objects, more complex circuits are increasingly being added onto surfaces made from a variety of material by utilizing new techniques. Furthermore, in-mold electronics and 3D printed electronics enable complete circuits to be integrated within an object, offering multiple benefits that include simplified manufacturing and novel form factors. With 3D electronics, adding electronic functionality no longer requires incorporating a rigid, planar PCB into an object then wiring up the relevant switches, sensors, power sources and other external components.
This report from IDTechEx provides an extensive overview of all approaches to 3D additive electronics, informed by interviews with major players in each field. The pros and cons of each approach are weighed against each other for different applications, with numerous case studies showing how the different manufacturing techniques are deployed across the automotive, consumer goods and medical device sectors. Furthermore, through detailed analysis of the technologies and their requirements we identify innovation opportunities for both materials and manufacturing methods.
Electronics applied to a 3D surface
The most established approach to adding electrical functionality onto the surface of 3D objects is laser direct structuring (LDS), in which an additive in the injection molded plastic is selectively activated by a laser. This forms a pattern that is subsequently metallized using electroless plating. LDS saw tremendous growth around a decade ago and is used to manufacture 100s of millions of devices each year, around 75% of which are antennas.
However, despite its high patterning speed and widespread adoption, LDS has some weaknesses that leave space for alternative approaches to surface metallization. Firstly, it is a two-step process that can require sending parts elsewhere for plating, thus risking IP exposure. It has a minimum resolution in mass production of around 75 µm (at present), thus limiting the line density, and can only be employed on molded plastic. Most importantly, LDS only enables a single layer of metallization, thus precluding cross-overs and hence substantially restricting circuit complexity.
Given these limitations, other additive manufacturing methods to applying conductive traces to the surfaces of 3D objects are gaining ground. Extruding conductive paste, a viscous suspension comprising multiple conductive flakes, is already used for a small proportion of antennas, and is the approach of choice for systems that deposit entire circuits onto 3D surfaces.
Aerosol jetting and laser induced forward transfer (LIFT) are other emerging digital deposition technologies, both of which offer higher resolutions and rapid deposition of a wide range of materials. An advantage of digital deposition methods of the incumbent LDS technology is that dielectric materials can also be deposited within the same printing system, thereby enabling multilayer circuits. Insulating and conductive adhesives can also be deposited, enabling SMD components to be mounted onto the surface.
In-mold electronics (IME), in which electronics are printed/mounted prior to thermoforming into a 3D component, facilitates the transition towards greater integration of electronics, especially where capacitive touch sensing and lighting is required. IME enables multiple integrated functionalities to be incorporated into components with thermoformed 3D surfaces. IME offers multiple advantages relative to conventional mechanical switches, including reduction in weight, material consumption of up to 70%, and much simpler assembly.
The IME manufacturing process can be regarded as an extension of the well established in-mold decorating (IMD) process, in which thermoforming plastic with a decorative coating is converted to a 3D component via injection molding. Since IME is an evolution of an existing technique, much of the existing process knowledge and capital equipment can reused.
IME differs from IMD through the initial screen printing of conductive thermoformable inks, followed by deposition of electrically conductive adhesives and the mounting of SMDs (surface mount devices, primarily LEDs at present). More complex multilayer circuits can also be produced by printing dielectric inks to enable crossovers.
Despite the wide range of applications and the advantageous reductions in size, weight and manufacturing complexity, commercial deployment of IME integrated SMD components has thus far been fairly limited. This relatively slow adoption, especially within the primary target market of automotive interiors, is attributed to both the challenges of meeting automotive qualification requirements and the range of less sophisticated alternatives such as applying functional films to thermoformed parts.
The long-term target for IME is to become an established platform technology, much the same as rigid PCBs are today. Once this is achieved getting a component/circuit produced will be a simple matter of sending an electronic design file, rather than the expensive process of consulting with IME specialists that is required at present. Along with greater acceptance of the technology, this will require clear design rules, materials that conform to established standards, and crucially the development of electronic design tools.
Fully printed 3D electronics
The least developed technology is fully 3D printed electronics, which utilizes additive manufacturing of both the dielectric (usually thermoplastics) and conductive materials. Combined with placed SMD components, this results in a circuit, potentially with a complex multilayer structure embedded in a 3D plastic object. The core value proposition is that each object and embedded circuit can be manufactured to a different design without the expense of manufacturing masks and molds each time.
Fully 3D printed electronics are thus well suited to applications where wide range of components need to be manufactured at short notice. Indeed, the US Army are currently trialling a ruggedized 3D printer to make replacement components in forward operating bases. The technology is also promising for applications where a customized shape and even functionality is important, for example medical devices such as hearing aids and prosthetics. The ability of 3D printed electronics to manufacture different components using the same equipment, and the associated decoupling of unit cost and volume, could enable a transition to on-demand manufacturing.
The challenges for fully 3D printed electronics are that manufacturing is fundamentally a much slower process than making parts via injection molding since each layer needs to be deposited sequentially. While the printing process can be accelerated using multiple nozzles, it is best targeted at applications where the customizability offers a tangible advantage. Ensuring reliability is also a challenge since with embedded electronics post-hoc repairs are impossible – one strategy is using image analysis to check each layer and perform any repairs before the next layer is deposited.
Comprehensive analysis and market forecasts
IDTechEx has been researching the emerging printed electronics market for well over a decade, launching our first printed and flexible sensor report back in 2012. Since then, we have stayed close to the technical and market developments, interviewing key players worldwide, attending numerous conferences, delivering multiple consulting projects, and running classes and workshops on the topic.
Our report assesses the 3D/additive electronics market in considerable detail, evaluating the different technologies, potential adoption barriers, and their applicability to different application areas. The report includes multiple company profiles based on interviews with major players across the different technologies. We also develop 10-year market forecasts for each technology and application sector, delineated by both revenue and area. We forecast the gradual decline of LDS and growth in extruded paste for consumer electronic antennas, and increased use of extrusion and aerosol, especially for automotive applications. The most substantial growth is predicted for IME, which we predict will be widely adopted in car interiors and the control panels of white goods.