A new technology exists at the intersection of additive manufacturing and micro manufacturing. It is opening up the possibility for manufacturers to take advantage of the inherent advantages of AM while achieving micron level accuracy over a build envelope of 5 x 5 x 10 cm.

Jon Donner, CEO, Nanofabrica

There are two current global trends in manufacturing. The first is the trend towards miniaturization, which demands parts and components with highly precise micron and sub-micron level resolution. The other trend is the move towards digital manufacturing referred to as Industry 4.0. Additive Manufacturing (AM) is a key enabling technology catering for the move towards shorter product life cycles, and allowing mass customization.

The low set up costs associated with AM when compared to traditional manufacturing processes explains why a growing number of blue-chip companies across the world are adopting it as a manufacturing technology.

Now, a new technology exists at the intersection of AM and micro manufacturing, opening up the possibility for manufacturers to take advantage of the inherent advantages of AM while achieving micron level accuracy over a build envelope of 5 x 5 x 10 cm.

The discipline of Additive Manufacturing (AM) or 3D Printing (3DP) is regularly cited as being disruptive to traditional manufacturing processes. Indeed there are existing AM production applications across varied vertical sectors that support this position–optimized components and parts that would be either impossible or uneconomic to produce using traditional methodologies that are better made using AM technologies. In this way AM is disruptive and promotes innovation across many industry sectors.

For some OEMs throughout the automotive, aerospace, medical (and other markets), AM has already become an established production process, including some instances of mass manufacturing. However, some barriers to entry for adoption of AM as a production technology still exist, key among these being the requirement for high initial capital investment and expensive on-going running costs; consumable costs (particularly for refined materials); inconsistent material properties which are a significant prohibitor for critical components; extensive pre-and post-processing requirements (and costs); and, often, a failure to understand when and how to apply AM to maximize its benefits.

The final reason is the focus of much attention today. AM has made the shift from a prototyping technology to a true production technology, but many lack the insight about what can really be produced on AM platforms, and the inherent characteristics of the process that add significant advantages when it comes to cost, complexity, and timeliness of manufacture.

The manufacturers of additive platforms are aware of these barriers to adoption, as many — mainly at the high-end of the system spectrum — have been refining and developing their respective processes by adding value propositions pre-, in- and post-process specifically for production applications. The corresponding vernacular that has emerged and is increasing in use across AM marketing campaigns and in-depth conversations about AM for production applications is “end-to-end manufacturing solutions.”

In addition, serious players in the AM sector are seeking out niches that are either under-served, or indeed in some instances completely un-served. One example is the area of micro manufacturing which until recently has had no viable AM technology that can reach the resolutions required.

When viewed from the perspective that across industry there is a shift towards miniaturization, with many applications demanding extremely exacting levels of micron and sub-micron precision on macro and micro parts, there is huge potential for an AM platform that can service this trend. A whole raft of traditional production platforms have developed to cater for this demand, but until recently, the ability for AM to produce such precision at all —let alone at volume production levels — has been impossible.

An AM platform tailored for micro / nano manufacturing

Nanofabrica, founded in 2016, recently developed a micron-level resolution AM platform for this sector. The company produced a technological solution that provides an end-to-end solution bespoke to manufacturers requiring micron and sub-micron levels of resolution and surface finish.

To date, key AM platform developers struggle to get resolution under 50 microns, and the few companies that have strived to provide a micro manufacturing AM solution are either expensive in terms of machine costs and cost per part, or slow, or can only print parts that are restricted in size.

Successful AM platform developers need to focus technological advances on areas that open up innovation and the manufacture of products and components hitherto impossible using AM. It is here that Nanofabrica has identified a series of applications where there is burgeoning market demand, where the only route to market at the moment is through disproportionately expensive or restrictive traditional manufacturing technologies, and where the use of AM can open up significant advances on terms of design and function.

These applications exist in the area of optics, semi-conductors, micro electronics, MEMS, micro fluidics, and life sciences. Products include casing for microelectronics, micro springs, micro actuators and micro sensors, and many medical applications such as micro valves, micro syringes, and micro implantable or surgical devices.

Microfluidics is a good example of how a true micro AM technology can outcompete traditional manufacturing processes. Microfluidic channels are used to move incredibly small volumes of liquid, and many of them incorporate functioning components such as filters and pumps. Traditional micro manufacturing processes such as micro molding hugely limit the freedom of design for such microfluidic channels, and it is almost impossible to manufacture functional substructures in them using such processes.

How the process works

The first breakthrough of Nanofabrica’s technology enables high precision at a cost required for industrial manufacturing. The AM process is based on a Digital Light Processor (DLP) engine. But to achieve repeatable micron levels of resolution, it combines DLP with the use of adaptive optics. This tool in conjunction with an array of sensors, allows for a closed feedback loop.

Nanofabrica tackles precision with software where solutions are easier, more robust, and less expensive. Adaptive optics have been used in other areas of technology, but this is the first time that they have been applied to an AM technology.

This technology can achieve micron resolution over centimeter-sized parts. A number of technologies have been combined. Specifically, the developers has taken adaptive optics and enhanced this imaging unit with technology and know-how used in the semiconductor industry (where the attainment of micron and sub-micron resolutions over many centimeters is routine.) By working at the intersection of semiconductors and AM, the developers were able to build large “macro” parts with intricate micro details. It can also do this at speed by introducing a multi resolution strategy, meaning that the parts where fine details are required are printed relatively slowly, but in the areas where the details aren’t so exacting, the part is printed at a speeds 10 to 100 times faster. This makes the entire printing speed anything from 5 to 100 times faster than other micro AM platforms.

For OEMs requiring small parts, thousands of parts can be printed in a single build, making it a mass manufacturing technology for micro product or component manufacturers.

The multi resolution capability is possible through the use of hardware that enables a trade off between speed and resolution, and software algorithms which prepare the part and printing path by defining and sectioning it into low and high resolution areas, which are then fed into the printer path and machine parameters. Of course there are not only two resolutions but a spectrum of resolutions that allow speed to be optimized while maintaining satisfactory results throughout the part.

The final algorithm family focuses on file preparation, optimizing parameters such as print angle build plate, supports etc…, which ensure a precise, optimized, and reliable print process.

The materials are proprietary but based on the most commonly used industry polymers, which enable high resolution in parts built.

What does this mean for manufacturers

Additive manufacturing in the micro space offers several advantages. AM requires no set up costs. The tooling required for traditional manufacturing processes can have a negative impact on time to market. It can also be uneconomical for small or medium sized production runs. For AM technologies, small and medium sized runs are cost-effective, and indeed it is fair to say that today, represent the sweet spot for the technology.

Add into the mix that AM allows for mass customization, personalization, and the ability to use the same manufacturing platform for prototyping, small batches, and mass manufacturing, which enables multiple possibilities for micro manufacturers.

Nanofabrica
www.nano-fabrica.com

Jon Donner earned his PhD in nano optics in the Romain Quidant Plasmonics group at ICFO Barcelona, Spain. Before his PhD, he earned a double degree at TAU (Tel-Aviv University) in physics and electrical engineering and worked in an electro optics lab.