MicroManufacturing: A Technology Full of Surprises
By Lauralyn McDaniel
Manager, Innovation Watch, MicroManufacturing, Medical Manufacturing Innovations
Micromanufacturing continues to amaze me. As the event manager for SME’s MicroManufacturing Conference, I have worked with professionals in the field for more than 10 years, yet each year, I am surprised at the latest use of micro technologies. What previously was used primarily in medical devices is quickly expanding into other industries.
Have you ever thought about how your camera, tablet or smart phone knows which way to show the screen image? Or how video game controllers know which way you’re moving? Tiny accelerometers do this. Created using micro-machined MEMS, the use of accelerometers is sure to grow as customers increasingly look for products to respond to movement.
Another area has been the focus of much coverage the last few months: 3D printing or additive manufacturing. Stereolithography has long been used to create micro features on polymer components. In 2010, I saw the first use of laser sintering to print micro features in metal. A new 3D microprinting process is faster and finding more applications. Using a two-photon polymerization process, the smallest features are about 30 nanometers. The process uses a tiny, moving mirror to reflect the laser at different angles, greatly increasing the “printing” speed. Micro additive technology/3D printing could be used for making micro needles, heart stents, components for microfluidics and even scaffolds for growing cells and tissue. A team at the Vienna University of Technology has developed special biocompatible materials for the process. Using water-soluble and two-photon active photoinitiators, parts can be fabricated with up to 80% water content creating the possibility of printing living cells and whole organisms.
Combining micro technologies to create new processes or products is another trend. When discussing this first example of combining technologies with a group of micromanufacturing professionals, the general response was “Wow!” Inspired by the fabrication of three-dimensional robotic insects, a method has been created to mass-produce micro-scale devices by the sheet in a fashion similar to pop-up books and origami. Printed Circuit MEMS (PC-MEMS) combines advanced materials and geometries of conventional manufacturing with one-piece construction micro electromechanical systems (MEMS) below the sub-millimeter scale. While insect-scale unmanned aerial vehicles are a direct application, PC-MEMS could be used to create a wide variety of machines and mechanisms. With great advantage at the millimeter to centimeter length scale, the technique applies to a wide variety of advanced materials including exotic metals, carbon and glass composites, plastics, and ceramics.
Another area combining micro technologies is the rapidly evolving field of Neuro Stimulation. Neurologists believe that more effective therapies can be developed by increasing the number of stimulation sites. The goal is to maximize the number of available stimulation electrodes while minimizing the size of the overall power and logic device known as an IPG (Implantable Pulse Generator). Early devices were simplistic with only a couple of connections. Newer devices have reached the size limit of 32 connections with current interconnection technology. By combining micro stamping, micro molding, micro forming and micro assembly, a new device developed by Deringer-Ney has been able to significantly increase the volume of the IPG header. The utilization of micro techniques to incorporate a zero insertion force technology, can double the electrode count without increasing the overall part volume. A cam lobe, micro molded of PEEK, measures just .003” by .005”. An electrical contact, micro stamped of Paliney® Invivo, has features as small as .0015”.
What’s the next trend in micromanufacturing? That will be the topic of the closing panel discussion at SME’s MicroManufacturing Conference and Exhibits (www.sme.org/micro) scheduled for April 16-17, 2013 in Minneapolis. The event features the Medical Manufacturing Innovations Series (www.sme.org/mmi) going beyond micro to discuss critical innovation challenges including improvement strategies, quality and the changing landscape of regulations. You will find more information and meet those involved in all of the micro trends and more in Minneapolis.
I may not be able to predict the next micro trend, but I do know that I will continue to be amazed by future applications.
A version of this article first appeared in MICROmanufacturing magazine on April 5, 2013.