While photolithography provides high-resolution patterning, it does have notable limitations. Creating a single device requires many steps and several different tools and chemicals. Included in this are specialized equipment and cleanroom facilities, making this technique expensive and inaccessible to many researchers or small-scale applications. Moreover, photolithography is not ideal for producing complex designs or three-dimensional structures. It is a single-layer process and creating multilayer structures or 3D microfluidic systems requires multiple rounds of photolithography, alignment and bonding processes that are time-consuming and prone to alignment errors.

Photolithography is primarily suited for processing semiconductor materials like silicon and glass, and is not ideal for materials that are incompatible with the harsh chemicals and high temperatures used in the process. Subsequently, the demand for more accessible and versatile microfluidic devices has grown, and soft lithography has emerged as a game-changer in the industry.

By combining soft lithography with 3D printing, researchers gain access to rapid prototyping capabilities and the ability to create highly customized, intricate three-dimensional microfluidic devices. This integration opens doors to innovative applications across various scientific disciplines and industries, bringing us one step closer to more accessible and tailored microfluidic solutions at a fraction of the cost of traditional methods.

The journey of fabricating PDMS devices for microfluidic applications has seen significant advancements over recent years. Moving from traditional techniques like photolithography to more cost-effective alternatives like soft lithography, new research is now exploring the integration of 3D printing and how it can fit into existing device fabrication workflows.Canadian-based 3D printer manufacturer and 3D material developer CADworks3D is a leader in this space. Combining groundbreaking 3D printer technology with specialized 3D photopolymer materials, CADworks3D has built a complete and efficient 3D printing solution for fabricating PDMS devices. This includes their ProFluidics 285D DLP printer, and their in-house photopolymer resin, the Master Mold for PDMS Device resin.

“During his tenure, Jeff has overseen tremendous growth, including diversifying our customer base, securing our place in the medical market and establishing Mack as a true, vertically-integrated manufacturing partner,” Kendall noted. “Over 36 years he has built a strong organization, and we appreciate his commitment to guiding Josh as he prepares to build on this legacy.”

“As a strategic leader with more than 20 years of experience in sales and marketing focused on market share expansion and revenue growth in medical contract and OEM manufacturing, Josh is an excellent fit for Mack’s business objectives,” Kendall said. “On top of that, Josh’s collaborative approach to managing internal and external stakeholders, along with his strong work ethic, make him an excellent cultural fit to the benefit of our employees and customers.”

3D printing enables the rapid prototyping of microfluidic device designs. It allows researchers to quickly iterate and modify their designs by 3D printing new master molds within one working day, reducing the time and costs associated with traditional mold fabrication. Microfluidic devices become highly customizable where researchers can easily create bespoke microstructures and adapt them as needed to meet specific application requirements.

Prior to Mack, Pang was Chief Commercial Officer at Orchid Orthopedic Solutions, leading commercial activities for the $400 million orthopedic medical device design and manufacturing services provider. He also previously was a distributor principal for CONMED Linvatec Orthopedics and MTF Biologics, directing its Ohio and western Pennsylvania sales team before being promoted to vice president of orthopedic sales. Additionally, Pang built business development and operations experience with Smith & Nephew Endoscopy, Pfizer Pharmaceuticals and Johnson & Johnson. He has a bachelor of engineering degree from Michigan State University, as well as a master of business administration degree from the University of Michigan Ross School of Business.

The early days of microfluidic research saw photolithography as the go-to technique for creating microstructures and patterns on microfluidic devices. It involved the use of photomasks, cleanroom facilities and intricate chemical processes to create precise patterns on substrates like silicon wafers or glass slides.

Vermont Business Magazine Mack Molding, a leading custom plastic injection molder and supplier of contract manufacturing services, announced Tuesday that Josh Pang has been appointed Northern Division President. Pang will succeed Mack Molding President Jeff Somple when he retires later this year.

CADwork3D has developed a 3D printing solution tailored to the fabrication of PDMS devices. Researchers are given the ability to 3D print, clean and cure a master mold in just a few hours, and within one working day a PDMS device can be casted and ready for bonding to a substrate.The ProFluidics 285D is CADworks3D’s flagship DLP 3D printer. While most 3D printers available on the market are repurposed from other industries, the ProFluidics 285D was designed specifically for microfluidics applications. It operates with a unique technology, known as the dynamic pixel advantage. This allows users to print microfluidic devices with superior 3D printed features, and 3D printed devices closely resemble the intended design as shown on the original CAD file. When compared to other 3D printing platforms, the ProFluidics 285D demonstrates smoother surface finishes and properly resolved curves to produce intricate three-dimensional micro features such as serpentine channels, micro wells and domes.

Mack Molding is a leading custom plastics molder and supplier of contract manufacturing services. Mack specializes in plastics design, prototyping, molding, sheet metal fabrication, full-service machining and medical device manufacturing. Founded in 1920, Mack is a privately-owned business that operates 11 facilities throughout the world. Will Kendall is President and CEO. For more information, go to www.mack.com.

The integration of 3D printing into the soft lithography workflow represents the next step in the evolution of microfluidic device fabrication.

Soft lithography was developed as an alternative to photolithography, addressing many of its predecessor’s limitations particularly in terms of cost, simplicity and material compatibility. It refers to a group of techniques that use elastomeric materials in the fabrication of microfluidic devices, with polydimethylsiloxane (PDMS) being the most prevalent. With it, researchers could now prototype and fabricate microfluidic devices more quickly and efficiently.

According to Kendall, Somple will work closely with Josh to transfer his expertise in Mack’s operations, customers and culture over the coming months.

Soft lithography starts with the creation of a master mold, oftentimes using photolithography. This master mold contains a negative relief of the desired microfluidic features such as channels and chambers. PDMS is then mixed, poured onto the master mold, and cured to create a replica of the master mold. This replica is peeled off the master mold and bonded to a substrate through oxygen plasma treatment or chemical bonding to create a sealed microfluidic device. Its greatest advantage is the ability to produce multiple microfluidics PDMS devices from just one master mold in a short period of time.

When used in conjunction with CADworks3D’s Master Mold for PDMS Device Resin, users are able to build master molds with 50µm open channels and surface roughness value (Ra) of 0.18µm. This photopolymer has been formulated to reduce the amount of steps required to fabricate microfluidic PDMS devices. It does not require release agents, coatings or other pre-treatment processes for a successful PDMS cast. 3D printed master molds are able to withstand the temperatures needed to properly cure the PDMS. According to statistics provided by the Kelley Lab from the University of Toronto, with proper care, one 3D printed master mold can be used to create well over 500 PDMS devices. Additionally, 3D printed master molds do not leech any chemicals, allowing casted PDMS devices to retain their biocompatible properties.

Photolithography is the most common master mold fabrication technique. However, as discussed, the photolithography process is expensive, time-consuming and leaves much to be desired in building (a) complex designs and (b) three-dimensional features – all in a timely manner. 3D printing addresses these challenges by offering a new, efficient method to creating master molds.

As President of Mack Molding’s Northern Division, Pang will be responsible for the Company’s four Vermont facilities, as well as Mack Prototype, a prototyping and low-volume manufacturing facility in Massachusetts, and Synectic Product Development, an engineering services group in Connecticut. Mack Molding is part of Mack Group, which includes global provider of complex electronic manufacturing services, Mack Technologies, and is led by President and CEO Will Kendall. Pang will be reporting to Kendall, along with Mack Molding Southern Division President Bryan Campbell.

3D Printing Industry is collective work of several authors in our editorial team. Our dedicated team of writers all have a background in technology and are keen to provide news, views and insight into the latest trends in 3D printing across the board including the pioneering home users, the maker community and industrialists.

Subscribe to the 3D Printing Industry newsletter to keep up to date with the latest 3D printing news. You can also follow us on Twitter, like our  Facebook page, and subscribe to the 3D Printing Industry Youtube channel to access more exclusive content.Are you interested in working in the additive manufacturing industry? Visit 3D Printing Jobs to view a selection of available roles and kickstart your career.Featured image shows a peeled PDMS device fabricated with CADworks3D’s 3D printed master mold. Photo via CADworks3D.

“There is something very special about Mack,” Pang said. “The legacy established by the Kendall family 104 years ago is as strong as ever thanks to their continued leadership and their coworkers’ commitment to running a true customer-centric business. From the way Mack develops its team members to its investments in the community, there is a clear devotion to the foundation of the business. A lot of organizations espouse these ideals, but Mack’s application of them is second to none, and I look forward to carrying on that tradition while fostering continued growth.”

Pang is excited to be joining the organization, noting Mack’s expertise in custom plastic injection molding and contract manufacturing, as well as its reputation for recruiting and retaining top talent, attracted him to the role.