NIST Invents Fleet and Fast Test for Nanomanufacturing Quality Control
March 7, 2016 | NISTEstimated reading time: 3 minutes
Manufacturers may soon have a speedy and nondestructive way to test a wide array of materials under real-world conditions, thanks to an advance that researchers at the National Institute of Standards and Technology (NIST) have made in roll-to-roll measurements. Roll-to-roll measurements are typically optical measurements for roll-to-roll manufacturing, any method that uses conveyor belts for continuous processing of items, from tires to nanotechnology components.
In order for new materials such as carbon nanotubes and graphene to play an increasingly important role in electronic devices, high-tech composites and other applications, manufacturers will need quality-control tests to ensure that products have desired characteristics, and lack flaws. Current test procedures often require cutting, scratching or otherwise touching a product, which slows the manufacturing process and can damage or even destroy the sample being tested.
To add to existing testing non-contact methods, NIST physicists Nathan Orloff, Christian Long and Jan Obrzut measured properties of films by passing them through a specially designed metal box known as a microwave cavity. Electromagnetic waves build up inside the cavity at a specific “resonance” frequency determined by the box’s size and shape, similar to how a guitar string vibrates at a specific pitch depending on its length and tension. When an object is placed inside the cavity, the resonance frequency changes in a way that depends on the object’s size, electrical resistance and dielectric constant, a measure of an object’s ability to store energy in an electric field. The frequency change is reminiscent of how shortening or tightening a guitar string makes it resonate at a higher pitch, says Orloff.
The researchers also built an electrical circuit to measure these changes. They first tested their device by running a strip of plastic tape known as polyimide through the cavity, using a roll-to-roll setup resembling high-volume roll-to-roll manufacturing devices used to mass-produce nanomaterials. (See video.) As the tape’s thickness increased and decreased—the researchers made the changes in tape thickness spell “NIST” in Morse code—the cavity’s resonant frequency changed in tandem. So did another parameter called the “quality factor,” which is the ratio of the energy stored in the cavity to the energy lost per frequency cycle. Because polyimide’s electrical properties are well known, a manufacturer could use the cavity measurements to monitor whether tape is coming off the production line at a consistent thickness—and even feeding back information from the measurements to control the thickness.
Alternatively, a manufacturer could use the new method to monitor the electrical properties of a less well-characterized material of known dimensions. Orloff and Long demonstrated this by passing 12- and 15-centimeter-long films of carbon nanotubes deposited on sheets of plastic through the cavity and measuring the films’ electrical resistance. The entire process took “less than a second,” says Orloff. He added that with industry-standard equipment, the measurements could be taken at speeds beyond 10 meters per second, more than enough for many present-day manufacturing operations.
The new method has several advantages for a thin-film manufacturer, says Orloff. One, “You can measure the entire thing, not just a small sample,” he said. Such real-time measurements could be used to tune the manufacturing process without shutting it down, or to discard a faulty batch of product before it gets out the factory door. “This method could significantly boost prospects of not making a faulty batch in the first place,” Long noted.
And because the method is nondestructive, Orloff added, “If a batch passes the test, manufacturers can sell it.”
Films of carbon nanotubes and graphene are just starting to be manufactured in bulk for potential applications such as composite airplane materials, smartphone screens and wearable electronic devices.
Orloff, Long and Obrzut submitted a patent application for this technique in December 2015.
A producer of such materials has already expressed interest in the new method, said Orloff. “They’re really excited about it.” He added that the method is not specific to nanomanufacturing, and with a properly designed cavity, could also help with quality control of many other kinds of products, including tires, pharmaceuticals and even beer.
Suggested Items
Real Time with… IPC APEX EXPO 2024: Tools, Training, and Trends in Manufacturing Engineering
04/25/2024 | Real Time with...IPC APEX EXPOGuest Editor Kelly Dack and Product Specialist Erik Bateham of Polar Instruments discuss Polar's latest technology, including their role in aiding manufacturing engineers. They highlight the advanced capabilities of Polar's tools and the critical role of signal integrity analysis, as well as the importance of accurate modeling in board manufacturing. Polar's unique training approach and demonstration contact details are also explored.
TTM Celebrates the Grand Opening of Its First Manufacturing Facility in Penang
04/25/2024 | TTM Technologies, Inc.TTM Technologies, Inc., a leading global manufacturer of technology solutions including mission systems, radio frequency (RF) components and RF microwave/microelectronic assemblies, and quick-turn and technologically advanced printed circuit boards (PCBs), officially opened its first manufacturing plant in Penang, Malaysia with an investment of USD200 million (approximately RM958 million).
Listen Up! The Intricacies of PCB Drilling Detailed in New Podcast Episode
04/25/2024 | I-Connect007In episode 5 of the podcast series, On the Line With: Designing for Reality, Nolan Johnson and Matt Stevenson continue down the manufacturing process, this time focusing on the post-lamination drilling process for PCBs. Matt and Nolan delve into the intricacies of the PCB drilling process, highlighting the importance of hole quality, drill parameters, and design optimization to ensure smooth manufacturing. The conversation covers topics such as drill bit sizes, aspect ratios, vias, challenges in drilling, and ways to enhance efficiency in the drilling department.
Elevating PCB Design Engineering With IPC Programs
04/24/2024 | Cory Blaylock, IPCIn a monumental stride for the electronics manufacturing industry, IPC has successfully championed the recognition of the PCB Design Engineer as an official occupation by the U.S. Department of Labor (DOL). This pivotal achievement not only underscores the critical role of PCB design engineers within the technology landscape, but also marks the beginning of a transformative journey toward nurturing a robust, skilled workforce ready to propel our industry into the future.
Fujitsu, METRON Collaborate to Drive ESG Success
04/24/2024 | JCN NewswireFujitsu Limited and METRON SAS, a French cleantech company specializing in energy management solutions for industrial decarbonization, today announced a strategic initiative to contribute to the realization of carbon neutrality in the manufacturing industry.