Manufacturing Precision Flexible Heaters with Laser Direct Imaging

At Birk Manufacturing, our customers require the highest quality flexible heaters and heating solutions. We work with mission critical applications in aerospace and defense, life-saving applications in medical devices, and high-tech applications in semiconductor manufacturing. Precision, consistency, and turnaround time are critical. That’s why Birk continuously invests in new technology that supports our customers’ needs. 

Over the summer, our team was thrilled to start using Laser Direct Imaging (LDI), an incredible innovation in flexible heater manufacturing with benefits our customers will value allowing us to manufacture precision flexible heaters with speed and accuracy.

What is LDI and How Does it Work?

At its core, Laser Direct Imaging (LDI) is an advanced method of transferring circuit patterns onto flexible heater panels. Birk’s traditional method uses a multistep process where an engineer’s circuit design or ‘artwork’ is printed onto a transparent sheet, developed, and then layered over a panel consisting of substrate, metal foil, and dry film for UV-light processing. The UV light causes the dry film to harden over transparent areas of the artwork, creating a protective layer over the metal foil. The “soft” areas are removed, leaving behind the metal foil circuit design.

With LDI, most of these steps are eliminated from the process. The circuit design file is loaded directly into the LDI machine which laser prints the design onto the panel. The panel is made of a substrate, metal foil, and the same UV-sensitive dry film, but instead of exposing it through a physical mask, the laser directly hardens only the areas needed for the final circuit design (similar to the UV processing step above).

This method eliminates printing, developing, and aligning the design sheet on the panel, making it significantly faster.

Benefits to our Customers

By adopting LDI technology, Birk offers substantial advantages to its customers:

• Faster Production: The LDI reduces production time thanks to the elimination of several steps in the process.
• Rapid Prototyping: Design updates can be made digitally and sent directly to the machine.
• Outstanding Precision: The laser excels at fine-line circuitry. It can achieve line weights and spacing down to 0.002”, consistently, whereas the traditional method is .010”. The LDI can also produce consistent circuit edges with a +/- 2 micron edge roughness. Using traditional methods, circuit edges are limited to 3200 DPI, a far less accurate measure than the LDI.
• Repeatability and Consistency: LDI’s accuracy ensures high yields and consistent results across multiple production runs.

Meeting NASA Standards with Confidence

One standout use case involved a project requiring compliance with NASA’s strict standards, including minimum spacing and linewidths. With traditional UV methods, hitting those tight specs is more labor and time intensive. LDI enables Birk to meet these critical tolerances consistently and quickly.

Supporting Copper and Gold Plating Processes

LDI also plays a vital role in mask alignment for plating. When heaters require copper or gold plating in specific areas, the LDI system uses etched pinholes for exact alignment of plating masks. This improvement replaced a more labor-intensive manual process, dramatically increasing accuracy and repeatability.

A Win for Customers and the Birk Team

For customers, LDI means Birk can manufacture precision flexible heaters with faster delivery, increased product reliability, and confidence that even the most demanding specifications can be met. For Birk’s engineering and production teams, it means streamlined workflows, reduced errors, and the ability to take on more complex, high-precision projects without sacrificing turnaround time.

Laser Direct Imaging is more than just a technological upgrade, it’s complete alignment with Birk’s mission to be the leader in designing and manufacturing high quality, custom engineered heating elements, temperature management devices, and complete thermal assemblies.

Reach out to find out how Birk’s can support your projects.