Circuits’ 30,000 sq. ft. facility was designed specifically for flex and rigid-flex manufacturing. Download the equipment list or take the virtual tour.
Unfortunately, PCB fabrication has a reputation for being a dirty business, and probably for good reason. There are still plenty of fab houses out there where your nose is assaulted upon entering the building and your feet most likely stick to the floor during the plant tour.
At Circuits, we believe that clean manufacturing is not only ecologically responsible, but it can also improve board quality and reduce overall costs. The manufacture of flexible printed circuits is particularly sensitive to adverse environments, excessive handling, and in-process contaminants necessitating the need for cleaner manufacturing principles.
Our manufacturing operation was designed as an open space to enable better communication and efficient flow of materials. In a factory that uses water at a rate of 10-15 gallons per minute and uses chemical processes to produce product, the factory design required careful planning and consideration to create an environmentally friendly setting. These factors drove a factory-wide initiative at Circuits, resulting in the use of solar energy in the plating processes to the proper handling of air, water and waste from the facility.
Circuits’ uses a solar heating process that directly utilizes clean renewable solar energy. The energy is used to heat water through a heat exchanger for the plating process rinses and the ENIG line which has a direct effect on the quality of the finished product. The most common defect found in flexible printed circuits is plating cracks. These cracks are a typically a result of organic contamination in the plating process. The best way to eliminate these organics is by reducing any chemical or residue bleed from one bath to the next. Reducing the residue is best accomplished with warm water rinsing. The eight roof top panels directly above the manufacturing floor at Circuits heat 10 gallons water per minute to 70°F with as little as 3 ½ hours average sunlight per day, providing the facility with ample warm process water at a fraction of the costs associated with gas and electrical consumption.
Our open floor plan required Circuits’ to take special care in the planning of air handling, reducing fumes and dust particles were crucial to the design. The air conditioned facility is equipped with an advanced exhaust system including a fume scrubber to reduce fumes in the manufacturing area and any pollutants leaving the building. The self-contained clean room central to the operation utilizes an independent air conditioning and HEPA air filtration system providing the safeguards needed to prevent particle contamination during the imaging processes.
Critical decisions made when designing both an open and environmentally friendly business were rooted in the chemical processes used in PCB fabrication. We ultimately chose processes that are proven to yield a better quality finished product without sacrificing the principles our clean manufacturing philosophy.
Plating Finishes: When the RoHS directive took effect on July 1, 2006 restricting the use of hazardous materials in the manufacture of printed circuit board finishes, leads, and internal and external interconnects, PCB Fab houses had to take a fresh look at how they could clean up the business. Alternative plating finishes were the first considerations which lead to popularizing finishes such as ENIG (Electroless Nickel immersion Gold) proving that the industry can produce a PCB with excellent wettability, coplanarity and long shelf life. While many other options are available at the customer’s request at Circuits, we feel that ENIG has emerged as the cleanest, most reliable and assembly-friendly finish presently available in the market for flexible printed circuit boards.
Inner Layer Adhesion Process: Rather than using a traditional oxide treatment in the manufacture of rigid-flex, Circuits chose an innerlayer adhesion system that combines micro-etching and surface adhesion promotion to influence the flow of the pre-preg resin yielding significant interlaminar bond strength between resin and the copper surface. The COBRA Bond™ process (developed by OMG Electronic Chemicals) is designed to work with multiple types of foils, is scratch resistant and has lower overall processing costs. The COBRA Bond™ process is more environmentally sound than traditional oxide processes.
Desmear: Many PCB manufacturers today are still using a permanganate desmear process. Whereas, plasma etch not only eliminates an expensive wet line process, but also reduces water usage, treatment costs and chemical disposal. The US Environmental Protection Agency under the Design for the Environment Program conducted a case study comparing the plasma process to the permanganate desmear process and the results were dramatic. The permanganate desmear process accounted for 13% of the overall annual environmental management costs due to treatment and disposal costs for the process baths and rinses. Plasma etch is a much cleaner and more reliable process that results in a greener environment and a better quality finished product at a lower cost to our customers.
Water Treatment and Reclamation
Circuits’ is committed to minimizing the environmental impact of our PCB manufacturing operations. Our water treatment system is based on ion exchange technology that enables us to remove metallic and chemical contaminants from process water before we release it from the facility. In addition, this process allows us to effectively clean the water without generating solid hazardous wastes and to recycle valuable materials whenever possible.