Assembly in Action: Automation Meets Optoelectronics Assembly Challenge
Because the packaging portion of an optoelectronic device can be costly, processes that can be handled by automated equipment can produce cost savings. Therefore, Iolon designs its products and manufacturing systems with automation in mind.
The company installed two Model 3500-II automatic component assembly cells from Palomar Technologies Inc. (Vista, CA) with accessories to automate critical process steps.
"Our corporate philosophy is to design for manufacture and design for automation," says Tim Harris, vice president of operations. "Time-to-volume is important. It doesn’t do our customers or us any good to have the best technology if we cannot rapidly respond to our customer’s demands. Furthermore, automation is the best way to eliminate the quality, reliability and yield problems that can arise from a rapid increase in production in a manual assembly process."
Before automating, the operators used tweezers, tooling and templates to place optical components onto a ceramic substrate, attach each component to the substrate and place the ceramic into the package, which was then hermetically sealed. With this method, it was difficult to guarantee consistent product quality. Even with high-powered microscopes, optical grids and video targeting, the assisted human hand produces process variations that result in yield loss and degradation of laser performance. New operators needed extensive training to learn the process. Rapid increases in production were difficult.
"By using automation, you make every part the same," says Joe Drake, vice president of engineering. "It’s not something that’s sensitive to an operator’s learning curve. We have taken that whole problem off the table."
The tolerances for optical component assembly are exceptionally stringent, with required X-Y accuracies measured in microns or nanometers. Rotational accuraciesincluding roll, pitch and yaware specified in tenths of degrees. These strict tolerances are a challenge that automated equipment must overcome to support optoelectronic assembly. Final positioning accuracy is critical.
Iolon’s optoelectronic component assembly requires an accurate, true position radial placement of components, which includes X, Y and theta positioning accuracy. With automation, the company was able to surpass its requirements and achieve a 3 Sigma accuracy for final theta alignment of 0.41 degree.
In addition to precision and tolerance control, Iolon needed to run many process steps on the same equipment to produce all the products enabled by their platform technology.
"Whether it is an L- or C-band tunable laser or tunable filter, we needed a piece of equipment that would be flexible, and that on a real-time basis, we can switch quickly between products based on customer demand," says Eric Allison, director of operations. "What that translates to for the customer is that we can provide an extremely reliable laser regardless of whether it is C or L band in the shortest turnaround time possible."
Iolon now uses automated equipment to pick and place components on its tunable laser. A flexible, computer-controlled workcell performs adhesive dispensing, as well as substrate and component placement. Trays of components can be lined up to keep the line running continuously.
An important benefit of automation is reduced labor cost. By automating critical processes, the company achieved a 10-to-1 productivity improvement as measured in units per labor hour. Under the former manual system, the company would have to hire, train and manage a large number of operators. With the automation equipment, one primary operator and a backup operator perform the entire operation.
The company also saved labor costs by limiting the number of active alignment steps. Typical multicomponent optoelectronic devices require active alignment on each component that is installed. Between the automation equipment and Iolon’s designs, the end result is a tunable laser with an integrated wavelength locker requiring only two active alignment steps.
"For us, automation is not conveyors connecting various process steps," says Drake. "Automation is carrying out very critical process steps exactly right, reproducibly, and with flexibility and cost-effectiveness."
For more information on automated assembly cells, call 760-931-3600 or visit www.palomartechnologies.com.