Michael Van Belle
Thanks to researchers at the University of Michigan, manufacturers of microelectronics used in laser production soon will have access to a device that will for the first time allow critical analysis of key aspects of the process.
"Microelectronics is pushing the scale of miniaturization to smaller and smaller levels," said John Bilello, one of two researchers in the university's department of materials science and engineering. "The ability to gain quality control at these levels is critical for business in the United States, as microelectronics and aviation are really the nation's bread-and-butter industries."
The device created by Bilello and fellow researcher Steven Yalisove monitors the sputtering method of coating materials for strength and corrosion resistance. In the past, the high level of precision required has prevented such monitoring. "Electron optics are useless in sputtering, but we needed the same kind of quantitative analytical tools used to assess growth in near real time as semiconductor makers have been using," Bilello said.
Monitoring many characteristics
This is what the researchers have achieved, according to Bilello. "The device bounces x-rays off the atoms being deposited during sputtering, allowing us to measure the fraction parts that give us information on phases, strain and microchemistry all at once."
Observing this process is critical to quality control issues in microelectronics manufacturing, Bilello added, because every target put into production has completely different parameters that change for different processes, such as widely varying temperatures. "Any different methods for getting better control and better feedback means that chances get much better that product failure will not occur," he said.
For the laser industry, the device creates a technique for ensuring quality control, Bilello said. "Not only can it be used in the microelectronics manufacturing, but in the lasers themselves to achieve excellent quality control. It's a way to calibrate exactly what is happening, and that same calibration technique can be used for other methods and products using fiber optics," he added.
Bilello and Yalisove also plan to develop a more portable, small-scale system, and will make a full paper on the process available soon. Funding came from the US Army Research Office and the Defense Advanced Research Projects Agency.