During the Fall 2015 semester, the Fraunhofer Center for Coatings and Diamond Technologies (Fraunhofer USA CCD) elected to sponsor a team of four MSU Electrical and Computer Engineering students in their semester-long senior design project: Monitoring of a Diamond Polishing System. CCD project engineer Aaron Hardy familiarized the design team with the polishing equipment and facilitated visits for data collection and in-situ testing throughout the semester. The team, consisting of Paul Dionese, Alex Kohler, Rohan Panda, and Anthony Garvert, developed a microphone-based system to monitor the polishing acoustically.
Mechanical polishing of single and polycrystalline diamond are routine tasks at Fraunhofer USA CCD. Whether the polished sample is needed for optical analysis, as a substrate for additional diamond growth, or as an electrode where contacts will be annealed, polishing is a critical step. The smoothness of the polished surface can determine the success or failure of all subsequent steps; therefore, a system for monitoring the progress of diamond polishing would be immensely useful for process development toward smoother and more consistent polished diamond surfaces.
Equipped with a microphone and an accelerometer, the design team created a device that would send frequency data through an Arduino UNO board to a digital display, and optionally, to a computer connected via USB. The accelerometer attaches to the polishing arm and serves as an alarm system, triggering a horn if the output exceeds a certain threshold. The power supply and microphone amplifier were designed in EAGLE and made into a PCB.
MSU College of Engineering’s Design Day is a valuable opportunity for students to apply the skills they have gained in the classroom to real-world, sponsored projects. Fraunhofer USA CCD is grateful for the opportunity to sponsor such a team and looks forward to more collaboration in the future.
