The GORE MEMS Protective Vents, says the company, are designed to improve yields by addressing issues that can jeopardize the integrity of MEMS microphones during high-volume assembly of printed circuit boards for mobile phones, cameras, and other devices.
Such issues – including pressure build-up caused by the extreme heat during the solder reflow process, particle contaminants, and aerosolized solder droplets – have the potential to damage MEMS microphones, leading to acoustic performance degradation, significant yield losses, and higher manufacturing costs, says the company.
“Many manufacturers currently use non-porous tape to cover the microphone port during this process in order to prevent contaminants from entering,” says Mike Jacobs, Global Product Manager for GORE MEMS Protective Vents. “While this method is quite effective in preventing contamination, it unfortunately leaves the microphone prone to potentially damaging pressure build-up and prevents in-process acoustic testing.”
Gore’s new solution is claimed to prevent particle contamination and pressure build-up, while allowing in-process acoustic testing and integrating seamlessly into automated dispensing and placement processes. The GORE MEMS Protective Vents are designed to handle the extreme stresses of high-volume, high-speed installation, as well as multiple reflow cycles of up to 280ºC (390°F) for 40 seconds.
“The conditions a MEMS microphone is put through during high-volume assembly can often be more extreme than those in the outside world,” says Jacobs, “and even the smallest particle or pressure differential can cause irreparable damage to the MEMS microphone or significantly degrade acoustic performance.”
The protective vents provide particle protection while a breathable ePTFE membrane allows gases to pass through the microphone port to mitigate pressure build-up that may cause damage to the microphone. The vents are available in two formats:
- For Circuit Board Assembly – Style 100 allows for installation, either over the top of a top-port microphone or on the circuit board opposite a bottom-port microphone, right before the reflow process.
- For Microphone Manufacturers – Style 200 can be installed inside the MEMS microphone during the packaging process, providing particle protection without any special handling during the circuit board assembly process.
Style 100 is available in reel packaging to enable seamless installation with high-speed SMT pick and place machines. With Style 200, parts are digitally mapped in a wafer format and are compatible with high-speed die attach equipment.