Abstract: A microelectromechanical system (MEMS) apparatus includes a base. A MEMS device is disposed on the base. A cover encloses the MEMS device on the base. A port extends through the base, and the MEMS device is disposed over the port. A diaphragm is embedded within the base and has at least some portions that extend across the port. In an open position, the diaphragm allows the passage of sound energy from the exterior of the apparatus to the interior of the apparatus. In a closed position, the diaphragm makes contact with an outer surface of the port to at least partially block the passage of sound energy from the exterior of the apparatus to the interior of the apparatus.

Abstract: A microphone assembly includes a base, a cover, and a microelectromechanical system (MEMS) die. The cover extends at least partially over and is coupled to the base. The cover and the base form a cavity. The MEMS die is coupled to the base and disposed within the cavity. At least a portion of the cover is constructed of a copper-nickel-zinc alloy that is effective in preventing solder from moving from a first portion of the cover to a second portion of the cover.

Abstract: A method for fabricating thick film alumina structures used in high frequency, low loss applications is provided. More particularly, the invention is directed to a co-fire process for fabricating, or laminating, thick film structures to one another by printing a conductor layer between two thick film circuits, drying the layer, and co-firing the combined structure. This process is particularly useful in fabricating high frequency (e.g. 10 gigabit) fiber optic transmitters.