Electrodes for microelectromechanical system microphones

A microelectromechanical system (MEMS) sensor comprising:

• a membrane;
• a membrane electrode formed in a portion of the membrane;
• and
• a backplate situated parallel to the membrane and separated by a gap, the backplate comprising:
• a central region of the backplate positioned about a center point of the backplate, the central region of the backplate comprising:
• a first sub-region (1910) having formed therein first holes having a first hole pitch;
• and
• a second sub-region (1920) that is positioned outside the first sub-region relative to the center point of the backplate, the second sub-region having formed therein second holes having a second hole pitch that is smaller than the first hole pitch;
• and
• a backplate electrode formed in a portion of the central region of the backplate, wherein a portion of the membrane electrode overlaps a portion of the backplate electrode in a sensing region (110) forming a sensing capacitor, the sensing capacitor being configured to sense motion of the membrane in response to acoustic pressure.