Abstract: In an embodiment, a method for forming a microfabricated structure includes depositing a first membrane on a substrate, depositing a first isolation layer on the first membrane, depositing a stator layer on the first isolation layer, forming a perforated stator from the stator layer, wherein the first isolation layer is disposed on a first surface of the perforated stator, depositing a second isolation layer on a second surface of the perforated stator and depositing a second membrane on the second isolation layer, including depositing a pillar coupled between the first membrane and the second membrane, wherein the first isolation layer includes a first glass layer having a low etch rate, and a second glass layer having a high etch rate embedded in the first glass layer.

Abstract: A microfabricated structure includes a perforated stator; a first isolation layer on a first surface of the perforated stator; a second isolation layer on a second surface of the perforated stator; a first membrane on the first isolation layer; a second membrane on the second isolation layer; and a pillar coupled between the first membrane and the second membrane, wherein the first isolation layer includes a first tapered edge portion having a common surface with the first membrane, wherein the second isolation layer includes a first tapered edge portion having a common surface with the second membrane, and wherein an endpoint of the first tapered edge portion of the first isolation layer is laterally offset with respect to an endpoint of the first tapered edge portion of the second isolation layer.

Abstract: A microfabricated structure includes a perforated stator; a first isolation layer on a first surface of the perforated stator; a second isolation layer on a second surface of the perforated stator; a first membrane on the first isolation layer; a second membrane on the second isolation layer; and a pillar coupled between the first membrane and the second membrane, wherein the first isolation layer includes a first tapered edge portion having a common surface with the first membrane, wherein the second isolation layer includes a first tapered edge portion having a common surface with the second membrane, and wherein an endpoint of the first tapered edge portion of the first isolation layer is laterally offset with respect to an endpoint of the first tapered edge portion of the second isolation layer.

Abstract: A MEMS device includes a first deflectable membrane structure, a rigid electrode structure and a second deflectable membrane structure in a vertically spaced configuration. The rigid electrode structure is arranged between the first and second deflectable membrane structures. The first and second deflectable membrane structures each includes a deflectable portion, and the deflectable portions of the first and second deflectable membrane structures are mechanically coupled by mechanical connection elements to each other and are mechanically decoupled from the rigid electrode structure. At least a subset of the mechanical connection elements are elongated mechanical connection elements.

Abstract: A microfabricated structure includes a perforated stator; a first isolation layer on a first surface of the perforated stator; a second isolation layer on a second surface of the perforated stator; a first membrane on the first isolation layer; a second membrane on the second isolation layer; and a pillar coupled between the first membrane and the second membrane, wherein the first isolation layer includes a first tapered edge portion having a common surface with the first membrane, wherein the second isolation layer includes a first tapered edge portion having a common surface with the second membrane, and wherein an endpoint of the first tapered edge portion of the first isolation layer is laterally offset with respect to an endpoint of the first tapered edge portion of the second isolation layer.

Abstract: A microfabricated structure includes a perforated stator; a first isolation layer on a first surface of the perforated stator; a second isolation layer on a second surface of the perforated stator; a first membrane on the first isolation layer; a second membrane on the second isolation layer; and a pillar coupled between the first membrane and the second membrane, wherein the first isolation layer includes a first tapered edge portion having a common surface with the first membrane, wherein the second isolation layer includes a first tapered edge portion having a common surface with the second membrane, and wherein an endpoint of the first tapered edge portion of the first isolation layer is laterally offset with respect to an endpoint of the first tapered edge portion of the second isolation layer.

Abstract: A microfabricated structure includes a deflectable membrane, a first clamping layer on a first surface of the deflectable membrane, a second clamping layer on a second surface of the deflectable membrane, a first perforated backplate on the first clamping layer, and a second perforated backplate on the second clamping layer, wherein the first clamping layer comprises a first tapered edge portion having a negative slope between the first perforated backplate and the deflectable membrane.

Abstract: A microfabricated structure includes a deflectable membrane, a first clamping layer on a first surface of the deflectable membrane, a second clamping layer on a second surface of the deflectable membrane, a first perforated backplate on the first clamping layer, and a second perforated backplate on the second clamping layer, wherein the first clamping layer comprises a first tapered edge portion having a negative slope between the first perforated backplate and the deflectable membrane.

Abstract: A microfabricated structure includes a deflectable membrane, a first clamping layer on a first surface of the deflectable membrane, a second clamping layer on a second surface of the deflectable membrane, a first perforated backplate on the first clamping layer, and a second perforated backplate on the second clamping layer, wherein the first clamping layer comprises a first tapered edge portion having a negative slope between the first perforated backplate and the deflectable membrane.