Abstract: A microelectromechanical systems device having an electrical interconnect between circuitry outside the device and at least one of an electrode and a movable layer within the device. At least a portion of the electrical interconnect is formed from the same material as a conductive layer between the electrode and a mechanical layer of the device. In an embodiment, this conductive layer is a sacrificial layer that is subsequently removed to form a cavity between the electrode and the movable layer. The sacrificial layer is preferably formed of molybdenum, doped silicon, tungsten, or titanium. According to another embodiment, the conductive layer is a movable reflective layer that preferably comprises aluminum.

Abstract: An interferometric modulator is formed by a stationary layer and a mirror facing the stationary layer. The mirror is movable between the undriven and driven positions. Landing pads, bumps or spring clips are formed on at least one of the stationary layer and the mirror. The landing pads, bumps or spring clips can prevent the stationary layer and the mirror from contacting each other when the mirror is in the driven position. The spring clips exert force on the mirror toward the undriven position when the mirror is in the driven position and in contact with the spring clips.

Abstract: Embodiments of MEMS devices comprise a conductive movable layer spaced apart from a conductive fixed layer by a gap, and supported by rigid support structures, or rivets, overlying depressions in the conductive movable layer, or by posts underlying depressions in the conductive movable layer. In certain embodiments, portions of the rivet structures extend through the movable layer and contact underlying layers. In other embodiments, the material used to form the rigid support structures may also be used to passivate otherwise exposed electrical leads in electrical connection with the MEMS devices, protecting the electrical leads from damage or other interference.

Abstract: A method for etching a target material in the presence of a structural material with improved selectivity uses a vapor phase etchant and a co-etchant. Embodiments of the method exhibit improved selectivities of from at least about 2-times to at least about 100-times compared with a similar etching process not using a co-etchant. In some embodiments, the target material comprises a metal etchable by the vapor phase etchant. Embodiments of the method are particularly useful in the manufacture of MEMS devices, for example, interferometric modulators. In some embodiments, the target material comprises a metal etchable by the vapor phase etchant, for example, molybdenum and the structural material comprises a dielectric, for example silicon dioxide.

Abstract: Embodiments of the present disclosure include a method of fabricating interferometric devices using lift-off processing techniques. Use of lift-off processing in the fabrication of various layers of interferometric modulators, such as an optical stack or a flex layer, advantageously avoids individualized chemistries associated with the plurality of materials associated with each layer thereof. Moreover, use of lift-off processing allows much greater selection in both materials and facilities available for fabrication of interferometric modulators.

Abstract: MEMS devices such as interferometric modulators are described having movable layers that are mechanically isolated. The movable layers are electrically attractable such that they can be selectively moved between a top and bottom electrode through application of a voltage. In interferometric modulators, the movable layers are reflective such that an optically resonant cavity is formed between the layer and a partially reflective layer, thereby providing a display pixel that can be turned on or off depending on the distance between the reflective layers in the resonant cavity.

Abstract: Methods and apparatus are provided for controlling a depth of a cavity between two layers of a light modulating device. A method of making a light modulating device includes providing a substrate, forming a sacrificial layer over at least a portion of the substrate, forming a reflective layer over at least a portion of the sacrificial layer, and forming one or more flexure controllers over the substrate, the flexure controllers configured so as to operably support the reflective layer and to form cavities, upon removal of the sacrificial layer, of a depth measurably different than the thickness of the sacrificial layer, wherein the depth is measured perpendicular to the substrate.

Abstract: A method of manufacturing a microelectromechanical device includes forming at least two conductive layers on a substrate. An isolation layer is formed between the two conductive layers. The conductive layers are electrically coupled together and then the isolation layer is removed to form a gap between the conductive layers. The electrical coupling of the layers mitigates or eliminates the effects of electrostatic charge build up on the device during the removal process.

Abstract: A microelectromechanical devices with protective coatings on one or more surfaces of the micromechanical device is disclosed. The micromechanical device includes a substrate. The micromechanical device further includes a mirror positioned over the substrate. The mirror can be at least partially reflective to incident light. The micromechanical device further includes an optical layer positioned over the substrate and spaced from the mirror. The optical layer can be at least partially transmissive to incident light. The micromechanical device can further include a protective coating. The optical layer and the mirror define a cavity and the protective coating overlies surfaces of the microelectromechanical device exposed to the cavity.

Abstract: A MEMS test device comprises a flexible beam spaced apart from an optical stack. The MEMS test device includes a reflective layer and a partially reflective layer, such that a change in the position of the MEMS test device can be observed without the use of an external interferometer. The flexible beam may be cantilevered or fixed at each end. The flexible beam may include a shoe suspended from the side of the beam facing the optical stack, to provide a fixed contact area. An array of MEMS test devices may be used to determine compliance, or to calculate adhesion forces.

Abstract: An interferometric modulator is formed by a stationary layer and a mirror facing the stationary layer. The mirror is movable between the undriven and driven positions. Landing pads, bumps or spring clips are formed on at least one of the stationary layer and the mirror. The landing pads, bumps or spring clips can prevent the stationary layer and the mirror from contacting each other when the mirror is in the driven position. The spring clips exert force on the mirror toward the undriven position when the mirror is in the driven position and in contact with the spring clips.

Abstract: A method of manufacturing a microelectromechanical device includes forming at least two conductive layers on a substrate. An isolation layer is formed between the two conductive layers. The conductive layers are electrically coupled together and then the isolation layer is removed to form a gap between the conductive layers. The electrical coupling of the layers mitigates or eliminates the effects of electrostatic charge build up on the device during the removal process.

Abstract: Embodiments of the present invention relate to interferometric display devices comprising an interferometric modulator and a solar cell and methods of making thereof. In some embodiments, the solar cell is configured to provide energy to the interferometric modulator. The solar cell and the interferometric modulator may be formed above the same substrate. A layer of the solar cell may be shared with a layer of the interferometric modulator.

Abstract: Methods of forming a protective coating on one or more surfaces of a microelectromechanical device are disclosed comprising the steps of forming a composite layer of a sacrificial material and a protective material, and selectively etching the sacrificial material to form a protective coating. The protective coatings of the invention preferably improve one or more aspects of the performance of the microelectromechanical devices in which they are incorporated. Also disclosed are microelectromechanical devices formed by methods of the invention, and visual display devices incorporating such devices.

Abstract: A microelectromechanical system (MEMS) device includes a reflective element that includes at least one stop member. The device also includes an electrode and an aperture that extends at least partially through the electrode. The aperture has a boundary. The device has an electrically nonconductive surface within the aperture or on a portion of the boundary of the aperture. A support structure separates the reflective element from the electrode. The reflective element can be moved between a first position and a second position. The stop member is spaced from the electrically nonconductive surface when the reflective element is in the first position. A portion of the stop member is in contact with the electrically nonconductive surface when the reflective element is in the second position. The reflective element and the electrode are electrically isolated from each other when the reflective element is in the second position.

Abstract: Methods for making MEMS devices such as interferometric modulators involve selectively removing a sacrificial portion of a material to form an internal cavity, leaving behind a remaining portion of the material to form a post structure. The material may be blanket deposited and selectively altered to define sacrificial portions that are selectively removable relative to the remaining portions. Alternatively, a material layer can be laterally recessed away from openings in a covering layer. These methods may be used to make unreleased and released interferometric modulators.

Abstract: Certain MEMS devices include layers patterned to have tapered edges. One method for forming layers having tapered edges includes the use of an etch leading layer. Another method for forming layers having tapered edges includes the deposition of a layer in which the upper portion is etchable at a faster rate than the lower portion. Another method for forming layers having tapered edges includes the use of multiple iterative etches. Another method for forming layers having tapered edges includes the use of a liftoff mask layer having an aperture including a negative angle, such that a layer can be deposited over the liftoff mask layer and the mask layer removed, leaving a structure having tapered edges.

Abstract: Methods for making MEMS devices such as interferometric modulators involve selectively removing a sacrificial portion of a material to form an internal cavity, leaving behind a remaining portion of the material to form a post structure. The material may be blanket deposited and selectively altered to define sacrificial portions that are selectively removable relative to the remaining portions. Alternatively, a material layer can be laterally recessed away from openings in a covering layer. These methods may be used to make unreleased and released interferometric modulators.

Abstract: An optical device for modulating the intensity of light from an interferometric reflector. In one embodiment, the optical device can include an optical stack having a reflective layer and a partially reflective, partially transmissive layer for reflecting light. The optical device can also include a fluid cell comprising an absorptive fluid and a transmissive fluid. The optical device can also include a mechanism for controlling the portion of the reflector which is shadowed by the absorptive fluid.

Abstract: An interferometric modulator includes a post structure comprising an optical element. In a preferred embodiment, the optical element in the post structure is a reflective element, e.g., a mirror. In another embodiment, the optical element in the post structure is an etalon, e.g., a dark etalon. The optical element in the post structure may decrease the amount of light that would otherwise be retroreflected from the post structure. In various embodiments, the optical element in the post structure increases the brightness of the interferometric modulator by redirecting light into the interferometric cavity. For example, in certain embodiments, the optical element in the post structure increases the backlighting of the interferometric modulator.