Abstract: The efficiency of an etching process may be increased in various ways, and the cost of an etching process may be decreased. Unused etchant may be isolated and recirculated during the etching process. Etching byproducts may be collected and removed from the etching system during the etching process. Components of the etchant may be isolated and used to general additional etchant. Either or both of the etchant or the layers being etched may also be optimized for a particular etching 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: Air gap variation in an interferometric modulator over a two-dimensional spatial map of the modulator is determined by acquiring a digital photograph of the modulator. Color parameters of individual pixels in the photograph are determined and compared to a model of color parameters as a function of air gap distance. The model and individual pixel color parameters may be plotted on a color space plot for comparison. The determined distances may be plotted over a two-dimensional spatial map of the interferometric modulator to visualize the mirror curvature and air gap variation.

Abstract: An optical interference display unit with a first electrode, a second electrode and support structures located between the two electrodes is provided. The second electrode has at least a first material layer and a second material layer. At least one material layer of the two is made from conductive material and the second conductive layer is used as a mask while an etching process is performed to etch the first material layer to define the second electrode.

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, devices, and systems provide MEMS devices exhibiting at least one of reduced stiction, reduced hydrophilicity, or reduced variability of certain electrical characteristics using MEMS devices treated with water vapor. The treatment is believed to form one or more passivated surfaces on the interior and/or exterior of the MEMS devices. Relatively gentle temperature and pressure conditions ensure modification of surface chemistry without excessive water absorption after removal of sacrificial material to release the MEMS devices.

Abstract: An optical interference display panel is disclosed that has a substrate, an optical interference reflection structure, and an opaque protection structure. The optical interference reflection structure has many color-changeable pixels and is formed on the substrate. The opaque protection structure is adhered and fixed onto the substrate with an adhesive and encloses the optical interference reflection structure between the substrate and the opaque protection structure. The opaque protection structure blocks and/or absorbs light, and light is thus not emitted outward by passing through defects in the optical interference reflection structure. Moreover, the opaque protection structure and the adhesive also prevent the optical interference reflection structure from being damaged by an external environment.

Abstract: A light modulator device includes a first electrical conduit, a second electrical conduit electrically isolated from the first conduit, a first display element, and a second display element. The first display element is in an actuated state when a voltage difference between the first conduit and the second conduit has a magnitude greater than a first actuation voltage and is in a released state when the voltage difference has a magnitude less than a first release voltage. The second display element is in an actuated state when the voltage difference has a magnitude greater than a second actuation voltage and is in a released state when the voltage difference has a magnitude less than a second release voltage. Either the actuation voltages are substantially equal and the release voltages are different, or the actuation voltages are different and the release voltages are substantially equal.

Abstract: Methods of making a microelectromechanical system (MEMS) device are described. In some embodiments, the method includes forming a sacrificial layer over a substrate, treating at least a portion of the sacrificial layer to form a treated sacrificial portion, forming an overlying layer over at least a part of the treated sacrificial portion, and at least partially removing the treated sacrificial portion to form a cavity situated between the substrate and the overlying layer, the overlying layer being exposed to the cavity.

Abstract: A method of creating an internal dipole moment in an interferometric light modulating device is disclosed. In certain embodiments, the method includes applying heat and an electrical field to a dielectric layer of an interferometric light modulating device. Before this method, the dielectric layer has mobile charges or includes random dipoles. After this method, however, those random dipoles are substantially aligned, thereby inducing a fixed dipole moment in the dielectric layer. The electric field creates the dipole moment in the dielectric layer and the heat helps increase the speed of the process by supplying additional activation energy. Having a dielectric layer with an induced dipole moment provides an internal voltage source that provides at least a portion of the voltage required to operate the interferometric light modulating device. The induced dipole moment also reduces the possibility of an uncontrolled shift of charge within the device during operation.

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 display device including a plurality of optical modulators and a plurality of filter elements on a reflective side of the plurality of optical modulators is provided. The plurality of optical modulators includes a first set of optical modulators and a second set of optical modulators. Each optical modulator of the plurality of optical modulators is configured to be selectively switched among at least a first state, a second state, and a third state. Each state has a different spectral reflectance. The plurality of filter elements includes a first set of filter elements corresponding to the first set of optical modulators and a second set of filter elements corresponding to the second set of optical modulators. The first set of filter elements has a different spectral transmittance than the second set of filter elements.

Abstract: A front light guide panel including a plurality of embedded surface features is provided. The front light panel is configured to deliver uniform illumination from an artificial light source disposed at one side of the font light panel to an array of display elements located behind the front light guide while allowing for the option of illumination from ambient lighting transmitted through the light guide panel. The surface embedded surface relief features create air pockets within the light guide panel. Light incident on the side surface of the light guide propagates though the light guide until it strikes an air/light material guide interface at one on the air pockets. The light is then turned by total internal reflection through a large angle such that it exits an output face disposed in front of the array of display elements.

Abstract: A microelectromechanical (MEMS) device is presented which comprises a metallized semiconductor. The metallized semiconductor can be used for conductor applications because of its low resistivity, and for transistor applications because of its semiconductor properties. In addition, the metallized semiconductor can be tuned to have optical properties which allow it to be useful for optical MEMS devices.

Abstract: The fabrication of a MEMS device such as an interferometric modulator is improved by employing an etch stop layer between a sacrificial layer and a an electrode. The etch stop may reduce undesirable over-etching of the sacrificial layer and the electrode. The etch stop layer may also serve as a barrier layer, buffer layer, and/or template layer. The etch stop layer may include silicon-rich silicon nitride.

Abstract: A microelectromechanical system (MEMS) is provided. In one embodiment, the MEMS includes a transparent substrate, and a plurality of interferometric modulators. The plurality of interferometric modulators includes an optical stack coupled to the transparent substrate, in which the optical stack includes a first light absorbing area. The plurality of interferometric modulators further includes a reflective layer over the optical stack, and one or more posts to support the reflective layer. Each of the one or more posts includes a second light absorbing area integrated in the post.

Abstract: A microelectromechanical device (MEMS) utilizing a porous electrode surface for reducing stiction is disclosed. In one embodiment, a microelectromechanical device is an interferometric modulator that includes a transparent electrode having a first surface; and a movable reflective electrode with a second surface facing the first surface. The movable reflective electrode is movable between a relaxed and actuated (collapsed) position. An aluminum layer is provided on either the first or second surface. The aluminum layer is then anodized to provide an aluminum oxide layer which has a porous surface. The porous surface, in the actuated position, decreases contact area between the electrodes, thus reducing stiction.

Abstract: The invention comprises devices and methods for determining residual stress in MEMS devices such as interferometric modulators. In one example, a device measuring residual stress of a deposited conduct material includes a material used to form a MEMS device, and a plurality of disconnectable electrical paths, wherein said plurality of paths are configured to disconnect as a function of residual stress of the material. In another example, a method of measuring residual stress of a conductive deposited material includes monitoring a plurality of signals, each of said plurality of signals being associated with one of a plurality of test structures, said plurality of test structures each being configured to change the associated signal upon being subject to a predetermined amount of residual stress, sensing a change in said plurality of signals, and determining a residual stress level in said material based on the sensed change in the plurality of signals.

Abstract: A microelectromechanical device (MEMS) utilizing a porous electrode surface for reducing stiction is disclosed. In one embodiment, a microelectromechanical device is an interferometric modulator that includes a transparent electrode having a first surface; and a movable reflective electrode with a second surface facing the first surface. The movable reflective electrode is movable between a relaxed and actuated (collapsed) position. An aluminum layer is provided on either the first or second surface. The aluminum layer is then anodized to provide an aluminum oxide layer which has a porous surface. The porous surface, in the actuated position, decreases contact area between the electrodes, thus reducing stiction.

Abstract: Various embodiments of the invention include an interferometric optical modulator comprising a substrate layer and a light direction layer. Such an interferometric modulator may be integrated with a diffuser layer in a display device in a way that physically integrates the diffuser layer into the light direction layer in a way where the diff-user layer does not interact with light propagating within the light direction layer. As a result, most of the light propagating within the light direction layer does not penetrate into the diffuser which would inhibit performance of the display. In some embodiments, the interface between the diffuser layer and the light direction layer has a lower index of refraction than the light direction layer and the transparent substrate so that total internal reflection occurs at the interface.