Abstract: The present invention teaches a method and apparatus for removing sacrificial materials in fabrications of microstructures using one or more selected spontaneous vapor phase etchants. The selected etchant is fed into an etch chamber containing the microstructure during each feeding cycle of a sequence of feeding cycles until the sacrificial material of the microstructure is exhausted through the chemical reaction between the etchant and the sacrificial material. Specifically, during a first feeding cycle, a first amount of selected spontaneous vapor phase etchant is fed into the etch chamber. At a second feeding cycle, a second amount of the etchant is fed into the etch chamber. The first amount and the second amount of the selected etchant may or may not be the same. The time duration of the feeding cycles are individually adjustable.

Abstract: A projection system, a spatial light modulator, and a method for forming a micromirror array such as for a projection display are disclosed. The spatial light modulator can have two substrates bonded together with one of the substrates comprising a micro-mirror array. The two substrates can be bonded at the wafer level after depositing a getter material and/or solid or liquid lubricant on one or both of the wafers if desired. In one embodiment of the invention, one of the substrates is a light transmissive substrate and a light absorbing layer is provided on the light transmissive substrate to selectively block light from passing through the substrate. The light absorbing layer can form a pattern, such as a frame around an array of micro-mirrors.

Abstract: A method is disclosed for forming a micromechanical device. The method includes fully or partially forming one or more micromechanical structures multiple times on a first substrate. A second substrate is bonded onto the first substrate so as to cover the multiple areas each having one or more micromechanical structures, so as to form a substrate assembly. The substrate assembly is then separated into individual dies, each die having the one or more micromechanical structures held on a portion of the first substrate, with a portion of the second substrate bonded to the first substrate portion. Finally, the second substrate portion is removed from each die to expose the one or more micromechanical structures on the first substrate portion.

Abstract: An integrated driver for controlling operations of display systems having spatial light modulators that are operated in binary states is provided.

Abstract: A micro-mirror that comprises a substrate, a hinge structure formed on the substrate and a mirror plate attached to the hinge structure is provided for use in display systems. The mirror plate is capable of rotating from a non-deflected resting state to a state that is at least 14°, and preferably from 15° to 27° from the non-deflected resting state. In operation, the micro-mirror switches between an “ON”-state and “OFF”-state, which are defined in accordance with a rotational position of the mirror plate. The OFF state can be a non-deflected position of the micro-mirror (generally parallel to the substrate), the same angle (though opposite direction) as the ON state, or an angle less than the ON state (though in the opposite direction). Reflected light from the “ON” and “OFF” states are thus separated and the contrast ratio is improved.

Abstract: A projection system, a spatial light modulator, and a method for forming a MEMS device is disclosed. The spatial light modulator can have two substrates bonded together with one of the substrates comprising a micromirror array. The two substrates can be bonded at the wafer level after depositing a getter material andlor solid or liquid lubricant on one or both of the wafers. The wafers can be bonded together hermetically if desired, and the pressure between the two substrates can be below atmosphere.

Abstract: A micromirror device comprises a plurality of stopping mechanisms that sequentially stop the mirror plate of the micromirror device when the micromirror device is rotating towards a state, such as an ON or OFF state. The mirror plate sequentially separates from the stopping mechanisms when the mirror plate is rotating towards another state, such as the OFF or ON state.

Abstract: A micromirror device is disclosed, along with a method of making such a micromirror device that comprises a mirror plate, a hinge and an extension plate. The extension plate is formed on the mirror plate and between the mirror plate and the electrode associated with the mirror plate for rotating the mirror plate. The extension plate can be metallic or dielectric. Also disclosed is a method of making such a micromirror device. In particular, the extension plate is formed after the formation of the mirror plate. Moreover, also disclosed is a projection system that comprises a spatial light modulator having an array of such micromirrors, as well as a light source, condensing optics, wherein light from the light source is focused onto the array of micromirrors, projection optics for projecting light selectively reflected from the array of micromirrors onto a target, and a controller for selectively actuating the micromirrors in the array.

Abstract: A spatial light modulator is disclosed, along with methods for making such a modulator, that comprises an array of micromirrors each having a hinge and a micromirror plate held via the hinge on a substrate, the micromirror plate being disposed in a plane separate from the hinge and having a diagonal extending across the micromirror plate, the micromirror plate being attached to the hinge such that the micromirror plate can rotate along a rotation axis that is parallel to, but off-set from the diagonal of the micromirror plate. Also disclosed is a projection system that comprises such a spatial light modulator, as well as a light source, condensing optics, wherein light from the light source is focused onto the array of micromirrors, projection optics for projecting light selectively reflected from the array of micromirrors onto a target, and a controller for selectively actuating the micromirrors in the array.

Abstract: Methods and apparatus for selectively updating memory cells of a memory cell array are provided. The memory cells of each row of the memory cell array are provided with a plurality of wordlines. Memory cells of the row are activated and updated by separated wordlines. In an application of display systems using memory cell arrays for controlling the pixels of the display system and pulse-width-modulation (PWM) technique for displaying grayscales, the pixels can be modulated by different PWM waveforms. The perceived dynamic-false-contouring artifacts are reduced thereby. In another application, the provision of multiple wordlines enables precise measurements of voltages maintained by memory cells of the memory cell array.

Abstract: A method for processing microelectromechanical devices is disclosed herein. The method prevents the diffusion and interaction between sacrificial layers and structure layers of the microelectromechanical devices by providing selected barrier layers between consecutive sacrificial and structure layers.

Abstract: A projection system, a spatial light modulator, and a method for forming micromirrors are disclosed. A substrate comprises circuitry and electrodes for electrostatically deflecting micromirror elements that are disposed within an array of such elements forming the spatial light modulator. In one embodiment, the substrate is a silicon substrate having circuitry and electrodes thereon for electrostatically actuating adjacent micromirror elements, and the substrate is fully or selectively covered with a light absorbing material.

Abstract: A method for making a MEMS device comprises forming a plurality of micromechanical elements on a first substrate; forming circuitry and electrodes on a second substrate, the first and second substrates extending in a plane in X and Y directions; aligning the first and second substrates in the X and Y directions and moving the substrates toward each other in a Z direction and bonding the first and second substrates with a gap therebetween in the Z direction to form an assembly; singulating the assembly into assembly portions; and altering the gap for each assembly portion. Another embodiment involves aligning the first and second substrates in the X and Y directions and moving the substrates toward each other in a Z direction and bonding the first and second substrates with a gap therebetween in the Z direction to form an assembly; actuating and testing the micromechanical elements of the assembly; and altering the gap for each assembly.

Abstract: A MEMS device is disclosed comprising: a substrate; a movable micromechanical element movable relative to the substrate; a connector and a hinge for allowing movement of the micromechanical element, wherein the connector is made of a material different than the hinge. In another embodiment of the invention, the connector has a conductivity greater than the hinge. In a further embodiment of the invention, the hinge provides at least 90% of the restoring force to the MEMS device, and the connector provides 10% or less of the restoring force. In a further embodiment of the invention, the connector and the hinge have different spring constants. In a still further embodiment of the invention, the connector experiences a lower strain at maximum deflection of the micromechanical element than the hinge.

Abstract: A spatial light modulator comprising a memory cell array for use in display systems and a method of operating the memory cell array have been disclosed herein. The memory cell array comprises one or more rows of memory cells. Each row of memory cells is provided with a plurality of wordlines so that the memory cells in a row can be activated separately and independently. Memory cells connected to different wordlines in the same row, and the memory cells connected to different wordlines in different rows can be activated synchronized or asynchonized as desired. With is configuration, perceived artifacts, such as perceived dynamic-false-contouring artifacts, can be suppressed, if not eliminated. A row of reference memory cells can be formed within the memory cell array. The reference memory cells can maintain a predefined reference voltage state that is different from the voltage states maintained by the other memory cells of the memory cell array.

Abstract: A method and an improved multilayer hinge structure for use in a micromirror device for a spatial light modulator are provided herein. The micromirror device presents a conductive, composite torsion hinge with improved mechanical reliability, achieved by optimizing the geometry of the hinge, which minimizes the amount of residual twist, fixed torsional stiffness and fixed rate of plastic deformation in the mechanically undesirable hinge element. A method and its alternatives are disclosed herein by the present invention for manufacturing such multilayer hinge structure.

Abstract: An etching method, such as for forming a micromechanical device, is disclosed. One embodiment of the method is for releasing a micromechanical structure, comprising, providing a substrate; providing a sacrificial layer directly or indirectly on the substrate; providing one or more micromechanical structural layers on the sacrificial layer; performing a first etch to remove a portion of the sacrificial layer, the first etch comprising providing an etchant gas and energizing the etchant gas so as to allow the etchant gas to physically, or chemically and physically, remove the portion of the sacrificial layer; performing a second etch to remove additional sacrificial material in the sacrificial layer, the second etch comprising providing a gas that chemically but not physically etches the additional sacrificial material.

Abstract: A spatial light modulator includes an upper optically transmissive substrate held above a lower substrate containing addressing circuitry. One or more electrostatically deflectable elements are suspended by hinges from the upper substrate. In operation, individual mirrors are selectively deflected and serve to spatially modulate light that is incident to, and the reflected back through, the upper substrate. Motion stops may be attached to the reflective deflectable elements so that the mirror does not snap to the bottom substrate. Instead, the motion stop rests against the upper substrate thus limiting the deflection angle of the reflective deflectable elements.

Abstract: Methods and apparatus for producing a pulse-width-modulated (PWM) grayscale or color image using a binary spatial light modulator. By staggering and re-quantizing the PWM intervals to a clock of a period based on the frame time divided by number of rows in the display, the system's peak bandwidth requirements are optimized for displays of arbitrary resolution and arbitrary choice of PWM waveform. Additionally, a gating circuit increases the optical efficiency of a spatial light modulator using this PWM method in a field-sequential color system by reducing the duration of the blanking period between color fields.

Abstract: A projection system, a spatial light modulator, and a method for forming micromirrors are disclosed. A substrate comprises circuitry and electrodes for electrostatically deflecting micromirror elements that are disposed within an array of such elements forming the spatial light modulator. In one embodiment, the substrate is a silicon substrate having circuitry and electrodes thereon for electrostatically actuating adjacent micromirror elements, and the substrate is fully or selectively covered with a light absorbing material.