Abstract: A device for detecting the presence of particles and irregularities on the surface of a semiconductor wafer or other substrate includes a plurality of cantilevers formed on a semiconductor substrate and a means of detecting the deflection of each of the cantilevers. The cantilevers may, for example, be formed in rows and separated by selected distances. The entire substrate is then scanned over the surface to be examined, in a raster pattern, for example, and the deflection of the individual cantilevers is monitored.

Abstract: Techniques for obtaining an ejection rate independent, spatial relationship between an acoustic focal area and the free surface of a liquid. Variations in the spatial relationship are reduced or eliminated by applying substantially the same acoustic energy to the liquid's free surface during periods when droplets are not ejected as when they are, but at power levels insufficient to eject a droplet. During ejection periods in which a droplet is not ejected, the acoustic energy is applied at a lower level, but for a longer time. Because it is more convenient to measure and control, the transducer drive voltage is used to control the acoustic energy applied to the liquid's free surface.

Abstract: A scanning probe microscope is used to pattern a layer of resist, and the pattern is transferred to a substrate. First, an underlayer formed of, for example, polyimide and a top layer formed of, for example, amorphous silicon are deposited on the substrate. A pattern is formed on the top layer using the tip of the cantilever in a scanning probe microscope. The pattern may consist of an oxide formed by an electric field at the cantilever tip. The top layer is then etched using the pattern as a mask and using an etchant that is selective against the underlayer. The underlayer is then etched using an etchant that is selective against the top layer and substrate. The substrate is etched with an etchant that removes the top layer but is selective against the underlayer. Finally, the underlayer is removed.

Abstract: A fluid application device and method transfers fluid to a substrate from a fluid applicator having a plurality of ejectors. The substrate is partitioned into a matrix of cells covering the substrate and each cell includes a plurality of fluid-receiving sites. Each of the ejectors on the fluid applicator is associated with a respective one of the cells on the substrate. As fluid is ejected from the ejectors of the fluid applicator toward the substrate, the fluid applicator and substrate are moved relative to each other to cause the ejectors to scan back and forth across all of the fluid-receiving sites of each cell of the substrate. In a typical application, the fluid applicator is a printhead that ejects ink droplets toward a sheet, the printhead being approximately as large as the sheet.

Abstract: A method of depositing fluid using acoustic droplet ejectors onto a receptor until the desired layer is formed.

Abstract: A material deposition head having lithographically defined ejector units. Beneficially, each ejector unit includes a plurality of lithographically defined droplet ejectors. Furthermore, methods of fabricating such lithographically defined material deposition heads are also described.

Abstract: A method and apparatus for ejecting droplets from the crests of capillary waves riding on the free surface of a liquid by parametrically pumping the capillary waves with electric fields from probes located near the crests. Crest stabilizers are beneficially used to fix the spatial locations of the capillary wave crests near the probes. The probes are beneficially switchably connected to an AC voltage supply having an output that is synchronized with the crest motion. When the AC voltage is applied to the probes, the resulting electric field adds sufficient energy to the system so that the surface tension of the liquid is overcome and a droplet is ejected. The AC voltage is synchronized such that the droplet is ejected about when the electric field is near is minimum value. A plurality of droplet ejectors are arranged and the AC voltage is switchably applied so that ejected droplets form a predetermined image on a recording surface.

Abstract: A photolithography system includes a plurality of cantilevers, preferably formed in a silicon wafer. Each cantilever includes a tip located near the free end of the cantilever and a waveguide which extends along the length of the cantilever and intersects the tip. An aperture is formed at the apex of the tip so that light travelling through the waveguide may exit the tip. A light switch is included in the waveguide to control the passage of light to the tip of the cantilever.The array of cantilevers is positioned adjacent a wafer which is to be lithographed, in the manner of an atomic force microscope operating in the attractive mode. Each cantilever is a compound structure, including a thick portion and a thin portion, the latter having a preselected mechanical resonant frequency.

Abstract: A device for moving an object, such as a sheet of paper or other substrate, includes a base element, a drive mechanism to move the base element in first and second directions, such as by vibration, and a plurality of flexible ratchets fixedly secured to the base element. As the base element vibrates, the ratchets advance the sheet of paper in a direction perpendicular to the direction of vibration of the base element. Pluralities of base elements and drive mechanisms can be provided to direct movement of the substrate in various directions.

Abstract: A near field scanning optical microscope (NSOM) includes a cantilever which is aligned generally parallel to the surface of a sample. An optical waveguide extends along the cantilever to a tip which protrudes downward from the cantilever. A small aperture at the apex of the tip allows light radiation flowing through the waveguide to be directed toward the sample. The cantilever is vibrated, and variations in its resonant frequency are detected and delivered to a feedback control system to maintain a constant separation between the tip and the sample. The NSOM can also be operated as an atomic force microscope in either a contact or non-contact mode.

Abstract: An acoustic microscope assembly for atomic level inspection of a target object includes a cantilever arm with a sharp tip on its lower surface and a zinc oxide piezoelectric thin film on its upper surface. High frequency excitation signals, having a frequency of at least 50 Megahertz, are applied to the piezoelectric thin film so as to generate high frequency acoustic signals that are transmitted through the sharp tip so as to impact on a target object. The assembly can either receive acoustic signals reflected by the target object, or it can receive acoustic signals that have propagated through the target object. One method of using this assembly is to apply a continuous wave signal to the piezoelectric thin film while scanning the target object, and measuring characteristics of the target object at various positions thereof by measuring the resonant frequency of the transmitted high frequency acoustic signals.

Abstract: A integrated mass memory device is formed by combining a piezoelectric bimorph cantilever (214) with a recording surface (212) having a number of storage locations to and from which digital information is transferred using a scanning tunneling microscope or an atomic force microscope mode of operation. Controls circuits (240) are provided for controlling the scanning of the recording surface (212) and for writing and reading information into and from the recording surface. An image storage system stores images captured from an optical sensor using piezoelectric bimorph cantilevers for reading and writing digital information on recording surfaces.

Abstract: A traveling wave droplet generator having a drop-on-demand mode of operation. An acoustic mechanism excites a line of peaks of ink just below threshold for ink drop ejection in the orifices of an ink chamber. Electrostatic means raises particular peaks above the threshold using an excitation that is synchronous with the acoustic wave, which gives rise to parametric coupling which enhances the efficiency of the ejection. The electrostatic field can be selectively established at each of the orifices by a conventional addressing mechanism.

Abstract: A vacuum cleaner for helping maintain the cleanliness of the exposed surfaces of an ink jet droplet ejector. The vacuum cleaner is comprised of a top cover plate, having a plurality of air passages, that is located over a channel surface by spacers. A vacuum means draws the pressure in the defined volume between the top cover plate, the channel surface, and the spacers below the external pressure, whereby air is drawn into the defined volume through the air passages. The resulting air flow removes ink, dust, and debris from the vicinity of the exposed surfaces, thereby helping to maintain the cleanliness of the droplet ejector. The top cover plate and spacers are beneficially formed using silicon microstructure fabrication techniques.

Abstract: This invention is an acoustic ink printer. It has a pool of ink (33) with a free surface (36). Underneath the ink is a print head (10) which has droplet ejectors (14) for irradiating the free surface (36) of the pool of ink (33) with focused acoustic radiation (44). Over the free surface (36) of the pool of ink (33) is a membrane (16), with one or more apertures (20) aligned with the droplet ejectors (14), in intimate contact with the free surface (36) of the pool of ink (33). The apertures 20 are substantially larger than the waist diameter (46) of the focused acoustic radiation (44). An external pressure source (50) maintains the meniscus (48) of the pool of ink (33) substantially in the focal plane (52) of the focused acoustic radiation (44) during operation of the droplet ejectors (14). A piezoelectric crystal (24) is in intimate contact with the pool of ink (33).

Abstract: The free ink surface levels of acoustic ink printers are controlled by cap structures that have substantially non-retroreflective aperture configurations. The non-retroreflective configurations of the apertures of these cap structures cause diffusive scattering or directional deflection of the reflected surface ripple waves, thereby significantly reducing the time that is required for the oscillatory perturbations, which are caused by reflection of the surface ripple waves that are generated during the droplet ejection process, to dissipate to a negligibly low amplitude in the critical local areas of the ejection sites. This, in turn, increases the droplet ejection rates at which printers having such cap structures can be operated asynchronously.

Abstract: An ejector for ejecting droplets from an ink-filled reservoir is disclosed. The ejector comprises a substrate with a generally planar surface. The substrate is submerged in the reservoir so that the substrate surface is parallel to the reservoir surface at a shallow predetermined depth. On the substrate surface around a center is a plurality of concentric, circular electrodes. A coupled oscillator excites the electrodes in a temporal relationship such that the capillary waves generated at the ink reservoir surface are reinforced so that droplets may be ejected from the reservoir at the center of the electrodes.

Abstract: The ejection of droplets in an ink jet printer is accompanied by the generation of capillary waves that spread out radially from the central region where the drops are ejected. These capillary waves interfere with the ejection of succeeding droplets. In order to suppress these capillary waves, the pressure in the pool of liquid feeding the printer is varied periodically at twice the maximum repetition rate of droplet ejection.

Abstract: An apparatus and methods for using a Variable Orifice Capillary Wave Printer are disclosed. The invention as described herein provides a capability to transfer high resolution graphical images onto a projection medium (14) with pseudo-gray-scale (i.e. variable spot-size). A standing fluid ripple wave (38) or capillary wave is generated along a narrow channel (20) at the top of an ink reservoir (16), upon the free fluid surface (27). The capillary wave (38) is spatially stablized with an elongated slotted bar (30) of anisotropically etched signal crystal silicon. Piezoelectric pushers (34) are positioned at the anti-nodes (42) of the stabilized standing capillary wave (38) to selectively restrict the narrow slots (32) etched into the slotted silicon bar (30). Selective actuation of one or more piezoelectric pusher (34) for a predetermined length of time results in the ejection of a stream of fluid droplets (12).

Abstract: Method and apparatus for storing digital information in a dense memory structure. A semiconductor substrate has a thin insulating layer formed thereon. Over the thin insulating layer is formed a dielectric charge-storage layer. A piezoelectric bimorph cantilever arm has a tip formed at its free end to access certain memory sites defined by charge-storage regions in the charge-storage layer. To write infromation in the form of charges into a memory site the tip contacts or is in close proximity to the surface of the charge-storage layer and an electric field is applied between the tip and the substrate to induce charges to tunnel through the thin insulating layer into the charge-storage layer where the charges are stored as trapped charges. Information is read from a storage-site by spacing the tip of the cantilever arm a distance from the surface of the charge storage layer and applying an electric field between the tip and the substrate.