Abstract: In order to facilitate the alignment of a mask with a substrate on which the mask is to be imaged, a rectangular window on the mask is projected through a semitransparent mirror and an optical objective upon an area of the substrate carrying a line mark parallel to two edges of the window. The image of the window is retroprojected through the same objective, along with the associated line mark, and is focused via the semitransparent mirror upon a detection plane of an evaluator where the resulting composite image is scanned in a direction perpendicular to the line mark to determine the position of that mark relative to the window edges. The same scan, on traversing each window edge, yields a signal representing sharpness of focus in terms of the time required for passing between two predetermined thresholds of light intensity; the latter signal is used for adjusting the relative distance of the object and image surfaces respectively constituted by the mask and the substrate.

Abstract: In the photoexposure of semiconductor wafers for the production of circuit elements, the wafers are placed in a prealignment position before being transferred to the exposure stage. A chuck acting as a prepositioning stage is rotatable by one servomotor to set the wafer in its appropriate angular position (.phi. adjustment) and is shiftable by respective servomotors in the X and Y directions. Servomotor control is effected by optical means detecting a noncircular edge portion of the wafer as well as alignment marks on the wafer inwardly of the edge thereof.

Abstract: A dosing pump for metering a predetermined quantity of a displaceable material, usually a solvent-containing fluid substance, per stroke of the pump, comprises a chamber connected by an intake valve with a source of the material and with a discharge valve with a location into which the material is to be dispensed. The chamber is provided with a drive member, e.g. a membrane or piston, preferably actuatable by fluid pressure and, according to the invention, at least one displaceable member whose stroke is such that it corresponds to a displacement of material less than the displacement by the drive member and is effective upon retraction of the drive member to allow the material to recede slightly from the outlet of the pump without re-entering the chamber.

Abstract: A support for a semiconductor wafer about to be subjected to exposure through a photomask, e.g. a rotatable chuck, comprises a stage to which the wafer is temporarily adhered by suction and whose temperature is controlled by an array of Peltier elements responsive to a thermoelectric sensor disposed close to the wafer-carrying stage surface. The Peltier elements are horizontally arrayed in a rectangular block inserted between the stage and an underlying base of the support, the block being cemented into a metal frame which has only limited contact with the stage and the base to minimize heat conduction therebetween. The base has channels for the circulation of a temperature-modifying fluid such as water.

Abstract: In the projection-copying of a mask on a workpiece including a light-reflecting semiconductor substrate, the alignment of mask and workpiece is effected by illuminating marks on the substrate which appear dark relative to a surrounding area. To provide each mark with a contrasting background of sufficient brightness, a partly reflecting surface layer overlying the substrate in that area has a nonuniform optical thickness whereby cancellation of reflections due to interference is limited to isolated regions.

Abstract: A planar, solid, light-transmitting coating (7) is applied directly to a photoresist layer (6) before the exposure of the latter in the production of integrated circuits by photolithography. Any dust particles will thus be held separated from the photoresist layer (6) by a distance at which they are less effective optically. The probability of the occurrence of standing waves is reduced by increasing the total thickness of the combined layer (6+7) covering the semiconductor (5) proper.

Abstract: In the photoexposure of semiconductor wafers for the production of circuit elements, the wafers are placed in a prealignment position before being transferred to the exposure stage. A chuck acting as a prepositioning stage is rotatable by one servomotor to set the wafer in its appropriate angular position (.phi. adjustment) and is shiftable by respective servomotors in the X and Y directions. Servomotor control is effected by optical means detecting a noncircular edge portion of the wafer as well as alignment marks on the wafer inwardly of the edge thereof.

Abstract: An arrangement for projection copying of masks onto a workpiece, in particular onto a semiconductor substrate for producing integrated circuits, wherein the images of the patterns of the masks are formed by a projection lens on a photosensitive layer on the workpiece. The projection lens is completely corrected at the exposure wavelength used, and alignment patterns of the mask are aligned relative to adjustment marks on the workpiece, after images of the alignment pattern and the adjustment mark have been formed in the same plane, with adjustment exposure, by the projection lens and possibly an auxiliary optical means.

Abstract: In a method for the projection printing of masks onto a wafer coated with a photosensitive layer, said mask and said wafer being aligned by imaging alignment patterns of said mask onto said wafer by means of alignment light. In order to obtain a high-intensity and high-contrast alignment signal generated by plotting said alignment light reflected from said wafer, said alignment light comprises at least two narrow wavelength ranges spaced from each other on the wave length scale, in said ranges said photosensitive layer of said workpiece being non-sensitive or low-sensitive, determining the intensity of said alignment light reflected from said workpiece and generating an alignment signal from the wavelength range of said alignment light having highest intensity.

Abstract: A method and a device for controlling operating processes applied to particles. The device comprises a number of operating stations, such as, lifting- and sluing conveyors to allow for feeding the particles to an indexing rotary plate and conveying of particles to a processing stage, e.g. a welding device. The operating processes of the operating stations are initiated according to a common, pre-set cycle, at least one of the operating stations is associated with a correcting process initiated by a sensor arrangement for detecting faults in the operating process, for shortening the outages and for increasing the total output. The operating process involving a fault detected by the sensor arrangement is immediately interrupted, whereupon the correcting process is initiated independently of the common, pre-set cycle. The common, pre-set cycle serves to initiate dependent subsequent or previous operating processes of the operating stations until the end of the correcting process.

Abstract: A device for the projection printing of the masks of a mask set onto a semiconductor substrate comprising a projection lens for imaging the patterns of said masks on photosensitive layers of said substrate. Alignment patterns are disposed said masks and alignment targets on said substrate. Said alignment patterns of at least one of said masks and said alignment targets of said substrate are positioned in non-conjugated areas in respect of the projection lens, i.e. in areas which cannot be imaged into one another by means of said projection lens. For the alignment process between said mask and said substrate auxiliary optical means are provided, said alignment targets of said substrate and said alignment patterns of said mask being imaged into one another by means of said auxiliary optical means.

Abstract: A device for fixing a planar work piece in position, particularly a semiconductor used in processing cycles for the production of integrated circuits. Said device having a supporting plane, a number of apertures being disposed in said supporting plane, said apertures being under reduced pressure, said work piece being pressed against said supporting plane by means of said reduced pressure. Said device being particularly suitable for precisely fixing a semiconductor substrate in the supporting plane, even in the case of extensive raised areas or warps on the lower side of the substrate. A number of independent reduced pressure systems are provided, said reduced pressure systems being connected with individual apertures or groups of apertures.