Patent Number: 055352502
Section: summary

BACKGROUND OF THE INVENTION a) Field of the Invention The present invention is directed to a device for manipulating a bundle of synchrotron rays, in particular in irradiating apparatuses for deep X-ray lithography which contain within a vacuum chamber an object table for receiving an object to be irradiated, which object table is adjustable by means of a scanning movement relative to the synchrotron beam bundle entering the vacuum chamber via a window. b) Description of the Related Art Such irradiating devices can be used to fabricate microsystems components by means of a technique known as the LIGA process (lithography with synchrotron radiation, electroforming and plastics molding) (LIGA process, Microelectronic Engineering 4 (1986) 35-56). In this process, a resist layer is exposed directly by synchrotron radiation in the deep X-ray lithography process step by masking with an X-ray mask. To this end, the X-ray mask and the resist layer applied to the substrate are arranged on an object table which is adjustable in a scanning movement relative to the synchrotron beam bundle. The dimensions of the object table are typically approximately 100 mm in the horizontal direction and approximately 5 mm in the vertical direction. As a result of the action of radiation in the non-masked regions, the structure of the resist is changed in such a way that the exposed surfaces of the resist layer can be dissolved in a subsequent development process. Since the synchrotron beam bundle has substantially constant characteristics with respect to its dimensions and spectral properties, modifications are required for the multitude of different applications. These modifications must be carried out under vacuum conditions and may not have a disruptive influence on the exposure process itself. For example, overexposure at the reversal points of the scanning movement must be eliminated in particular. OBJECT AND SUMMARY OF THE INVENTION Therefore, a primary object of the present invention is to produce, under vacuum conditions, properties of the beam bundle which are adapted to the respective case of application for deep X-ray lithography, in particular which are adapted to the scanning regimen. In a device for manipulating a synchrotron beam bundle, in particular in irradiating apparatuses for deep X-ray lithography containing within a vacuum chamber an object table for receiving an object to be irradiated, which object table is adjustable by a scanning movement relative to the synchrotron beam bundle entering the vacuum chamber via a window, the proposed object is met according to the invention in that pairs of diaphragms which are displaceable relative to one another are provided between the object table and window adjacent to a filter chamber which is connected upstream of the vacuum chamber and contains filters which can be inserted into the synchrotron beam bundle, and the pair of diaphragms for which the direction of relative displacement of the diaphragms coincides with the scanning movement is coupled with the scanning movement. Filter changers are advantageously provided for inserting the filters into the synchrotron beam bundle, a pneumatic cylinder being fastened via stay rods to a vacuum flange which can be arranged on the filter chamber. The movement of the pneumatic cylinder is transmitted to a connecting rod by means of a rod linkage which extends into a guide bush and membrane bellows, a filter holder being fastened to the connecting rod. The filter holder can have two frame members which are provided with an elongated aperture adapted to the cross section of the synchrotron beam bundle. In an advantageous manner, one pair of diaphragms which are displaceable relative to one another forms a component part of a first beam limiting unit which limits the synchrotron beam bundle horizontally. For each of the diaphragms which are displaceable relative to one another, a guide rail is rigidly supported on a mounting plate and a spindle is rotatably supported on the mounting plate via holding elements, and a spindle nut which is fixed relative to rotation on the spindle carries one of the diaphragms. Sensors which are fastened to the mounting plate serve for positioning the diaphragms. The other pair of diaphragms which are displaceable relative to one another should form a component part of a second beam limiting unit which limits the synchrotron beam bundle vertically and in which the displacement of the diaphragms is carried out by driving members which substantially correspond to those driving the diaphragms and are fastened to the movable part of the object table. Apart from the selective spectral filtering, the device according to the invention at the same time realizes an edge limiting of the synchrotron beam bundle so as to rule out overexposure at the reversal points of the object table.