Device and method for aligning substrates

#This invention relates to a method for aligning and bringing a first substrate into contact with a second substrate and a device for performing the same.

#The miniaturization of electronic circuits, such as, for example, microchips or storage structural units as well as micromechanical components and microfluid components, has been continuously advancing for decades. In order to further increase the density of these functional groups, stacking of such devices was begun some years ago. The functional groups are produced for this purpose on a substrate, for example a wafer. The wafers are then aligned with one another and bonded with one another, which in some few process steps leads to a large yield and primarily functional groups stacked on one another in a high density.

#The functional groups of different wafers in most cases also have different functionalities. Thus, the functional groups of a first wafer can be microchips, while the functional groups of the second wafer can be memory chips. Before the actual connecting process, an alignment of the wafers with one another is carried out. The smaller the functional groups on the wafers, the more precise the alignment process of two wafers with one another must be in order to achieve the necessary precision and a correspondingly low scrapping.

#FIG. 1a is a diagrammatic cross-sectional visualization of a device according to the invention in a first embodiment,

#FIG. 1b is a diagrammatic cross-sectional visualization of the device according to the invention in a second embodiment,

#FIG. 1c is a diagrammatic cross-sectional visualization of the device according to the invention in a third embodiment,

#In the figures, advantages and features of the invention are characterized with these reference numbers to be identified in each case according to embodiments of the invention, whereby components or features with functions that are the same or that have the same effect are characterized with identical reference numbers.

#FIGS. 1a-1c show respectively diagrammatic cross-sections of three embodiments of alignment units 1, 1′, 1″ comprised of: A first detection unit 3 in the form of a left upper optics or with a left upper optics. A second detection unit 3′ in the form of a left lower optics or with a left lower optics, as well as Another first detection unit 3″ in the form of a right upper optics or with a right upper optics, and Another second detection unit 3′″ in the form of one right lower optics or with one right lower optics, A first holder 4 in the form of an upper holder or with an upper holder, as well as A second holder 5 in the form of a lower holder 5 or with a lower holder 5.

#The first detection units 3, 3″ are able to move in all three directions in space X, Y and Z due to an X-translational unit 8, a Y-translational unit 9, and a Z-translational unit 10. In special embodiments, it would also still be conceivable that rotational units are incorporated, which allows a rotation of the optical axis around three axes that are orthogonal to one another. In a special embodiment, the actual optics would then be mounted on, by way of example and not limitation, a goniometer. In order to simplify the visualization, these rotational units are not depicted in the drawings.