Joints and connections – Molded joint – Socket or open cup for bonding material
Reexamination Certificate
1998-12-11
2001-05-08
Kim, Harry C. (Department: 3629)
Joints and connections
Molded joint
Socket or open cup for bonding material
C403S024000, C403S292000, C403S404000
Reexamination Certificate
active
06227754
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to a composite body which is made by joining at least two bodies together. The first body consists of a first material and the second body consists of a second material. Each of the two bodies has at least one connecting surface and the connecting surfaces lie opposite each other. Both connecting bodies are joined to each other by at least one adhesive connection.
BACKGROUND OF THE INVENTION
For certain applications, the body to be produced should have only minimal deformations after the assembly (the permissible range of deformation lies in the nanometer range). These applications include the production of larger bodies made of several individual bodies. The minimal deformations are preferably at the mirrored surfaces, measurement surfaces or support surfaces for other components. Not only is the size of the body to be produced relevant, but especially its form, such as inner edges. The application of these bodies is preferably in areas wherein nanometers are a relevant size such as in microscopy, astronomy, et cetera.
Essentially two methods are known in the state of the art of fine assembly technology for joining two bodies tightly to each other. These methods are presented as (a) and (b) below.
(a) When bodies are wrung to each other, optical surfaces are joined to each other via the van der Waal forces. Wringing is primarily used for force-tight temporary connections in manufacture. It is a disadvantage in this method that the two bodies joined by wringing easily separate because of liquids which wet the connecting edges. Wringing is also not necessarily resistant to vibration.
In production, wringing is used as a permanent connection for small optical elements having dimensions in the millimeter range. Large elements having dimensions in the centimeter range cannot be joined in this manner with the reliability required for a permanent connection.
Wringing can be improved and be made more reliable by means of a holding lacquer and/or an adhesive material outside of the wringing surfaces in order to increase the durability of the connection. However, the connection cannot be perfected.
(b) When applying adhesive in the absence of tension, the adhesive locations are usually optimized by a clever configuration of the adhesive locations (optimization of the adhesive gap and the adhesive pads). With this optimization, basic requirements (adhesive gap 1/10 mm, pads 6×6 mm) are considered in accordance with the state of the art.
Glued parts have the significant disadvantage that a force-tight and form-tight connection is not necessarily possible. The unavoidable creeping of the connection and the maladjustment of the parts to each other caused thereby likewise generates corresponding problems in some applications.
U.S. Pat. No. 4,826,303 discloses an arrangement for connecting at least two bodies with the bodies being connected to each other via a wedge-shaped connecting member without thermal constraining forces occurring. This arrangement has the disadvantage that both bodies have to be reworked after being joined because the wedge-shaped connecting member generates intense forces at the connecting surfaces. On the other hand, this connection is very stable.
German patent publication 3,934,546 shows an arrangement for adhesive-connecting two bodies by means of an intermediate piece. The intermediate piece is placed up to the surfaces of the two bodies and the surface cannot be used in those regions.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a connection between larger bodies and especially bodies having low thermal coefficients of expansion (such as silicate, ceramic, Invar and the like). It is a further object of the invention to develop such a connection which is adequately satisfactory for processes and is force-tight as well as satisfies tolerance requirements in the nm range.
In the composite body of the invention, a compensating element is used and arranged in the two bodies to be attached, that is, this compensating element is enclosed in the interior of and surrounded by both bodies. The compensating element is a feature of the invention that makes possible a partial to total decoupling of the adhesive shrinkage without this adhesive shrinkage becoming manifest in a disturbing manner at the exterior.
With this compensating body, only very slight to no measurable deformations of the compensating composite body occur. A judicious form of the adhesive location as well as a judicious selection of the arrangement of the adhesive position within the connecting surfaces support the advantageous effects of the compensating body.
With the new connection, it is possible to form-tightly and force-tightly connect optical elements to each other, which have large dimensions, that is, dimensions greater than 10 cm. Experiments have been made wherein the surfaces to be joined had a longitudinal extent of more than 40 cm. The creeping of the adhesive is no longer a consideration. The necessary strength is ensured by the adhesive locations.
Utilization of the invention is suitable especially in optical apparatus operating with low wavelengths because of the slight deformations of the composite body caused by the adhesive connection. As an example, a positioning table is mentioned (with movements in the X, Y axes and sometimes also along the Z axis) as is needed especially in UV microscopy. In a preferred embodiment, such a device is part of a wafer chuck of a wafer stepper or a wafer scanner.
In this context, all bodies used including the compensating body should be made of one and the same material in order to avoid thermal stresses.
REFERENCES:
patent: 4320984 (1982-03-01), Mayer et al.
patent: 4518446 (1985-05-01), Drennan
patent: 4721541 (1988-01-01), Hodges
patent: 4752151 (1988-06-01), Ashida et al.
patent: 4826303 (1989-05-01), Meier
patent: 5033904 (1991-07-01), Challis
patent: 5037234 (1991-08-01), De Jong
patent: 5660492 (1997-08-01), Bathon
patent: 5669997 (1997-09-01), Robbert et al.
patent: 2646351 (1977-12-01), None
patent: 3711466 (1988-10-01), None
patent: 274856 (1990-01-01), None
patent: 3934546 (1991-04-01), None
patent: 0119975 (1984-09-01), None
patent: 0651101 (1995-05-01), None
patent: 1534224 (1990-01-01), None
“Direct Bonding: From an Optical Technology to a Broad Research Topic”, Philips Journal of Research, NL, Elsevier, Amsterdam, Vol. 49, No. 1/02, pp.1-10.
Trier Bernhard
Trunz Michael
von Nessen-Lapp Kerstin
Carl-Zeiss-Stiftung
Kim Harry C.
Ottesen Walter
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