ARRANGEMENT WITH A MEMS DEVICE AND METHOD OF MANUFACTURING
An arrangement and a production method for the arrangement with at least one MEMS device, which comprises a package that closely encloses the MEMS device and seals it from ambient influences. The package comprises as sealing a PFPE layer of a perfluoropolyether polymerized with the aid of functional groups.
1 . Arrangement with at least one MEMS device,
comprising a package enclosing at least the MEMS device and sealing it from ambient influences,
in which the package comprises a PFPE layer of a perfluoropolyether polymerized with the aid of functional groups, the PFPE layer sealing the package from the ambient influences.
2 . Arrangement according to claim 1 , in which the PFPE layer is structured and covers part of the arrangement.
3 . Arrangement according to claim 1 ,
in which the MEMS device is arranged on a substrate, and
in which the PFPE layer covers the MEMS device over a large surface area, rests at least partially on the substrate, and seals the MEMS device with respect to the substrate.
4 . Arrangement according to claim 3 , in which the PFPE layer is applied to the MEMS device or to the substrate in a structured form and forms a sealing intermediate layer for a covering arranged thereover.
5 . Arrangement according to claim 4 , in which the covering comprises a plate or a platelet of a ceramic or crystalline material.
6 . Arrangement according to claim 4 , in which the MEMS device or the substrate comprises the same crystalline or ceramic material as the covering.
7 . Arrangement according to claim 1 , in which the PFPE layer is structured in the form of a frame and either (a) rests on a surface of the MEMS device and encloses the device structures thereof or (b) rests on a surface of the substrate and encloses at least the MEMS device, and
in which the covering rests with close contact on the PFPE layer structured in the form of a frame, so that a cavity is formed between the covering, the PFPE layer and the surface of the MEMS device or of the substrate.
8 . Arrangement according to claim 1 , in which the PFPE layer is structured and comprises at least a first and a second structured partial layer,
in which the second structured partial layer rests on a first partial layer and is chemically bonded to it, and
in which the first and second PFPE partial layers together form a three-dimensional structure.
9 . Arrangement according to claim 8 , in which the three-dimensional structure takes the form of a cap, defined in which is a recess that is open on one side, and in which the cap sits on the MEMS device or on the substrate in a sealing manner with respect to the surface thereof, so that the device structures or the MEMS device as a whole are arranged in the recess and protected from ambient influences.
10 . Arrangement according to claim 8 , in which the three-dimensional structure has on one side a multiplicity of recesses, in which a device or the device structures of an MEMS device is/are respectively arranged.
11 . Arrangement according to claim 1 , in which the PFPE layer is applied over a large surface area as a sealing layer over a MEMS device mounted on the substrate by the flip-chip technique.
12 . Arrangement according to claim 1 , in which further devices are provided on the substrate and at least one of these devices is sealed with the aid of a large-area or structured PFPE layer.
13 . Arrangement according to claim 1 ,
in which the PFPE layer covers the MEMS device or device structures thereof, and
in which a further covering layer is applied directly over the PFPE layer for sealing or shielding purposes.
14 . Arrangement according to claim 13 , in which the further covering layer is a metal layer or a dielectric layer deposited from the vapour phase.
15 . Arrangement according to claim 1 , in which the MEMS device is a micro-structured electromechanical device with a movable part, a sensor or a device operating with acoustic waves.
16 . Arrangement according to claim 1 , in which the MEMS device is an RF device.
17 . Arrangement according to claim 1 , in which the functional groups of the PFPE layer are crosslinked methacrylate groups.
18 . Method of manufacturing an arrangement with a MEMS device, the method comprising
depositing a covering layer or an interface layer of a PFPE layer onto the arrangement with the MEMS device, the PFPE layer comprising a perfluoropolyether bearing cross-linkable groups, and a photoinitiator, and
cross-linking the PFPE layer by irradiation.
19 . The method of claim 18 , wherein the cross-linking is done in a structured way by a photomask or a scanning exposure to light.
20 . The method of claim 18 , wherein
the PFPE layer is first arranged on an intermediate carrier and pre-cross-linked up to a first stage comprising a pre-cross-linked PFPE layer, and
the pre-cross-linked PFPE layer is separated from the intermediate carrier, transferred to the arrangement with the MEMS device and there, finally, completely cross-linked.