Chemistry: electrical and wave energy – Apparatus – Electrolytic
Reexamination Certificate
2000-02-18
2002-10-29
Tung, T. (Department: 1743)
Chemistry: electrical and wave energy
Apparatus
Electrolytic
C204S416000
Reexamination Certificate
active
06471838
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to a measuring device for examining a medium, especially one that is liquid or free-flowing, and a process for manufacturing a measuring device of this type.
From PCT publication WO 95/31716 a measuring device is already known which has an electrically conducting layer located on a substrate layer and having two layer areas each arranged in the plane of the layer and electrically insulated from each other. The two layer areas form electrodes which have approximately the shape of a comb. The layer areas mesh into each other with their comb structures. This previously known measurement device has proven valuable in practice, especially for the physiological examination of biological cells which are arranged in a nutrient medium and adhere during measurement to the surface of the substrate layer and the planar conducting layer areas located on it. With this previously known measurement device, on the one hand, conductivity measurements can be performed on a cell membrane area of the cells located in the deposit area of the cells, and on the other hand, the measurement device also makes possible a capacitive uncoupling of electric signals from the cell membrane.
A disadvantage of this previously known measurement device, however, still exists in that it only allows an examination of the cells on the conductive layer areas and the underside of the cells which is facing the substrate layer. It has been revealed, however, that biological cells can have different electric and/or optical properties in various areas of their cell membrane which, for example, can be brought forth by a locally varying diffusion of ions or proteins located in the cell liquid of the cells.
SUMMARY OF THE INVENTION
Therefore, an object of the invention is to create a measurement device, of the type described above, which allows for further examination of the medium. In addition, an object of the invention is to provide a process for manufacturing such a measuring device.
This object is achieved in that the measuring device has at least two electrically and/or optically conducting layers or layer areas made of a solid material and located on a substrate layer, wherein these layers or layer areas are electrically and/or optically insulated from each other, in that at least one of these layers or layer areas is arranged in a layer stack, which has several layers arranged on top of each other on the substrate layer, in that the layer stack has, on its side facing away from the substrate layer, a recess that adjoins the electrically and/or optically conducting layers or layer areas; and in that at least one layer located in the layer stack, which is electrically and/or optically conducting, or the at least one layer area located in the layer stack, which is electrically and/or optically conducting, is spaced at a distance from the bottom of the recess.
The measuring device thus has a layer stack with-a recess, adjoined by at least one electrically and/or optically conducting layer or one layer area of the layer stack, which is set off at a distance from the bottom of the recess by at least one additional layer. Thus, on the limiting wall of the recess, an electrically conducting and/or optically transparent wall area is produced, which is arranged at a distance from the bottom of the recess. In this way, it is possible to emit electrical and/or optical signals into the medium located in the recess, or to receive them from the medium, at a position spaced from the bottom of the recess. In a measuring device which is electrically conducting at the layer or layer area adjacent to the recess and spaced from the bottom of the recess, conductivity measurements or capacitive measurements, for example, can be carried out, for example in a direction transverse to the extension plane of the substrate layer or in a direction running parallel to it, on the medium located in the recess and/or particles contained in it, for example biological cells which have settled on the bottom of the recess.
In a measuring device in which the layer or layer area spaced from the bottom of the recess and adjacent to the recess is optically transparent, it is even possible to measure the optical transmission or emission in the medium in a direction running transversely to the extension plane of the substrate layer or in a direction parallel to it. A transmission measurement can occur, for example, such that through one of the optically transparent layers or layer areas, an optical radiation is coupled into the recess and transmitted through the medium to the other optically transparent layer, and via this layer it is uncoupled again from the recess. The measurement device thus allows a three-dimensional investigation of a medium located in the recess.
In an advantageous way, with the electrically and/or optically conducting layer, which is spaced from the bottom of the recess in the limiting wall of the recess and oriented with its active surface transverse to the coating plane of the substrate layer, a compactly designed measurement device is produced, which requires only a comparatively small area on the substrate layer. In a measuring device constructed as a semiconductor chip, expensive chip area can thus be saved.
In one advantageous embodiment of the invention, at least one layer of the layer stack has at least two electrically and/or optically conducting layer areas arranged next to each other in the coating plane of this layer, each being adjacent to the recess and insulated from each other electrically and/or optically. The medium located in the recess can then be examined optically and/or electrically at a distance from the bottom of the recess in the coating plane of this layer. It is even possible herein that the layer have more than two layer areas, each adjacent on the sides of the recess and electrically and/or optically conducting, so that the medium located in the recess can then be examined in different directions in the coating plane of this layer, depending on between which of these layer areas in the recess, an optical and/or electrical measuring path is formed.
It is especially advantageous if, on each side of an optically conducting layer or layer area, a metallic layer or layer area is arranged transverse to the coating plane as an optical reflection layer. Radiation losses in the layers adjacent to the optically conducting layer are thereby reduced. The metallic. layers adjacent to the optical layer can optionally be adjacent to the recess, so that these layers also allow coupling and/or uncoupling of electric signals into the optically conducting layer outside of a guide for the optical radiation.
In one especially advantageous embodiment of the invention, on the limiting wall of the recess, at least one electric and/or optically conducting layer area forms a projection relative to at least one layer area adjacent to it, and the layer area having the projection and the layer area adjacent to it are preferably arranged in different coating planes of the layer stack. In an electric layer a small ohmic contact resistance then occurs between the layer and the medium located in the recess, while in an optically conducting layer the projection allows a small optical radiation resistance between the layer and the medium.
In one advantageous embodiment of the invention, the limiting wall of the recess has at least one coupling location, which is located on an optically conducting layer and/or on an optically conducting layer area, for the targeted emission of optical radiation into the recess. In the limiting wall, lying opposite the coupling position in the emission direction of the radiation, at least one uncoupling position is arranged on an optically transparent layer or layer area. The coupling position and/or the uncoupling position is (are) arranged on a projection which projects into the recess beyond the layers on both sides adjacent to it and can be extended against the restoring force of its material from a rest position transverse to the coating plane of the laye
Gahle Hans-Jürgen
Igel Günter
Lehmann Mirko
Akin Gump Strauss Hauer & Feld L.L.P.
Micronas GmbH
Noguerola Alex
Tung T.
LandOfFree
Measuring device and process for its manufacture does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Measuring device and process for its manufacture, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Measuring device and process for its manufacture will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2961427