Abstract:
A chip and a method for producing the chip with a plurality of measurement regions which are provided with electrodes for electrically detecting reactions in which, in order to reliably separate the individual measurement regions from one another, a monolayer of a fluorosilane is formed on the chip surface which has strongly hydrophobic properties. Therefore, during spotting with a liquid, the drops of liquid applied by spotting can be reliably prevented from coalescing, and thus, causing mixing of the substances in the drops of liquid which are supposed to be immobilized in the measurement regions.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a division of commonly owned, co-pending U.S. patent application Ser. No. 14/894,421, filed Nov. 27, 2015, which is a §371 of PCT/EP2014/001462 filed May 30, 2014 claiming priority of DE 10 2013 210 138.4 filed May 30, 2013. 
     
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0002]    The invention relates to a method for producing a plurality of measurement regions on a chip, wherein electrically contactable electrode pairs are structured on the chip in each of the measurement regions and wherein the measurement regions are formed by producing a compartmental structure which separates the measurement regions from one another. 
       Description of Related Art 
       [0003]    Moreover, the invention relates to a chip having a plurality of electrically addressable measurement regions, wherein a compartmental structure which separates the measurement regions from one another is provided on the surface of the chip. 
         [0004]    A chip of the kind described hereinbefore and a method of producing it is known, for example, from U.S. Patent Application Publication 2009/0131278 A1. The chip is a silicon-based chip on the surface of which are provided a plurality of electrode pairs by metalizing and structuring. These pairings are in a two-dimensional array, preferably a chessboard arrangement. The electrode arrangements consist of electrode strips meshing with one another which ensure that the two electrodes of the electrode arrangement are adjacent to one another over a long distance. 
         [0005]    The measurement regions are provided for functionalizing with certain biologically active substances. These may be, for example, antibodies which react chemically to specific antigens, these chemical reactions being electrically detectable by means of the electrode arrangement. Functionalization is carried out by a so-called spotting process, in which each measurement region is acted upon by another, e.g., water-based solution. The molecules responsible for the functionalization on the corresponding measurement regions are thereby immobilized. It is crucially important that the different liquids in the individual measurement regions are not mixed with one another, to ensure that only one type of relevant molecules is present on each measurement region. 
         [0006]    To prevent the liquids of adjacent spots from being mixed together, it is proposed according to from U.S. Patent Application Publication 2009/0131278 A1 that mechanical barriers in the form of small walls may be provided between the individual measurement regions. The surface of the chip is thus divided into different compartments of a box, so to speak, the liquids each being “poured” into one of these compartments during the spotting process. However, it should be taken into consideration that the compartments present on the chip surface are of an order of magnitude in the μm range. Therefore, the effect of the mechanical boundaries comes up against its limits. As a result of the surface tension of the solvent, such as water, it may happen that in spite of the mechanical boundaries the liquids of adjacent measurement regions combine and thus the relevant functional molecules are mixed together. 
       SUMMARY OF THE INVENTION 
       [0007]    The object of the invention is to provide a method for producing a plurality of measurement regions on a chip, as well as a chip which can be produced by this method in particular, while at least substantially preventing liquids from mixing together during the spotting process. 
         [0008]    The above problem is solved by a method and a chip as described herein. 
         [0009]    It goes without saying that features, embodiments, advantages and the like which are mentioned hereinafter only in connection with one aspect of the invention, to avoid repetition, nevertheless also apply accordingly to the other aspects of the invention. 
         [0010]    It also goes without saying that in the statements of values, numbers and ranges provided hereinafter, the values or ranges specified should not be interpreted in a restrictive capacity; the skilled man will understand that deviations may occur from the specified ranges and figures, as a result of individual cases or in relation to particular applications, without departing from the scope of the present invention. 
         [0011]    Moreover, it is the case that all the values or parameters or the like specified hereinafter may be determined or ascertained by standardized or explicitly stated methods of determination or by methods of determination which are familiar to the skilled man. Subject to this, the present invention will now be described in more detail. 
         [0012]    According to one aspect of the present invention, the formation of the compartmental structure is preferably carried out using the following process steps. First, hydrophilic properties are produced in the measurement regions. This is a necessary prerequisite for wetting the measurement regions with a hydrophilic liquid. Generally, the functional molecules are dissolved in water, and for this reason the hydrophilic properties of the measurement regions are of supreme importance. Moreover, the method according to the invention comprises producing hydrophobic wetting properties on the surface of the chip outside the measurement regions by applying a self-organized monolayer consisting of a fluorosilane compound. Examples of possible fluorosilane compounds include Teflon (polytetrafluoroethylene or PTFE). For example, (tridecafluoro-1,1,2,2-tetrahydrooctyl) trichlorosilane C8H4Cl3F13Si may be used. Advantageously, the hydrophobic effect of this monolayer is far more effective than a mechanical barrier. Owing to the fact that the chip surface between the measurement regions is virtually impossible to wet with hydrophilic liquids, a safety interval is produced between the individual spots of the functional liquids, which effectively prevents mixing. Therefore, reliably functionalized chips can advantageously be produced by the method according to the invention. 
         [0013]    According to another aspect of the present invention, in particular, a chip is proposed in which the compartmental structure is formed from a self-organized (self-assembling) monolayer, consisting of a fluorosilane compound, which covers the chip surface outside the measurement regions. 
         [0014]    A monolayer is formed when only one layer of molecules is formed on the chip surface. The self assembly of the monolayer is caused by the structure of the fluorosilane compound used. The fluorosilane molecules comprise a trichlorosilane group which has a high affinity for silicon, which is why this group is provided on the surface of the chip. The remainder of the molecules are then distanced from the surface, and form a surface which is comparatively hydrophobic. This hydrophobic action on the surface is advantageously highly effective. 
         [0015]    According to an embodiment of the method according to the invention, the method is carried out using the following steps in the order specified, in order to form the compartmental structure. First, a fluorosilane compound is vapor-deposited on the chip surface as a monolayer. This takes place in a vacuum atmosphere. CVD or PVD processes may be used. Then a photo-structurable coating is applied to the chip surface. This initially covers the whole of the chip surface. Next, the measurement regions are illuminated through a suitable mask. By developing the photo-structurable coating, a photo-structured coating is formed in which the measurement regions can be exposed. In the measurement regions thus exposed, hydrophilic properties are generated so that the aqueous solutions can be spotted onto them. Finally, the photo-structurable coating is removed. 
         [0016]    According to an alternative embodiment of the invention, the method for forming the compartmental structure may also be carried out using the following process steps in the order specified. First the hydrophilic properties are generated over the entire chip surface. Then a photo-structurable coating is applied to the chip surface. This can be photo-structured by illuminating the surface of the chip outside the measurement regions. A photo-structured coating is produced by developing the photo-structurable coating, the measurement regions being covered by the photo-structured coating. Then a fluorosilane compounds is vapour-deposited in a monolayer on the surface of the chip, in the manner already mentioned. Finally, the photo-structured coating is removed. 
         [0017]    The two alternative processes have the major advantage that the individual production steps are well known per se and can therefore be carried out with considerable process reliability. Therefore, by improving the process reliability, high quality results are advantageously obtained. 
         [0018]    According to another embodiment of the process, it is provided that the production of the hydrophilic properties is carried out in an oxygen plasma or by dry etching. These methods, which are conventional in the processing of wafers, are also advantageously carried out with high process reliability. 
         [0019]    According to a further embodiment of the invention it is provided that, after the end of the process steps as described above, the processed chip surface is cleaned. In this way the chip surface can be prepared for a subsequent spotting process. Contamination is advantageously eliminated so that after spotting no measurement errors occur as a result of a contaminated surface of the measurement regions. The cleaning of the processed chip surface may form the end of the preparation of the chips. These chips are then packaged so that no further cleaning of the chip surface is required. The user will then only remove the packaging just before the spotting process is carried out. Alternatively, it is, or course, also possible for the cleaning to be carried out by the user at the last possible moment before the spotting process. 
         [0020]    The cleaning is preferably carried out by a wet chemical method. The use of a piranha solution is recommended. This consists of a mixture of hydrogen peroxide and sulphuric acid and constitutes a highly effective compound for cleaning the surface. Advantageously, the monolayer of fluorosilane compounds is sufficiently chemically stable to withstand this cleaning step. 
         [0021]    According to a further embodiment of the invention it is also possible for the functionalization of the measurement regions by a spotting process to be carried out immediately after the cleaning has taken place. In this case the user is provided with the already functionalized chips. This is advantageous in analytical processes which are very often used as standard, as the chips can be functionalized in large numbers immediately after manufacture. This satisfactorily prevents contamination during the process. 
         [0022]    According to another aspect of the present invention, a method for producing a chip having a plurality of electrically addressable measurement regions or for producing a plurality of measurement regions on a chip is proposed, in which electrically contactable electrode pairings are structured in each of the measurement regions on the chip and the measurement regions are formed by producing a compartmental structure which separates the measurement regions from one another. 
         [0023]    The formation of the compartmental structure comprises the production of hydrophobic wetting properties on the surface of the chip outside the measurement regions. Moreover, the formation of the compartmental structure may include the production of hydrophilic properties in the measurement regions. 
         [0024]    Furthermore, according to an aspect of the present invention which can be achieved independently, the measurement regions are provided with a protective coating at least substantially until the chip is incorporated in an electric component. By the expression “until the chip is incorporated” is meant the process step in the manufacture of the chip in which removal of the protective coating makes sense. This may be immediately before the spotting process, but may also, for example, be immediately after the cutting of the wafer from which the chip is made, or after the electrical contacting (bonding) of the (individual) chip. 
         [0025]    The use of a protective coating which at least substantially covers the measurement regions makes further processing of the chip easier. The chip, or the wafer from which the chip is made, may for example be divided up or electrically connected or provided with passivation on the outside or cast, without any risk of the delicate measurement regions or areas of the chip vapor-coated with metals such as gold, being exposed to mechanical, thermal or chemical stresses and being damaged or even destroyed. 
         [0026]    Within the scope of the present invention, particularly good results are obtained if the protective coating is a photo-structured coating or a photoresist. Photo-structured coatings are generally obtainable from photo-structurable coatings. By a photo-structurable coating is meant, within the scope of the present invention, a coating the aggregate state and/or chemical nature of which is altered by the effects of electromagnetic radiation, particularly UV radiation, thus producing a photo-structured coating. In particular, it is provided in this context that only the regions of the photo-structurable coating which are exposed to the electromagnetic radiation are subject to change. The change in the protective coating induced by the effect of electromagnetic radiation may be in particular such that the coating becomes fixed or liquefies, is chemically cured, i.e. cross-linked, or polymeric structures are destroyed. Thus, by the use of masks and UV radiators, for example, structures can thus be produced on the surface of the chip. 
         [0027]    In this context it may be envisaged that the photo-structured coating contains a photoresist or is a photoresist. Photoresists which usually cure under the effect of UV radiation are known per se to the skilled man and are commercially available in large numbers. 
         [0028]    Within the scope of the present invention it is preferable if the photo-structured coating is a photoresist which is also used within the scope of rendering the chip surface hydrophobic. In this way, time, materials and equipment can be saved within the scope of the present invention, as the photo-structured coating applied in the course of producing the hydrophobic finish, particularly the photoresist, also remains on the measurement regions for protecting the measurement regions even after the hydrophobic finish has been applied and continues to protect these regions up to the time of installation or until the processing of the chip has been complete. 
         [0029]    If a photo-structured coating is used as a protective coating for the within the scope of the present invention, it is preferable if the photo-structured coating, particularly the photoresist, is chemically and/or physically stable at least for short periods at temperatures up to 150° C., particularly 200° C., preferably 250° C., preferably 300° C. During the processing of the chip, for example during the cutting process or installation into devices, it may happen over and over again that the chip is subjected to thermal peaks, i.e. short-lived thermal stresses. In this case, the photo-structured coating or the photoresist must not decompose chemically, nor can the chemical or physical nature change so that the measurement regions are no longer adequately protected, or the coating is no longer removable at a later stage. 
         [0030]    For this reason, the protective coating or the photo-structured coating applied should be sufficiently thermally stable, particularly at the temperature peaks which occur briefly during the processing of the chip. 
         [0031]    Thermally resistant photo-structured coatings or photoresists of this kind are advantageously formed on the basis of polyamide, within the scope of the present invention. Polyamide-based photoresists often have a decidedly high thermal stability of up to 400° C. and may furthermore be hydrophobic. 
         [0032]    Generally, the hydrophobic treatment is carried out within the scope of the present invention by applying a hydrophobic coating to the chip. In this context, it may be that the hydrophobic coating is applied to the chip in the form of a layer of lacquer or a monolayer. If the hydrophobic coating is applied as a layer of lacquer, this may refer particularly to photo-structured coatings, particularly photoresists, which cure or depolymerise or are destroyed by electromagnetic radiation, particularly UV radiation. When, within the scope of the present invention, the hydrophobic coating is formed by a photoresist, and in particular the photoresist is applied to the chip by one of the methods described above, there is no need for any further hydrophobic treatment of the surface of the chip. In this case, the hydrophobic photoresist remains outside the measurement regions on the chip and is not removed again. If, on the other hand, the hydrophobic coating is formed by a monolayer, it has proved satisfactory within the scope of the present invention if the monolayer is applied as a self-assembling monolayer. Monolayers produce particularly sharply delimited hydrophobic regions on the chip. 
         [0033]    Similarly within the scope of the present invention it may also be provided that the hydrophobic treatment is carried out by reacting with reactive chemical compounds. Preferably, the reactive chemical compounds used within the scope of the present invention are silanes, particularly alkylsilanes and/or fluorosilanes. When alkylsilanes are used within the scope of the present invention, it has proved suitable to use trialkylsilanes or silazanes as alkylsilanes, preferably trimethylchlorosilane and/or hexamethyldisilazane. If, on the other hand, fluorosilanes are used within the scope of the present invention, it has proved satisfactory to use partially fluorinated or perfluorinated silanes, most preferably tridecafluoro-1,1,2,2-tetrahydrooctyl-trichlorosilane. 
         [0034]    The use of fluorosilanes is particularly preferred as they have not only outstanding hydrophobic properties but also excellent chemical resistance. 
         [0035]    For further details on the process according to the invention, reference may be made to the foregoing remarks on the other aspects of the invention which apply equally to the method according to the invention. 
         [0036]    In respect of other details regarding the method according to the invention, reference may be made to the remarks concerning the other aspects of the invention which apply equally to the method according to the invention. 
         [0037]    Finally, according to a fourth aspect of the present invention, the invention also relates to a chip having a plurality of measurement regions, which can be obtained by the method described hereinbefore. 
         [0038]    For further details on the chip according to the invention, reference may be made to the foregoing remarks on the other aspects of the invention which apply equally to the chip according to the invention. 
         [0039]    Further details of the invention are described hereinafter by reference to the drawings. Identical or corresponding elements of the drawings have been given the same reference numerals in the figures and their explanations are only repeated where there are differences between the individual figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0040]      FIGS. 1 to 4  show selected steps of a first embodiment of the method according to the invention, 
           [0041]      FIGS. 5 to 7  show selected manufacturing steps of another embodiment of the method according to the invention, 
           [0042]      FIG. 8  shows a detail of the surface of the chip of an embodiment of the chip according to the invention as a three-dimensional view, and 
           [0043]      FIG. 9  shows a schematic representation of the chip in the connected and installed state. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0044]      FIG. 1  shows the detail of a chip  11  made of silicon. However, the chip  11  may also be made of a different material. 
         [0045]    Particularly preferably, the chip  11  comprises or contains electronic circuits and/or electrode arrangements  23  not shown in  FIG. 1  (cf.  FIGS. 8 and 9 ). 
         [0046]    The chip  1  preferably has a hydrophobic coating  12  which may take the form of a monolayer and/or may preferably contain or be formed from a fluorosilane compound. 
         [0047]    Preferably, a fluorosilane compound, particularly as described above, has first been vapour deposited on the chip  11  in a desiccator, in the course of which the fluorosilane compound has formed a self-assembled monolayer  12  on the chip surface  13 . After this, a photo-structurable coating  14  has been applied to the monolayer  12 . Using a perforated mask  15 , the regions that are intended to form the measurement regions  16  subsequently are illuminated with light  17  (cf. also  FIG. 4 ). 
         [0048]      FIG. 2  shows the photo-structured coating  18  after the photo-structurable coating  14  has been developed. In this way, the hydrophilic regions which subsequently produce the measurement regions  16  are defined. They appear as windows  19  in the photo-structured coating  18 . 
         [0049]      FIG. 3  shows how the hydrophilic regions have been produced in the oxygen plasma. The monolayer  12  has been removed in the region of the windows  19 , apart from the chip surface  13 . In this way the hydrophilic measurement regions  16  are formed. Then the photo-structured coating  18  has also to be removed from the monolayer  12 . This can be seen in  FIG. 4 .  FIG. 4  also shows how different liquids  20   a,    20   b  are applied to the measurement regions  16  in order to functionalize these measurement regions (spotting method). In this way the finished functionalized chip  11  is produced. 
         [0050]    The method according to  FIGS. 5 to 7  also works with a photo-structurable coating  14  and a hydrophobic coating or a monolayer  12  (cf.  FIG. 6 ). However, the order of application of these two coatings is precisely reversed, compared with the method described according to  FIGS. 1 to 4 . According to  FIG. 5 , first of all, the photo-structurable coating  14  is applied to the surface  13  of the chip  11 . 
         [0051]    For structuring the photo-structurable coating  14 , an illuminating mask  21  is preferably used which consists of a transparent sheet and has a lightproof coating  22  in the region of what will subsequently be the measurement regions  16 . The photo-structurable coating  14  is structured by means of the light  17 . 
         [0052]    As can be seen from  FIG. 6 , the photo-structured coating  18  remains in the measurement regions  16 , while the surrounding areas have been exposed right down to the surface of the chip  13 . These regions are then coated with the hydrophobic coating or self-assembling monolayer  12 , particularly of fluorosilanes. 
         [0053]    As can be seen from  FIG. 7 , the photo-structured coating  18  is then removed, exposing the measurement regions  16 . These are located directly on the chip surface  13 . The functionalizing of the measurement regions  16 , as described previously, is carried out by a spotting process in which the liquids  20   a,    20   b  are applied. 
         [0054]    Alternatively, the measurement regions  16  may also only be exposed later. The measurement regions  16  are then protected by the photo-structurable coating  14  or the photo-structured coating  18 , i.e., by a protecting coating, or by a photoresist or the like which forms it, for example, until the chip  11  has been separated from other chips (not shown) of a wafer or the like, and/or until the chip  11  has been electrically connected (bonded) and/or provided with a passivation layer on the outside and/or cast into position or installed in a housing. 
         [0055]    To form the photo-structurable coating  14  it is particularly preferable to use a photoresist. Particularly preferably, a polyamide-based photoresist is used, especially on account of its thermal stability. 
         [0056]    According to another alternative, the structurable or structured coating  14 ,  18  or the photoresist is preferably used instead of the monolayer  12  or fluorosilane compound to form the hydrophobic layer  12  or compartmental structure  24 . The photo-structurable coating  14 , as indicated in  FIG. 5 , then forms the hydrophobic layer or coating in the desired regions and hence the compartmental structure  24  or intermediate regions  27 . The method is thereby simplified, as preferably only the coating  14  or the photoresist has to be removed to form the measurement regions  16 , i.e. there is no need to apply a second coating. In this case the photoresist is then preferably of a correspondingly hydrophobic nature or can be rendered hydrophobic by an alternative method. 
         [0057]      FIG. 8  shows a detail of the edge of a measurement region  16  on the chip surface  13 . The measurement region  16  comprises an electrode pairing or arrangement  23  which preferably consists of a first electrode  23   a  and a second electrode  23   b.  These electrodes preferably comprise fingers which preferably mesh with one another. This electrode arrangement  23  reacts with great sensitivity to the fact that functional molecules (not shown in detail) which are immobilized in the measurement region  16 , react with molecules that are to be detected. 
         [0058]    The measurement region  16  is also surrounded by a compartmental structure  24 , only a detail of which is shown. Part of this detail is shown on a larger scale, showing that the compartmental structure  24  is preferably formed from the layer or monolayer  12 . This consists particularly of molecules of the fluorosilane compound, these molecules being docked with their functional group  25  on the surface  13  of the chip  11 , whereas the molecular residue  26  which produces the highly hydrophobic properties of the monolayer  12  projects upwardly or away from it. 
         [0059]    Preferably, the compartmental structure  24  or the hydrophobic coating  12 —particularly on its free surface—forms a hydrophobic intermediate region  27  between the (adjacent) measurement regions  16 , so that liquids  20   a,    20   b  not shown in  FIG. 8  do not flow into adjacent measurement regions  16  or mix or combine fluidically with adjacent liquids during spotting, i.e. during the application of drops of liquid to the measurement regions  16 , particularly for immobilizing scavenger molecules or the like (not shown). 
         [0060]    The compartmental structure  24  or the hydrophobic coating  12  or the respective intermediate region  27  is therefore preferably hydrophobic, particularly strongly hydrophobic. 
         [0061]    Particularly preferably, the contact angle of the compartmental structure  24  or the hydrophobic coating  12  or the intermediate regions  27  with water is at least substantially 90°, preferably more than 120°, most preferably more than 150°, in each case measured under normal conditions with distilled water. 
         [0062]      FIG. 9  shows, in a highly diagrammatic plan view, the proposed chip  11  in the connected, installed state, or the chip  11  with or in a housing  28 . 
         [0063]    Preferably, the chip  11  together with other chips  11  is produced in a conventional process, for example by the CMOS method, on a common carrier or substrate, particularly a so-called wafer. Then the chips  11  are separated from one another, connected electrically and preferably installed, particularly in an associated housing  28  or the like. 
         [0064]    In the embodiment shown, the chip  11  is preferably electrically connected to contact surfaces or terminals  29 , particularly by electrical connections  30  indicated by dashed lines. This is only schematically shown here. The electrical connection of the chips  11  is usually referred to as bonding. 
         [0065]    In the installed state, at least the measurement regions  16  are accessible for receiving samples (not shown) that are to be measured. 
         [0066]      FIG. 9  shows the compartmental structure  24  which with its intermediate regions  27  or hydrophobic layers  12  (completely) surrounds the measurement regions  16  and/or separates them from one another. In particular, a lattice-like or honeycomb-shaped structure is formed, each measurement region  16  preferably being annularly defined. 
         [0067]    As already mentioned, the measurement regions  16  may be covered or protected by a protective layer, particularly a coating  14 , particularly preferably of photoresist. This protective coating is then preferably not removed until after the cutting or division of the chips  11  and/or after the electrical connection and/or installation of the chip  11  in question. However, it is also possible to expose the measurement regions  16  earlier. 
         [0068]    If the removal of the protective layer does not take place until after installation, the protective layer is particularly preferably configured to be of sufficient thermal stability. In fact, for installation, the chip  11  is cast into position, in particular. Because of the temperatures occurring, a conventional photoresist may harden. This would at least make it difficult, if not completely impossible, to remove it from the measurement regions  16  at a later stage. Therefore, preferably, a photoresist is used which is sufficiently thermally stable without hardening. A polyamide-based photoresist is particularly suitable for this purpose. 
         [0069]      FIG. 9  schematically shows an electrode arrangement  23  in only one measurement region  16 , namely in the lower right-hand measurement region  16 . In particular, electrode arrangements  23  of this kind which are preferably identical or similar, are formed or arranged in all the measurement regions  16 . 
         [0070]    The electrode arrangements  23  are preferably formed before the production or application of the compartmental structure  24 . 
         [0071]    The electrode arrangements  23  are preferably located at least substantially in the chip surface  13  on which the measurement regions  16  are formed and the compartmental structure  24  is created. 
         [0072]    The chip surface  13  is preferably configured to be at least substantially flat and/or preferably constitutes a flat side of the chip  11 . 
         [0073]    In the embodiment shown, the hydrophobic layers  12  or intermediate regions  27  preferably adhere to one another and/or form a cohesive lattice. However, they may also form separate regions or portions on the chip surface  13  which surround or enclose one or more measurement regions  16 . 
         [0074]    Preferably, different molecules for detection may be detected in the measurement regions  16  by means of the electrode arrangements  23 . Corresponding detection signals are emitted electrically, in particular, by the chip  11  or can preferably be interrogated electrically. 
         [0075]    Preferably, the compartmental structure  24  is raised relative to the at least substantially flat ship surface  13 . 
         [0076]    Preferably, the compartmental structure  24  surrounds each measurement region  16  completely or annularly with the hydrophobic layer  12  of the hydrophobic intermediate region  27 . 
         [0077]    In particular, the compartmental structure  24  or hydrophobic layer  12  or monolayer or the intermediate region  27  is of lattice-like or honeycomb-shaped configuration. 
         [0078]    The compartmental structure  24  or hydrophobic layer  12  or intermediate regions  27  is or are preferably embodied as a flat and/or planar coating. 
         [0079]    Preferably, the compartmental structure  24  or hydrophobic layer  12  or the intermediate region  27  is smaller in height than width. Particularly preferably, the width between two adjacent measurement regions  16  is greater than the height relative to the chip surface  13  carrying the measurement regions  16  by a factor of at least 5, preferably by a factor of at least 10. 
         [0080]    Particularly preferably, the height of the compartmental structure  24  or hydrophobic layer  12  or the hydrophobic intermediate region  27  is less than 2 μm, more particularly less than 1 μm, and/or more than 10 nm, particularly more than 100 nm. 
         [0081]    Particularly preferably, the intermediate regions  27  have a width between the measurement regions  16  of more than 10%, particularly more than 20%, particularly preferably about 50% or more, of a measurement region  16 . 
         [0082]    Particularly preferably, the intermediate regions  27  have a width between the measurement regions  16  of more than 5 μm, particularly more than 10 μm or 20 μm, particularly preferably more than 50 μm. 
         [0083]    The measurement regions  16  preferably have a width or an average diameter of more than 50 μm, particularly more than 100 μm, and/or less than 500 μm, preferably less than 300 μm, particularly less than 200 μm, most particularly preferably about 120 to 180 μm. 
         [0084]    Preferably, during the so-called spotting, drops of liquid  20   a,    20   b  are applied to the individual measurement regions  16 , particularly each having a volume of 1,000 to 2,000 μl, while the hydrophobic layers  12  or intermediate regions  27  ensure that the drops of liquid  20   a,    20   b  remain in place on the respective measurement region  16  and do not mix with adjacent drops of liquid  20   a,    20   b  and/or do not flow into an adjacent measurement region  16 . 
         [0085]    The above-mentioned spotting may theoretically be carried out as desired, either before or after the division of the chips  11  and/or the electrical connection and installation of the chip  11  in question. Preferably, the spotting takes place after the connection and installation of the chips  11 . 
         [0086]    The spotting or application of drops of liquid  20   a,    20   b  serves, in particular, only to functionalize the individual measurement regions  16 , i.e., particularly to precipitate or bind special molecules for trapping or reacting with molecules that are to be detected in a sample. The drops of liquid are removed again, in particular, after a desired immobilization or binding of the special molecules. Thus, spotting also serves in particular to prepare the chip  11  or the measurement regions  16 . 
         [0087]    The sample liquid itself, containing molecules that are to be measured or detected, is subsequently applied to the chip  11  or the measurement regions  16 —for example over the entire surface and/or using a membrane which covers, as flatly as possible, the measurement regions  16  with the sample liquid located thereon—when the chip  11  is used correctly. The membrane may interact with the compartmental structure  24 , in particular may lie on it, in order to distribute the sample liquid over the measurement regions  16  and/or to achieve fluidic separation of the sample liquid in the various measurement regions  16  from one another. 
         [0088]    However, alternatively, it is also possible to apply one or more samples that are to be measured to the previously functionalized measurement regions  16  by spotting. 
         [0089]    Individual aspects and features of the various embodiments, variants and alternatives may also be implemented independently of one another, but also in any desired combination.