Abstract
The invention relates to a method for producing reaction vessels from glass and to the glass reaction vessels obtainable by this method. The method comprises the following steps: 1. irradiating the surface of a first glass sheet by means of a laser beam of a wavelength for which the first glass sheet is permeable, 2. etching the first glass sheet to form recesses that extend over the complete thickness of the first glass sheet, and 3. connecting a second sheet with a surface of the first glass plate.
Claims
1. A method of producing a plurality of glass reaction vessels formed as recesses in a first glass plate, comprising the steps of irradiating laser pulses of a wavelength for which the first glass plate is transparent onto the locations of the first glass plate at which each of the recesses is to be formed, etching the first glass plate for a period of time sufficient to create the recesses at the locations, the etching being performed until the recesses have a depth extending through the full thickness of the first glass plate, connecting a second plate to a surface of the first glass plate, wherein the connecting is performed by applying glass frit to a surface of the first glass plate or to a surface of the second plate placing the first glass plate against the second plate and conducting heating and/or anodic bonding.
2. The method according to claim 1, wherein the depth of the recesses is at least 3 μm.
3. The method according to claim 1, wherein the recesses have a depth to diameter aspect ratio of at least 2.
4. The method according to claim 1, wherein a surface of the first glass plate is coated with etch resist prior to the etching and the etch resist is removed after etching and before the connecting.
5. The method according to claim 1, wherein the second plate consists of glass, silicon, sapphire, ceramic, metal or combination of at least two layers thereof.
6. The method according to claim 1, wherein the wherein the laser pulses are at a plurality of spaced-apart positions at the locations.
7. The method according to claim 6, wherein a share of the positions laser pulses are irradiated less deeply into the first glass plate to a first thickness section, a share of the positions laser pulses are irradiated deeper into the first glass plate up to an adjacent second thickness section wherein during etching a recess extending over the first thickness section is formed and partial recesses spaced by partial walls and extending over the second thickness section are formed.
8. The method according to claim 7, wherein the positions are arranged at a distance of at most 10 μm, wherein at least three positions are spaced at least 20 μm apart.
9. The method according to claim 1, wherein a focal position of the laser laser pulses is adjusted such that laser pulses penetrate into the first glass plate only up to a thickness section which does not extend over the entire thickness of the first glass plate.
10. The method according to claim 1, comprising irradiating a laser beam along a circumferentially closed path at the locations.
11. The method according to claim 14, wherein the circumferentially closed path is formed by laser beam pulses irradiated side by side.
12. (canceled)
13. The method according to claim 4, wherein the etching is performed until a chamfer is formed adjacent to the surface coated with etch resist around the recess.
14. The method according to claim 1, wherein the connecting comprises applying glass frit in paste form by a printing process to the surface of the first glass plate, arranging the second plate against the applied glass frit, and heating the arrangement of the first glass plate and second plate with the glass frit applied therebetween.
15. The method according to claim 1, comprising applying a first strip conductor to the first surface of the first glass plate opposite to the second plate, and applying second strip conductors to the surface of the second plate facing the first glass plate, prior to the connecting.
16. The method according to claim 15, wherein the second plate comprises ditches and the second strip conductors are applying in the ditches.
17. The method according to claim 1, comprising applying strip conductors on the first glass plate such that the strip conductors cover at least a section of the inner wall of the recesses.
18. (canceled)
19. The method according to claim 1, comprising connecting a third plate having third recesses extending through its full thickness to the first surface of the first glass plate with the third recesses matching the recesses of the first glass plate.
20. The method according to claim 1, wherein the second plate comprises second recesses and the connecting comprises connecting the second plate to the first plate with its second recesses adjacent to the recesses of the first glass plate.
21. An array of reaction vessels formed as recesses, comprising: a plurality of the recesses in a first glass plate, wherein the recesses comprise a depth of at least 30 μm and depth to diameter aspect ratio of at least 2, wherein the recesses extend through the full thickness of the first glass plate, and a second plate forming a bottom of the reaction vessels is connected to the first glass plate (1).
22. The array according to claim 21, comprising strip conductors on a surface of the second plate, the strip conductors extend into an area encompassed by the recesses.
23-29. (canceled)
Description
[0057] The figures schematically show in
[0058] FIG. 1 in cross-section perpendicular to the surface of the first glass plate, an embodiment of the reaction vessels in glass made of two glass plates,
[0059] FIG. 2 in top view of the first surface of the first glass plate the optical analysis of a reaction vessel produced according to the invention,
[0060] FIG. 3a) and b) another embodiment in cross-section perpendicular to the surface of the first glass plate,
[0061] FIG. 4a), b), c) embodiments in cross-section perpendicular to the surface of the second glass plate,
[0062] FIG. 5a)-b) embodiments with strip conductors in cross-section perpendicular to the surface of the first glass plate,
[0063] FIG. 6a)-c) further multi-part embodiments in cross-section perpendicular to the surface of the first glass plate, and in
[0064] FIG. 7 another embodiment in cross-section perpendicular to the surface of the first glass plate.
[0065] FIG. 1 shows a first glass plate 1 in which the recess 2 extends through the full thickness and the bottom 3 is formed by a second glass plate 6 tightly connected to the second surface 5 of the first glass plate 1.
[0066] FIG. 2 shows, in top view of a first glass plate 1, a recess 2 whose wall forms a strong optical contrast with the bottom 3, so that the wall is clearly shown as a circumferential boundary of the bottom 3. Under illumination directed through the bottom 3, a particle, e.g. a biological cell Z, can be seen with good contrast against the bottom 3, especially when the cell Z is marked by a dye, e.g. a fluorescent dye.
[0067] FIG. 3a) shows a first glass plate 1, the second surface 5 of which is coated over its entire surface with etch resist 8, e.g. a plastic film with a UV-soluble adhesive, after irradiation of a laser pulse perpendicular onto the glass plate 1 and subsequent etching. The etching creates the recess 2 symmetrically about the light path of the laser pulse so that the longitudinal central axis 7 extends along the original light path of the laser pulse. The etching starts from the first surface 4 and creates a frustoconical recess 2 that extends to the etch resist 8. A chamfer or undercut 9 is created around the recess 2 along the second surface or between the second surface 5 and the etch resist 8.
[0068] FIG. 3b) shows glass vessels formed as recesses 2 in a first glass plate 1 and extending through the full thickness of the first glass plate 1. The bottom 3 of the recess is formed by glass frit 10, which is applied to completely cover the surface of the second plate 6 and also fills the area of the chamfer 9.
[0069] FIG. 4 shows embodiments of each of a recess 2 formed as a single piece in a second glass plate 6. This shows that irradiating laser pulses onto the first surface 24 of the second glass plate at a plurality of positions spaced apart by, e.g. 1 to 10 μm and therefore forming a location, at which exactly one recess 2 is produced by etching. Therein, a concave recess 12 may be formed by the etching at each position 12 on the bottom 3 of the recess 2.
[0070] As shown in FIG. 4a), a glass tip 11 projecting in perpendicular to the first surface 24 from the bottom 3 into the recess 2 is produced during etching if at least 3 positions 12 onto which laser pulses are irradiated are arranged at a greater spacing, e.g. at a distance of 20 μm. Therein, each position 12 onto which a laser pulse was irradiated, during etching results in a concave recess in the bottom 3.
[0071] FIG. 4b) shows that laser pulses irradiated at individual positions 13 and penetrating deeper into the thickness of the second glass plate 6 form further recesses 14 there during etching, which extend deeper into the second glass plate 6 than the recess in other positions 12 where laser pulses were irradiated to a lesser depth into the second glass plate 6. The depth of penetration of the laser pulses into the second glass plate 6 can be predetermined by adjusting the focus position and/or the strength of the pulse energy of the laser pulses.
[0072] FIG. 4c) shows that irradiating laser pulses penetrating deeper into the second glass plate 6 at positions 13 arranged alongside each other during etching form another recess 14 there extending deeper into the thickness of the second glass plate 6 than the recess whose bottom 3 is formed during etching from other positions 12 in which the laser pulses have been irradiated less deeply into the second glass plate 6.
[0073] FIGS. 5a) and b) show embodiments in which a first strip conductor 15 is applied to the first glass plate 1, in this case to its first surface 4, and the second plate 6 has a second strip conductor 16 lying thereon on its surface, which is flat and faces the first glass plate 1. The first strip conductor 15 and the second strip conductor 16 may be applied, e.g. by sputtering, printing or by chemical or galvanic deposition or combinations thereof. One of the first and second strip conductors 15, 16 may be applied over the entire surface, and the other strip conductor 15, 16 may be formed in the form of spaced apart tracks which traverse the cross-section of the recess 2. The layer of glass frit 10 disposed between the first glass plate 1 and the second plate 6 and solidified after softening connects these two plates 1, 6 and spaces the first strip conductor 15 from the second strip conductor 16 so that these strip conductors contact a liquid contained in the recess 2 at a distance from each other. Optionally, in general, the layer of glass frit 10 may be disposed solely between the first glass plate 1 and the second plate 6 and leave the area of the recesses 2 exposed, or the layer of glass frit 10 may extend across the thickness of the layer of the first strip conductor 15 into the recess 2 to within a distance of the second strip conductor 16 or to adjacent the second strip conductor 16.
[0074] FIG. 5a) shows an embodiment in which the second strip conductor 16 runs in ditches 17 formed as recesses in the second plate 6, preferably by irradiation with laser pulses along the course of the ditches with subsequent etching.
[0075] FIG. 5b) shows an embodiment in which the second strip conductor 16 is arranged on the flat surface of the second plate 6.
[0076] FIG. 6a) shows the arrangement of at least two, presently depicted ten, recesses 2, the longitudinal central axes 7 of which are arranged at equal distances from one another. The recesses 2 are enclosed by walls which extend through the entire thickness of the first glass plate 1. Therein, the recesses 2 taper from the first surface 4 to the second surface 5 of the first glass plate 1. The cross-sectional openings of the recesses 2 are covered by the second plate 6 in the plane of the second surface 5.
[0077] FIG. 6b) shows an embodiment in which a third plate 18 is connected to the first surface 4 of the first glass plate 1, wherein the third plate 18 having third recesses 23 extending through its thickness and covering at least two, in FIG. 7 b) ten, recesses 2 formed in the first glass plate 1. The distance between the longitudinal central axes of the recesses 2 in the first glass plate may be, e.g. 10 to 100 μm.
[0078] FIG. 6c) shows an embodiment in which a recess is produced in the first glass plate 1 by etching after the first glass plate 1 has been irradiated with laser pulses passing through its full thickness at the locations where partial recesses 2′ are formed, and has been irradiated therebetween with laser pulses extending maximally over an upper thickness section 20. The upper thickness section 20 extends from the first surface 4 of the first glass plate 1 to adjacent to the partial recesses 2′, leaving partial walls 22 between the partial recesses 2′ at the locations where laser pulses were irradiated maximally to the depth of the upper thickness section 20. The terminal cross-sectional openings of the partial recesses 2′, which are opposite to the first thickness section 20, are covered by a second plate 6, which is connected to the first plate 1.
[0079] FIG. 7 shows an embodiment in which the second plate 6 has second recesses 19 in the area of the recesses 2 formed in the first glass plate 1. The second recesses 19 may optionally extend only into a portion of the thickness of the second plate 6, or may extend through the full thickness of the second plate 6, as shown here. The second recesses have diameters in the plane of the surface of the second plate 6 joined to the first glass plate 1 that are smaller than the diameter of a cell Z by a factor of 5 to 10, e.g. A second plate 6 with second recesses 19 extending through its full thickness form a retaining device for larger particles, e.g. a cell Z.
[0080] According to a preferred embodiment, in FIG. 7 the second recesses 19 taper and have their smaller diameter in the plane of the surface of the second plate 6 facing the first glass plate.
LIST OF REFERENCE SIGNS
[0081] 1 first glass plate 14 further recess 14 further recess [0082] 2 recess 15 first strip conductor [0083] 2′ partial recess 16 second strip conductor [0084] 3 bottom 17 ditch [0085] 4 first surface 18 third plate [0086] 5 second surface 19 second recess [0087] 6 second plate 20 upper, first thickness section [0088] 7 longitudinal central axis 21 lower, second thickness section [0089] 8 etch resist 22 partial walls [0090] 9 chamfer, undercut 23 third recess [0091] 10 glass frit 24 first surface of the second plate [0092] 11 glass tip 25 second surface of the second plate [0093] 12 position of irradiated laser pulse Z cell [0094] 13 position of more deeply irradiated laser pulse
