| DE19648844C1 | 1997-09-18 | |||
| JPH10153388A | 1998-06-09 | |||
| JPH054232A | 1993-01-14 | |||
| US5735985A | 1998-04-07 | |||
| US5888445A | 1999-03-30 |
| 1. | A method of producing ceramic precision elements, such as small building elements for electronic, optoelectronic or mechanical constructions, characterised by inserting ceramic material between a nickel shim/template and a pressure plate that can be actuated adjustably by pressurised gas or pressurised liquid such as to press the pressure plate against the ceramic material on the nickel shim/template while baking said ceramic material so as to obtain form an impression of the pattern provided on the nickel shim/template, said pattern having been created on the nickel shim/template by covering a micromachined silicon disc that carries a pattern of the intended building element with a metal layer and then etching away the silicon to expose the pattern replicated on the metal layer and forming the aforesaid nickel shim/template. |
| 2. | An arrangement for producing ceramic precision elements, such as small building elements for electronic, optoelectronic or mechanical constructions, characterised by two mutually coacting devices, of which one is comprised of a nickel shim/template (6) that has been produced by providing a silicon disc with a pattern corresponding to the intended building element and covering said disc with a metal layer and then etching away the silicon so as to obtain said nickel shim/template, and where the other device is comprised of a pressure plate (11) which can be actuated adjustably by pressurised gas or liquid, wherein said pressure plate can be pressed against the ceramic material (9) on the nickel shim/template during a baking process so as to form an impression of the pattern carried by the nickel shim/template and forming the ceramic building element. |
| 3. | An arrangement according to Claim 2, characterised in that the arrangement includes a sintered metal plate (10) positioned between the pressure plate (11) and the ceramic material (9) for conducting away gases that are generated during the shaping process of the building element. |
| 4. | An arrangement according to Claim 2, characterised by a cylinder (13) which houses a piston (15) that functions to force the pressure plate (11) against the ceramic material (9) on the nickel shim/template (6). |
| 5. | An arrangement according to Claim 2, characterised in that the pressure plate (11) includes throughpenetrating vents (12) through which released gases are able to pass during the shaping process of the building element. |
| 6. | An arrangement according to Claim 2, characterised in that an attachment means (3) for attachment of the piston cylinder device (13,15) is connected to a nickel shim/template supporting means (2) which acts as a counter pressure means as the piston exerts pressure on the ceramic material on the nickel shim/template (6). |
| 7. | An arrangement according to Claim 6, characterised in that the attachment means is a lid or cover means (3) and the underlying support means is a bottom means (2); and in that the lid or cover and the bottom are secured to a casing (1) by means of fastener devices (4,5), the casing housing the pistoncylinder device (13,15), the pressure plate (11) with or without the sintered metal plate (10), the inserted ceramic material (9) and the nickel shim/template (6). |
| 8. | A ceramic precision building element for electronic, optoelectronic or mechanical constructions, characterised in that the building element has been produced by placing ceramic material (9) between a pressure plate (11) and a patterned nickel shim/template (6) that have been subjected to pressure and heat such as to replicate the pattern on the nickel shim/template and therewith form the intended ceramic building element. |
DESCRIPTION OF THE BACKGROUND ART Present-day technology for creating structures in ceramic carriers is essentially limited to creating holes that are later used to form vias. Metalisation of the holes can provide an electric connection between ceramic plates/ceramic layers. A pattern of electric conductors can then be provided on the plates by screen-printing or thin film deposition. It has not been possible to give the resultant carriers any further patterns of a more complex nature in the ceramic, without needing to apply expensive methods.
SUMMARY OF THE INVENTION By being able to vary the force at which a piston presses a ceramic material against a nickel shim/template while baking ceramic material that is in a formative or plastic state into a solid state, it is possible to produce ceramic precision elements, such as ceramic building elements, with complicated geometric structures in three dimensions, and to adapt the method of manufacture to suit different ceramic materials so as to produce ceramic building elements that have the properties desired. With an arrangement that is designed to enable the force with which a piston presses ceramic material against a nickel shim/template during baking plastic ceramic material into a solid state, it is possible to transfer a pattern on the shim/template onto the ceramic material with very great precision. The arrangement also enables the fact that gas will be generated as the ceramic material is baked to be taken into account, said material having been mixed with polymeric constituents and solvent prior to the baking process in order to render the ceramic material plastic, ductile. The gas developed during the baking process will preferably be evacuated from the ceramic, up through a layer of sintered metal, through a pressure plate and then through a surrounding chamber and from there to the surrounding atmosphere.
The described technique enables mounting surfaces on which optoelectrical components, electrical components and mechanical components can be mounted to be integrated on one and the same building element at mutual level differences and in level differences with other surfaces, and to create V- grooves for receiving optical fibres. The building element
produced in accordance with the method can then be refined by screen-printing or by thin film deposition so as to create electric conductor paths in accordance with generally known techniques. Electric conductors can also be printed on the ceramic material prior to baking said plastic ceramic material into a solid or.. firm state. The arrangement by means of which the building elements are produced will preferably be made of a material that is able to withstand high temperatures in repeated cycles. Ceramic titanium or chromium alloys for instance can be used to this end. The invention also enables ceramic building elements/carriers of extremely complicated shapes and designs to be produced at low costs, and enables the template/nickel shim to be reused.
The invention will now be described in more detail with reference to a preferred embodiment thereof and also with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of the inventive arrangement and shows said arrangement in a prepared state for baking ceramic material placed therein.
Figures 2a to 2f illustrate a method of producing a nickel shim for use in connection with the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS Figure 1 illustrates an arrangement in which building elements can be formed and baked in ceramic material in accordance with the present invention. The arrangement
comprises a generally circular casing 1 that has a circular bottom 2 and a circular lid or cover 3. The bottom and lid are secured in the casing by means of four bolts 4 and four nuts 5. A circular nickel shim 6 that includes a planar surface 7 and two V-grooves 8 is placed on the bottom 2.
Ceramic material 9 to.. be shaped is placed between the circular nickel shim on the bottom 2 and a circular sintered metal element 10 that lies beneath a circular pressure plate 11. The circular pressure plate includes several gas vents, preferably more than five. A cylinder 13 is firmly fixed to the lid with the aid of screws 14 and extends between said lid and the bottom 2. A fluid-operated piston is mounted in the cylinder and adapted to press, with an adjustable force, the circular pressure plate with the circular sintered metal element against the ceramic material on the circular nickel shim so as to make an impression of the shim in the ceramic material. The piston is fitted with at least two sealing rings 16, so the piston will be sealed effectively against the inner wall of the cylinder. The arrangement includes a fluid connection 17 which enables pressurised fluid, such as propellant gas, to be delivered from an external pressure source to an inner space 18, therewith driving the moveable piston down into pressure contact with the circular pressure plate. For the purpose of baking the enclosed ceramic material, there is connected to the arrangement a controllable heat source which coacts with temperature registering means so as to enable the baking temperature to be adapted to the ceramic material concerned. The space between the cylinder, piston and the circular casing communicates with ambient atmosphere through two ventilation holes 19. Gases that are released in the pressing process during heating of a building element in the ceramic material
will pass through the sintered metal, and then through the gas vents and the space between the cylinder and the piston and the casing and then through the ventilation holes and out to the ambient atmosphere.
Subsequent to having placed a nickel shim 6 in position with its planar side facing down towards the bottom 2, a ceramic material 9 has been placed on the upwardly facing patterned side of said shim, this patterned side including a planar surface 7 and V-grooves 8. The gas-permeable sintered metal element 10 is placed on the ceramic material 9 and the pressure plate 11 then placed on top of the sintered metal element. The cylinder 13 is fixed firmly to the lid or cover by means of screws 14, and the piston moves in the cylinder 13 while sealed against the cylinder wall with the aid of said sealing rings 16. The pressure chamber 18 in the cylinder 13 is pressurised for actuation of the piston with the aid of gas or liquid delivered through the connection 17. After having placed all elements of the arrangement in an oven that has been set to an appropriate temperature or temperature profile with respect to the ceramic material concerned, and after having connected to the pressure chamber a gas or liquid source which enables the pressure of said gas or liquid to be regulated, the pressure can be controlled and regulated as the ceramic material is baked to a firm or solid state so that the finished ceramic building element will have the properties desired. The gas generated during baking of the ceramic material passes up through the gas-permeable sintered metal 10 and then through vents 12 in the pressure plate 11 and out through the evacuation holes 19.
Upon completion of the manufacturing process, the arrangement is dismantled and the finished ceramic is released from the nickel shim 6 with the aid of a separation layer on said shim, for instance. The nickel shim released from the ceramic 9 can now be used in further manufacturing cycles.
Figures 2a-f show the various stages in the manufacture of a nickel shim/template. Figure 2a shows a micro-worked silicon disc 21 having a profiled surface, such as a grooved surface.
The pattern of grooves or the like can be produced by one or more of the following processes: dry etching, wet etching, laser machining, or spark machining. Figure 2b illustrates a thin metal layer, a starting layer 22, that has been sputtered or vaporised on the micro-worked silicon disc to enable a following plating process to be started. In the Figure 2c illustration, the starting layer 22 on the silicon disc 21 has been metal plated, preferably nickel plated, so as to provide a so-called nickel shim 6. Figure 2d shows that the nickel shim 6 seated firmly on the silicon disc 21 has been made planar by mechanically machining, e. g. grinding, the disc. Figure 2e shows the nickel shim 6 separated from the silicon disc 21. Figure 2f shows the nickel shim 6 coated with a separation layer 24 that enables separation in a later stage.
It will be understood that the invention is not restricted to the aforedescribed and illustrated embodiment thereof and that modifications can be made within the scope of the following Claims.
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