DE102011083423A1 - Contact spring assembly and method of making the same - Google Patents

Abstract

The invention relates to a contact spring arrangement comprising a substrate (100) having at least one contact surface (130), a spring element (200) on the substrate (100), and a conduction element (300) attached to the first contact surface (130) and over the spring element (200) is arranged.

Description

The present invention relates to a contact spring arrangement and to methods for producing a contact spring arrangement.

For producing an electrically conductive contact between a plurality of electronic modules and / or printed circuit boards, a contact spring arrangement with a spring contact is frequently used. The contact spring assembly is inserted into a designated contact. Here, the spring contact is elastically deformed and there is a frictional connection between contact and spring contact. To interrupt the contact, the contact spring assembly can be pulled out of the contact nondestructive.

As a contact spring arrangement so far contact springs are used in the form of prefabricated contact blades, which are arranged on bands. Conventionally, the contact blades are designed as torsion springs or leaf spring blades. The contact blades are made of metal, often made of resilient metal. Due to the materials used such lamellar bands are very expensive to manufacture. In addition, the contact blades often have only a low current carrying capacity.

The contact blades are fastened by means of a contact rail on the module or the circuit board. This assembly requires additional work steps.

Consequently, it is an object of the invention to provide a contact spring assembly and a method for producing the same, which are simple and inexpensive to manufacture and use.

This object is achieved with regard to the device by the features specified in claim 1.

Accordingly, the object of the invention is achieved by a contact spring arrangement having a substrate with at least one contact surface, a spring element which is arranged on the substrate and a line element which is arranged on the at least one contact surface and on the spring element.

As the substrate, any organic and inorganic based circuit carriers may be used, e.g. Circuit boards (PCBs) or ceramic substrates (DCB, Direct Copper Bond), IM (Insulated Metal), HTCC (High Temperature Cofired Ceramics) and LTCC (Low Temperature Cofired Ceramics) substrates.

The contact surface is formed on a surface of the substrate on an electrically conductive layer, e.g. on a copper layer. Usually, the substrate comprises a plurality of contact surfaces, with which e.g. arranged on the substrate semiconductor devices may be electrically conductively connected.

The spring element has the ability to elastically deform under a mechanical load and to return to its original shape after removal of the mechanical stress. The spring element is particularly suitable for temporarily storing energy which is introduced by compressive forces as strain energy and for returning the stored energy to the environment after the pressure forces have been removed.

In a particular embodiment, the spring element consists of at least one elastic material, ie a material which returns after deformation by compression back into the original shape. Examples of possible elastic materials are elastomers, and in particular polymers and rubbers modified with regard to their insulating properties. For example, silicone polymers, such as those sold under the name "Elastosil" by Wacker Chemie, or polymer films, such as, for example, TSA-15 from Toray can be used. For example, elastomeric materials can be used, so materials with weitmaschig cross-linked macromolecule chains. As elastic materials, for example, materials with a modulus of elasticity E of 100,000N / m ² (1E5 Newton / square meter) to 500,000,000 N / m ² (5E8 N / m ² ) and in particular with a modulus of elasticity E of eg 1E6 N / m ² to 1E7 N / m ² are used. The use of elastic materials makes it possible to achieve the functionality of the spring element already by the choice of material. The spring element may be formed as an elastic elevation over the substrate. The spring element has a height perpendicular to the substrate surface, a width in the longitudinal direction of the conduit member and a length transverse to the longitudinal direction of the conduit member. For example, the spring element may have a height above the substrate of 10 microns (μm) to 2 millimeters (mm), and preferably has a height of 100 μm to 1 mm. An elaborate geometric design of the spring element is not necessary.

In a further embodiment, the spring element consists of electrically insulating material. Thus, the spring element can also be arranged over regions of the substrate in which conductive track structures are formed.

In a further embodiment, the spring element has an upper side, which has an arcuate profile in cross section, ie the height of the spring element increases steadily from the edge regions to the central region of the cross section. In particular, viewed in cross-section, the upper side of the spring element can be shaped convexly, at least in the middle region. The upper side is in this case the side of the spring element facing away from the substrate. The arcuate profile provides a spatially defined contact between contact spring assembly and contact in the installed state and for a progressive course of the spring force as a function of travel, ie with increasing spring travel, the spring force increases.

In a further embodiment, the spring element has a width which decreases stepwise with increasing distance from the substrate. As a result, a spring force largely constant spring force can be achieved.

In a further embodiment, the spring element has at least a first material layer and a second material layer arranged above the first material layer. Alternatively, more than two, e.g. three or four layers of material are used. For example, the material layers may be made of the same elastic material or different materials may be used. Alternatively, only one of the material layers may be made of elastic material and the other material layer may consist of a non-elastic material. As a result, an improved adjustability of the spring force can be achieved.

In a further embodiment, the contact spring arrangement further comprises a semiconductor chip or an electronic component which is arranged on the substrate, and a film layer, in particular an electrically insulating film layer, which is arranged on subregions of the semiconductor chip or the electrical component and on subregions of the substrate is. The first material layer or the second material layer of the spring element is in this case formed from the film layer. The film layer may consist of any thermoplastics, thermosets and mixtures thereof. Preferably, a film layer of a plastic material on polyimide (Pi), polyethylene (PE), polyphenol, polyetheretherketone (PEEK) - and / or epoxide-based is used. The film may have an adhesive layer to improve adhesion to the surface. The film may have a thickness of 10 .mu.m to 500 .mu.m, preferably the thickness of the film is 25 .mu.m to 150 .mu.m. The use of the same, already in the manufacturing process required materials, means a further cost savings.

The above-mentioned line element is the element of the contact spring arrangement, which produces an electrically conductive connection to the contact surfaces of the substrate and - in the installed state - the electrical contact with the contact. For this purpose, the conducting element is made of an electrically conductive material, e.g. a metal formed. All galvanically depositable metals can be used as materials. For example, copper, copper alloys, aluminum, aluminum alloys, nickel, nickel alloys, silver, silver alloys, titanium, gold, tin, or layers of several of these materials may be used, such as e.g. a layer sequence of titanium / copper / nickel / gold. The conduit element extends in its longitudinal direction from the contact surface via the spring element.

According to a further embodiment of the invention, the line element is formed from at least one bonding wire. Alternatively, the line element can also be formed from a plurality of, that is, two or more bonding wires. Depending on the number of bonding wires and the required current carrying capacity of the contact spring arrangement, the diameter of the bonding wire can be selected. For example, bond wires with a diameter of 200 .mu.m to 300 .mu.m can be used, but alternatively bonding wires with a larger or smaller diameter can also be used.

In a further embodiment of the invention, the conduit element is formed from at least one flat band. Alternatively, the conduit member may be formed of two or more flat belts. The ribbon has a thickness transverse to the substrate surface and a width transverse to its longitudinal direction. The flat strip may have, for example, a thickness transverse to the substrate surface of 100 .mu.m to 300 .mu.m, but alternatively other strip thicknesses may be used, depending on the technical requirements. For example, copper or aluminum ribbon can be used. The width of the flat belt can be selected according to the technical requirements.

In a further embodiment, the conduit element comprises a galvanically deposited metal. The electrodeposited material may have a thickness of 30 microns to 400 microns, preferably, the electrodeposited material may have a thickness of 50 microns to 200 microns. However, other thicknesses may be used depending on the technical requirements. Through the use of materials that are common in the construction and connection technology, a particularly inexpensive contact spring arrangement can be provided.

In a further embodiment, the line element lies flat on the spring element, ie over the spring element is the underside of the Conduit element not only punctiform but completely on the spring element. In this way, a particularly good support effect can be achieved by the spring element.

In a further embodiment, the contact spring arrangement has only one spring element and one line element. This is a particularly easy to manufacture arrangement with low space requirement.

With regard to the method, the object of the invention is achieved by the measures of claim 8.

Accordingly, the object of the invention is achieved by a method in which a substrate is provided with at least one contact surface, a spring element is formed on the substrate and a line element is formed, so that after the formation of the spring element and the line element, the line element at the at least a contact surface and is arranged above the spring element.

The system of the spring contact is broken down in terms of its functionality into separate functional units, namely a spring element which provides the required spring force and effect, as well as a line element which is electrically conductive and thus enables the electrical contact. The two separate functional units can be realized separately with simple and known methods. As a result, a particularly cost-effective production is possible. Thus, the contact spring assembly can be made by methods commonly used in the manufacture of electronic modules and circuit boards.

According to one embodiment, the spring element is applied to the substrate by means of a stencil or screen printing technique, e.g. by solder paste printing or solder resist paint pressure. For this purpose, the material to be applied is painted through a fabric surface. A stencil formed on the fabric surface causes the material in the areas under the stencil not to pass through the fabric. The use of conventional processes makes the manufacture of the spring element particularly reliable and inexpensive.

According to a further embodiment, a prefabricated element is applied to the substrate for forming the spring element. By means of prefabricated elements particularly narrow and high spring elements can be formed, whereby a contact spring arrangement can be realized with a small footprint.

In a further embodiment, a semiconductor chip is further arranged on the substrate, and forming the spring element comprises applying a foil to the substrate and onto the semiconductor chip, and structuring the foil. The film can be glued or laminated to the substrate. In a further embodiment, the film is laminated under vacuum. The film may consist of any thermoplastics, thermosets and mixtures thereof. Preferably, a film of a plastic material on polyimide (Pi), polyethylene (PE), polyphenol, polyetheretherketone (PEEK) - and / or epoxide-based is used. The film may have an adhesive layer to improve adhesion to the surface. The film may have a thickness of 10 .mu.m to 500 .mu.m, preferably the thickness of the film may be 25 .mu.m to 150 .mu.m. The lamination may e.g. with a vacuum press, by vacuum deep drawing, hydraulic vacuum pressing, vacuum pressure pressing or similar laminating methods, e.g. at a pressure of -850 mbar. The lamination can be carried out, for example, at temperatures of 100 ° C to 250 ° C and a pressure of 1 bar to 10 bar. The structuring of the film can be carried out, for example, using laser ablation or photochemical methods. Thus, the formation of the spring element can be largely or completely integrated into existing processes.

In a further embodiment, the line element is formed during a process step, with which an electrically conductive connection between the semiconductor chip and the substrate is produced. The integration of the process into already existing process steps contributes to cost savings.

In further embodiments, the conducting element can be formed using electrodeposition, or the conducting element can be arranged by means of a bonding process on the at least one contact surface, e.g. by wire bonding, in particular thick wire bonding, or ribbon bonding.

The spring element is formed in an embodiment in front of the line element. In another embodiment, the spring element is formed after the line member. For this purpose, for example, a subsequent refill process, an underfill process can be used, d. H. the conduit element is subsequently underfilled with a material for forming the spring element.

The method achieves particular advantages in that conventional technologies can be used to produce the contact spring arrangement. In particular, the contact spring assembly with the same technologies and in the same Process steps are made, with which also a contacting of one or more arranged on the substrate active semiconductor devices takes place. Thus, for example, the contact spring arrangement can be formed partially or completely with the method known as SIPLIT for contacting electrical contact surfaces, wherein the method steps described above for applying a film to the substrate and structuring the film can be used and the conduit element is formed in a process step galvanically in which an electrically conductive connection is also produced between the semiconductor component and the substrate.

Further advantageous embodiments of the invention will become apparent from the dependent claims.

In other words, the solution is based on the principle of decomposing the system spring contact into separate functional units (elastic element and electrically conductive element), which can be installed separately by known methods. The main advantage lies in the cost-effective production justified. In some cases, these methods are already used in the production of electronic modules or printed circuit boards anyway. This is especially the case with RF module developments with SIPLIT technology. Thus, the contact spring assembly can be produced virtually without additional process steps with.

Here, the contact spring assembly is constructed in two steps one after the other. In this case, the actual spring element is a separately generated, elastic survey on the substrate. About this an electrically conductive trace is generated in a second sub-step. Both together form the spring contact of the contact spring arrangement.

The technologies for forming the contact spring assembly are, in particular, connection and termination techniques (AVT) in the chip industry, e.g. Wire bonding (in particular thick wire bonding with a wire diameter of 200 to 300 μm), ribbon bonding, galvanic rewiring (thin-film technologies, lithography, seed layer sputtering, electroplating, seed layer etch), SIPLIT (Siemens planar interconnect technology), stencil and screen printing processes (eg solder paste printing , Solder resist paint pressure).

The above-described characteristics, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of the embodiments, which will be described in detail in conjunction with the drawings.

Show it:

1 a cross-sectional view of a contact spring assembly according to a first embodiment,

2 a perspective view of the contact spring assembly of 1 .

3 a cross-sectional view of the contact spring assembly 1 in the installed state in a contact,

4 FIG. 3 is a flow chart illustrating the process order of a first exemplary manufacturing method. FIG.

5 and 6 Cross-sectional views of a contact spring assembly according to the first and a second embodiment,

7 a perspective view of the spring element according to the second embodiment,

8th and 9 Cross-sectional views of a contact spring assembly according to a third and fourth embodiment,

10 to 12 Cross-sectional views of a contact spring assembly according to the first, fifth and sixth embodiments,

13 FIG. 3 a flowchart for illustrating the process sequence of a second exemplary production method, FIG.

14 and 15 Cross-sectional views of a contact spring assembly according to a seventh embodiment,

16 to 18 perspective views of contact spring assemblies according to an eighth, ninth and tenth embodiments.

1 shows a schematic cross section through a contact spring arrangement 10 according to a first embodiment. The contact spring arrangement has a substrate 100 , here a circuit board, with a base plate 110 , Furthermore, the substrate has 100 on the upper side of the base plate, a conductive layer having a first contact surface 120 , a second contact surface 130 and a third contact surface 140 on. The contact surfaces are formed of a conductive material such as copper. Furthermore, the substrate may be another layer 150 have, for example, may be an insulation layer and the portions of the contact surfaces and / or the base plate 110 covered.

It is understood that the substrate 100 may include more contact surfaces. Likewise, on the substrate 100 Semiconductor devices, such as transistors may be arranged, which for the sake of simplicity in 1 are not shown.

The substrate 100 points at the bottom of the base plate 110 furthermore a metallic layer 170 on. This may for example be a copper layer and serve to produce a wiring structure. In other embodiments, there is no metallic layer on the underside.

On the substrate 100 is a spring element 200 arranged. According to 1 is the spring element on the base plate 110 arranged, alternatively, however, the spring element may for example also be arranged partially or completely on a contact surface. The spring element 200 lies flat on the substrate 100 and thus has an underside adapted to the topography of the substrate 210 , The substrate may have a planar or stepped topography. Furthermore, the spring element has one of the underside 210 opposite top 220 , The spring element 200 has, viewed in cross section, a height H above the substrate 100 , which is the largest in the middle region and decreases towards the sides. The spring element thus forms an elevation above the substrate. For example, the height of the spring element 200 in the middle range 10 microns to 2 millimeters.

Above the spring element 200 is a conduit element 300 educated. The pipe element 300 consists of an electrically conductive material, preferably a metal. According to 1 the conduit element extends from a first end 310 at the first contact surface 120 is arranged until a second end 320 at the second contact surface 130 is arranged. The pipe element 300 provides an electrically conductive connection between the first contact surface 120 and the second contact surface 130 ready. The pipe element 300 points in its middle area between the first end 310 and the second end 320 a greater height above the substrate than at the ends 310 and 320 , The spring element 200 is thus between the first and second contact surface 120 . 130 and under the conduit element 300 arranged.

According to 1 lies the conduit element 300 only partially on the spring element 200 on and is near the contact surfaces 120 and 130 spaced from this. This distance is optional, as can the conduit element without distance to the spring element 200 be educated.

2 shows a perspective view of the contact spring assembly 10 according to the first embodiment. The spring element 200 has the shape of an elongated shaped body with a length L perpendicular to the in 1 cross section shown. The shaped body can be, for example, a prefabricated element which is adhesively bonded to the substrate. The shaped body may be a solid element, or alternatively, the shaped body may have one or more cavities inside. Above the spring element 200 are four pipe elements 300 arranged. The length L of the spring element 200 as well as the number of line elements 300 can vary within a wide range depending on the technical requirements. For example, the length L may be equal to the height H of the spring element 200 be, or the length L may be many times greater than the height H of the spring element 200 , for example, three times, ten times or one hundred times. The spring element may for example have a length of 500 microns to 20 cm (centimeters), for example, a length of 500 microns to 5 cm, alternatively, the length of the spring element 200 be equal to one side of the circuit board. The contact spring arrangement 10 can be a single conduit element 300 , or two or more line elements 300 , Eg include 10 or 100 line elements.

According to 2 is every conduit element 300 individually with the contact surface 120 respectively. 130 contacted. Likewise, however, a plurality of line elements can also be contacted together with a contact surface in that a plurality of line elements have a common end or both ends of a plurality of line elements are designed as common ends. The layer 150 is in for reasons of simplification 2 not shown.

According to a further embodiment, not shown, the contact spring arrangement consists of a spring element and a line element. The line element may be arranged on a contact surface, or the line element may be arranged on two contact surfaces.

3 shows a cross-sectional view of the contact spring assembly 10 as well as a contact 50 to explain the operation of the contact spring assembly. The contact 50 has a groove 500 with a height H2 up. The height H2 is less than the height of the contact spring. When inserting the contact spring arrangement 10 in the groove 500 becomes the spring element 200 and the conduit element 300 compressed. In the elastic material of the spring element 200 a compressive force F is generated, due to which a frictional connection between the conduit element 300 and an upper electrically conductive contact surface 510 comes about. Likewise, it comes to a non-positive connection between the metallic layer 170 the contact spring arrangement 10 and a lower contact surface 520 the contact 50 , If the lower contact surface 520 is formed of an electrically conductive material, so it is also a conductive connection.

The contact spring arrangement 10 can out of the groove 500 be pulled out. Then the spring element returns 200 back to the original, in 1 shown back shape, wherein the spring element 200 also the line element 300 back to the original shape.

The contact spring arrangement 10 may preferably be formed in an edge region of the substrate, ie between at least one outer edge of the substrate 100 and the spring element 200 are no active semiconductor devices arranged. As a result, the insertability of the contact spring arrangement 10 in the contact 50 improved.

4 shows a flowchart illustrating the process order of a first exemplary method for producing a contact spring assembly.

In a first process step, the substrate 100 with at least one contact surface 130 provided. Then the spring element 200 on the substrate 100 educated. This can be done by various techniques, which are described below with reference to FIGS 5 to 9 be explained.

5 shows a partially finished contact spring assembly 10 according to the first embodiment of the invention, wherein the spring element 200 using stencil or screen printing technique on the substrate 100 is applied. For this purpose, the elastic material is painted through a fabric surface with stencil attached thereto. The template causes the material to pass through the tissue and onto the substrate only in the non-stenciled areas. There, the elastic material is solidified, for example by means of a heat treatment. The top 220 of the spring element 200 has in cross-section an arcuate course, ie the height of the spring element decreases from the lateral edges 230 . 240 steadily increasing towards the middle region of the cross section. The top 220 has a substantially convex profile when viewed in cross-section. Near the side edges 230 . 240 is the top 220 according to 5 but concave shaped. This surface course results because the material is applied in non-solidified state. By using materials with suitable surface tension and viscosity, other cross sections of the spring element can be used 200 For example, flatter or steeper edges are achieved, so the spring element can be formed, for example, with completely convex upper surface.

6 shows a partially finished contact spring assembly 10A according to a second embodiment of the invention with a spring element 200A as a prefabricated element on the substrate 100 , was applied. The substrate 100 is that in 1 described substrate. The attachment of the prefabricated element can be done for example by gluing. Alternatively, the adhesion of the prefabricated element may be sufficient for attachment. The element 200A has a convex cross section. At the side edges 230A and 240A meets the top 220A of the spring element 200A at an angle α to the bottom 210A of the spring element 200A , According to 6 the angle α is a right angle. As a result, a large spring height can be achieved in a particularly small space. Alternatively, the angle α may be, for example, an acute angle, for example, 5 ° <α <89 °. Likewise, the prefabricated spring element may have other cross sections, for example triangular or stepped cross sections. Alternatively, the spring element may be formed as a hollow body, for example as a tube.

7 shows a perspective view of the prefabricated spring element 200A according to 6 , The spring element 200A has a planar base 210A and a constant cross section over the entire length L of the spring element 200A ,

8th shows a partially finished contact spring assembly 10B according to a third embodiment of the invention with a spring element 200B , which consists of three superposed layers of material. The substrate is that with respect to the 1 described substrate 100 , The material layers can be applied, for example, as films one after the other onto the substrate and structured there, or they can be applied as already prefabricated, structured stacks. The material layers can be structured, for example, by laser ablation or by photochemical methods. Alternatively, only two, or four or more layers of material can be arranged one above the other to form the spring element.

According to 8th is a first layer of material 250B with a first width B1 on the substrate 100 arranged. On the first material layer 250B is a second layer of material 260B arranged with a second width B2. A third layer of material 270B with a third width B3 is on the second material layer 260B arranged. The widths of the material layers decrease from the first material layer 250B to the third material layer 270B from, ie B1>B2> B3. The spring element 200B therefore has a width that gradually decreases as the distance from the substrate increases.

Preferably, the material layers 250B . 260B and 270B the same thickness and made of the same material. Alternatively, however, films of different materials and / or with different thicknesses can be combined with each other as desired. At least one layer of material may be formed of elastic material.

9 shows a partially finished contact spring assembly 10C according to a fourth embodiment of the invention, wherein further contact surfaces 180 . 190 with respect to the 1 described substrate are formed. On the substrate 100 continue to be with respect to the 8th described spring element 200B and a semiconductor chip 400 arranged. The semiconductor chip 400 can at its bottom eg with the substrate 100 be glued. A slide 250 is flat over the substrate and over the chip 400 arranged. The foil 250 is structured in subranges to underlying areas of the chip 400 and the substrate 100 , such as the contact surfaces 180 . 190 and connection surfaces 410 and 420 of the chip 400 expose. The foil 250 forms, for example, an insulation for a metallization to be formed in a later step. The foil 250 is also in the area of the spring element 200B trained and forms there the layer 250B , The spring element 200B further comprises the film layer 260B and 270B as related to 8th described. Alternatively, the film could 250 also the material layer 260B or 270B form. The film may consist of any thermoplastics, thermosets and mixtures thereof. Preferably, a film of a plastic material on polyimide (Pi), polyethylene (PE), polyphenol, polyetheretherketone (PEEK) - and / or epoxide-based is used. The film may have an adhesive layer to improve adhesion to the surface. The film may have a thickness of 10 .mu.m to 500 .mu.m, preferably the thickness of the film is 25 .mu.m to 150 .mu.m. The foil 250 For example, it can be laminated onto the substrate and then structured. The lamination can take place, for example, under vacuum with a vacuum press, by vacuum deep drawing, hydraulic vacuum pressing, vacuum pressure pressing or similar laminating methods, eg at a pressure of -850 mbar. The lamination takes place for example at temperatures of 100 ° C to 250 ° C and a pressure of 1 bar to 10 bar. For better attachment of the films, an adhesive can be used. The structuring of the film can take place, for example, by means of laser ablation or photochemical processes.

Regarding 4 In a next method step, the line element is formed on the at least one contact surface of the substrate and over the spring element. This can be done by various techniques, which are described below with reference to FIGS 10 to 12 be explained.

10 shows a cross-sectional view of the contact spring assembly 10 , wherein the conduit element 300 by means of a bonding process at its ends 310 . 320 was placed on the substrate. The substrate is that with respect to the 1 described substrate 100 , The pipe element 300 may for example consist of a bonding wire or a flat ribbon. The conduit element may be, for example, by means of thermocompression bonding, thermosonic ball wedge bonding, ultrasonic wedge-wedge bonding or other suitable bonding methods on the substrate 100 to be ordered. According to 10 touches the conduit element 300 with respect to 1 described spring element 200 Not. However, this is not necessary, but the line element 300 the spring element 200 partially touch or lie flat on this.

11 shows a cross-sectional view of a contact spring assembly 10D according to a fifth embodiment of the invention. In this embodiment, a conduit element 300D by means of electrodeposition on the substrate 100 and over the spring element 200 , which with reference to the 1 have been described. For this purpose, first a mask layer can be formed on the substrate. The masking layer is patterned by conventional methods so that the masking layer is removed in the areas where the conducting element 300D should be trained. Subsequently, a thin metallic nucleation layer may be formed on the cap layer and in the exposed areas. This can be done, for example, by physical or chemical deposition. For example, the nucleation layer may be formed by physical vapor deposition (PVD) or chemical vapor deposition (CVD). Alternatively, the nucleation layer can also be deposited over the substrate in a planar manner and patterned into the desired shape by means of a mask. After removing the mask layer, the nucleation layer remains in the areas in which the line element is to be formed and can be reinforced by electrodeposition with an electrically conductive layer, whereby the line element 300D arises. The pipe element 300D is preferably flat on the spring element 200 on.

12 shows a cross-sectional view of a contact spring assembly 10E according to a sixth embodiment, with reference to the 1 described substrate 100 further contact surfaces 180 . 190 includes and on the substrate 100 furthermore a semiconductor chip 400 is arranged. This can be glued, for example, on its underside with the substrate. The contact spring arrangement 10E includes the spring element described above 200 and a conduit element 300E , The foil 250 as they relate to 9 is partially above the substrate 100 and over the semiconductor chip 400 arranged. The foil 250 points at least in the area of the contact surfaces 120 . 130 . 140 . 180 and 190 as well as in the area of the connecting surfaces 410 and 420 of the semiconductor chip 400 Recesses on. A metallic layer 430E is over the slide 250 arranged and provides an electrical connection between the pad 410 respectively. 420 of the chip 400 and the contact surfaces 180 respectively. 190 of the substrate. According to this embodiment, the conduit element 300E formed in the same process step, in which also the metallic layer 430E is trained. The metallic layer 430E and the conduit element 300E may preferably be made of the same material. The metallic layer is preferred 430E and the conduit element 300E formed by electrodeposition, in particular in a common process step, as above with respect to the line element 300D in 11 has been described. According to this embodiment, the spring element 200 formed by screen printing and has an arcuate top. In an embodiment, not shown, but also a spring element with a step-shaped tapered cross section, as in 9 shown to be used. In a further embodiment, not shown, the spring element may consist of several layers, in particular, a portion of the film 250 form a layer of the spring element.

In other embodiments, not shown, alternatively, the prefabricated spring element 200A with the above-described line element 300 be combined that was produced by bonding method, or with the galvanically formed line element 300D according to 11 , Likewise, alternatively, the step-shaped tapered spring element 200B according to 8th and 9 with the bonded conduit element 300 or with the galvanically formed line element 300D be combined.

13 shows a flowchart illustrating the process order of a second exemplary method for producing a contact spring assembly. In this method, the line element is formed in front of the spring element on the substrate.

14 shows a contact spring arrangement 10F according to a seventh embodiment, after forming a conducting element 300F above that with respect to the 1 described substrate 100 , The pipe element 300F For example, by referring to the 10 to 12 described method can be formed, preferably by means of bonding. The pipe element 300F can consist of a bonding wire or a ribbon. Alternatively, the conducting element may contain a galvanically deposited material, for example by forming the conducting element over a dummy structure and subsequently removing the dummy structure.

The pipe element 300F contacts the contact surfaces 120 and 130 of the substrate 100 , At this time of manufacture, a cavity remains 600 between the conduit element 300F and the substrate 100 in the area between the contact surfaces 120 and 130 ,

In a next step, as in 15 shown the cavity 600 with an elastic material for forming the spring element 200F refilled. For this purpose, a subsequent filling process is used, such as a capillary underfill, in which a flowable material in the cavity 600 is introduced and completely fills it due to capillary forces. The flowable material can then be cured eg by a tempering process.

The 16 and 17 show perspective views of contact spring assemblies 10G and 10H according to an eighth and ninth embodiment. These embodiments use the above 1 described substrate 100 , An essential difference from the preceding embodiments is that the conduit element 300G respectively. 300H the substrate 100 only on one side of the spring element 200 contacted. The pipe element 300G respectively. 300H contacted with a first end 310G respectively. 310H the second contact surface 130 of the substrate 100 , The pipe element 300G respectively. 300H extends from the second contact surface 130 to the highest point of the spring element 200 , Alternatively, the conduit element can also be up to the second contact surface 130 opposite side 280 of the spring element, without the substrate 100 touch or contact on this page.

At the line elements 300G and 300H they can be bonding wires, flat strips or galvanically deposited metal. Likewise, also a different number of line elements 300G respectively. 300H as in 16 respectively. 17 shown used.

In further embodiments, not shown, in the 1 to 4 shown and explained above contact spring assemblies 10 . 10A . 10B . 10C . 10D . 10E . 10F Use line elements that only contact the substrate on one side.

18 shows a perspective view of a contact spring arrangement 10I consisting of several contact spring arrangements 10G on a common substrate 100 consists. These can, as shown, next to each other, ie be arranged in the longitudinal direction of the line elements. Alternatively, the contact spring arrangements can also be arranged one behind the other, ie along a line transversely to the longitudinal direction of the line elements or offset as desired. It is also conceivable to group other embodiments of contact spring arrangements described here into a combination, wherein identical or different embodiments can be combined with each other.

For example, contact spring assemblies having different spring elements may be combined together, e.g. Contact spring arrangements with a stepped tapered spring element and an arcuate spring element. Likewise, contact spring assemblies having different conductive elements may be combined together, e.g. For example, a contact spring arrangement with a bonded conducting element can be combined with a contact spring arrangement with a galvanically formed conducting element. Alternatively, a contact spring arrangement whose line element is arranged only on a contact surface can be combined with a contact arrangement in which the line element is arranged on two contact surfaces.

If a plurality of contact spring assemblies are disposed on a substrate, they may form a common terminal, alternatively, the contact spring assemblies may also provide different terminals for multiple modules or boards.

While the invention has been further illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims (15)

Contact spring arrangement comprising: - a substrate ( 100 ) with at least one contact surface ( 130 ), - a spring element ( 200 ) on the substrate ( 100 ), and - a conduit element ( 300 ) at the first contact surface ( 130 ) and over the spring element ( 200 ) is arranged. Contact spring arrangement according to claim 1, wherein - the spring element ( 200 ) consists of elastic material. Contact spring arrangement according to claim 1 or 2, wherein - the spring element ( 200 ) an upper side ( 220 ) and the top ( 220 ) has an arcuate profile in cross-section. Contact spring arrangement according to claim 1 or 2, wherein - the spring element ( 200B ) has a width (B1, B2, B3) which increases with increasing distance from the substrate ( 100 ) stepped down. Contact spring arrangement according to one of the claims 1 to 4, in which - the spring element ( 200 ) at least a first material layer ( 250B ) and one above the first material layer ( 250B ) arranged second material layer ( 260B ) having. Contact spring arrangement according to claim 5, further comprising - a semiconductor chip ( 400 ), which is arranged on the substrate, and - a film layer ( 250 ), which on portions of the semiconductor chip ( 400 ) and on subregions of the substrate ( 100 ), wherein - the first material layer ( 250B ) or the second material layer ( 260B ) from the film layer ( 250 ) is trained. Contact spring arrangement according to one of the claims 1 to 6, in which the line element ( 300 ) flat on the spring element ( 200 ) rests. Method for producing a contact spring arrangement comprising the steps of: - providing a substrate ( 100 ) with at least one contact surface ( 130 ), - forming a spring element ( 200 ; 200F ) on the substrate ( 100 ), and - forming a conduit element ( 300 ; 300F ), so that after the formation of the spring element ( 200 ; 200F ) and the line element ( 300 ; 300F ) the conduit element ( 300 ; 300F ) at the at least one contact surface ( 130 ) and over the spring element ( 200 ; 200F ) is arranged. Method according to claim 8, wherein - the spring element ( 200 ) by means of stencil or screen printing on the substrate ( 100 ) is formed. Method according to claim 8 or 9, in which - for forming the spring element ( 200 ) a first material layer ( 250B ) on the substrate ( 100 ) and at least one second material layer ( 260B ) on the first material layer ( 250B ) is arranged. Method according to claim 8 or 9, wherein - the conduit element ( 300 ; 300F ) before or after the spring element ( 200 ; 200F ) is formed. Method according to one of the claims 8 to 11, wherein furthermore a semiconductor chip ( 400 ) on the substrate ( 100 ) is arranged, and in which the formation of the spring element ( 200 ) comprises the steps of: - applying a film ( 250 ) on the substrate ( 100 ) and on the semiconductor chip ( 400 ), and - structuring the film ( 250 ). Method according to claim 12, in which - the film ( 250 ) is laminated under vacuum. Method according to claim 12 or 13, wherein - the conduit element ( 300D ) is formed during a process step in which an electrically conductive connection ( 430D ) between the semiconductor chip ( 400 ) and the substrate ( 100 ) will be produced. Method according to one of the claims 8 to 14, wherein the conduit element ( 300D ) is formed using electrodeposition. Method according to one of the claims 8 to 13, wherein the conduit element ( 300 ) by means of a bonding process on the at least one contact surface ( 130 ) is arranged.

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