DE102015109953A1 - Production of electronic components - Google Patents

Abstract

The invention relates to a method for producing electronic components. The method comprises providing a metal foil, arranging the metal foil on an auxiliary carrier, and structuring the metal foil arranged on the auxiliary carrier into separate connection elements. Furthermore, provision is made for forming a shaped body having recesses on the auxiliary carrier and the connecting elements, arranging semiconductor chips on connecting elements in the recesses of the shaped body, removing the auxiliary carrier and severing the shaped body to form individual electronic components. The invention further relates to an electronic component.

Description

The invention relates to a method for producing electronic components. The invention further relates to an electronic component.

Electronic components such as optoelectronic components for generating light radiation can be implemented in the form of QFN packages (Quad Flat No Leads). In a conventional method of manufacturing such devices, a metallic lead frame is provided which may be formed of copper and provided with a metallic coating and which is overmolded with a molding compound to form a molding. The lead frame has connection surfaces and connection bars connecting the connection surfaces (so-called tie bars or support bars). The molded body is formed with recesses over which the connection surfaces are exposed on a front side. At these locations, semiconductor chips are arranged on the pads and electrically connected to the pads. The backs of the pads also remain free, making the manufactured devices suitable for surface mounting. After arranging the semiconductor chips, further processes are carried out, such as filling the recesses with a potting compound and singulating the component composite produced in this way.

When separating takes place a severing of the molding and the connecting webs of the lead frame, so a severing of an inhomogeneous combination of materials. This process is carried out by means of a sawing process. The inhomogeneous combination of materials limits the possible sawing speed to produce clean outer edges of the components. Therefore, the cutting is associated with a high time and cost.

When separating the components, it may possibly come to a smearing of material of the connecting webs. This creates the risk of short circuits. Furthermore, the connecting webs in the isolated components extend to the outer sides, and are therefore prone to corrosion.

It is also disadvantageous that gaps can arise between the connecting webs and the molded body in the case of a thermomechanical load as well as under a chemical load. Due to the connecting webs reaching to the outside, it is therefore possible for harmful substances which impair the components (for example flux, solder, etc.) to penetrate into the interior of the components via the gaps.

The object of the present invention is to provide a solution for an improved production of electronic components.

This object is solved by the features of the independent claims. Further advantageous embodiments of the invention are specified in the dependent claims.

According to one aspect of the invention, a method for producing electronic components is proposed. The method comprises providing a metal foil, arranging the metal foil on an auxiliary carrier, and structuring the metal foil arranged on the auxiliary carrier into separate connection elements. Furthermore, provision is made for forming a shaped body having recesses on the auxiliary carrier and the connecting elements, arranging semiconductor chips on connecting elements in the recesses of the shaped body, removing the auxiliary carrier and severing the shaped body to form individual electronic components.

In the method, separate metallic connection elements are formed by arranging a metal foil on a temporary auxiliary carrier and subsequently subjecting the metal foil to structuring. Separately means that the connection elements are spatially separated from each other and not interconnected by material of the connection elements or the underlying metal foil.

Following the patterning of the metal foil on the submount, further steps, i. Forming a shaped body with recesses, arranging semiconductor chips on connecting elements in the recesses of the shaped body, removing the subcarrier and separating the component composite produced in this way carried out. These steps can be performed in the above order.

Deviating from this, a different order can be provided. For example, the removal of the subcarrier can not be performed after, but before arranging semiconductor chips on connection elements. This will be discussed in more detail below.

After the structuring of the metal foil, the separate connecting elements can be held or carried by the auxiliary carrier so that the further processing or the formation of the shaped body can take place. The subcarrier can also be used for a backside sealing of the Provide connecting elements in the formation of the molding, so that contamination of backs of the connection elements can be avoided.

The formation of separate connection elements instead of the use of a metallic lead frame with connecting surfaces and connecting webs makes it possible to separate only the shaped body for separating the component composite. In this way, this process can be done easily and quickly. As a result, a high production throughput and consequently a cost savings are possible.

Further, the component composite can be realized with a high packing density due to the formation of the separate terminal members instead of the use of a lead frame. This also leads to a cost saving.

A severing of only the shaped body further leads to the fact that the isolated electronic components have no reaching to the outside connecting webs. Therefore, the devices may be corrosion resistant and insensitive to short circuits. Also, the components can have a high density, so that penetration of harmful substances into the component interior can be avoided.

In the following, further possible embodiments and details of the method and of the electronic components produced by means of the method will be described in more detail.

In one embodiment, the cutting of the shaped body for separating the component composite by sawing takes place. This is possible with a high sawing speed of, for example, up to 500mm / s. In a conventional manufacturing process, however, sawing is carried out by the inhomogeneous material combination (shaped bodies, connecting webs) present here at a much lower sawing speed, for example of only about 50 mm / s.

For the cutting of the shaped body, other processes may also be considered instead of sawing. Possible are for example a laser cutting or a water jet cutting.

The electronic components produced may be so-called QFN packages (Quad Flat No Leads), which are suitable for surface mounting (SMT, Surface Mounting Technology). In this case, the metallic connection elements can be exposed on a rear side of the components. With the help of the connection elements, the components can be soldered, for example, to a printed circuit board. Due to the underlying structuring of the metal foil, the connection elements can be realized in the form of laminar layer elements or bonding pads.

The manufactured electronic components may furthermore be single-chip components. In this case, the components may in each case have a housing body having a recess which emerges from the molded body, a plurality of or two separate and rearwardly exposed connection elements, and a semiconductor chip. The semiconductor chip can be arranged in the recess of the housing body on a connection element.

The removal of the auxiliary carrier can, as indicated above, be carried out after forming the shaped body and before arranging semiconductor chips on connecting elements. After forming the shaped body, the connecting elements can be held together via the shaped body, so that the auxiliary carrier can be dispensable with respect to this function. The removal of the auxiliary carrier can also be carried out after the arrangement of semiconductor chips on connecting elements and before the cutting of the shaped body.

The provided metal foil may have a thickness in a range of 30μm to 500μm.

In a further embodiment, the metal foil provided has a metallic base layer which is coated with a metallic layer. The resulting metallic connection elements are coated in a corresponding manner with the metallic layer. Due to the coating, the connection elements can be solderable and suitable for connecting bonding wires. The base layer may be, for example, a layer or foil made of copper. The metallic layer arranged thereon may be formed as a single layer or as a multilayer in the form of a stack of several partial layers. The coating can be carried out by means of one or, in the case of a multilayered embodiment, by means of a plurality of successive metallization processes.

With regard to an embodiment of the connection elements with such a solderable coating, the following embodiment may also be considered. In this case, the connecting elements are coated with a metallic layer after the formation of the shaped body and before the arrangement of semiconductor chips. Coating takes place in such a way that only the connection elements are coated with the metallic layer. This can be done with the help of one, or in a multi-layered design with the help of several successive metallization be performed. The procedure of forming the molded body prior to forming a solderable coating makes it possible to achieve good adhesion between the molded body and the terminal members. It is also possible for any gaps between the connection elements and the shaped body to be closed by the coating. As a result, the electronic components can be manufactured in a reliable manner with a high density. Before coating the connection elements, the auxiliary carrier can be removed.

With regard to the aforementioned embodiment, the provided metal foil, which is patterned on the auxiliary carrier into the separate metallic connection elements, may be an uncoated metallic foil of, for example, copper. In this way, the presence of a good adhesion between the molded body and the connecting elements can be further promoted.

Possible examples of the plating methods given above and used for coating are electroplating or electroless plating.

In a further embodiment, the auxiliary carrier is a carrier film. The carrier film may be a plastic film which has an adhesive layer on one side. In this embodiment, arranging the metal foil on the auxiliary carrier may comprise laminating the carrier foil to the metal foil. The use of a carrier film makes it possible to carry out the process in a simple and cost-effective manner. Also can be achieved with the help of a carrier film, a reliable back sealing of the connection elements.

In a further embodiment, the structuring of the metal foil into the separate connection elements is carried out with the aid of an etching process. This can be a wet-chemical etching process. With regard to such a process, an etch-resistant carrier film may be used as a subcarrier. For example, it is possible to use a film of polyimide or polyethylene terephthalate which has an adhesive layer on one side.

Before patterning the metal foil by etching, an etching mask such as a photoresist mask may be formed on the metal foil. It is also possible to carry out the etching process using mechanical masking of the metal foil.

In a further embodiment, forming the shaped body with the recesses comprises performing a molding process. In this process, a suitable molding compound is applied to the auxiliary carrier and the connecting elements located thereon. The molding compound may comprise a plastic material, for example an epoxy material or silicone material. Furthermore, the molding compound may comprise a particulate filler contained therein, for example, SiO 2 particles and TiO 2 particles. As a result of the SiO 2 particles, the shaped body can have a small coefficient of thermal expansion, and in this way can be adapted to the thermal expansion coefficients of the connecting elements. With the help of TiO2 particles, a white coloration of the molding can be achieved. After the formation of the molded body, an additional process for removing residues of the molding compound on front sides of the connecting elements may optionally be performed (deflashing).

The molding process may be a transfer molding process. Also possible is a film-assisted transfer molding process (Film Assisted Transfer Molding). Here, the mandrels of a tool part of a Moldwerkzeugs are sheathed for better sealing with a film. In this way it can be achieved that the connection elements are not covered with high reliability front side with unwanted residues of the molding compound.

The shaped body can be formed in such a way that in each case at least two connecting elements on a front side are partially exposed over each recess of the shaped body. Within each recess may be present between each two connecting elements a web-shaped part of the molding, which may have a smaller thickness than a surrounding recess of the associated recess of the molding.

With regard to the above-mentioned production of single-chip components, a corresponding semiconductor chip can be arranged in each recess of the molded body.

For the semiconductor chips used, different configurations may be considered. For example, it is possible for the semiconductor chips to have a front-side contact and a back-side contact. In this case, a semiconductor chip placed in a recess of the molded body can be electrically and mechanically connected to the rear contact with a connection element. A compound may be formed via a suitable bonding layer, for example a solder layer, a layer of an electrically conductive adhesive or a sintered layer of, for example, silver, getting produced. The front-side contact of a semiconductor chip can be connected to a further connection element via a connection structure, for example a bonding wire.

Alternatively, semiconductor chips may be used which, for example, have two rear side contacts or two front side contacts. In the first variant, a semiconductor chip with the two rear side contacts can be arranged on two connection elements and connected to them via a corresponding connection layer (for example a solder layer, a layer of a conductive adhesive or a sintered layer of, for example, silver). In the second variant, a semiconductor chip can be arranged on a connection element, one of the two front side contacts can be connected to a further connection element via a connection structure or a bonding wire to the same connection element and the other front side contact via a further connection structure or a further bonding wire. Alternatively, three connection elements may be provided for one semiconductor chip, of which two connection elements are used for connection to the front side contacts, and a further connection element is used for fastening the semiconductor chip.

In a further embodiment, a potting compound is introduced into the recesses of the shaped body. This step can be carried out after arranging semiconductor chips on connecting elements in the recesses of the shaped body, as well as before a removal of the auxiliary carrier. With the help of the potting compound, the semiconductor chips can be encapsulated and thereby protected from external influences.

When filling the recesses of the molding, the auxiliary carrier can also provide for a backside sealing of the connection elements, so that despite possibly present gaps between the molding and the connection elements contamination of back sides of the connection elements can be avoided.

In a further embodiment, the electronic components produced are optoelectronic components. In a corresponding manner, optoelectronic semiconductor chips are arranged on connecting elements in the recesses of the shaped body.

With respect to the aforementioned embodiment, optoelectronic semiconductor chips may be used, which are designed to generate light radiation. These can be light-emitting diode chips.

When using optoelectronic radiation-emitting semiconductor chips, it may also be considered to introduce a potting compound into the recesses of the shaped body, which has a radiation-permeable potting or plastic material, for example a silicone material. The potting compound may additionally comprise embedded in the potting material phosphor particles for radiation conversion. In this way, the potting compound can convert at least part of a light radiation generated by the semiconductor chips during operation.

In another embodiment, the method includes forming recesses in the metal foil prior to placing the metal foil on the submount. The recesses are formed on a first side of the metal foil. In structuring the metal foil into the separate connection elements, material of the metal foil is removed starting from a second side of the metal foil opposite the first side in the region of the depressions. This takes place in such a way that the connection elements have an anchoring structure for anchoring the shaped body at the edge. In this way, a good adhesion or connection between the molded body and the connecting elements can be achieved, since due to the anchoring structure, a mechanical positive connection can arise.

Before structuring into the connecting elements, the metal foil provided with the depressions can be arranged with the first side on the auxiliary carrier. The first and second sides of the metal foil may be opposite major sides of the metal foil.

The recesses may be continuous and formed in the form of a grid in the metal foil. In this way, regions of the metal foil enclosed by the depressions can be formed, which can have corresponding shapes to the subsequently formed connection elements.

The formation of the depressions can be carried out with the aid of an etching process.

With regard to the anchoring structure, the structuring of the metal foil into the connection elements can take place in such a way that material is removed in removal regions which have a smaller width than the previously formed depressions. In this way, the separate connection elements produced by structuring can have a step shape at the edge, which can serve as anchoring structure.

Further features and details for the method may also be used. For example, the method can also be carried out in such a way that multichip components are produced which have a plurality of semiconductor chips. Such components may, for example, in each case have a housing body which emerges from the molded body and has a plurality of separate recesses in which semiconductor chips can be arranged on corresponding connection elements.

It is also possible to manufacture multichip components which each have a housing body which emerges from the molded body and has a common recess for a plurality of semiconductor chips. In this case, a plurality of semiconductor chips can be arranged on individual, or even on one or more common connection elements. Furthermore, a plurality of semiconductor chips placed in a common recess of the molded body can be electrically connected to one another, for example with the aid of bonding wires.

With regard to the auxiliary carrier used, further embodiments are also conceivable. For example, as a subcarrier, a carrier foil can be used, which is or is arranged on a solid support in order to provide a higher stability. The carrier film may be formed as indicated above. The solid support can be, for example, a metal-based support, a glass support or a plastic-based support. In this case, the arrangement of the carrier film on the solid support can be carried out before or after the arrangement of the metal foil on the carrier film. An attachment of the carrier film on the solid support can be realized by means of an adhesive. In this context, a double-sided adhesive film between the support film and the solid support may further be used. After the formation of the molding or after the filling of a potting compound, the carrier film and the solid support can be removed.

According to a further aspect of the invention, an electronic component is proposed, which is produced by carrying out the above-mentioned method or one or more embodiments of the method. The component has a housing body which has emerged from the molding by cutting. Furthermore, the component has a circumferential lateral surface, which is formed exclusively by the housing body, and thus the molding compound. On the lateral surface zoom reaching connecting webs are therefore not available. Therefore, the device may be corrosion resistant and insensitive to short circuits. This embodiment is a consequence of the formation of separate connection elements and the severing of only the shaped body.

The lateral boundary or edge region of the component falls under the expression lateral surface used here. The lateral surface, which is present between a front and a rear side of the component, can be composed of all the lateral outer sides or side flanks / surfaces of the component. The component produced according to the method may, for example, in plan view, have a rectangular contour or, as a whole, a parallelepiped shape, so that the lateral surface can be composed of four side walls or side surfaces which adjoin one another at right angles.

It should be noted that aspects and details mentioned above with reference to the manufacturing method can also be applied to the electronic component. In this regard, the housing body of the device may have at least one recess. The component may have at least two separate terminal elements which are exposed on a rear side, and at least one semiconductor chip. The semiconductor chip can be arranged in or in a recess of the housing body on at least one metallic connection element. The at least one recess can also be filled with a potting compound. The component may be a single-chip component or else a multi-chip component. Furthermore, the component can be an optoelectronic component.

The advantageous embodiments and further developments of the invention explained above and / or reproduced in the subclaims can be used individually or else in any desired combination with one another except, for example, in cases of clear dependencies or incompatible alternatives.

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 exemplary embodiments, which are explained in more detail in connection with the schematic drawings. Show it:

1 to 12 a possible process sequence for the production of electronic components, in which a metal foil is arranged on a carrier foil and structured into separate connection elements, a shaped body with recesses is formed, semiconductor chips are arranged in the recesses on connection elements, the recesses are filled with a potting compound and a singulation is performed becomes;

13 to 19 Another possible procedure for the production of electronic components, in which, in contrast to the procedure of the 1 to 12 Connection elements are metallized after forming the shaped body;

20 to 28 Another possible procedure for the production of electronic components, in which, in contrast to the procedure of the 1 to 12 prior to arranging the metal foil on the carrier foil depressions are formed in the metal foil; and

29 to 36 Another possible procedure for the production of electronic components, in which, in contrast to the procedure of the 20 to 28 Connection elements are metallized after forming the shaped body.

Possible embodiments of a method for producing electronic components will be described with reference to the following schematic figures. In this case, known processes can be carried out from semiconductor technology and from the production of electronic components, and customary materials can be used in these areas, so that this is only partially discussed. In the same way, the components can be manufactured in addition to components shown and described with other components and structures. It is further noted that the figures are merely schematic in nature and are not to scale. In this sense, components and structures shown in the figures may be exaggerated or oversized for clarity.

The 1 to 12 show a possible method for manufacturing electronic components 100 , With the components 100 These are surface-mountable single-chip components, which are each realized in the form of a QFN package (Quad Flat No Leads). Every component 100 has a single semiconductor chip 150 on. With the components 100 can be radiation-emitting optoelectronic components 100 act. In this embodiment, optoelectronic semiconductor chips are used 150 for use, which are designed for generating radiation.

In the method, a composite of contiguous components is produced, which subsequently in the components 100 is isolated. The 1 to 12 illustrate the method by means of lateral representations and supervisory presentations. It should be noted that instead of the conditions shown in the figures, a much larger bond can be made. The figures can be understood in this sense as a partial representation of the process.

In the process, a metal foil 110 provided in which 1 shown from the side. A thickness of the metal foil 110 can be in a range of 30μm to 500μm. The metal foil 110 has a metallic base layer 111 on which front and back with a metallic layer 112 is coated. The layer 111 may be formed of Cu, for example. With the help of the arranged thereon metallic layer 112 can be achieved that metallic connection elements 131 . 132 , which in the process by structuring the metal foil 110 be formed (see the 3 . 4 ), a solderable and for connecting bonding wires 151 have suitable surface.

The metallic layer 112 may be formed in one layer of Ag, for example. Also possible is a multi-layered embodiment, not shown, in the form of a stack of several partial layers, for example of Ni, Ag or Ni, Pd, Au or Ni, Au. The metallic layer 112 can with the help of one or more consecutive metallization on the layer 111 be generated. An example of a metallization process is electroplating.

The provided metal foil 110 will, as in 2 is shown on serving as a subcarrier carrier film 120 arranged. This process is carried out by laminating the carrier film 120 on the metal foil 110 , In the carrier film 120 it is a plastic film which has a non-illustrated adhesive layer on one side. This page is the carrier film 120 on the metal foil 110 glued.

With regard to a subsequent etching process is the carrier film 120 etch resistant. For this purpose, it may be in the carrier film 120 For example, be provided with an adhesive layer film of PI (polyimide) or PET (polyethylene terephthalate).

In the etching process, the on the support film 120 arranged metal foil 110 , as in 3 from the side and in 4 is shown in the plan, in separate flat connection elements 131 . 132 structured with different lateral dimensions. The metallic connection elements 131 . 132 are spatially separated, and not by material of the connection elements 131 . 132 or the underlying metal foil 110 connected with each other.

As in the supervisory presentation of 4 is illustrated, the connection elements 131 . 132 with a rectangular shape and in the form of a grid of rows and columns on the carrier film 120 be formed. The connection elements 131 . 132 have a planar structure, and are therefore referred to below as pads (bond pads). Furthermore, the larger pads 131 as first connection surfaces 131 , and the smaller pads 132 as second connection surfaces 132 designated. For each of the components manufactured in the process 100 Each is a pair of first and second pads 131 . 132 intended.

The etching process is a wet-chemical etching process which is carried out with a suitable etchant. This has the consequence that the metallic pads 131 . 132 on the edge the in 3 have indicated isotropic rounded Ätzflanken. Before the actual structuring of the metal foil 110 For example, an etch mask, for example a photoresist mask, may be applied to the metal foil 110 trained and removed after etching again from this. To protect areas of the metal foil 110 which are not to be attacked by the etchant, alternatively, a mechanical masking can be used (not shown).

Forming the separate pads 131 . 132 instead of the conventional use of a ladder frame with pads and tie bars offers the possibility of the pads 131 . 132 form with small distances to each other. As a result, the component composite can be manufactured with a high packing density.

After forming the pads 131 . 132 will, as in 5 from the side and in 6 is shown in the plan, a contiguous molded body 140 on the carrier foil 120 and the pads thereon 131 . 132 educated. For this purpose, a molding process, for example a transfer molding process (transfer molding) is carried out, in which a molding compound (molding compound) on the carrier film 120 and the connection surfaces 131 . 132 is applied. This process is performed using a tool, not shown. In the formation of the shaped body 140 can the carrier film 120 a back-sealing of the connection surfaces 131 . 132 effect, leaving the pads 131 . 132 not covered on the back with the molding compound.

The molding compound may comprise a plastic material, for example an epoxy material or silicone material. The molding compound may further be highly filled with a particulate filler (not shown). The filler may be SiO 2 particles and TiO 2 particles. Due to the SiO 2 particles, the shaped body 140 have a small coefficient of thermal expansion, and in this way the thermal expansion coefficient of the metallic pads 131 . 132 be adjusted. Due to the TiO2 particles, the molded body 140 have a white color. After application, the molding compound can be cured.

The molded body 140 is with cavities or recesses 141 formed, over which the connection surfaces 131 . 132 are exposed on a front side. Every recess 141 is a pair of first and second pads 131 . 132 assigned so that they are exempted front. For this purpose, the recesses 141 according to the grid of the connection surfaces 131 . 132 educated. At the edge of the recesses 141 are the connection surfaces 131 . 132 on the front part of the molding 140 covered.

The recesses 141 point in a direction away from the pads 131 . 132 widening shape with an angle to the connection surfaces 131 . 132 extending side walls, so that the recesses 141 in the finished components 100 can serve as reflectors. Seen from above, the recesses can 141 , as in 6 is shown to have a rectangular contour with rounded corners.

The molded body 140 is also located next to or between the connection surfaces 131 . 132 , And reaches at these points to the carrier film 120 approach. These include back sections of the recesses 141 surrounding and side walls of the recesses 141 forming part of the molding 140 , as well as between the connection surfaces 131 . 132 existing bridges 142 of the molding 140 , The bridges 142 have a smaller thickness than the recesses 141 surrounding part of the molding 140 , As in 5 shown, the webs can 142 have the same thickness as the pads 131 . 132 ,

It is possible that the connection surfaces 131 . 132 after performing the molding process on the front side undesirable residues of the molding compound (not shown). Such residues can subsequently be removed in a further process (deflashing).

This can optionally be avoided by forming the molding 140 using a film assisted transfer molding process (Film Assisted Transfer Molding). Here, the mandrels of a tool part of the tool used for a better Sealing coated with a foil. In this way it can be achieved that the connection surfaces 131 . 132 have no unwanted residues of the molding compound on the front side.

Subsequently, as in 7 from the side and in 8th shown in the top view, unhoused semiconductor chips 150 within the recesses 141 of the molding 140 on the first pads 131 arranged and over bonding wires 151 to the second pads 132 connected. As indicated above, the semiconductor chips may be 150 to radiation-emitting optoelectronic semiconductor chips 150 act. It is possible, for example, the use of LED chips.

In the arrangement indicated in the figures, the semiconductor chips 150 in each case a front side contact and a back contact. About the backside contacts and connecting layers, not shown, for example, solder layers or layers of an electrically conductive adhesive, the semiconductor chips 150 electrically and mechanically with the first connection surfaces 131 connected. The front-side contacts of the semiconductor chips 150 Be over the bonding wires 151 electrically with the second pads 132 connected.

After arranging and contacting the semiconductor chips 150 will, as in 9 is shown, a potting compound 160 in the recesses 141 of the molding 140 brought in. Every recess 141 Can be completely with the potting compound 160 be filled. The potting compound 160 surrounds the semiconductor chips 150 and the bonding wires 151 , and forms one of these components 150 . 151 Protected from external influences encapsulation.

The introduction of the potting compound 160 in the recesses 141 can be done by casting, for example. Also in this process, the carrier film 120 a back-sealing of the connection surfaces 131 . 132 cause, so that despite the presence of any gaps between the molding 140 and the connection surfaces 131 . 132 contamination of back surfaces of the pads 131 . 132 with the potting compound 160 can be avoided.

In radiation-emitting semiconductor chips 150 can be a potting compound 160 be used, which has a radiation-permeable potting material, for example, a silicone material. The potting compound 160 can be used in this context, not only for encapsulation, but also for radiation conversion. For this purpose, the potting compound 160 additionally in the radiation-permeable potting embedded phosphor particles for radiation conversion (not shown). In this way, the potting compound 160 at least a portion of an operating of the semiconductor chips 150 Convert converted light radiation (volume conversion).

It is also possible that in the case of the radiation-emitting semiconductor chips 150 Conversion layers not shown on a front side or conversion elements for radiation conversion are used (surface conversion). Such conversion layers may, for example, after the arrangement of the semiconductor chips 150 in the recesses 141 or after wire bonding and before filling the potting compound 160 on the semiconductor chips 150 to be ordered. In this embodiment, the potting compound 160 only have a radiation-permeable potting material.

Furthermore, in the case of the above-described use of a potting compound 160 With phosphor particles are eligible to let the phosphor particles settle by gravity or use of a centrifuge, so that the phosphor particles in the form of a layer on the surface of the semiconductor chip 150 can lie (not shown). As a result, a better heat dissipation can be achieved, so that operation at higher temperatures is possible.

Following this or after curing of the potting compound 160 becomes the carrier film 120 removed from the component composite, so that the in 10 shown process state is present. This can be done by peeling off the carrier film 120 take place from the component composite. In this context, can be exploited that the carrier film 120 in the previously performed and associated with a temperature effect forming process can largely lose their adhesive effect.

After removing the carrier film 120 will, as in 11 from the side and in 12 is shown in the plan, the component composite in separate electronic or optoelectronic devices 100 sporadically. For the singling is only the molding 140 which makes this process easy and quick. This approach is the design with the separate metallic pads 131 . 132 allows.

As in the 11 . 12 can be shown, the cutting along along in the plan view perpendicular to each other oriented dividing lines 190 and in areas of the molding 140 between the recesses 141 be performed. As a result, the isolated components 100 a Cuboid shape and in the plan a rectangular contour.

The severing of the molding 140 can be done for example by sawing. This is possible with a high sawing speed of, for example, up to 500mm / s. Alternatively, it is possible to cut through the shaped body 140 using other processes such as laser cutting or water jet cutting.

For the isolated components 100 are single-chip components. The components 100 each have one from the molding 140 emerged housing body 145 with a recess 141 , two separate and on a back exposed pads 131 . 132 and a semiconductor chip 150 on. The semiconductor chip 150 is in the recess 141 of the housing body 145 on a first connection surface 131 arranged over a bonding wire 151 to a second pad 132 connected, and from the into the recess 141 introduced potting compound 160 surround. The potting compound 160 forms at the components 100 each part of a front side. With the help of the rear exposed connection surfaces 131 . 132 can the components 100 be arranged by soldering or reflow soldering on a circuit board (not shown).

Every component 100 has between the front and the back of a circumferential surface 147 on, which exclusively by the housing body 145 is formed. In the embodiment shown here, the lateral surface is set 147 of the components 100 composed of four right-angled adjoining side walls. To the lateral surface 147 Approaching connecting bridges made of copper are not available. Therefore, the components 100 corrosion resistant and insensitive to short circuits.

The following are possible variants and modifications of the basis of the 1 to 12 described method described. Matching features and aspects as well as equal and equivalent components will not be described again in detail below. For details, reference is made to the above description instead. Furthermore, attention is drawn to the possibility of combining features of two or more embodiments with one another.

The 13 to 19 show on the basis of side views another possible method for producing surface mount (opto) electronic single-chip devices 100 , In this process, a metallic layer 112 only trained at a later stage of the procedure. Accordingly, the procedure of the 13 to 19 be referred to as a post-plating process, whereas the previously explained procedure of the 1 to 12 can be referred to as preplating method.

In the method, as in 13 shown is a metal foil 110 provided and on an etch-resistant carrier film 120 arranged. This can be done by laminating the carrier film 120 on the metal foil 110 respectively. The provided metal foil 110 is uncoated and therefore has only a metallic layer 111 out of, for example, Cu.

Subsequently, a wet-chemical etching process is carried out, in which the on the carrier film 120 arranged metal foil 110 , as in 14 is shown in separate flat connection elements or connection surfaces 131 . 132 is structured. The etching process may be performed by means of an etching mask such as a photoresist mask or by using mechanical masking. Seen from above, the connection surfaces 131 . 132 in the 4 have shown structure.

After forming the pads 131 . 132 will, as in 15 is shown, a contiguous shaped body 140 on the carrier foil 120 and the connecting surfaces arranged thereon 131 . 132 educated. The molded body 140 has recesses 141 on, over which the pads 131 . 132 are free on the front side. Every recess 141 is a pair of a first pad 131 and a second pad 132 assigned. Between such a pair of pads 131 . 132 is each a jetty 142 of the molding 140 available. Seen from above, the in 6 present circumstances shown. The formation of the shaped body 140 can be carried out with the aid of a molding process, for example a transfer molding process.

Following may optionally include a process for removing unwanted, on the pads 131 . 132 on the front existing residues of a molding material of the molding 140 (if available).

This is followed by the carrier film 120 from the composite comprising the pads 131 . 132 and the shaped body 140 removed, and become the pads 131 . 132 or their layer material 111 , as in 16 is shown with a metallic layer 112 coated. This approach exploits the fact that the connection surfaces 131 . 132 after forming the molding 140 over the molding 140 can be held together so that the carrier film 120 is dispensable for this. To remove the carrier film 120 subtracted from.

Coating takes place in such a way that only the connection surfaces 131 . 132 or exposed and not from the molding 140 covered surface areas of the pads 131 . 132 with the metallic layer 112 be provided, as in 16 based on the front and back of the pads 131 . 132 arranged metallic layer 112 becomes clear. The metallic layer 112 may be formed in a single-layered or multi-layered form in the form of a stack of several partial layers. Due to the metallic layer 112 can the pads 131 . 132 a solderable and for connecting bonding wires 151 have suitable surface.

Coating the connection surfaces 131 . 132 with the metallic layer 112 can be performed by means of one or more sequential metallization processes. An example of a metallization process is electroless plating.

In this process variant, the shaped body 140 exclusively on the layer material 111 (For example, Cu) of the pads 131 . 132 and not on the subsequently formed metallic layer 112 arranged. In this way, a good adhesion between the molding 140 and the connection surfaces 131 . 132 to provide. In addition, by the coating optionally present gaps between the molding 140 and the connection surfaces 131 . 132 be closed, so that the finished components 100 characterized by a high density.

Subsequently, as in 17 shown is semiconductor chips 150 within the recesses 141 of the molding 140 on the coated first pads 131 arranged and over bonding wires 151 electrically with the coated second pads 132 connected. These may be radiation-emitting chips or light-emitting diode chips. Seen from above, the in 8th present circumstances shown.

Below are the recesses 141 of the molding 140 , as in 18 is shown with a potting compound 160 filled. With regard to radiation-emitting semiconductor chips 150 can the potting compound 160 a radiation-permeable potting material and optionally embedded therein phosphor particles.

Following this is the component composite, as in 19 is shown in separate electronic or optoelectronic components 100 sporadically. For singling, which viewed from above accordingly 12 can be done, only the shaped body 140 along dividing lines 190 in areas of the molding 140 between the recesses 141 severed. This process can be done for example by sawing.

The 20 to 28 show on the basis of side views and a top view another possible process flow for the manufacture of surface mount (opto) electronic single-chip devices 100 , In this process, connecting elements 131 . 132 formed with a marginal anchoring structure.

In the method, as in 20 shown is a metal foil 110 provided. The metal foil 110 has a metallic base layer 111 from, for example, Cu on, which completely with a metallic layer 112 is coated. The metallic layer 112 which is used for providing a solderable and for connecting bonding wires 151 suitable surface, may be formed as a single-layered or multi-layered.

Below are, as in 21 is shown on one side or main side recesses 195 in the metal foil 110 educated. For this purpose, an etching process using a corresponding masking of the metal foil 110 be performed. The wells 195 can be formed with an etch depth which is more than half the thickness of the metal foil 110 , Furthermore, the depressions 195 in the form of a coherent grid in the metal foil 110 formed, whereby from the depressions 195 enclosed areas 191 . 192 the metal foil 110 be formed. This is for better illustration in addition to the supervisory presentation of 22 shown. The areas 191 . 192 the metal foil 110 are formed with molds, which subsequently formed connection elements 131 . 132 correspond. In this sense, couples are each from a larger area 191 and a smaller area 192 formed, with the areas 191 . 192 arranged in a grid of rows and columns.

After forming the half-etched pits 195 becomes the metal foil 110 , as in 23 shown with the wells 195 having side on an etch-resistant carrier film 120 arranged. This can be done by laminating the carrier film 120 on the metal foil 110 respectively.

Subsequently, a wet-chemical etching process is carried out, in which the on the carrier film 120 arranged metal foil 110 , as in 24 is shown in separate flat Connection elements or connection surfaces 131 . 132 is structured. Here, an etching mask such as a photoresist mask or a mechanical masking is used. Seen from above, the connection surfaces 131 . 132 in the 4 have shown structure.

In the etching process for forming the pads 131 . 132 becomes material of the metal foil 110 in the area of the depressions 195 starting from one side of the metal foil 110 which is opposite to the side of the metal foil 110 with the wells 195 , As a result, excess layer material in the region of the previously generated depressions 195 removed, leaving the separate pads 131 . 132 on the carrier foil 120 be formed. The etching to form the pads 131 . 132 is performed in Ätzbereichen, which have a smaller width than the previously formed wells 195 , As a result, the pads 131 . 132 , as in 24 is shown at the edge have a circumferential step shape, which can serve as anchoring structure.

After forming the pads 131 . 132 will, as in 25 is shown, a contiguous shaped body 140 on the carrier foil 120 and the pads thereon 131 . 132 educated. The molded body 140 has recesses 141 on, over which the pads 131 . 132 exposed on the front. Every recess 141 is a pair of a first pad 131 and a second pad 132 assigned. Seen from above, the in 6 present circumstances shown. The formation of the shaped body 140 can be carried out with the aid of a molding process, for example a transfer molding process.

Due to the stepped edges of the connection surfaces 131 . 132 can be an anchoring between the molding 140 and the connection surfaces 131 . 132 , and thereby an improved mechanical connection between these components 131 . 132 . 140 be enabled. The stepped shape of the connection surfaces 131 . 132 on the edge also leads to the side next to or between the pads 131 . 132 contained components of the molding 140 like back sections of a recesses 141 surrounding and side walls of the recesses 141 forming part of the molding 140 and footbridges 142 have a different form from the previously described procedures.

After forming the shaped body 140 Optionally, a process for removing unwanted, on the pads 131 . 132 on the front existing residues of a molding material of the molding 140 (if available).

Subsequently, as in 26 shown is semiconductor chips 150 within the recesses 141 of the molding 140 on the first pads 131 arranged and over bonding wires 151 electrically to the second pads 132 connected. In this case, radiation-emitting chips or light-emitting diode chips can be used. Seen from above, the in 8th present circumstances shown.

Following this are the recesses 141 of the molding 140 , as in 27 is shown with a potting compound 160 filled. The potting compound 160 may comprise a radiation-permeable potting material and optionally contained therein phosphor particles.

Subsequently, the component composite, as in 28 is shown in separate (opto) electronic components 100 sporadically. For singling, which viewed from above accordingly 12 can be done, only the shaped body 140 along dividing lines 190 in areas of the molding 140 between the recesses 141 severed. The separation can be done by means of sawing.

The previously described method of 20 to 28 can be modified in the same way that a metallic layer 112 is formed only at a later stage of the procedure. Such a procedure known as the post-plating method, in which connection elements 131 . 132 be generated with a marginal anchoring structure is described below with reference to the 29 to 36 described. In this sense, the previous procedure of the 20 to 28 be referred to as preplating method.

In the method, as in 29 shown is a metal foil 110 provided. The provided metal foil 110 is uncoated and therefore has only a metallic layer 111 out of, for example, Cu.

Below are, as in 30 is shown, on one side depressions 195 in the metal foil 110 educated. This can be done by means of an etching process using an appropriate masking of the metal foil 110 be performed. The wells 195 can have an etch depth more than half the thickness of the metal foil 110 be generated. Further, the pits become 195 in the form of a grid in the metal foil 110 formed, whereby from the depressions 195 enclosed areas 191 . 192 the metal foil 110 educated become. The areas 191 . 192 have shapes according to subsequently formed connection elements 131 . 132 , There are pairs from a larger area 191 and a smaller area 192 formed, which are arranged in a grid of rows and columns. Seen from above, the depressions can 195 and the areas 191 . 192 in the 22 have shown structure.

Following the formation of the half-etched pits 195 becomes the metal foil 110 with the wells 195 having side on an etch-resistant carrier film 120 arranged and subjected to a structuring, so that, as in 31 is shown, separate flat connection elements or connection surfaces 131 . 132 be formed. The placing can be done by laminating the carrier foil 120 on the metal foil 110 respectively. The structuring of the metal foil 110 is performed by means of a wet chemical etching process using an etching mask, for example a photoresist mask, or a mechanical masking. Seen from above, the connection surfaces 131 . 132 in the 4 have shown structure.

In the etching process, material becomes the metal foil 110 in the area of the depressions 195 starting from one side of the metal foil 110 which is opposite to the side of the metal foil 110 with the wells 195 , Also, in this process, etching is performed with one opposite the pits 195 lower etching width, reducing the contact surfaces 131 . 132 have on the edge of a circumferential and serving as an anchoring structure step shape.

Following this, as in 32 is shown, a contiguous shaped body 140 on the carrier foil 120 and the pads arranged thereon 131 . 132 educated. In this case, the stepped edges of the connection surfaces 131 . 132 an anchoring and thereby an improved mechanical connection between the molding 140 and the connection surfaces 131 . 132 , The molded body 140 has recesses 141 on, over which the pads 131 . 132 are free on the front side. Every recess 141 is a pair of a first pad 131 and a second pad 132 assigned. Between such a pair of pads 131 . 132 there is a footbridge 142 of the molding 140 , Seen from above, the in 6 present circumstances shown. The formation of the shaped body 140 can be carried out with the aid of a molding process, for example a transfer molding process.

After forming the shaped body 140 Optionally, a process for removing unwanted, on the pads 131 . 132 on the front existing residues of a molding material of the molding 140 (if available).

The following is the carrier film 120 from the composite comprising the pads 131 . 132 and the shaped body 140 removed or subtracted, and become the pads 131 . 132 or their layer material 111 , as in 33 is shown with a metallic layer 112 coated. The coating takes place in such a way that the metallic layer 112 only on the pads 131 . 132 or on exposed and not on the molding 140 covered surface areas of the pads 131 . 132 is trained.

The metallic layer 112 , which can be produced in a single-layered or multi-layered, gives the connection surfaces 131 . 132 a solderable and for connecting bonding wires 151 suitable surface. The coating is carried out by means of one or more sequential metallization processes.

Subsequently, as in 34 shown is semiconductor chips 150 within the recesses 141 of the molding 140 on the coated first pads 131 arranged and over bonding wires 151 to the coated second pads 132 connected. In this case, radiation-emitting chips or light-emitting diode chips can be used. Seen from above, the in 8th present circumstances shown.

Below are the recesses 141 of the molding 140 , as in 35 is shown with a potting compound 160 filled. The potting compound 160 may comprise a radiation-permeable potting material and optionally contained therein phosphor particles.

Following this is the component composite, as in 36 is shown in separate (opto) electronic components 100 sporadically. The singling, which viewed from above accordingly 12 can be carried out, is carried out such that only the shaped body 140 along dividing lines 190 in areas of the molding 140 between the recesses 141 is severed. This can be done by sawing.

The embodiments explained with reference to the figures represent preferred or exemplary embodiments of the invention. In addition to the described and illustrated embodiments, further embodiments are conceivable which may comprise further modifications and / or combinations of features. For example, it is possible to use other materials instead of the above materials.

Also, components and structures, for example, connection elements 131 . 132 as well as recesses 141 a shaped body 140 to be realized with other shapes and geometries. For example, instead of rectangular recesses 141 in the supervision round or oval recesses are formed.

It may also be considered, a carrier sheet used 120 on another solid support to provide greater stability. This can be after or even before arranging a metal foil to be structured 110 on the carrier foil 120 and before forming a shaped article 140 respectively. The solid support can be, for example, a metal-based support, a glass carrier or also a plastic-based carrier. The arrangement of the carrier film 120 on the solid support can be done for example by gluing. This can be a double-sided adhesive film between the carrier film 120 and the solid support. After forming the shaped body 140 or after filling a potting compound 160 can the carrier film 120 and the solid support is removed. The detachment of these constituents can be favored if the adhesive film used is a so-called thermorelease film, which can lose its adhesive effect under the action of temperature. In this connection, a thermorelease film may be used in which a thermorelease process (foaming) occurs at a temperature greater than a temperature present in the molding process. It can thereby be achieved that the thermorelease film does not already have its adhesive effect during the formation of the shaped body 140 loses.

Other possible modifications are with respect to the usable semiconductor chips 150 possible. It can, for example, semiconductor chips 150 come used, which have two backside contacts. In such an embodiment, for the semiconductor chips 150 two connection elements each 131 . 132 be provided. In this case, each semiconductor chip 150 with the two backside contacts on two connectors 131 . 132 be arranged and connected with these.

Furthermore, semiconductor chips 150 to be used with two front side contacts. In such an embodiment, two connection elements can likewise each be used 131 . 132 for the semiconductor chips 150 be provided. In this case, each semiconductor chip 150 on a connection element 131 arranged, and may be one of the two front-side contacts via a bonding wire 151 to the same connection element 131 be connected. The other front contact can be via another bonding wire 151 with another connection element 132 get connected.

For semiconductor chips 150 with two front contacts can also be provided in each case three connection elements. In this way, each semiconductor chip 150 can be arranged on a connection element, and can the front side contacts via bonding wires 151 be connected with two other connection elements.

The method or its different embodiments can not only be used in relation to the production of optoelectronic components, but can also be used for the manufacture of other electronic components. Therefore, other semiconductor chips can be used instead of optoelectronic semiconductor chips.

Another possible modification is to manufacture multichip components instead of single-chip components, which comprise a plurality of semiconductor chips 150 exhibit. For example, such components may each comprise one of a shaped body 140 emerged housing body with several separate recesses 141 in which semiconductor chips 150 can be arranged on corresponding connection elements.

For this purpose, for example, in the 10 . 18 . 27 . 35 Pictured component composite by an appropriate choice of the dividing lines 190 in multi-chip components with multiple recesses 141 , and not in the components shown 100 to be isolated. In such multi-chip devices can in the recesses 141 arranged semiconductor chips 150 operated separately.

It is furthermore possible to produce multi-chip components, each of which has a housing body with a common recess, and a plurality of semiconductor chips arranged within the common recess 150 exhibit. Several semiconductor chips 150 can be arranged on a single, or even on one or more common connection elements. The method can be carried out for this purpose in such a way that in the region of a recess of the shaped body 140 in each case a plurality of connecting elements is present. Also, several can in a common recess of the molding 140 arranged semiconductor chips 150 electrically connected to each other, for example by means of bonding wires 151 ,

While the invention has been further illustrated and described in detail by way of 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.

LIST OF REFERENCE NUMBERS

100

 module

110

 metal foil

111

 Layer, layer material

112

 layer

115

 deepening

120

 support film

131, 132

 terminal area

140

 moldings

141

 recess

142

 web

145

 housing body

147

 lateral surface

150

 Semiconductor chip

151

 bonding wire

160

 potting compound

190

 parting line

191, 192

 Area

195

 deepening

Claims (9)

Method for producing electronic components ( 100 ), comprising: providing a metal foil ( 110 ); Arranging the metal foil ( 110 ) on a subcarrier ( 120 ); Structuring the on the subcarrier ( 120 ) arranged metal foil ( 110 ) in separate connection elements ( 131 . 132 ); Forming a shaped body ( 140 ) with recesses ( 141 ) on the subcarrier ( 120 ) and the connection elements ( 131 . 132 ); Arranging semiconductor chips ( 150 ) on connection elements ( 131 ) in the recesses ( 141 ) of the shaped body ( 140 ); Removing the subcarrier ( 120 ); and severing the shaped body ( 140 ) for forming isolated electronic components ( 100 ). The method of claim 1, wherein the provided metal foil ( 110 ) a metallic base layer ( 111 ), which with a metallic layer ( 112 ) is coated. Method according to one of the preceding claims, wherein the connecting elements ( 131 . 132 ) after forming the shaped body ( 140 ) and before arranging semiconductor chips ( 150 ) with a metallic layer ( 112 ) are coated. Method according to one of the preceding claims, wherein the subcarrier ( 120 ) is a carrier film. Method according to one of the preceding claims, wherein the structuring of the metal foil ( 110 ) in the separate connection elements ( 131 . 132 ) is performed by means of an etching process. Method according to one of the preceding claims, further comprising introducing a potting compound ( 160 ) into the recesses ( 141 ) of the shaped body ( 140 ). Method according to one of the preceding claims, further comprising forming depressions ( 195 ) in the metal foil ( 110 ) before placing the metal foil ( 110 ) on the subcarrier ( 120 ), the depressions ( 195 ) on a first side of the metal foil ( 110 ), and wherein in structuring the metal foil ( 110 ) in the separate connection elements ( 131 . 132 ) Material of the metal foil ( 110 ) starting from a second side of the metal foil opposite the first side ( 110 ) in the area of the depressions ( 195 ) is removed, so that the connection elements ( 131 . 132 ) at the edge of an anchoring structure for anchoring the shaped body ( 140 ) exhibit. Method according to one of the preceding claims, wherein the electronic components ( 100 ) are optoelectronic components, and wherein optoelectronic semiconductor chips ( 150 ) on connection elements ( 131 ) in the recesses ( 141 ) of the shaped body ( 140 ) to be ordered. Electronic component ( 100 ) produced by carrying out a method according to one of the preceding claims, wherein the electronic component ( 100 ) one by the severing from the shaped body ( 140 ) emerged housing body ( 145 ), and wherein the electronic component ( 100 ) a circumferential lateral surface ( 147 ), which exclusively through the housing body ( 145 ) is formed.

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