DE102013022642B3 - Optoelectronic semiconductor component - Google Patents

Abstract

Optoelectronic semiconductor component (1) with a mounting surface (15) and a radiation exit surface (10) opposite the mounting surface, wherein- the semiconductor component has a semiconductor chip (2) provided for generating radiation;- the semiconductor component has a housing body (3) which surrounds the semiconductor chip in a lateral direction;- the semiconductor chip is free of material of the housing body on the radiation exit area; and- a fillet (4) which is formed between the housing body (3) and the semiconductor chip (2) adjoins a side surface (20) of the semiconductor chip;- the semiconductor chip has a semiconductor body with an active region (22) provided for generating radiation and a substrate (25) on which the semiconductor body is arranged, the substrate (25) being a growth substrate for the semiconductor layers of the semiconductor body;- the optoelectronic semiconductor component on the mounting area (15) has a first contact (61) and a second contact (62), wherein at least one of the contacts (61, 62) is electrically conductively connected to the semiconductor chip (2) via a via (63); and - the via (63) does not pass through the groove (4).

Description

For semiconductor components such as light-emitting diodes, designs are known, for example, in which the semiconductor chips provided for generating radiation are mounted in prefabricated housings. Such designs are difficult to miniaturize to produce particularly compact LEDs.

The publication WO 2011/161 183 A1 describes an optoelectronic semiconductor component.

Document US 2011/0 049 545 A1 relates to an LED package with a phosphor panel and a reflective substrate.

A coated light-emitting component is specified in publication US 2011/0 175 117 A1.

The publication US 2012/0 056 228 A1 describes a method for encapsulating LED chips.

The pamphlet DE 10 2009 036 621 A1 describes a method for producing an optoelectronic semiconductor component.

One object is to specify an optoelectronic semiconductor component that has a compact design and high decoupling efficiency and can be reliably manufactured.

This object is achieved by a semiconductor component according to independent patent claim 1 . Configurations and expediencies are the subject matter of the dependent patent claims.

A method for producing a plurality of optoelectronic semiconductor components is specified.

In accordance with at least one embodiment of the method, the method has a step in which a plurality of semiconductor chips is provided. The in particular optoelectronic semiconductor chips are spaced apart from one another in a lateral direction. For example, the semiconductor chips are present on an auxiliary carrier. The auxiliary carrier can be flexible, for example as a film, or rigid.

In accordance with at least one embodiment of the method, the method comprises a step in which a package body assembly is formed, which is arranged at least in regions between the semiconductor chips. The housing body composite is produced in particular by means of a casting process. The term casting process includes all production processes in which a molding composition is introduced into a predetermined mold and, in particular, is subsequently cured. In particular, the term casting process includes casting, injection molding, transfer molding and compression molding.

The housing body assembly and thus the housing body formed from the housing body assembly is designed to be radiation-impermeable in particular for the radiation to be detected or emitted by the semiconductor chip during operation of the semiconductor component.

In one configuration variant, the housing body is designed to be reflective for the radiation, that is to say the housing body has a reflectivity of at least 55%. The reflectivity is preferably at least 80%.

In an alternative configuration variant, the housing body is designed to absorb the radiation. This means that the housing body absorbs at least 55% of the incident radiation. For example, the case body is formed by a black material.

The semiconductor chips have, in particular, a semiconductor body with an active region provided for generating radiation. The semiconductor body, in particular the active region, contains a III-V compound semiconductor material, for example. Furthermore, the semiconductor chip comprises in particular a carrier on which the semiconductor body is arranged. For example, the carrier is a growth substrate for the semiconductor layers of the semiconductor body. Alternatively, the carrier is different from a growth substrate for the semiconductor layers of the semiconductor body. In this case, the carrier serves to mechanically stabilize the semiconductor body, so that the growth substrate is not required for this and can be removed.

A semiconductor chip in which the growth substrate has been removed is also referred to as a thin-film semiconductor chip.

According to at least one embodiment of the method, the method comprises a step in which a plurality of fillets are formed, each of which is adjacent to a semiconductor chip. In the lateral direction, the fillets are each delimited by a side surface of the respective semiconductor chip and the package body assembly. In the region of the fillets, the package body assembly therefore does not directly adjoin the side surface of the semiconductor chips.

In the vertical direction, the fillets can extend over the entire height of the semiconductor chip or only over part of the semiconductor chip. In case of doubt, a vertical direction is understood to mean a direction that runs perpendicularly to the mounting surface of the semiconductor component. Accordingly, a lateral direction runs parallel to the mounting surface.

The fillets are provided in particular to increase the decoupling efficiency of the semiconductor chips.

In accordance with at least one embodiment of the method, the method comprises a step in which the package body assembly is singulated into a plurality of optoelectronic semiconductor components, each singulated semiconductor component having at least one semiconductor chip and part of the package body assembly as the package body.

The housing bodies are therefore only produced from the housing body assembly when it is separated and thus at a point in time at which the semiconductor chips are already located in the housing body.

In accordance with at least one embodiment of the method, the semiconductor chips are each free of the material of the housing body on a radiation exit area of the semiconductor components opposite a mounting area when the housing body assembly is singulated. Furthermore, the semiconductor chips can be free of the material of the housing body on the mounting surface. On the radiation exit surface and possibly also on the mounting surface there is no material of the housing body, apart from any residues that may be caused by production. The semiconductor chips which are arranged in the housing body and are mechanically stably connected to the housing body are therefore embedded in the housing body only in the lateral direction. The semiconductor chips can extend completely through the housing body in the vertical direction.

In at least one embodiment of the method for producing a plurality of optoelectronic semiconductor components, a plurality of semiconductor chips is provided, which are spaced apart from one another in a lateral direction. A package body assembly is formed, which is arranged at least in regions between the semiconductor chips. A plurality of fillets are formed, each adjacent to a semiconductor chip and bounded in a lateral direction by a side surface of the respective semiconductor chip and the package body assembly. The package body assembly is singulated into a plurality of optoelectronic semiconductor components, each semiconductor component having at least one semiconductor chip and a part of the package body assembly as the package body, and wherein the semiconductor chips are free of the material of the package body on a radiation exit surface of the semiconductor components opposite a mounting surface.

In the case of a semiconductor component embodied as a radiation emitter, the decoupling efficiency from the semiconductor chip can be increased by means of the fillet. A maximum lateral extent of the groove is preferably at most 100 μm, particularly preferably at most 50 μm. A compact configuration of the semiconductor component is thus simplified.

According to at least one embodiment of the method, the semiconductor chips are each free of material of the housing body on the mounting surface. The semiconductor chips are therefore accessible on the mounting surface, for example for thermal contacting and/or electrical contacting.

According to at least one embodiment of the method, the throat is radiolucent. In particular, the fillet is transparent or at least translucent for the radiation generated or to be detected by the semiconductor component during operation. The generated radiation can be coupled into the fillet on a side surface of the semiconductor chip and exit from the fillet on the side of the radiation exit surface.

According to at least one embodiment of the method, the fillet has a reflectivity of at least 80%. In particular, the fillet has a higher reflectivity than the material of the housing body. In this case, the absorption losses can be reduced by means of the throat.

In accordance with at least one embodiment of the method, the semiconductor chips for forming the fillets are deformed with a deforming material before the package body assembly is formed in such a way that the side surfaces of the semiconductor chips are at least partially covered and the molding material is deformed by a molding compound for the package body assembly when the package body assembly is formed. The formation of the fillets, in particular the definition of the geometric shape of the fillets, is therefore carried out at least partially before the housing body assembly is formed. At the points at which the encapsulation material is present, the molding compound for the package body assembly does not directly adjoin the side surface of the semiconductor chips to be encapsulated.

In accordance with at least one embodiment of the method, the semiconductor chips are arranged on an auxiliary carrier when the package body assembly is formed and/or when the plurality of fillets are formed. The auxiliary carrier can be removed before the housing body assembly is separated.

A film, such as a self-adhesive film or a rigid carrier, for example, is suitable as the auxiliary carrier.

In accordance with at least one embodiment of the method, the encapsulation material is applied in such a way that it at least partially covers the side faces of the semiconductor chips and the auxiliary carrier in each case. When the encapsulation material is applied, the semiconductor chips are therefore already arranged on the auxiliary carrier. The encapsulation material is in particular applied to the semiconductor chips in such a way that the main surface of the semiconductor chip facing away from the auxiliary carrier remains free of the encapsulation material. The forming material can, for example, be printed on or applied by means of a dispenser.

In accordance with at least one embodiment of the method, the encapsulation material is applied to an auxiliary carrier and the semiconductor chips are pressed into the encapsulation material in such a way that the encapsulation material covers the side faces of the semiconductor chips at least in regions. In this case, the encapsulation material can simultaneously serve to attach the semiconductor chips to the auxiliary carrier. In this case, the thickness of the encapsulation material is specifically set in such a way that the side faces of the semiconductor chips are wetted completely or at least in regions with the encapsulation material. The main surface of the semiconductor chips facing away from the auxiliary carrier remains free of the encapsulation material.

In accordance with at least one embodiment of the method, the encapsulation material is a filling material that remains in the semiconductor components. For example, the filling material is a radiation-transmissive material. The filling material can furthermore contain a radiation conversion material which is provided for the at least partial radiation conversion of radiation generated in the semiconductor chips.

Alternatively, the filling material can have a reflectivity of at least 80% for the radiation to be generated and/or received by the semiconductor chip. Radiation absorption on the housing body, in particular also in the case of a housing body designed to be absorbent, can be avoided or at least reduced by means of a reflective fillet.

According to at least one embodiment of the method, the forming material is an auxiliary material that is removed after the housing body assembly has been formed. The auxiliary material is therefore only used to form the plurality of fillets when the housing body assembly is formed. In other words, the geometric shape of the later fillets is determined by the auxiliary material. The auxiliary material thus prevents the molding compound from completely covering the side faces of the semiconductor chips to be shaped when the package body assembly is formed. For example, a suitable auxiliary material is an adhesive that can be removed comparatively easily, for example by the action of temperature, a solvent and/or a wet-chemical etching process.

In accordance with at least one embodiment of the method, the plurality of fillets are formed after the housing body assembly has been formed. The molding compound of the package body assembly can therefore cover the side faces of the semiconductor chips over their entire surface before the fillets are formed. For example, material of the composite housing body is removed to form the grooves. This is done, for example, by means of coherent radiation, such as laser radiation. The fillets are preferably formed in such a way that the molding compound of the package body assembly adjoins the side faces with a surface occupancy of at most 50% of the side faces of the semiconductor chips.

According to at least one embodiment of the method, the fillet is filled with a filling material after the housing body assembly has been formed. In comparison to an unfilled fillet, the difference in refractive index on the side surface of the semiconductor chip can be reduced by means of the filling material.

In accordance with at least one embodiment of the method, the semiconductor chips are overmolded when the package body assembly is formed, and the package body assembly is subsequently thinned, so that the semiconductor chips are exposed in regions. The main area of the semiconductor chips facing away from the auxiliary carrier is therefore initially covered by the material of the housing body assembly and is subsequently uncovered again. The housing body composite can be thinned mechanically, for example, by means of grinding or lapping.

By exposing the semiconductor chips, semiconductor components can be produced in which the heat loss generated in the semiconductor chips during operation can be dissipated directly at the mounting surface of the semiconductor components without that the heat must pass through the material of the case body.

In accordance with at least one embodiment, an optoelectronic semiconductor component has a mounting area and a radiation exit area opposite the mounting area. Furthermore, the semiconductor component has a semiconductor chip provided for generating and/or receiving radiation.

In accordance with at least one embodiment of the optoelectronic semiconductor component, the semiconductor component has a housing body which surrounds the semiconductor chip in a lateral direction, the semiconductor chip being free of the material of the housing body at the radiation exit area. For example, the housing body does not project in the vertical direction on the side opposite the mounting surface, or at least not significantly, for example by at most 10 μm, beyond the semiconductor chip.

In accordance with at least one embodiment of the optoelectronic semiconductor component, a fillet adjoins a side surface of the semiconductor chip, which fillet is delimited in a lateral direction running parallel to the mounting surface by the side surface of the semiconductor chip under the housing body.

In at least one embodiment of the optoelectronic semiconductor component, the semiconductor component has a mounting area and a radiation exit area opposite the mounting area. The semiconductor component has a semiconductor chip provided for generating and/or receiving radiation. The semiconductor device has a package body surrounding the semiconductor chip in a lateral direction. The semiconductor chip is free of the material of the housing body at the radiation exit area. A fillet adjoins a side face of the semiconductor chip, which fillet is delimited by the side face of the semiconductor chip and the package body in a lateral direction running parallel to the mounting face.

The housing body can directly adjoin the semiconductor chip in some areas in the lateral direction or be spaced apart from the semiconductor chip at any point along the entire circumference of the semiconductor chip. The housing body is preferably at a distance of at most 10 μm from the semiconductor chip at at least one point. A particularly compact semiconductor component can be realized in this way.

In accordance with at least one embodiment of the semiconductor component, the fillet runs along the entire circumference of the semiconductor chip. The semiconductor body is therefore not directly adjacent to the semiconductor chip at least in regions along the entire circumference in the vertical direction.

In accordance with at least one embodiment of the semiconductor component, the fillet tapers in the direction of the mounting area, as viewed from the radiation exit area. For example, seen from the radiation exit surface, the throat has a convex curvature.

Radiation emerging from the side surface of the semiconductor chip can thus be efficiently deflected to the normal onto the radiation exit surface.

In accordance with at least one embodiment of the semiconductor component, the fillet contains a radiation conversion material. The radiation conversion material is provided, for example, to convert primary radiation generated in the semiconductor chip with a first peak wavelength into secondary radiation with a second peak wavelength that differs from the first peak wavelength. For example, the semiconductor component is provided for generating a mixed light, in particular a mixed light that appears white to the human eye.

The method described above for producing optoelectronic semiconductor components is particularly suitable for producing the optoelectronic semiconductor component. Features cited in connection with the method can therefore also be used for the semiconductor component or vice versa.

1. 1. Verfahren zum Herstellen einer Mehrzahl von optoelektronischen Halbleiterbauelementen mit den Schritten:
   1. a) Bereitstellen einer Mehrzahl von Halbleiterchips, die in einer lateralen Richtung voneinander beabstandet sind;
   2. b) Ausbilden eines Gehäusekörperverbunds, der zumindest bereichsweise zwischen den Halbleiterchips angeordnet ist;
   3. c) Ausbilden einer Mehrzahl von Kehlen, die jeweils an einen Halbleiterchip angrenzen und die in lateraler Richtung durch eine Seitenfläche des jeweiligen Halbleiterchips und den Gehäusekörperverbund begrenzt sind; und
   4. d) Vereinzeln des Gehäusekörperverbunds in eine Mehrzahl von optoelektronischen Halbleiterbauelementen, wobei jedes Halbleiterbauelement zumindest einen Halbleiterchip und einen Teil des Gehäusekörperverbunds als Gehäusekörper aufweist und wobei die Halbleiterchips jeweils an einer einer Montagefläche gegenüberliegenden Strahlungsaustrittsfläche der Halbleiterbauelemente frei von Material des Gehäusekörpers sind.
2. 2. Verfahren nach Aspekt 1, bei dem die Kehle strahlungsdurchlässig ist oder eine Reflektivität von mindestens 80 % aufweist.
3. 3. Verfahren nach Aspekt 1 oder 2, wobei die Halbleiterchips jeweils an der Montagefläche der Halbleiterbauelemente frei von Material des Gehäusekörpers sind.
4. 4. Verfahren nach einem der Aspekte 1 bis 3, bei dem die Halbleiterchips zur Ausbildung der Kehlen vor Schritt b) mit einem Umformungsmaterial derart umformt werden, dass die Seitenflächen der Halbleiterchips zumindest teilweise bedeckt sind und das Umformungsmaterial in Schritt b) von einer Formmasse für den Gehäusekörperverbund umformt wird.
5. 5. Verfahren nach Aspekt 4, bei dem die Halbleiterchips beim Aufbringen des Umformungsmaterials auf einem Hilfsträger angeordnet sind und das Umformungsmaterial so aufgebracht wird, dass es die Seitenflächen der Halbleiterchips und den Hilfsträger jeweils zumindest teilweise bedeckt.
6. 6. Verfahren nach Aspekt 4, bei dem das Umformungsmaterial auf einen Hilfsträger aufgebracht wird und die Halbleiterchips so in das Umformungsmaterial gedrückt werden, dass das Umformungsmaterial zumindest bereichsweise die Seitenflächen der Halbleiterchips bedeckt.
7. 7. Verfahren nach einem der Aspekte 4 bis 6, bei dem das Umformungsmaterial ein Füllmaterial ist, das in den Halbleiterbauelementen verbleibt.
8. 8. Verfahren nach einem der Aspekte 4 bis 6, bei dem das Umformungsmaterial ein Hilfsmaterial ist, das nach Schritt b) entfernt wird.
9. 9. Verfahren nach einem der Aspekte 1 bis 3, bei dem Schritt c) nach Schritt b) durchgeführt wird, wobei Material des Gehäusekörperverbunds zur Ausbildung der Kehlen entfernt wird.
10. 10. Verfahren nach Aspekt 8 oder 9, bei dem die Kehle nach Schritt b) mit einem Füllmaterial befüllt wird.
11. 11. Verfahren nach einem der vorhergehenden Aspekte, bei dem die Halbleiterchips in Schritt b) überformt werden und der Gehäusekörperverbund nachfolgend gedünnt wird, so dass die Halbleiterchips bereichsweise freiliegen.
12. 12. Optoelektronisches Halbleiterbauelement mit einer Montagefläche und einer der Montagefläche gegenüber liegenden Strahlungsaustrittsfläche, wobei
    • - das Halbleiterbauelement einen zur Erzeugung und/oder zum Empfangen von Strahlung vorgesehenen Halbleiterchip aufweist;
    • - das Halbleiterbauelement einen Gehäusekörper aufweist, der den Halbleiterchip in einer lateralen Richtung umgibt;
    • - der Halbleiterchip an der Strahlungsaustrittsfläche frei von Material des Gehäusekörpers ist; und
    • - an eine Seitenfläche des Halbleiterchips eine Kehle angrenzt, die in einer parallel zur Montagefläche verlaufenden lateralen Richtung durch die Seitenfläche des Halbleiterchips und den Gehäusekörper begrenzt ist.
13. 13. Halbleiterbauelement nach Aspekt 12, wobei die Kehle entlang des gesamten Umfangs des Halbleiterchips verläuft und sich von der Strahlungsaustrittsfläche aus gesehen in Richtung der Montagefläche verjüngt.
14. 14. Halbleiterbauelement nach Aspekt 12 oder 13, wobei die Kehle ein Strahlungskonversionsmaterial enthält.
15. 15. Halbleiterbauelement nach einem der Aspekte 12 bis 14, das nach einem der Aspekte 1 bis 11 hergestellt ist.

The method or the optoelectronic semiconductor component can be characterized in particular by at least one of the following aspects, which are numbered and provided with back references for the sake of simplified illustration.

1. 1. A method for producing a plurality of optoelectronic semiconductor components with the steps:
   1. a) providing a plurality of semiconductor chips spaced from each other in a lateral direction;
   2. b) formation of a housing body assembly which is arranged at least in regions between the semiconductor chips;
   3. c) forming a plurality of fillets, each adjacent to a semiconductor chip and bounded in a lateral direction by a side surface of the respective semiconductor chip and the package body assembly; and
   4. d) Separation of the package body assembly into a plurality of optoelectronic semiconductor components, each semiconductor component having at least one semiconductor chip and a part of the package body assembly as the package body, and wherein the semiconductor chips are each free of material of the package body on a radiation exit surface of the semiconductor components opposite a mounting surface.
2. 2. The method of aspect 1, wherein the throat is radiolucent or has a reflectivity of at least 80%.
3. 3. The method according to aspect 1 or 2, wherein the semiconductor chips are each free of material of the package body on the mounting surface of the semiconductor components.
4. 4. The method according to any one of aspects 1 to 3, in which the semiconductor chips to form the fillets are reshaped before step b) with a reshaping material such that the side surfaces of the semiconductor chips are at least partially covered and the reshaping material in step b) of a molding compound for the housing body composite is formed.
5. 5. The method according to aspect 4, in which the semiconductor chips are arranged on an auxiliary carrier when the encapsulation material is applied and the encapsulation material is applied in such a way that it at least partially covers the side surfaces of the semiconductor chips and the auxiliary carrier.
6. 6. The method according to aspect 4, in which the encapsulation material is applied to an auxiliary carrier and the semiconductor chips are pressed into the encapsulation material in such a way that the encapsulation material covers the side faces of the semiconductor chips at least in regions.
7. 7. The method of any one of aspects 4 to 6, wherein the reforming material is a fill material that remains in the semiconductor devices.
8. 8. The method according to any one of aspects 4 to 6, in which the reforming material is an auxiliary material which is removed after step b).
9. 9. The method according to any one of aspects 1 to 3, in which step c) is performed after step b), wherein material of the housing body composite is removed to form the fillets.
10. 10. Method according to aspect 8 or 9, in which the fillet is filled with a filling material according to step b).
11. 11. Method according to one of the preceding aspects, in which the semiconductor chips are overmolded in step b) and the package body assembly is subsequently thinned, so that the semiconductor chips are exposed in regions.
12. 12. An optoelectronic semiconductor component having a mounting surface and a radiation exit surface lying opposite the mounting surface, wherein
    • - the semiconductor component has a semiconductor chip provided for generating and/or receiving radiation;
    • - The semiconductor component has a housing body which surrounds the semiconductor chip in a lateral direction;
    • - the semiconductor chip is free of material of the housing body on the radiation exit area; and
    • - A fillet adjoins a side surface of the semiconductor chip, which is delimited in a lateral direction running parallel to the mounting surface by the side surface of the semiconductor chip and the housing body.
13. 13. The semiconductor component according to aspect 12, wherein the fillet runs along the entire circumference of the semiconductor chip and, seen from the radiation exit area, tapers in the direction of the mounting area.
14. 14. The semiconductor device of aspect 12 or 13, wherein the fillet includes a radiation conversion material.
15. 15. A semiconductor device according to any one of aspects 12 to 14, made according to any one of aspects 1 to 11.

Further features, refinements and expediencies result from the following description of the exemplary embodiments in conjunction with the figures.

Identical, similar or equivalent elements are provided with the same reference symbols in the figures.

The figures and the relative sizes of the elements shown in the figures are not to be regarded as being to scale. Rather, individual elements and in particular layer thicknesses can be exaggerated for better representation and/or for better understanding.

• die 1A bis 1E, 2A bis 2E und 3A bis 3E jeweils ein Ausführungsbeispiel für ein Verfahren zur Herstellung von optoelektronischen Halbleiterbauelementen anhand von jeweils in schematischer Schnittansicht dargestellten Zwischenschritten; und
• die 4A und 4B ein Ausführungsbeispiel für ein Halbleiterbauelement in Draufsicht (4B) und zugehöriger Schnittansicht (4A).

Show it:

• the 1A until 1E , 2A until 2E and 3A until 3E one exemplary embodiment of a method for producing optoelectronic semiconductor components based on intermediate steps each shown in a schematic sectional view; and
• the 4A and 4B an embodiment of a semiconductor component in plan view ( 4B ) and associated section view ( 4A ).

In the 1A until 1E a first exemplary embodiment of a method for producing a plurality of optoelectronic semiconductor components is shown. As in 1A A plurality of semiconductor chips 2 is shown arranged on an auxiliary carrier 5 . The following description is given by way of example for radiation-emitting semiconductor components. The semiconductor chips are, for example, luminescence diode semiconductor chips, such as light-emitting diode semiconductor chips. Deviating from this, however, the semiconductor components can also be provided for receiving radiation and can have, for example, a semiconductor chip designed as a photodiode.

The semiconductor chips 2 extend in a vertical direction between a front side 28 and a rear side 29. The front side refers to that side of the semiconductor chips through which the radiation generated in the semiconductor chips exits during operation of the subsequent semiconductor components. The semiconductor chips are arranged on the auxiliary carrier 5 in such a way that the front faces the auxiliary carrier.

A self-adhesive film, for example, is suitable for the auxiliary carrier 5 . Alternatively, the semiconductor chips can also be attached by means of a temporary adhesive, by means of a wax, by means of so-called expancels or by means of a silicone. The means causing the adhesion of the semiconductor chips can be formed exclusively below the semiconductor chips, so that the auxiliary carrier is exposed between the semiconductor chips. Alternatively, the auxiliary carrier can be covered over its entire surface.

A filling material 40 is applied to the auxiliary carrier 5 in such a way that the filling material completely or at least partially covers the side faces 20 of the semiconductor chips. This can be done, for example, by means of a dispenser. Optionally, the auxiliary carrier 5 can be structured in the lateral direction in such a way that it has wetting surfaces 51 . The wetting areas have a higher wettability than the areas of the surface of the auxiliary carrier 5 that are arranged between the wetting areas 51 and face the semiconductor chips 2. For example, the wetting areas 51 can be hydrophilic and the other areas of the surface of the auxiliary carrier 5 can be hydrophobic.

For example, silicone can be characterized by hydrophobic properties.

The geometric shape of the fillets is therefore not determined by a predefined mold, but is self-organized. In particular, the geometric shape can be adjusted by the material properties of the filling material 40, for example the surface tension and the viscosity, and the wettability of the auxiliary carrier and the semiconductor chip 2 with the filling material.

The lateral extent of the fillet 4 decreases from the front side of the semiconductor chip 28 in the direction of the rear side 29. In the exemplary embodiment shown, the auxiliary carrier 5 between adjacent semiconductor chips 2 is free of the filling material in some areas.

Subsequently, the semiconductor chips 4 with the fillets 4 adjoining the semiconductor chips 2 in the lateral direction are deformed by a molding compound to form a package body assembly 30 ( 1C ). In the exemplary embodiments shown, the package body assembly 30 also covers the rear side 29 of the semiconductor chips 2. The package body assembly 30 is formed, for example, by means of a casting method.

In a subsequent manufacturing step, the composite housing body 30 can be thinned from the side facing away from the auxiliary carrier 5, for example by means of a mechanical process such as grinding.

Instead of overmolding the semiconductor chips 2 on the rear side 29 and subsequent thinning of the package body assembly 30, the package body assembly can also be formed in such a way that the rear sides 28 of the semiconductor chips 2 are exposed. A film-assisted casting method (film-assisted molding) can be used for this purpose, for example.

In 1D 1 shows the package body assembly 30 with the semiconductor chips 2 embedded therein after the auxiliary carrier 5 has been removed. After the auxiliary carrier 5 has been removed, the front side of the semiconductor chip 28 is accessible, for example for making electrical contact with the semiconductor chip. For the sake of simplicity, this is not shown in the figures and, like possible configurations of the semiconductor chips, is illustrated on the basis of FIG 4A and 4B explained.

For singulation into semiconductor components 1, the package body assembly 30 can be severed along singulation lines 7. This can be done, for example, mechanically, for example by means of sawing, chemically, for example by means of etching, and/or by means of coherent radiation, for example by laser ablation.

In the case of a fillet 4 designed to be radiation-transmissive, radiation can also exit through the side faces 20 of the semiconductor chip 2 during operation of the semiconductor component. An interface 31 existing between the groove 4 and the housing body 3 emerging from the housing body assembly can form a reflector surface, through which the radiation exiting at the side can be bundled.

The filling material 40 can also be mixed with a radiation conversion material that converts radiation generated during operation of the semiconductor chips 2, for example blue radiation, at least partially into secondary radiation, for example into yellow radiation.

In the case of a radiation-transmissive fillet 4, the interface 31 is reflective and has a reflectivity of at least 80%, for example. For example, the case body 3 is formed by a material mixed with white pigments.

Alternatively, the fillet 4 itself can also be formed from a filling material that has a high reflectivity, for example a reflectivity of at least 80%, for the radiation generated in the semiconductor chip. The fillet thus also protects the housing body 3 from damage caused by radiation generated in the semiconductor chip during operation.

The material for the housing body 3 can be chosen independently of the optical properties and its radiation stability. In this case, for example, a black epoxy material (“black epoxy”) is suitable for the housing body 3 . Such a material is available particularly cheaply due to its widespread use in electronics and is characterized by good processability.

The rear side 29 of the semiconductor chips 2 is exposed on a mounting surface 15 of the semiconductor component 1 so that the waste heat generated in the semiconductor chip can be efficiently dissipated via the mounting surface 15 during operation. Deviating from this, however, it is also conceivable for the material of the housing body 3 to cover the rear side 29 of the semiconductor chip 2 .

On the side facing away from the mounting surface, the housing body does not protrude in the vertical direction, or at least does not protrude significantly beyond the semiconductor chip. A particularly compact design is simplified in this way.

That in the 2A until 2E illustrated second embodiment essentially corresponds to in connection with 1A until 1E described first embodiment. In contrast to this, an auxiliary material 41 is applied to the auxiliary carrier 5 even before the semiconductor chips 2 are attached to the carrier 5 ( 2A ). The auxiliary material can be applied, for example, by means of printing or a jetting process.

The semiconductor chips 2 are then pressed into the auxiliary material 41 so that the auxiliary material 41 wets the side faces 20 of the semiconductor chips 2 . A meniscus 410 forms in the auxiliary material 41 between adjacent semiconductor chips 2 . In the area of the meniscus 410, the auxiliary material 41 has a smaller vertical extent than in the area in which the auxiliary material adjoins the semiconductor chips 2 ( 2 B ).

The auxiliary material 41 is therefore also used to attach the semiconductor chips 2 to the auxiliary carrier 5.

A particularly suitable auxiliary material 41 is a material that can be easily and reliably removed in a later method step without the risk of damage to the other elements.

As in 2C shown, the semiconductor chips 2 with the auxiliary material 41 are subsequently shaped by a molding compound to form a package body assembly 30 . This can be related to like 1C described. Due to the auxiliary material 41, the housing body assembly 30 does not adjoin the semiconductor chips 2 or at least adjoins an area occupancy of at most 20%, preferably at most 10%.

2D shows a method stage in which the auxiliary carrier 5 and the auxiliary material 41 have been removed. Depending on the auxiliary material, for example a solvent, an etching method or a thermal treatment in which the auxiliary material 41 melts is suitable for removing the auxiliary material.

The channel 4 formed by means of the auxiliary material 41 can subsequently be filled with a filling material 40 . This can be done, for example, by means of a dosing process, for example by means of a dispenser, or by means of a pouring process.

Regarding their optical properties, the throat 4 in connection with 1A described be trained. Alternatively, it is also conceivable that the channel 4 is not filled with a filling material but remains free. As a result, the difference in refractive index on the side surface 20 of the semiconductor chip 2 is maximized. Because of Total reflection, the proportion of radiation that can exit through the side surface 20 of the semiconductor chip 2 is thus minimized.

This in 3A until 3E illustrated third embodiment corresponds essentially to that in connection with 1A until 1E described first embodiment. In contrast to this, the semiconductor chips 2 ( 3A ) is first formed by a molding compound to form a housing body assembly 30 in such a way that the molding compound adjoins the side surfaces 20 of the semiconductor chips 20 over the entire surface. In contrast to the first exemplary embodiment, the semiconductor chips 2 are placed in such a way that the rear side 29 of the semiconductor chips faces the auxiliary carrier 5 .

As in the 3B and 3C shown, the housing body assembly 30 can in turn be formed in such a way that the semiconductor chips 2 are first completely embedded in the molding compound for the housing body assembly 30 and the housing body assembly is subsequently thinned such that the front side 28 of the semiconductor chips 2 is exposed.

Subsequently, material of the package body assembly 30 adjoining the side faces 20 of the semiconductor chips is removed in regions. This can be done, for example, by means of laser ablation. In the vertical direction, the fillet 4 extends only in regions over the side surface 20 of the semiconductor chips 2, so that even after the fillet 4 has been formed, material of the package body assembly 30 is adjacent to the side surface 20. The larger the area in which the package body assembly 30 adjoins the semiconductor chips 2, the easier it is to achieve a mechanically stable connection between the semiconductor chips 2 and the package body assembly 30. On the other hand, the decoupling efficiency can be improved by a greater vertical extent of the grooves 4 . The area coverage with which the package body assembly 30 covers the side faces 20 of the semiconductor chip 2 after the formation of the fillets 4 is preferably at most 50%.

After forming the throats 4, they can as in connection with 2E be filled as described or remain unfilled.

An embodiment of a semiconductor device is in 4B in plan view and in schematic sectional view along the line AA 'in 4A shown. The semiconductor component 1 has a semiconductor chip 2 . The semiconductor chip 2 comprises a semiconductor body 21 with an active region 22 provided for generating radiation and a substrate 25. A mirror layer 26 is formed on a rear side 29 of the semiconductor chip 2. The mirror layer can be, for example, a metallic mirror layer or a Bragg mirror with a plurality of dielectric layers. On a front side 28, the semiconductor chip 2 has two connection areas for making electrical contact with the semiconductor chip (not explicitly shown).

The substrate 25 is, for example, the growth substrate for the semiconductor body 21. For example, a radiation-transmissive substrate such as sapphire or silicon carbide is suitable as the substrate. The semiconductor chip 2 is enclosed by a housing body 3 in the lateral direction. A channel 4 is formed between the housing body 3 and the semiconductor chip 2 . The fillet 4 surrounds the semiconductor chip 2 in the lateral direction along the entire circumference. Furthermore, the fillet 4 has a lateral extent that decreases as the distance from the radiation exit area 10 of the semiconductor component 1 increases. The throat 4 can be as related to 1E described to be radiation-transmissive or reflective.

The semiconductor component 1 has a first contact 61 and a second contact 62 on a mounting surface 15 opposite the radiation exit surface 10 . By applying external electrical voltages between these contacts, charge carriers can be injected from different sides into the active region 22 and recombine there with the emission of radiation. The first contact 61 and the second contact 62 are each electrically conductively connected to the semiconductor chip 2 via vias 63 through the housing body 3 and connecting lines 64 . The connecting lines 64 extend in the lateral direction beyond the side surface 20 of the semiconductor chip 2 and cover the housing body 3 in regions. In the exemplary embodiment described, the connecting line 64 is designed as a coating. Deviating from this, however, a wire bond connection can also be used. On the side opposite the mounting area 15, the semiconductor component 1 can have a radiation conversion element (not explicitly shown).

However, the geometric arrangement of the contacts and the contact routing to the semiconductor chip 2 can be varied within limits. For example, a semiconductor chip can also be used which has a front-side and a rear-side connection area. In this case, only one via 63 is required. A semiconductor chip with two rear connection areas is also conceivable. For example, the semiconductor chip 2 can also be embodied as a thin-film semiconductor chip with an electrically conductive substrate 25 .

In order to determine the achievable efficiency, simulations were carried out, which were based on a semiconductor chip with a transparent substrate 25, so that radiation can also be coupled out to a considerable extent from the side surface 20 of the semiconductor chip. As a starting point for the simulations, a reference structure was taken as a basis, in which the semiconductor chip adjoins a material with a reflectivity of 92% on the back and on the side surfaces. A radiation conversion material is formed on the front side of the semiconductor chip. An increase in efficiency of 6% can be achieved by a groove running around the semiconductor chip, whose boundary surface facing away from the semiconductor chip is inclined at an angle of 45° to the side surface of the semiconductor chip and which is filled with a radiation conversion material.

If the fillet is not filled with a radiation conversion material but with a silicone with a high refractive index of around 1.5, the efficiency can be achieved by around 6.25% compared to the reference structure. The simulations were each based on a semiconductor chip height of 150 µm.

The fillet described can therefore achieve a significant increase in the efficiency of the semiconductor component in a way that is technically simple to implement.

Claims (22)

Optoelectronic semiconductor component (1) having a mounting surface (15) and a radiation exit surface (10) lying opposite the mounting surface, wherein - the semiconductor component has a semiconductor chip (2) provided for generating radiation; - The semiconductor component has a housing body (3) surrounding the semiconductor chip in a lateral direction; - the semiconductor chip is free of material of the housing body on the radiation exit area; and - A fillet (4) adjoins a side face (20) of the semiconductor chip, which fillet is formed between the housing body (3) and the semiconductor chip (2); - the semiconductor chip comprises a semiconductor body with an active region (22) provided for generating radiation and a substrate (25) on which the semiconductor body is arranged, the substrate (25) being a growth substrate for the semiconductor layers of the semiconductor body; - the optoelectronic semiconductor component has a first contact (61) and a second contact (62) on the mounting surface (15), at least one of the contacts (61, 62) being electrically conductively connected to the semiconductor chip (2) via a via (63). is; and - The via (63) does not run through the groove (4). semiconductor device claim 1 , wherein the fillet (4) runs along the entire circumference of the semiconductor chip. semiconductor device claim 1 or 2 , wherein the groove (4) tapers in the direction of the mounting surface as viewed from the radiation exit surface. Semiconductor component according to one of the preceding claims, wherein the semiconductor chip (2) is free of material of the housing body (3) on the mounting surface (15). Semiconductor component according to one of the preceding claims, in which the fillet (4) has a filling material (40) which is transparent to the radiation to be generated by the semiconductor chip (2). Semiconductor component according to one of the preceding claims, in which the fillet (4) is not filled with a radiation conversion material. Semiconductor component according to one of the preceding claims, in which the housing body (3) is formed by a material to which white pigments have been added. Semiconductor component according to one of the preceding claims, in which the housing body (3) has a reflectivity of at least 55% for the radiation to be generated by the semiconductor chip (2). Semiconductor component according to one of the preceding claims, in which the fillet (4) has a convex curvature as seen from the radiation exit surface (10). Semiconductor component according to one of the preceding claims, in which the semiconductor chip (2) has a mirror layer (26). semiconductor device claim 10 , In which the mirror layer (26) is a metallic mirror layer on a rear side (29) of the semiconductor chip (2). Semiconductor component according to one of the preceding claims, in which the fillet (4) extends in the vertical direction over the entire height of the semiconductor chip (2). Semiconductor component according to one of the preceding claims, in which the fillet (4) extends in the vertical direction over only part of the semiconductor chip (2). Semiconductor component according to one of the preceding claims, in which the semiconductor chip has two connection areas for electrical contacting, which are arranged on a side of the semiconductor body which is remote from the growth substrate. Semiconductor component according to one of the preceding claims, which has a radiation conversion element on a side opposite the mounting area (15). Semiconductor component according to one of the preceding claims, in which the first contact (61) and the second contact (62) are each electrically conductively connected to the semiconductor chip (2) via a via (63). semiconductor device Claim 16 , in which the vias are each electrically conductively connected to the semiconductor chip via a connecting line (64), the connecting lines (64) extending in the lateral direction beyond the side surface (20) of the semiconductor chip (2). semiconductor device Claim 17 , in which the connecting line (64) is designed as a coating. Semiconductor component according to one of the preceding claims, in which the material of the housing body covers a rear side (29) of the semiconductor chip. Semiconductor component according to one of the preceding claims, in which the housing body (3) is part of a housing body assembly. Semiconductor component according to one of the preceding claims, in which the housing body (3) has a molding compound. Semiconductor component according to one of the preceding claims, in which the groove (4) directly adjoins the housing body (3).

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