OPTOELECTRONIC COMPONENT

Abstract

Optoelectronic component with: - comprising a housing (14): - a conductor frame (1) having two external electrical contact points (2) and two contact bridges (3), - a housing body (12) in which the conductor frame (1) is embedded, wherein - each contact bridge (3) extends laterally from one of the external electrical contact points (2) to a mounting surface (13) of the housing (14), so that contact surfaces (10) of the contact bridges (3) are exposed on the mounting surface (13), - an optoelectronic semiconductor chip (5), wherein the optoelectronic semiconductor chip (5) is mounted on an electrical connection point (4) of the conductor frame (1) and is electrically connected to two further electrical connection points (6) via a bond wire, - an optical element (21) arranged on the mounting surface (13) of the housing (14), wherein - electrical contact structures (22) of the optical element (21) are electrically connected to the contact surfaces (10) of the contact bridges (3).

Description

[0001] An optoelectronic component is specified.

[0002] US Patent 2012 / 0181555A1 relates to an optoelectronic component comprising an optoelectronic semiconductor chip and an optical element, as well as an associated manufacturing process. The aim is to enable efficient manufacturing of the component while simultaneously improving its optical quality and thermal properties.

[0003] WO 2020 / 027 721 A1 relates to an optical package comprising a light source (e.g. a VCSEL), an optical element, and a conductor frame for contacting the optical element, which is arranged on a mounting surface above the bottom surface of the package.

[0004] WO 2020 / 038 776 A1 relates to an optoelectronic device for generating laser radiation comprising an optoelectronic component (e.g. a VCSEL) and an optical element (e.g. a diffractive optic) as well as a method for controlling an optoelectronic device, wherein it is to be ensured that laser radiation is only emitted when the optical element is in the beam path of the laser radiation.

[0005] DE 10 2017 123 413 A1 relates to an optoelectronic semiconductor component and a manufacturing process for an optoelectronic semiconductor component with a hermetically sealed housing that can be manufactured efficiently.

[0006] The aim is to specify an optoelectronic component in which the functionality of an optical element encompassed by the optoelectronic component can be easily tested.

[0007] The problem is solved by an optoelectronic component with the features of claim 1.

[0008] Advantageous embodiments and further developments of the optoelectronic component are the subject of the dependent claims.

[0009] The optoelectronic component includes a housing.

[0010] The housing includes a conductor frame that has two external electrical contact points and two contact bridges.

[0011] The housing comprises a housing body in which the conductor frame is embedded. Preferably, the conductor frame is embedded in the housing body such that only one surface of the conductor frame, for example for electrical contact, is freely accessible from the outside. This surface of the conductor frame is preferably flush with the surface of the housing body.

[0012] Particularly preferably, the external electrical contact points are arranged on a bottom surface of the housing. For example, the external electrical contact points are flush with the surrounding housing body.

[0013] Each contact bridge extends laterally from one of the external electrical contact points to a mounting surface of the housing, so that the contact surfaces of the contact bridges are exposed on the mounting surface. The mounting surface is designed and intended for mounting an optical element.

[0014] Preferably, the contact bridges extend from the external electrical contact points through the housing body to the mounting surface. The mounting surface is located opposite the bottom surface of the housing body. In other words, the contact bridges establish an electrically conductive connection from the bottom surface of the housing to the mounting surface of the housing. Particularly preferably, the contact bridges are formed integrally with the external electrical contact points.

[0015] According to another embodiment, the housing comprises a housing wall that surrounds the mounting surface. For example, the housing wall completely surrounds the mounting surface. However, it is also possible for the housing wall to have openings. The housing wall is particularly preferably designed and configured to form a boundary for an optical element that is placed on the mounting surface.

[0016] According to another embodiment of the housing, the contact ribs have a thinner profile than the external electrical contacts. For example, the external electrical contacts have a thickness between 200 and 300 micrometers inclusive. The contact ribs, for example, have a thickness between 80 and 150 micrometers inclusive.

[0017] The conductor frame includes an electrical connection point designed and configured for mounting an optoelectronic semiconductor chip. This electrical connection point is, for example, designed for soldering. The conductor frame also includes further electrical connection points designed and configured for electrically contacting the optoelectronic semiconductor chip using a bond wire.

[0018] According to another embodiment of the housing, the conductor frame comprises or is made of a metal. For example, the conductor frame comprises or is made of copper. Furthermore, it is also possible that the conductor frame has at least a partial bondable coating. The bondable coating comprises, for example, gold or consists of gold.

[0019] For example, the housing body is made of or consists of a plastic. For example, the plastic material is an epoxy resin. Preferably, the housing body is black.

[0020] The housing offers a high degree of design freedom. Furthermore, the housing is advantageously designed to be particularly mechanically robust, especially since the conductor frame is largely embedded within the housing body.

[0021] The housing can be manufactured using a method as described below. The method itself is not part of the invention. Features and embodiments described only in connection with the housing may also be present in the method, and vice versa.

[0022] According to a method for manufacturing a housing for an optoelectronic component, a conductor frame is provided. The conductor frame has two external electrical contact points and two contact bridges, each contact bridge extending laterally from an external electrical contact point. Preferably, the external electrical contact points and the contact bridges are located in a main extension plane of the conductor frame when the frame is provided.

[0023] According to one embodiment of the method, the contact bridges are bent out of the main extension plane of the conductor frame.

[0024] In this method, a housing body is produced that embeds the conductor frame, such that each contact bridge extends laterally from one of the external electrical contact points to a mounting surface of the housing, leaving the contact surfaces of the contact bridges exposed on the mounting surface. Particularly preferably, the housing body is produced after the contact bridges have been bent from the main extension plane of the conductor frame.

[0025] According to a preferred embodiment of the method, the housing body is produced by foil-assisted molding (FAM).

[0026] In film-assisted molding, a tool with at least two halves is used, which form a cavity when closed. One surface of each half is at least partially coated with a film, such as a plastic film. A workpiece, in this case, for example, the ladder frame, is placed into one of the halves. The halves are then closed, so that the workpiece is located in the cavity. A housing material, initially liquid, is then injected into the cavity and cured, so that the housing material is molded to the workpiece according to the shape of the mold. In this case, the housing body is formed around the ladder frame. In the next step, the workpiece is demolded from the mold. Due to the film coating on the mold halves, demolding is particularly easy and defect-free.

[0027] Foil-assisted forming has the advantage that the probability of the contact surfaces of the contact bridges being contaminated with material of the housing body during the production of the housing body is reduced.

[0028] According to a further embodiment of the method, recesses are created in the mounting surface of the housing body during its production. Each contact surface is located on the bottom surface of a recess. In other words, each contact surface is surrounded by a recess. Specifically, the recesses in the mounting surface of the housing body are created during film-assisted molding. In film-assisted molding, the contact surfaces of the contact ridges are pressed into the film lining the tool. This is how the recesses are formed. In other words, the recesses serve as evidence for the use of the method described herein.

[0029] According to another embodiment of the method, the contact surfaces are cleaned after the housing body has been produced, for example with the help of a laser or by water jet-guided particle blasting (English: “wetblasting”).

[0030] According to a further embodiment of the method, the contact ridges in the tool are held under tension during the production of the housing body. For this purpose, the contact ridges preferably have an increased length. This advantageously reduces, at least to some extent, the contamination of the contact surfaces of the contact ridges with housing material.

[0031] According to a further embodiment of the method, the contact bridges are provided with an additional bend, thus increasing the contact area. This also advantageously reduces, at least to some extent, the contamination of the contact surfaces of the contact bridges with housing material.

[0032] According to a further embodiment of the method, the conductor frame is produced by first providing a sheet metal blank and then etching it to form the conductor frame. For example, a photoresist mask with the desired inverse structure is applied before etching. The sheet metal blank is then etched through the photoresist mask, preferably using a wet chemical process. Subsequently, the conductor frame can be provided with a bondable metallic coating, for example, by electroplating.

[0033] According to another embodiment of the method, the contact bridges are etched so that they have a smaller thickness than the external electrical contact points.

[0034] If the contact bridges have a smaller thickness than the external electrical contact points, the contact bridges are easily bendable, while the mechanical stability of the conductor frame is not affected by the greater thickness of the external electrical contact points.

[0035] According to a further embodiment of the method, the conductor frame has a support frame that surrounds the external electrical contact points, preferably completely. Particularly preferably, the support frame also surrounds the electrical connection point for the optoelectronic semiconductor chip and the other electrical connection points for the bond wires. Particularly preferably, the contact bridges are not connected to the support frame. The support frame contributes to the mechanical stability of the workpiece during the formation of the housing body. Particularly preferably, the support frame is no longer enclosed by the finished housing.

[0036] According to a further embodiment of the method, the conductor frame has anchor ribs for mechanical stabilization. Preferably, the anchor ribs connect the support frame to the electrical connection point for the optoelectronic semiconductor chip and / or to the other electrical connection points for the bond wires. The mechanical anchor ribs are particularly preferably no longer enclosed by the finished housing.

[0037] According to another embodiment, the housing manufacturing process is carried out in a batch process. In this process, several housings are manufactured in parallel. For example, the conductor frame is comprised of a panel containing a multitude of similar or identical conductor frames. Advantageously, a comparatively high packing density can be achieved on the panel using the conductor frame described here.

[0038] In the batch process, numerous conductor frames are simultaneously fitted with a housing body, for example, by foil-assisted forming. For instance, after the housing body has been produced, the encased conductor frames are separated in a separation process.

[0039] The optoelectronic component comprises a housing as previously described. The external electrical contact points of the housing are preferably designed to electrically contact the optoelectronic component from the outside.

[0040] The optoelectronic component comprises an optoelectronic semiconductor chip.

[0041] Furthermore, the optoelectronic component includes an optical element arranged on the mounting surface of the housing, with electrical contact structures of the optical element being electrically connected to the contact surfaces of the contact bridges. In this way, it can be easily determined whether the optical element is still enclosed within the optoelectronic component or not by electrically contacting the external electrical contact points. The functionality of the optical element can also be verified in this way.

[0042] The optical element can be a lens or a diffuser. Its primary purpose is to adjust the emission characteristics of the optoelectronic semiconductor chip as desired.

[0043] The electrical contact structures of the optical element are preferably in direct physical contact with the contact surfaces of the contact bridges. In this way, the electrical contact is established.

[0044] According to another embodiment of the optoelectronic component, the optoelectronic semiconductor chip is a radiation-emitting semiconductor chip that emits electromagnetic radiation, preferably visible light, from a radiation-emitting surface. Preferably, the radiation-emitting semiconductor chip is a surface-emitting semiconductor laser chip, such as a VCSEL (short for "vertical cavity surface-emitting laser").

[0045] If the optoelectronic component includes a surface-emitting semiconductor laser chip, the optical element is preferably designed to adjust the far field of the semiconductor laser chip in a suitable manner. For example, the optical element is designed to adjust the power of the electromagnetic radiation from the semiconductor laser chip per unit area to a desired value that is so low as to cause damage to the human eye. In this context, it is particularly important to be able to easily verify, before operating the optoelectronic component, that the optical element is present and undamaged.

[0046] Preferably, the optical element incorporates electrically conductive contact structures that allow its condition to be checked via resistance measurement. For this purpose, the optical element's electrical contact structures must be electrically connected externally. Curved contact bridges are provided for this purpose, establishing an electrically conductive connection from the mounting surface of the housing to the external electrical contact points on the rear. The contact surfaces of the curved contact bridges are preferably in direct electrically conductive contact with the optical element's electrical contact structures, thus enabling easy electrical contact via the external electrical contact points.

[0047] The housing manufacturing process described here allows for the particularly simple production of such housings. Conventional housings, in which electrical contacts are realized on a mounting surface using, for example, multilayer ceramics or printed circuit boards, or by inserting metallic posts into the housing body that are subsequently exposed, for example, by grinding, are generally significantly more expensive or limited in design freedom.

[0048] The optoelectronic semiconductor chip is mounted on an electrical connection point of the conductor frame. Furthermore, the optoelectronic semiconductor chip is electrically connected to two other electrical connection points via a bond wire.

[0049] According to another embodiment, the optoelectronic component includes an additional diode for protection against electrostatic discharges (ESD diode, short for "electrostatic discharge diode").

[0050] According to one embodiment, the electrical contact structure at least partially surrounds an optically active area of ​​the optical element. The optically active area comprises, for example, a lens array. The electrical contact structures of the optical element are, for example, a conductive track. The electrical contact structures are, for example, deposited onto the optical element as a metallic layer. Furthermore, it is also possible for the electrical contact structure to be formed from an electrically conductive paste or ink.

[0051] The optoelectronic component can be manufactured, for example, using the method described below, which is not part of the invention.

[0052] A housing as described here is provided in a process for manufacturing an optoelectronic component.

[0053] According to one embodiment of the method, an optoelectronic semiconductor chip is applied to a mounting surface of the housing.

[0054] According to the procedure, an optical element is applied to the mounting surface of the housing.

[0055] This process can also be carried out in a batch process, i.e., a process in which several optoelectronic components are manufactured in parallel. For this purpose, the process steps of a batch process for manufacturing a large number of housings, as already described above, are performed. However, the housings are generally not separated after the housing bodies have been produced. Instead, optoelectronic semiconductor chips are typically deposited onto the electrical contact points provided for their mounting. In a subsequent step, the optoelectronic semiconductor chips are usually electrically contacted, for example, using bond wires. Finally, the resulting assembly can be separated into individual optoelectronic components. Then, an optical element can be mounted on each mounting surface of each housing.

[0056] Furthermore, it is also possible that all housings are first fitted with the optical element and the optoelectronic components are only separated afterwards.

[0057] The optoelectronic component can be used, for example, in motor vehicles, consumer electronics devices, or sensors. If the optoelectronic component includes a surface-emitting semiconductor laser chip as a light source, one possible application is time-of-flight measurement.

[0058] The ladder frame preferably contains additional structures in the edge area that surrounds the panel, such as recesses for alignment.

[0059] Further advantageous embodiments and developments of the optoelectronic component result from the exemplary embodiments described below in conjunction with the figures.

[0060] Based on the schematic representations of the Fig. 1, Fig. 2 to Fig. 3 A method for manufacturing a housing for an optoelectronic component, which is not part of the invention, is explained in more detail.

[0061] Fig. Figure 4 shows a schematic sectional view of a housing of the component from Fig. 9.

[0062] Based on the schematic representations of the Fig. 5 and Fig. Section 6 describes in more detail a method for manufacturing a housing for an optoelectronic component, which is not part of the invention.

[0063] Based on the schematic representations of the Fig. 7 and Fig. Section 8 describes in more detail a method for manufacturing an optoelectronic component, which is not part of the invention.

[0064] Fig. Figure 9 shows a schematic sectional view of an optoelectronic component according to an exemplary embodiment.

[0065] Identical, similar, or similarly functioning elements are marked with the same reference symbols in the figures. The figures and the relative sizes of the elements depicted within them are not to be considered to scale. Rather, individual elements, particularly layer thicknesses, may be exaggerated for clarity and / or better understanding.

[0066] In the procedure according to the Fig. 1, Fig. 2 to Fig. 3, which is not part of the invention, a ladder frame 1 is provided in a first step ( Fig. 1).

[0067] The conductor frame 1 has two external electrical contact points 2 and two contact bridges 3. Furthermore, the conductor frame 1 includes an electrical connection point 4 for mounting an optoelectronic semiconductor chip 5 and two further electrical connection points 6 for electrical contacting with a bond wire each. The conductor frame 1 also has a support frame 7. The support frame 7 completely surrounds the electrical connection point 4 for mounting the optoelectronic semiconductor chip 5, the further electrical connection points 6 for receiving the bond wires, and the two external electrical contact points 2.

[0068] Furthermore, the conductor frame 1 has mechanical anchor webs 8 which mechanically and stably connect the electrical connection point 4 for mounting the optoelectronic semiconductor chip 5, the other electrical connection points 6 for receiving the bond wires and the two external electrical contact points 2 to the support frame 7.

[0069] Each contact bridge 3 extends laterally from an external electrical contact point 2. However, unlike the anchor bridges 8, the contact bridges 3 are not connected to the support frame 7.

[0070] For example, the conductor frame 1 is made of copper and is at least partially coated with gold.

[0071] Fig. Figure 2 shows a schematic sectional view along line AA of the ladder frame 1 of the Fig. 1. A contact bridge 3 extends laterally from each external electrical contact point 2. The two contact bridges 3 each have a smaller thickness than the external electrical contact points 2. The external electrical contact points 2 and the contact bridges 3 are flush with a surface of the conductor frame 1. The external electrical contact points 2 and the contact bridges 3 initially lie in a main plane of extension of the conductor frame 1.

[0072] In a next step, the contact bridges 3 are bent out of the main extension plane 9 of the conductor frame 1 ( Fig. 3) Particularly preferably, the contact surfaces 10 of the contact webs 3, which in this case are end surfaces of the contact webs 3, are located in a common principal extent plane. The common principal extent plane 11 of the contact surfaces 10 runs parallel to the principal extent plane 9 of the conductor frame 1.

[0073] In a next step, a housing body 12 is produced that encloses the conductor frame 1. Each contact bridge 3 extends laterally from one of the external electrical contact points 2 to a mounting surface 13 of the housing 14, with the contact surfaces 10 of the contact bridges 3 being exposed on the mounting surface 13. The housing body 12 can be produced, for example, by foil-assisted forming. A black housing material is particularly preferred for the housing body 12.

[0074] The conductor frame 1 is embedded in the housing body 12 in such a way that only surfaces of the conductor frame 1 are exposed for electrical contacting, namely surfaces of the external electrical contact points 2 and the contact surfaces 10 of the contact bridges 3.

[0075] The housing 14 according to the Fig. 4 can be used, for example, based on the Fig. 1, Fig. 2 to Fig. The 3 described methods are used to generate the products.

[0076] The housing 14 of the optoelectronic component according to the Fig. 4 has a black housing body 12 in which a conductor frame 1 is embedded. The conductor frame 1 includes external electrical contact points 2. From each external electrical contact point 2, a contact bridge 3 extends laterally to a mounting surface 13 of the housing 14. Contact surfaces 10 of the contact bridges 3 are exposed on the mounting surface 13.

[0077] The mounting surface 13 has recesses 15, with each contact surface 10 being arranged on a base surface 16 of a recess 15. The recesses 15 are produced during the manufacture of the housing body 12 by foil-assisted forming, when the contact ridges 3 are pressed into a foil with which a tool is lined.

[0078] The contact bridges 3 form the housing 14 of the Fig. 4 an electrically conductive connection from the mounting surface 13 of the housing 14 to a rear side of the housing 14, which is opposite the mounting surface 13 and where the external electrical contact points 2 are freely accessible. The external electrical contact points 2 are flush with a surface of the housing body 12.

[0079] The mounting surface 13 of the housing 14 of the Fig. 4 is further surrounded by a housing wall 17, which completely surrounds the mounting surface 13 in this case.

[0080] In the procedure according to the Fig. 5 and Fig. 6, which is not part of the invention, is different from the method according to the Fig. 1 and Fig. 3 a panel 18 with a plurality of identical ladder frames 1 provided ( Fig. 5) In the procedure according to the Fig. 5 and Fig. Therefore, in step 6, this is a batch process.

[0081] The ladder frames 1, for example, are designed as already shown by the Fig. As already described, the multiple ladder frames 1 are completely surrounded by a common outer frame 19. The common outer frame 19 includes, for example, markings for adjustment (not shown).

[0082] In a next step, the conductor frames 1 are surrounded by a multitude of housing bodies 12, for example by means of foil-assisted forming. Fig. Figure 6 shows an exemplary top view of a ladder frame 1 embedded in a black housing body 12.

[0083] The housings 14 are then separated, resulting in a large number of housings 14, as shown, for example, by the Fig. 4 already described. In particular, a support frame 7 of each ladder frame 1 is no longer enclosed by the finished housing 14, but is removed during singulation.

[0084] In the process for manufacturing an optoelectronic component according to the Fig. 7 and Fig. 8, which is not part of the invention, a housing 14 is first provided, as shown in the Fig. 4 has already been described.

[0085] In a next step, an optoelectronic semiconductor chip 5 is applied to the electrical connection point 4 of the conductor frame 1, which is intended to accommodate the optoelectronic semiconductor chip 5 ( Fig. 7) The optoelectronic semiconductor chip 5 is electrically contacted with bond wires (not shown).

[0086] The optoelectronic semiconductor chip 5 is, for example, a surface-emitting semiconductor laser chip, such as a VCSEL. During operation, the surface-emitting semiconductor laser chip 5 emits electromagnetic radiation, preferably visible light, from a radiation emission surface 20.

[0087] In the next step, an optical element 21, as schematically shown in Fig. The optical element 21, as shown in Figure 8, is mounted on a mounting surface 13 of the housing 14, which is surrounded by a housing wall 17. The optical element 21 has an electrical contact structure 22 that partially surrounds an optically active area 23. The electrical contact structures 22 of the optical element 21 are, for example, a conductor track. The electrical contact structures 22 are, for example, vapor-deposited as a metallic layer. Furthermore, it is also possible that the electrical contact structure 22 is formed from an electrically conductive paste or an electrically conductive ink. The optically active area 23 has, for example, a lens array.

[0088] The optoelectronic component according to the embodiment of the Fig. 9 can, for example, be produced using a process as described in the Fig. 7 and Fig. 8 was described.

[0089] The optoelectronic component according to the embodiment of the Fig. 9 has a housing 14, as can be seen from the Fig. As already described in section 4, the optoelectronic component also includes an optoelectronic semiconductor chip 5, for example, a surface-emitting semiconductor laser chip. Furthermore, an optical element 21 is mounted on a mounting surface 13 of the housing 14. The optical element 21 is surrounded by a housing wall 17, which secures the optical element 21. Electrical contact structures 22 of the optical element 21 are in direct contact with the contact surfaces 10 exposed on the mounting surface 13, thus forming an electrically conductive connection.

[0090] The optical element 21 adjusts the emission characteristics of the optoelectronic semiconductor chip 5 in a desired manner. If the optoelectronic semiconductor chip 5 is a surface-emitting semiconductor laser chip, the far field of the surface-emitting semiconductor laser chip is specifically adjusted to a desired value that does not harm the human eye. By measuring the resistance across the external electrical contacts 22 on the back side of the optoelectronic component, it can be advantageously and easily determined whether the optical element 21 is still enclosed by the component or not. Reference symbol list 1 ladder frame 2 external electrical contact points 3 contact bridge 4 electrical connection points 5 Semiconductor chips 6 additional electrical connection points 7 support frames 8 Anchorage 9 Main extension plane of the ladder frame 10 Contact area 11 Main extent plane of the contact surfaces 12 Housing bodies 13 Mounting surface 14 cases 15 Exclusion 16 floor area 17 Housing wall 18 Panel 19 common outer frame 20 Radiation emission area 21 optical element 22 electrical contact structure 23 optically active areas

Claims

[1] Optoelectronic component with: - comprising a housing (14): - a conductor frame (1) having two external electrical contact points (2) and two contact bridges (3), - a housing body (12) in which the conductor frame (1) is embedded, wherein - each contact bridge (3) extends laterally from one of the external electrical contact points (2) to a mounting surface (13) of the housing (14), so that contact surfaces (10) of the contact bridges (3) are exposed on the mounting surface (13), - an optoelectronic semiconductor chip (5), wherein the optoelectronic semiconductor chip (5) is mounted on an electrical connection point (4) of the conductor frame (1) and is electrically connected to two further electrical connection points (6) via a bond wire, - an optical element (21) arranged on the mounting surface (13) of the housing (14), wherein - electrical contact structures (22) of the optical element (21) are electrically connected to the contact surfaces (10) of the contact bridges (3). [2] Optoelectronic component according to the previous claim comprising a housing wall (17) surrounding the mounting surface (13). [3] Optoelectronic component according to one of the above claims, wherein the contact bridges (3) have a lesser thickness than the external electrical contact points (2). [4] Optoelectronic component according to one of the above claims, wherein the housing body (12) is black. [5] Optoelectronic component according to one of the above claims, wherein each contact surface (10) is arranged on a bottom surface (16) of a recess (15). [6] Optoelectronic component according to one of the above claims, wherein the conductor frame (1) has a support frame (7) that surrounds the external electrical contact points (2). [7] Optoelectronic component according to one of the above claims, wherein the conductor frame (1) has anchor webs (8) for mechanical stabilization. [8] Optoelectronic component according to one of the above claims, wherein the electrical contact structures (22) are in direct contact with the contact surfaces (10) of the contact bridges (3). [9] Optoelectronic device according to any of the above claims, wherein the optoelectronic semiconductor chip (5) is a surface-emitting semiconductor laser chip.

Images