OPTOELECTRONIC MODULE AND A PROCESS FOR THE PRODUCTION OF AN OPTOELECTRONIC MODULE

Abstract

An optoelectronic module (100) is defined, comprising at least one semiconductor chip (10) provided for emitting electromagnetic radiation and at least one holding device (20) which is adapted to fix in place a device (50) for encoding at least one optical or electronic parameter of the optoelectronic module (100). Furthermore, a process for the production of the optoelectronic module (100) is defined.

Claims

1. A process for the production of an optoelectronic module having the steps of: a) providing an optoelectronic module having at least one semiconductor chip provided for emitting electromagnetic radiation; b) measuring an optical or electronic parameter of the optoelectronic module; c) providing an encoding element, especially in the form of a surface-mountable device, wherein the encoding element carries information relating to the optical or electronic parameter of the optoelectronic module; and d) fixing the encoding element in place in or on the optoelectronic module.

2. The process according to claim 1, wherein in step a) an optoelectronic module is provided and in step d) the encoding element is inserted or pushed into the fixing position along the insertion direction, wherein the optoelectronic module comprises: at least one semiconductor chip provided for emitting electromagnetic radiation; and at least one holding device which is adapted to fix in place the encoding element, wherein the holding device comprises at least one locking device which is movable between a locking position and a receiving position, wherein in the receiving position the encoding element can be displaced along an insertion direction towards a fixing position inside the holding device, and wherein in the locking position the locking device is adapted to effect at least partial fixing of the encoding element in the fixing position.

3. The process according to claim 1, wherein at least one of the steps a) to d) is carried out at least partly in a pick-and-place machine.

4. The process according to claim 1, wherein the encoding element is a surface-mountable device and the encoding element is fixed in place in or on the optoelectronic module using surface-mounting technology.

5. The process according to claim 1, wherein one holding device is provided which is adapted to fix in place the encoding element, wherein the optoelectronic module comprises a carrier element and the holding device is arranged on or in the carrier element or on or in a plug-in element or plug-in connector attached to the carrier element.

6. The process according to claim 5, wherein the holding device is formed at least in part by a recess in the carrier element, in the plug-in element or in the plug-in connector and wherein the encoding element is arranged in the recess.

7. The process according to claim 1, wherein the optoelectronic module comprises a holding device having a recess which is adapted to fix in place the encoding element, and wherein after fixing the encoding element a heated stamp is pushed onto a surface of the optoelectronic module in a region including the recess, so that material is plastically deformed in a deformation region and the holding device fully encompasses the encoding element.

8. The process according to claim 1, wherein a holding device is provided which is adapted to fix in place the encoding element, and wherein the holding device is adapted to effect an irreversible fixing of the encoding element.

9. The process according to claim 1, wherein the optoelectronic module comprises a holding device having a recess which is adapted to fix in place the encoding element, and wherein a cover element of the holding device is arranged over the recess, so that the encoding element is fixed by a form locking manner on the one hand by lateral inner faces of the recess and on the other hand by the cover element and by a base face of the recess, and in this way the holding device fully encompasses the encoding element.

10. The process according to claim 1, wherein a holding device is provided which is adapted to fix in place the encoding element, said the holding device comprising at least one locking device which is movable between a locking position and a receiving position, wherein in the receiving position the encoding element can be displaced along an insertion direction towards a fixing position inside the holding device and wherein in the locking position the locking device is adapted to effect at least partial fixing of the encoding element in the fixing position.

11. The process according to claim 10, wherein the locking device comprises at least one locking element made of an elastic material which is adapted to allow a displacement of the encoding element along the insertion direction towards the fixing position as a result of its being elastically deformed in consequence of the displacement, and further, once the fixing position of the encoding element has been reached, to assume its original shape and hereby fix the encoding element in place.

12. The process according to claim 11, wherein the locking element is in the form of a tongue which, in the locking position, forms an acute angle of less than 30° with the insertion direction and projects from a lateral inner wall of the holding device.

13. The process according to claim 10, wherein in step d) the encoding element is inserted or pushed into the fixing position along the insertion direction.

14. The process according to claim 1, wherein the encoding element carries information relating to an initial brightness of the optoelectronic module and a resistance value of the encoding element is chosen so that direct or indirect measurement of the resistance value enables conclusions to be drawn as to the initial brightness of the optoelectronic module.

15. A process for the production of an optoelectronic module having the steps of: a) providing an optoelectronic module having at least one semiconductor chip provided for emitting electromagnetic radiation; b) measuring an optical or electronic parameter of the optoelectronic module; c) providing an encoding element in the form of a surface-mountable device having two electrical contact surfaces wherein the encoding element carries information relating to the optical or electronic parameter of the optoelectronic module; and d) fixing the encoding element in place in or on the optoelectronic module, wherein the optoelectronic module has a holding device which comprises a recess and electrical contact elements being arranged on a base face of the recess, wherein in a fixing position, the two electrical contact surfaces of the encoding element lie on the electrical contact elements in the recess.

16. A process for acquiring information provided by the encoding element of the optoelectronic module produced according to claim 15, wherein a control unit for driving the optoelectronic module is provided, and wherein information provided by the encoding element is acquired by the control unit via electrical conductor tracks, said electrical conductor tracks being connected to the two electrical contact surfaces of the encoding element via the electrical contact elements of the holding device.

17. The process according to claim 16, wherein the encoding element carries information relating to an initial brightness of the optoelectronic module and a resistance value of the encoding element is chosen so that direct or indirect measurement of the resistance value enables conclusions to be drawn as to the initial brightness of the optoelectronic module.

Description

[0044] Further advantages, advantageous embodiments and developments will be found in the exemplary embodiments described below in conjunction with Figures, wherein

[0045] FIG. 1 is a schematic view of an optoelectronic module according to the invention in accordance with an exemplary embodiment,

[0046] FIGS. 2A and B show a schematic rear view and front view, respectively, of a plug-in connector which is arranged on the optoelectronic module according to the invention in accordance with the exemplary embodiment,

[0047] FIG. 3 shows a schematic plan view of a holding device arranged in the plug-in connector,

[0048] FIGS. 4A and B are schematic sectional views of the holding device,

[0049] FIG. 5 shows schematically the insertion of an encoding element into the holding device,

[0050] FIGS. 6A and B show schematic sectional views of the holding device with the encoding element inserted,

[0051] FIGS. 7A, B and C show a locking device of the holding device in three different movement positions and a process for the production of an optoelectronic module in accordance with a first exemplary embodiment,

[0052] FIGS. 8A, B, C and D show a process for the production of an optoelectronic module in accordance with a second exemplary embodiment, and

[0053] FIGS. 9A, B and C show a process for the production of an optoelectronic module in accordance with a third exemplary embodiment.

[0054] In the exemplary embodiments and Figures, elements that are identical or similar or have identical action may in each case be denoted by the same reference numerals. The elements illustrated and the relative sizes of the elements to one another should not be regarded as to scale; rather, the size of individual elements, such as, for example, layers, components, devices and regions, may have been exaggerated in the drawings for the purpose of better clarity and/or better understanding; this may relate to individual dimensions or to all dimensions of the elements.

[0055] FIG. 1 shows schematically an optoelectronic module according to the invention, indicated as a whole by reference numeral 100. The module comprises a plurality of semiconductor devices 10 which in operation emit blue light that is converted into white light by conversion elements (not shown in detail). The semiconductor devices 10 are soldered to a ceramic circuit board 11 which is adhesively bonded and attached to a metal core circuit board 30 serving as carrier element. On the metal core circuit board 30 there is further arranged a temperature sensor 33 which is adapted to determine the temperature of the optoelectronic module 100 or, in particular, of the plurality of semiconductor devices 10. It is also possible for each semiconductor device 10 to be assigned one temperature sensor, so that each temperature sensor essentially determines the temperature of the semi-conductor device associated therewith.

[0056] The temperature sensor 33 can be in the form of a thermoelement. Furthermore, the temperature sensor 33 can also be a temperature-dependent resistor which can have a negative temperature coefficient (NTC resistor) or a positive temperature coefficient (PTC resistor). Alternatively, it is also possible for a semiconductor device, for example a transistor or a diode, to be used as temperature sensor.

[0057] There is further soldered to the metal core circuit board 30 a plug-in connector 40 in which electrical conductor tracks 41a, b, c, d, e, f (visible in FIG. 2A) are embedded. The electrical conductor tracks 41a, b, c, d, e, f terminate in a plurality of angular soldering pins 31a, b, c, d, e, f, which are soldered to corresponding soldering surfaces 34a, b, c, d, e, f of the metal core circuit board 30. The soldering surfaces 34c, d, e, f are each part of respective electrical conductor tracks 32c, d, e, f, which are arranged on the metal core circuit board 30 and via which the semiconductor devices 10 and the temperature sensor 33 are each supplied with operating current.

[0058] By means of a complementary connector (not shown), the optoelectronic module 100 is connected via the plug-in connector 40 and via a wiring harness to a control unit (not shown) which provides an operating current for the semiconductor devices 10 and the temperature sensor 33 and evaluates the measured data supplied by the temperature sensor 33.

[0059] In the plug-in connector 40 there is provided a recess 21 inside which a holding device 20 for fixing in place a surface-mountable device is arranged. FIGS. 2A and B show schematic views of the plug-in connector 40 from two different perspectives. The electrical conductor tracks 41a, b, c, d, e, f embedded in the plug-in connector 40 are exposed on one side of the plug-in connectors 40 where they merge into plug-in contacts which are insertable into suitable sockets of the complementary connector (not shown). On the opposite side of the plug-in connector 40 the electrical conductor tracks 41a, b, c, d, e, f are led to the outside and are connected to the angular soldering pins 31a, b, c, d, e, f which are soldered to the soldering surfaces 34a, b, c, d, e, f provided for that purpose on the metal core circuit boards 30. The electrical conductor tracks 41c, d are used to supply electrical power to the temperature sensor 33, and the electrical conductor tracks 41e, f are used to supply electrical power to the semiconductor devices 10. The angular soldering pins 31a, b connected to the electrical conductor tracks 41a, b terminate on soldering surfaces 34a, b, which are not connected to any additional electrical conductor track on the metal core circuit board 30.

[0060] FIG. 3 shows a schematic, perspective view of an upper side of the plug-in connector 40. The holding device 20 provided in the recess 21 comprises two tongues 23a, b made of elastic material, for example of metal or plastics, which serve as locking elements and project from two lateral inner walls 26a, b of the recess 21.

[0061] FIGS. 4A and B show two sectional views of the holding device 20, from which it can be seen that the electrical conductor tracks 41a, b guided through the plug-in connector 40 project into the recess 21 where they form electrical contact elements 22a, b (of which only the electrical contact element 22b is shown in FIGS. 4A and 4B).

[0062] FIG. 5 is a further schematic, perspective view of the plug-in connector 40, showing an insertion direction 24 along which an encoding element 50 in the form of a surface-mountable device is insertable into the holding device 20. The insertion direction 24 runs perpendicular to the surface of the metal core circuit board 30 and parallel to the lateral inner faces 26a, b of the recess 21. The encoding element 50 is more specifically an SMD resistor, the resistance value of which corresponds to a measured brightness of the light emitted by the optoelectronic module 100. The encoding element 50 has two electrical contact surfaces 51a, b which are in electrical contact with the electrical contact elements 22a, b of the holding device 20 once the encoding element 50 has been inserted into the holding device 20.

[0063] FIGS. 6A and B show two schematic, perspective views of the holding device 20 with the encoding element 50 inserted therein. The elastic tongues 23a, b act as locking lugs which allow displacement of the encoding element 50 along the insertion direction, so that the insertion of the encoding element 50 requires the application of only a small amount of force. In a fixing position 25, in which the encoding element 50 is located in FIGS. 6A and 6B, the tongues 23a, b are located in a locking position by means of which the encoding element 50 is irreversibly fixed in place, that is to say the encoding element 50 cannot be removed from the holding device 20 at all or can be removed therefrom only by the application of a substantial amount of force. Along the insertion direction 24, the encoding element is fixed by form lock in the fixing position 25 on the one hand by the elastic tongues 23a, b and on the other hand by the electrical contact elements 22a, b, on which the encoding element 50 is supported by means of its two electrical contact surfaces 51a, b. Perpendicular to the insertion direction 24, the encoding element 50 is fixed by form lock by inner faces 26a, b, c, d of the recess 21. As a result of the form lock fixing of the encoding element 50, the holding device 20 acts additionally as a protective device which encompasses most of the encoding element 50.

[0064] Preferably, the encoding element 50 is an SMD resistor in the form of a parallelepiped. Accordingly, the distances between the lateral inner faces 26a, b, c, d of the recess 21 and the length and the arrangement of the elastic tongues 23a, b are preferably chosen so that they are able to effect form lock fixing of a parallelepiped of such dimensions.

[0065] The encoding element 50 carries information relating to the initial brightness of the optoelectronic module 100, that is to say a brightness which has been determined by a measuring apparatus at a reference current and reference temperature prior to the actual start-up of the optoelectronic module 100. More specifically, the resistance value of the encoding element 50 is chosen so that direct or indirect measurement of the resistance value enables conclusions to be drawn as to the initial brightness of the optoelectronic module 100. Via the electrical conductor tracks 41a, b, which are connected to the two electrical contact surfaces 51a, b of the encoding element 50 via the electrical contact elements 22a, b of the holding device 20, a control unit connected thereto, which serves for driving the optoelectronic module 100, is able to determine the resistance value of the encoding element 50. The electrical conductor tracks 41a, b and the further intermediately connected elements, such as, for example, a complementary connector inserted into the plug-in connector 40 and a wiring harness running between the complementary connector and the control unit, accordingly serve as transmission means via which the information provided by the encoding element 50 can be acquired by the control unit.

[0066] On the basis of the initial brightness of the optoelectronic module 100 and optionally of a measured temperature value determined by the temperature sensor 33, the control unit provides via the electrical conductor tracks 41e, f and 32e, f a suitable operating current with which the semiconductor devices 10 are powered.

[0067] Preferably, resistance values from an e-series are used which are sufficiently distinguishable in terms of ageing and the temperature behaviour of the resistor and are each associated with specific brightness values.

[0068] FIGS. 7A to C show the locking device formed by the elastic tongues 23a, b in three different movement positions. FIG. 7A shows the elastic tongues 23a, b in a locking position in which they form an acute angle of less than 45°, preferably less than 30°, with the insertion direction 24 and project from the two lateral inner walls 26a, b of the recess 21. The encoding element 50 is then displaced along the insertion direction 24 until the fixing position 25 inside the holding device 20 is reached (shown in FIG. 7C).

[0069] During the displacement of the encoding element 50 along the insertion direction 24, the elastic tongues 23a, b yield and are pressed to the side, and are thereby elastically deformed, by the displacement of the encoding element 50. As a result, the elastic tongues 23a, b are moved into a receiving position (shown in FIG. 7B) in which they allow the continued displacement of the encoding element 50 along the insertion direction 24. Once the fixing position 25 has been reached (FIG. 7C), the elastic tongues 23a, b are returned to their original shape under the action of a elastic restoring force and are then located in the locking position again. In this position they fix the encoding element 50 in place in such a way that displacement in a direction opposite to the insertion direction 24 is prevented. On the base face 27 of the recess 21 there are arranged the electrical contact elements 22a, b on which, in the fixing position 25, the encoding element 50 is supported by its two electrical contact surfaces 51a, b.

[0070] A process for the production of an optoelectronic module in accordance with a first exemplary embodiment is described hereinbelow. First of all an optoelectronic module 100 shown in FIG. 1 is provided. Then a brightness of the white light emitted by the optoelectronic module 100 is measured at a reference current and a reference temperature. A suitable encoding element 50 representing the brightness of the optoelectronic module 100 is then selected, is lifted by a vacuum tweezers of a pick-and-place machine and inserted into the holding device 20 shown in FIGS. 7A to C. More specifically, from a plurality of identically constructed SMD resistors which represent different brightness values, a device is selected the resistance value of which best represents the measured brightness of the optoelectronic module 100 and, with the aid of the vacuum tweezers of the pick-and-place machine, is pressed into the holding device 20 of the optoelectronic module 100.

[0071] FIGS. 8A to D illustrate a process for the production of an optoelectronic module in accordance with a second exemplary embodiment. In a first process step, an optoelectronic module is provided which has a recess 21 which, for example, can again be provided in the plug-in connector 40. In contrast to FIGS. 7A to C, in this exemplary embodiment no locking elements in the form of elastic tongues or the like are provided in the recess 21. On the base face 27 of the recess 21, however, there are again arranged electrical contact elements 22a, b. Once the brightness of the optoelectronic module has been measured, a suitable encoding element 50 is inserted into the recess 21 in such a way that the two electrical contact surfaces 51a, b of the encoding element 50 lie on the electrical contact elements 22a, b arranged in the recess 21 (FIG. 8B). A cover element 28 is then arranged over the recess 21, so that the encoding element is fixed by form lock on the one hand by the lateral inner faces 26a, b of the recess and on the other hand by the cover element 28 and the base face 27 (shown in FIGS. 8C and D). As a result, a holding device 20 which fully encompasses the encoding element 50 is provided.

[0072] FIGS. 9A to C illustrate a process for the production of an optoelectronic module 100 in accordance with a third exemplary embodiment. This embodiment differs from the second exemplary embodiment in that no cover element is arranged on the recess 21. Rather, first of all the encoding element 50 is inserted into the fixing position 25 (shown in FIG. 9B). Then, from the outside, a heated stamp 60 is pushed along the insertion direction 24 onto a surface of the optoelectronic module in a region including the recess 21, so that material is plastically deformed in a deformation region 29. As a result, there is again produced in turn a holding device 20 which fully encompasses the encoding element 50.