Stacked optoelectronic -ic device
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-07
- Publication Date
- 2026-03-18
Smart Images
Figure EP2024062661_14112024_PF_FP_ABST
Abstract
Description
[0001] STACKED OPTOELECTRONIC p-IC DEVICE
[0002] The present application claims priority from German patent application DE 10 2023 112 352 . 1 filed on May 10 , 2023 , the disclosure of which is incorporated herein by way for reference in its entirety .
[0003] The present invention concerns an optoelectronic device , a transparent panel comprising at least one of the optoelectronic devices , as well as a method for manufacturing the optoelectronic device .
[0004] BACKGROUND
[0005] Transparent optoelectronic foils , which are foils comprising integrated emitters and / or detectors , become more and more interesting for several applications such as for example laminated glass panels , displays and further intelligent transparent devices . In such optoelectronic foils driver ( s ) are needed for desired functionalities of the foil . The more functionality is desired, the larger the drivers ( pICs ) need to be ( e . g . 250x250pm size ) , which in turn results in an undesired lower transparency of the foil .
[0006] It is an obj ect of the present application to provide an optoelectronic device , a transparent panel comprising at least one of the optoelectronic devices , as well as a method for manufacturing the optoelectronic device , by which a high transparency of the transparent panel can be provided while providing a high functionality at the same time .
[0007] SUMMARY OF THE INVENTION
[0008] This and other obj ects are addressed by the subj ect matter of the independent and subsidiary claims . Features and further aspects of the proposed principles are outlined in the dependent claims .
[0009] The core idea of the present application to reduce the lateral dimensions of the necessary driver per optoelectronic device is to split the driver into at least two portions and stack these at least two portions above of each other . An optoelectronic component comprised by the optoelectronic device is also stacked with these at least two driver portions to further reduce the lateral footprint of the device .
[0010] According to a first aspect an optoelectronic device is provided comprising a first integrated circuit and a second integrated circuit arranged on the first integrated circuit . The first integrated circuit comprises first contact pads for electrically contacting and / or operating the optoelectronic device and second contact pads . The second integrated circuit comprises third contact pads electrically coupled to at least some of the second contact pads of the first contact pad, thus the first and second integrated circuit are electrically coupled to each other . The optoelectronic device further comprises an optoelectronic component arranged on the first or second intergraded circuit , wherein the optoelectronic component is electrically coupled to the first or second intergraded circuit , and in particular to fourth contact pads of the first or second intergraded circuit . The first integrated circuit thereby comprises a first functionality or subfunctionality for operating the optoelectronic component and the second integrated circuit comprises a second functionality or subfunctionality for operating the optoelectronic component .
[0011] The first functionality or sub-functionality can for example be analogue functions for operating the optoelectronic component and the second functionality or sub-functionality can for example be digital functions for operating the optoelectronic component . For example , the first integrated circuit may be an analogue circuit , whereas the second integrated circuit may be a digital circuit . However, the order can also be the otherer way around or both integrated circuits can also be of the same type . The same can apply to further integrated circuits that may be comprised by the optoelectronic device .
[0012] In some aspects , the optoelectronic component is arranged adj acent to the second integrated circuit on the first integrated circuit and is electrically coupled to fourth contact pads of the first integrated circuit . Thus , the first integrated circuit comprises first contact pads for electrically contacting and / or operating the optoelectronic device , second contact pads at least some of which are electrically coupled to the second integrated circuit , as well as fourth contact pads electrically coupled to the optoelectronic component .
[0013] In some aspects , the optoelectronic component is arranged on the second integrated circuit opposite the first integrated circuit electrically coupled to fourth contact pads of the second integrated circuit . Thus , the second integrated circuit comprises third contact pads electrically coupled to at least some of the second contact pads , as well as fourth contact pads electrically coupled to the optoelectronic component .
[0014] In some aspects , the optoelectronic device further comprises at least a third integrated circuit arranged adj acent to the second integrated circuit on the first integrated circuit comprising fifth contact pads electrically coupled to at least some of the second contact pads . The optoelectronic component can in such a case be arranged on the first integrated circuit adj acent to the second and third integrated circuit , or the optoelectronic component can be arranged on the second or the third integrated circuit . The respective integrated circuit then comprises fourth contact pads electrically coupled to the optoelectronic component .
[0015] In some aspects , the optoelectronic device further comprises at least a third integrated circuit arranged between the first and the second integrated circuit comprising fifth contact pads electrically coupled to at least some of the third and / or second contact pads . The optoelectronic component can in such a case be arranged on the first integrated circuit adj acent to the stack of the second and third integrated circuit , or the optoelectronic component can be arranged on top of the stack of the second and third integrated circuit on the second integrated circuit . The respective integrated circuit then comprises fourth contact pads electrically coupled to the optoelectronic component . The third integrated circuit can be electrically connected to both the first and second integrated circuit by means of the same electric contacts , can be electrically connected to both the first and second integrated circuit by means of different electric contacts , or can be connected to only one of the first and second integrated circuit . For example the third integrated circuit can be electrically connected to the first and / or second integrated circuit in a parallel way and / or the third integrated circuit can be electrically connected to the first and / or second integrated circuit in a serial way .
[0016] In some aspects , the optoelectronic component and / or the second integrated circuit and / or the third integrated circuit are arranged on the same side of the first integrated circuit as the first contact pads . This can in particular mean that at least the first integrated circuit does not comprise any contact vias through the material of the first integrated circuit , which makes the first integrated circuit cheaper in production . The same can apply to the second and / or third integrated circuit . In addition, such an arrangement of the optoelectronic component with regard to the first contact pads allows the optoelectronic device to be used as a so called "down" emitter or detector . The light emitting area or light detection area of the optoelectronic component can in such a case for example point in the direction of a carrier substrate the optoelectronic component is arranged on .
[0017] In some aspects , the first integrated circuit and / or the second integrated circuit and / or the third integrated circuit are electrically contactable from only one of its sides . This as aforementioned aspect can for example mean that the first and / or second and / or third integrated circuit does not comprise any contact vias through the material of the respective integrated circuit , which makes the integrated circuit cheaper in production . Electric contacts between the integrated circuits and between the respective integrated circuit and the optoelectronic component can be realized by the two contactable sides facing each other or by means of electric contacts along at least one side surface of the respective element to be electrically coupled . It is however also conceivable that one or more than one of aforementioned elements is electrically contactable from only one of its sides and at least another one of aforementioned elements is electrically contactable from more than one of its sides . In some aspects , the second integrated circuit and / or the third integrated circuit are electrically coupled to the first integrated circuit by means of conductive interconnects along at least one side surface of the respective integrated circuit electrically coupling at least some of the second contact pads with the third and / or fifth contact pads . In this case the second integrated circuit and / or the third integrated circuit can for example be contactable from only one of its sides and an electrically coupling can be achieved by means of for example planar interconnects extending from the second contact pads of the first integrated circuit along at least a side surface of the second and / or third integrated circuit to the third and / or fifth contact pads .
[0018] In some aspects , the optoelectronic component is a light emitting element such as a p-LED . A p-LED is in particular a small light emitting diode (LED ) configured to emit light of a desired wavelength or wavelength range with edge lengths smaller than 200 pm, smaller than 100 pm, smaller than 50 pm, smaller than 25 pm or smaller than 10 pm . For example the p-LED can comprise a rectangular cross section with dimensions of 110 pm x 60 pm. The p-LED can be horizontally contactable meaning that contact pads for electrically contacting the p-LED are arranged on the same side of the p-LED, or can be vertically contactable meaning that contact pads for electrically contacting the p-LED are arranged on opposing sides of the p-LED .
[0019] The optoelectronic component can however also be a sensor or p-sensor configured to detect light of a desired wavelength or wavelength range with edge lengths smaller than 200 pm, smaller than 100 pm, smaller than 50 pm, smaller than 25 pm or smaller than 10 pm . For example the p-sensor can comprise a rectangular cross section with dimensions of 110 pm x 60 pm . The p-sensor can be horizontally contactable meaning that contact pads for electrically contacting the p-sensor are arranged on the same side of the p-sensor, or can be vertically contactable meaning that contact pads for electrically contacting the p-sensor are arranged on opposing sides of the p-sensor . In some aspects , the optoelectronic device comprises a plurality of optoelectronic components arranged on the first or second integrated circuit electrically coupled to fourth contact pads . In case of the optoelectronic device comprising more than one optoelectronic component , at least one optoelectronic component can be a light emitting element and at least one optoelectronic component can be a light detecting element . It can also be conceivable that at least one of the optoelectronic component is arranged on the first integrated circuit and at least one other optoelectronic component is arranged on the second integrated circuit . In such a case both the first and second integrated circuit can comprise fourth contact pads electrically coupled to a respective optoelectronic component .
[0020] According to another aspect a transparent panel such as a transparent display or glazing is provided . The transparent panel comprises at least one optoelectronic device according to some of aforementioned aspects as well as a transparent carrier substrate and a conductive structure arranged on the carrier substrate , wherein the at least one optoelectronic device is arranged on the conductive structure being electrically coupled to the same . The carrier substrate can for example be a polyethylene terephthalate ( PET ) or a glass layer . The carrier substrate can for example comprise a transparency of greater than 80% for light with a wavelength of 530nm when coupling the light from the carrier substrate into air .
[0021] The at least one optoelectronic device can be electrically coupled to the conductive structure by means of for example solder bumps arranged between the at least one optoelectronic device and in particular between the first contact pads od the first integrated circuit of the at least one optoelectronic device and the conductive structure . Such a connection can in addition to the electrical connection provide a certain mechanical connection between the optoelectronic device and the conductive structure . However, the at least one optoelectronic device can also be electrically coupled to the conductive structure by means of for example an electrically conductive adhesive , a nanowire structure embedded in an adhesive , or a plated / printed interconnect on top of an adhesive . The adhesive can in such a case provide a certain mechanical connection between the optoelectronic device and the conductive structure whereas the conductive components within or on top of the adhesive can provide the electrical connection .
[0022] In some aspects , the transparent panel further comprises a transparent cover layer encapsulating the optoelectronic device and the conductive structure on carrier substrate . The transparent cover layer can for example be a layer of polyvinyl butyral ( PVB ) or silicone or parylene .
[0023] In some aspects , the at least one optoelectronic device is configured to emit light through the carrier substrate or detect light emitted trough the carrier substrate onto the optoelectronic component . This can in particular result from the arrangement of the optoelectronic device in relation to the carrier substrate .
[0024] In some aspects , the conductive structure is a mesh, in particular metal mesh, arranged on the carrier substrate . The mesh can in particular be configured to not or not hardly influence the transparency of the transparent panel at least for the eye of a viewer of the transparent panel . The mesh can therefore comprise a coating, in particular a black coating to reduce the reflectance of the material of the mesh which provides a higher transparency at least for the perception of a viewer of the transparent panel . The mesh comprises a plurality of portions electrically isolated from one another, each electrically contacting a first contact pad of an optoelectronic device .
[0025] According to another aspect a method for manufacturing an optoelectronic device is provided . The method comprises the steps :
[0026] Providing a first integrated circuit substrate ;
[0027] Processing the integrated circuit substrate to receive at least a first integrated circuit ;
[0028] Providing first and second contact pads on the at least first integrated circuit ;
[0029] Providing a second integrated circuit on the at least first integrated circuit comprising third contact pads electrically coupled to at least some of the second contact pads ; Providing an optoelectronic component on the first or second intergraded circuit being electrically coupled to the first or second intergraded circuit ; wherein the first integrated circuit comprises a first functionality for operating the optoelectronic component and the second integrated circuit comprises a second functionality for operating the optoelectronic component .
[0030] The optoelectronic device manufactured by such a method is in particular an optoelectronic device according to some of aforementioned aspects .
[0031] In some aspects , the step of providing the second integrated circuit on the at least first integrated circuit comprises providing an adhesive on the at least first integrated circuit and a compression bonding of the second integrated circuit on the at least first integrated circuit such that third contact pads of the second integrated circuit come into electrical and mechanical contact with the respective second contact pads of the first integrated circuit .
[0032] In some aspects , the method further comprises a step of providing a third integrated circuit on the at least first integrated circuit comprising third contact pads electrically coupled to at least some of the second contact pads . The step of providing the second integrated circuit can then for example take place after the step of providing the third integrated circuit , and the second integrated circuit can for example be provided on the third integrated circuit such that the third integrated circuit is arranged between the first and second integrated circuit . The third integrated circuit can however also be provided on the first integrated circuit adj acent to the second integrated circuit .
[0033] In some aspects , the method further comprises a step of back etching the integrated circuit substrate on a side opposite the second integrated circuit and providing a reflective coating on the etched surface . By this an emission of light through the at least first integrated circuit can be prevented, and light emitted in the direction of the first integrated circuit can be back reflected . In some aspects , the method further comprises a step of providing a temporary carrier substrate as well as a release layer on the integrated circuit substrate or the reflective coating on a side opposite the second integrated circuit . By means of the temporary carrier substrate and the release layer , the optoelectronic device can in a subsequent step be transferred to a respective target substrate , such as for example the carrier substrate of the transparent panel according to some aspects of the proposed principle .
[0034] In some aspects , the step of processing the integrated circuit substrate comprises a processing to receive a plurality of first integrated circuits , the step of providing a second integrated circuit on the at least first integrated circuit comprises providing each a second integrated circuit on each of the first integrated circuits , and the step of providing an optoelectronic component comprises providing each an optoelectronic component on a respective first or second intergraded circuit . Hence the method can comprise the manufacturing of several optoelectronic devices at the same time .
[0035] In some aspects , the method further comprises a step of testing the optoelectronic device ( s ) , in particular before separating the optoelectronic devices from each other . The step of testing can for example comprise applying of a voltage / current by means of testing probe ( s ) .
[0036] In some aspects , the method further comprises a step of separating individual optoelectronic devices each comprising a first integrated circuit , a second integrated circuit , optionally a third or further integrated circuit and an optoelectronic component . The separation can for example comprise a step of sawing through the integrated circuit substrate . In particular , the step of separating individual optoelectronic devices can take place after the step of providing the temporary carrier substrate as well as the release layer and the separation / sawing can be done down to the release layer but not trough the release layer and the temporary carrier substrate . Hence the separated optoelectronic devices can still be connected by means of the release layer and the temporary carrier substrate but can individually released from the release layer and the temporary carrier substrate .
[0037] According to another aspect a method for manufacturing a transparent panel comprising at least one optoelectronic device according to some of aforementioned aspects is provided . The method comprises the steps :
[0038] Providing a transparent carrier substrate ;
[0039] Providing a conductive structure on the carrier substrate ; and
[0040] Providing at least one optoelectronic device according to some of aforementioned aspects on the electrical structure such that the at least one optoelectronic device is arranged on the conductive structure being electrically coupled to the same .
[0041] In some aspects , the step of providing the at least one optoelectronic device comprises a laser LIFT process to release the at least one optoelectronic device from a temporary carrier substrate and a release layer .
[0042] In some aspects , the method further comprises a step of coating the carrier substrate , the conductive structure and the at least one optoelectronic device with a transparent protective coating .
[0043] Advantages that can result from such an optoelectronic device / transparent panel can for example be :
[0044] Small footprint with a high functionality;
[0045] High transparency;
[0046] Cheap interconnect processes can be used for both, optoelectronic component and integrated circuits .
[0047] SHORT DESCRIPTION OF THE DRAWINGS
[0048] Further aspects and embodiments in accordance with the proposed principle will become apparent in relation to the various embodiments and examples described in detail in connection with the accompanying drawings in which Figure shows a top view of an optoelectronic device in accordance with some aspects of the proposed principle ;
[0049] Figures 2A and 2B show each a cross section of the optoelectronic device of Fig . 1 integrated into a transparent panel in accordance with some aspects of the proposed principle ;
[0050] Figure shows an exemplary functionality diagram of an optoelectronic device in accordance with some aspects of the proposed principle ;
[0051] Figures 4 and 5 show each a top view of a further embodiment of an optoelectronic device in accordance with some aspects of the proposed principle ;
[0052] Figures 6A and 6B show a top and a side view of a further embodiment of an optoelectronic device in accordance with some aspects of the proposed principle ;
[0053] Figures 7A and 7B show a top and a side view of a further embodiment of an optoelectronic device in accordance with some aspects of the proposed principle ;
[0054] Figures 8A to 8C show top views and a side view of a further embodiment of an optoelectronic device in accordance with some aspects of the proposed principle ;
[0055] Figures 9 to 11 show each a side view of a further embodiment of an optoelectronic device in accordance with some aspects of the proposed principle ;
[0056] Figures 12A to 12G show steps of a method for manufacturing an optoelectronic device in accordance with some aspects of the proposed principle ; Figures 13A and 13B show steps of a method for manufacturing a transparent panel in accordance with some aspects of the proposed principle ;
[0057] Figures 14A to 14E show each a side view of an embodiment of a transparent panel in accordance with some aspects of the proposed principle ; and
[0058] Figure 15 shows a top view of an embodiment of a transparent panel in accordance with some aspects of the proposed principle .
[0059] DETAILED DESCRIPTION
[0060] The following embodiments and examples disclose various aspects and their combinations according to the proposed principle . The embodiments and examples are not always to scale . Likewise , different elements can be displayed enlarged or reduced in size to emphasize individual aspects . It goes without saying that the individual aspects of the embodiments and examples shown in the figures can be combined with each other without further ado , without this contradicting the principle according to the invention . Some aspects show a regular structure or form. It should be noted that in practice slight differences and deviations from the ideal form may occur without , however, contradicting the inventive idea .
[0061] In addition, the individual figures and aspects are not necessarily shown in the correct size , nor do the proportions between individual elements have to be essentially correct . Some aspects are highlighted by showing them enlarged . However , terms such as "above" , "over" , "below" , "under" "larger" , "smaller" and the like are correctly represented with regard to the elements in the figures . So it is possible to deduce such relations between the elements based on the figures .
[0062] Figure 1 shows a top view of a first embodiment of an optoelectronic device 1 in accordance with some aspects of the proposed principle . The optoelectronic device 1 comprises a first integrated circuit 2a, a second integrated circuit 2b, and three optoelectronic components 4a , 4b, 4 c . The first integrated circuit 2a comprises first contact pads 3a for electrically contacting and operating the optoelectronic device 1 , second contact pads 3b , as well as fourth contact pads 3d . The second integrated circuit 2b is arranged on the first integrated circuit 2a and comprises third contact pads 3c facing the second contact pads 3b and being electrically coupled to the second contact pads 3b . The optoelectronic components 4a, 4b, 4 c are arranged on the first intergraded circuit 2a adj acent to the second integrated circuit 2b and are each electrically coupled to the first intergraded circuit 2a by means of the fourth contact pads 3d . For example , the three optoelectronic components 4a, 4b , 4c can be configured to emit red, green and blue light forming a so called RGB-pixel . This is however to be understood as exemplary and the optoelectronic components can also be configured to emit and / or detect light of any other colour as well as any other number of optoelectronic components can be used .
[0063] The first integrated circuit 2a is dimensioned such that on its top surface there is enough space for accommodating the optoelectronic components 4a, 4b , 4 c, the second integrated circuit 2b as well as the first contact pads 3a for electrically contacting and operating the optoelectronic device 1 . Each of the optoelectronic components 4a , 4b, 4c and the second integrated circuit 2b thereby covers only a portion of the top surface of the first integrated circuit 2a . In particular , the first integrated circuit 2a comprises a length 1 and a width b in the pm range . Hence the first integrated circuit 2a can also be called a p-IC .
[0064] The first integrated circuit 2a can for example be configured to provide a first functionality or sub-functionality for operating the optoelectronic components 4 whereas the second integrated circuit 2b can for example be configured to provide a second functionality or subfunctionality for operating the optoelectronic components 4 . Via the first contact pads 3a it can for example be provided an incoming data signal DAT IN and an incoming clock signal CLK IN for programming the optoelectronic components 4 , as well as a first potential VDD and a second potential GND for operating the optoelectronic components 4 . In addition, the data signal and the clock signal can be passed on by means of the first contact pads 3a in form of an outgoing data signal DAT OUT and an outgoing clock signal CLK OUT .
[0065] Figures 2A and 2B each show a cross section through the optoelectronic device 1 when integrated into a transparent panel 10 in accordance with some aspects of the proposed principle . Figure 2A shows a cross section along cutline A-A, whereas Figure 2B shows a cross section along cutline B-B . Thus , Figure 2A shows a cross section through the first integrated circuit 2a and one of the optoelectronic components 4a , whereas Figure 2B shows a cross section through the first integrated circuit 2a and the second integrated circuit 2b .
[0066] The optoelectronic device 1 is arranged on a conductive structure 12 on a transparent carrier substrate 11 with the optoelectronic components 4a, 4b , 4 c, the second integrated circuit 2b as well as the first contact pads 3a facing the carrier substrate 11 . By this an emission of light can be provided through the transparent carrier substrate 11 or light incident on the transparent carrier substrate 11 can be detected by means of the optoelectronic device 1 .
[0067] The optoelectronic device 1 is electrically coupled to the conductive structure 12 by means of solder balls 14 electrically coupling the first contact pads 3a and the conductive structure 12 . On the first integrated circuit 2a an adhesive layer 6 is arranged by means of which the optoelectronic components 4a, 4b, 4 c and the second integrated circuit 2b are fixed to the first integrated circuit 2a .
[0068] The optoelectronic device 1 , the carrier substrate 11 as well as the conductive structure 12 are covered by means of a transparent cover layer 13 , which protects the optoelectronic device 1 from external influences . Together with the transparent cover layer 13 the optoelectronic device 1 , the carrier substrate 11 as well as the conductive structure 12 forms an intelligent transparent panel , which can be used for proj ecting light in form of for example text or images and / or for detecting incident light on the panel . Figure 3 shows an exemplary functionality diagram of an optoelectronic device in accordance with some aspects of the proposed principle . In particular Figure 3 shows the split of different functionalities or sub-functionalities for operating three optoelectronic components R, G, B with regard to the first and second integrated circuit 2a , 2b . R, G, B can in this context for example be understood as each an optoelectronic component configured to emit red, green and blue light . For example the first integrated circuit 2a can be configured to provide all necessary digital circuitry for operating the optoelectronic components 4 , whereas the second integrated circuit 2b can be configured to provide all necessary analogue circuitry for operating the optoelectronic components 4 . The second integrated circuit 2b can for example provide an adj ustable current source for each of the optoelectronic components R, G, B , while the first integrated circuit can for example provide a digital programming of the optoelectronic components R, G, B by means of for example shift registers , counters , comparators and memories .
[0069] Figure 4 shows a further embodiment of an optoelectronic device 1 in accordance to some aspects of the proposed principle . In contrast to the embodiment of Figure 1 , the optoelectronic device 1 comprises only one optoelectronic component 4 arranged on the first integrated circuit 2a . The resulting optoelectronic device 1 can thus be very small comprising its own integrated circuit stack for operation .
[0070] Figure 5 shows a further embodiment of an optoelectronic device 1 in accordance to some aspects of the proposed principle . In addition to the embodiment of Figure 1 , the optoelectronic device 1 comprises a third integrated circuit 2c arranged on the first integrated circuit 2a comprising fifth contact pads 3e facing the first integrated circuit 2a and being electrically coupled to some of the second contact pads 3b . The resulting optoelectronic device 1 can thus provide more functionality due to the larger amount of integrated circuit area .
[0071] Figures 6A and 6B show a top and a side view of a further embodiment of an optoelectronic device 1 in accordance with some aspects of the proposed principle . In contrast to the embodiment of Figure 1 , the optoelectronic components 4 are arranged on the second integrated circuit 2b and not on the first integrated circuit 2a . Therefore , the second integrated circuit 2b comprises fourth contact pads 3d on a side facing away from the first integrated circuit 2a being electrically coupled to the optoelectronic components 4 . The third contact pads 3c of the second integrated circuit 2b are in addition not facing the first integrated circuit 2a but are arranged on the same side as the fourth contact pads 3d . An electric contact between the second and third contact pads is therefore realized by means of conductive interconnects 5 extending from the second to the third contact pads along two opposing side surfaces of the second integrated circuit 2b . The conductive interconnects 5 can for example be metallic redistribution layers ( RDLs ) , metallic planar interconnects or metallic printed interconnects . The resulting optoelectronic device 1 can be smaller but a little bit higher compared to the embodiment shown in Figure 1 .
[0072] In Figure 6B it is indicated how the optoelectronic device 1 can be integrated into a transparent panel , an in particular can be connected to the conductive structure 12 of a transparent panel by means of solder bumps 14 . The orientation of the optoelectronic device 1 can thereby be as already described for figures 2A and 2B .
[0073] Figures 7A and 7B show a top and a side view of a further embodiment of an optoelectronic device 1 in accordance with some aspects of the proposed principle . In addition to the embodiment of Figure 6a and 6B, the optoelectronic device 1 further comprises a third integrated circuit 2 c arranged between the first and second integrated circuit . In this specific embodiment , only two optoelectronic components 4 are arranged on the second integrated circuit 2b , which is however only to be understood as exemplary .
[0074] The third integrated circuit 2c comprises fifth contact pads 3e arranged on a side of the third integrated circuit 2c opposite the first integrated circuit 2a . The fifth contact pads 3e are electrically coupled to the second contact pads as well as to the third contact pads by means of conductive interconnects 5 extending from the second to the fifth and from the fifth to the third contact pads along two opposing side surfaces of the second and the third integrated circuit . To allow a contacting of each a top surface of the first , second and third integrated circuits , the three integrated circuits are arranged in steps , such that the conductive interconnects 5 are able to contact the second, fifth and third contact pads arranged along the respective edge of the respective integrated circuit .
[0075] In Figure 7B it is indicated how the optoelectronic device 1 can be integrated into a transparent panel , an in particular can be connected to the conductive structure 12 of a transparent panel by means of solder bumps 14 . The orientation of the optoelectronic device 1 can thereby be as already described for Figures 2A and 2B .
[0076] The design to Figures 6A to 7B can have the advantage that the first , the second and the optional third integrated circuit can be manufactured without having contact vias through the integrated circuit itself but still provide a contacting on both sides of the second integrated circuit 2b .
[0077] Figures 8A to 8C show top views and a side view of a further embodiment of an optoelectronic device 1 in accordance with some aspects of the proposed principle . Figure 8A shows an optoelectronic device 1 with a first integrated circuit 2a and a second integrated circuit 2b, wherein second contact pads 3a of the first integrated circuit 2a and third contact pads 3c of the second integrated circuit 2b are facing each other and being electronically connected . The first integrated circuit 2a further comprises first contact pads 3a for electrically contacting and operating the optoelectronic device 1 as well as fourth contact pads 3d for electrically contacting optoelectronic components 4 . However , the optoelectronic components 4 are to be arranged on the second integrated circuit 2b and not on the first integrated circuit 2a as shown in Figure 8B . Therefore conductive interconnects 5 are provided extending from the fourth contact pads onto the second integrated circuit 2b to provide contact pads for the optoelectronic components 4 to be arranged on the second integrated circuit 2b . Figure 8A shows the optoelectronic device 1 before arranging the optoelectronic components 4 on the second integrated circuit 2b and Figure 8B shows the optoelectronic device 1 after arranging the optoelectronic components 4 on the second integrated circuit 2b .
[0078] Such a design can have the advantage that the first and the second integrated circuit can be manufactured without having contact vias through the integrated circuit itself but still provide a contacting on both sides of the second integrated circuit 2b .
[0079] Figure 9 shows a side view of a further embodiment of an optoelectronic device 1 in accordance with some aspects of the proposed principle . In this optoelectronic device 1 the first integrated circuit 2a comprises contact vias 15 for guiding the first contact pads 3a to the bottom side of the first integrated circuit 2a opposite the second contact pads 3b . By this the optoelectronic device 1 can be integrated upside down into a transparent panel compared to aforementioned embodiments .
[0080] Figure 10 shows a side view of a further embodiment of an optoelectronic device 1 in accordance with some aspects of the proposed principle . In this optoelectronic device 1 the second integrated circuit 2b comprises contact vias 15 for guiding the fourth contact pads 3d to a side of the first integrated circuit 2a opposite the third contact pads 3c . By this the optoelectronic component ( s ) 4 can be arranged on the second integrated circuit 2b without having conductive interconnects along side surfaces of the second integrated circuit 2b compared to the embodiments of Figures 6A and 6B and Figures 8A to 8C .
[0081] Figure 11 shows a side view of a further embodiment of an optoelectronic device 1 in accordance with some aspects of the proposed principle . In this optoelectronic device 1 the first , second and third integrated circuit 2b comprises contact vias 15 for guiding respective contact pads to an opposing side of the respective integrated circuit . By this the integrated circuits can be stacked and the optoelectronic component ( s ) 4 can be arranged on the second integrated circuit 2b without having conductive interconnects along side surfaces of the second and third integrated circuit compared to the embodiments of Figures 6A and 6B , 7A and 7B and Figures 8A to 8C . Figures 12A to 12G show steps of a method for manufacturing an optoelectronic device 1 in accordance with some aspects of the proposed principle . In a first step , as shown in Figure 12A, an integrated circuit substrate 2 is provided, which is processed to receive first integrated circuit portions 2a . The processing can for example comprise standard CMOS processing technologies . On the integrated circuit substrate 2 and the first integrated circuit portions 2a respectively, first , second and fourth contact pads as well as sixth contact pads 3f are provided . The contact pads can for example be provided by means of standard pad processing technologies and the pads can for example be of gold or gold alloy .
[0082] In a further step , as shown in Figure 12B, an adhesive layer is provided on the first integrated circuit portions 2a by for example an spin on process . Subsequently, as shown in Figure 12C, optoelectronic components 4 , as well as second integrated circuits 2b are then arranged on the first integrated circuit portions 2a on respective contact pads . The optoelectronic components 4 , as well as second integrated circuits 2b can for example be electrically connected to the contact pads by using thermocompression bonding techniques . In addition, excessive material of the adhesive layer 6 is removed by for example O2 plasma etching ( ashing ) .
[0083] The whole structure is then tested in a following step , as shown in Figure 12D by means of a testing probe 21 contacting the sixth contact pad ( s ) 3f and applying a current / voltage to it .
[0084] As shown in Figure 12E , the integrated circuit substrate 2 can be thinned from a surface opposite the optoelectronic components 4 and the second integrated circuits 2b by means of for example a TAIKO process . For better handling, a temporary carrier 22 such as for example a grinding carrier ( e . g . a tape ) can be attached to the side not being thinned . On the resulting back surface , a reflective coating 7 / backside metallisation is then provided, as shown in Figure 12 F, of for example Ti , Pd, Pt , Cu nitrides , Cu oxides , Ni , or Rh or any other black resist or dielectric mirror can be provided on the resulting back surface for light protection of the back surface .
[0085] Then a temporary carrier substrate 8 as well as a release layer is provided on the thinned surface and the temporary carrier 22 is removed . As shown in Figure 12G the integrated circuit substrate 2 is then further processed such that optoelectronic devices 1 are separated each comprising a first integrated circuit 2a, a second integrated circuit 2b and an optoelectronic component 4 . The separation / singulation can for example be performed by means of sawing down until the release layer 9 , indicated by the small arrow .
[0086] Figures 13A and 13B show steps of a method for manufacturing a transparent panel in accordance with some aspects of the proposed principle , which can in particular be subsequent to the steps of Figures 12A to 12G . As shown in Figure 13A a transparent carrier substrate 11 with a conductive structure 12 on the carrier substrate 11 and solder bumps 14 on the conductive structure 12 is provided . Opposite the solder bumps 14 , a temporary carrier substrate 8 with a release layer 9 and optoelectronic devices 1 on top is arranged . The temporary carrier substrate 8 is arranged above the solder bumps 14 such that first contact pads 3a of an optoelectronic device 1 are facing the solder bumps 14 . By means of light L , the optoelectronic device 1 is then released from the release layer 9 and falls onto the solder bumps 14 subsequently being electrically connected to the same . This step can in parallel or serial be repeated until the carrier substrate 11 is equipped with a desired amount of optoelectronic devices 1 .
[0087] As shown in Figure 13B it is then provided a transparent cover layer on the carrier substrate 11 with the conductive structure 12 and the optoelectronic components 4 arranged on the conductive structure 12 . By this the optoelectronic components 4 are encapsulated and protected from external influences .
[0088] Figures 14A to 14E show each a side view of further embodiments of a transparent panel in accordance with some aspects of the proposed principle and in particular further embodiments of an optoelectronic device 1 in accordance with some aspects of the proposed principle .
[0089] The optoelectronic device 1 of Figure 14A is electrically connected to the conductive structure 12 by Cu pillars 20 which as solder bumps are easy to be applied on the conductive structure 12 . The optoelectronic device 1 of Figure 14B on the other hand is electrically connected to the conductive structure 12 by means of conductive nanowires 19 encapsulated in an adhesive 17 providing the necessary mechanical stability between the optoelectronic device 1 and the conductive structure 12 .
[0090] The optoelectronic device 1 of Figure 14C is glued by means of an adhesive 17 to the carrier substrate 11 upside down compared to aforementioned embodiments and is electrically connected to the conductive structure 12 by means of conductive interconnects 18 plated or printed onto the adhesive 17 .
[0091] The optoelectronic devices 1 of Figures 14D and 14E show embodiments using a horizontally contactable optoelectronic component 4 whereas in the embodiment of Figure 14E a vertically contactable optoelectronic component 4 with a respective contacting structure to electrically contact the fourth contact pads 3d is used .
[0092] Figure 15 shows a top view of a further embodiment of a transparent panel 10 in accordance with some aspects of the proposed principle . In the embodiment shown, the conductive structure 12 is in form of a conductive mesh separated into portions 16a, 16b, 16c , 16d, ... each electrically coupled to first contact pads 3a of optoelectronic components of the transparent panel 1 . Such a mesh structure can be desired, as it can provide a certain transparency while providing enough conductive cross section to still be able to transmit a necessary current to the optoelectronic devices 1 . The optoelectronic devices 1 can for example be arranged in an array like pattern on the carrier substrate 11 in rows and columns with a distance d between each other relating to a desired pixel distance of the later application of the transparent panel 10 . LIST OF REFERENCES
[0093] 1 optoelectronic device
[0094] 2 integrated circuit substrate 2a, 2b, 2 c integrated circuit
[0095] 3a, 3b, 3c, 3d, 3e contact pad
[0096] 4 , 4a , 4b , 4c optoelectronic component
[0097] 5 conductive interconnect
[0098] 6 adhesive layer 7 reflective coating
[0099] 8 temporary carrier substrate
[0100] 9 release layer
[0101] 10 transparent panel
[0102] 11 carrier substrate 12 conductive structure
[0103] 13 cover layer
[0104] 14 solder bump
[0105] 15 contact via
[0106] 16a , 16b, 16c , ... portions of conductive structure 17 adhesive
[0107] 18 conductive interconnect
[0108] 19 nanowire structure
[0109] 20 conductive pillar
[0110] 21 testing probe 22 temporary carrier
[0111] 1 length b width d distance L light
Claims
CLAIMS1. Optoelectronic device (1) comprising: a first integrated circuit (2a) comprising first contact pads (3a) for electrically contacting and / or operating the optoelectronic device (1) and second contact pads (3b) ; a second integrated circuit (2b) arranged on the first integrated circuit (2a) comprising at least third contact pads (3c) electrically coupled to at least some of the second contact pads ( 3b ) ; and an optoelectronic component (4) arranged on the first or second integrated circuit (2a, 2b) and being electrically coupled to the first or second integrated circuit (2a, 2b) ; wherein the first integrated circuit (2a) comprises a first functionality for operating the optoelectronic component (4) and the second integrated circuit (2b) comprises a second functionality for operating the optoelectronic component (4) .
2. Optoelectronic device according to claim 1, wherein the optoelectronic component (4) is arranged adjacent to the second integrated circuit (2b) on the first integrated circuit (2a) electrically coupled to fourth contact pads (3d) of the first integrated circuit (2a) .
3. Optoelectronic device according to claim 1, wherein the optoelectronic component (4) is arranged on the second integrated circuit (2b) opposite the first integrated circuit (2a) electrically coupled to fourth contact pads (3d) of the second integrated circuit (2b) .
4. Optoelectronic device according to any one of claims 1 to 3, wherein the optoelectronic device (1) further comprises at least a third integrated circuit (2c) arranged adjacent to the second integrated circuit (2b) on the first integrated circuit (2a) comprising fifth contact pads (3e) electrically coupled to at least some of the second contact pads (3b) .
5. Optoelectronic device according to any one of claims 1 to 3, wherein the optoelectronic device (1) further comprises at least a third integrated circuit (2c) arranged between the first and the second integrated circuit (2a, 2b) comprising fifth contact pads (3e) electrically coupled to at least some of the third and / or second contact pads (3c, 3b) .
6. Optoelectronic device according to any one of claims 1 to 5 , wherein the optoelectronic component (4) and / or the second integrated circuit (2b) and / or the third integrated circuit (2c) are arranged on the same side of the first integrated circuit (2a) as the first contact pads (3a) .
7. Optoelectronic device according to any one of claims 1 to 6, wherein the first integrated circuit (2a) and / or the second integrated circuit (2b) and / or the third integrated circuit (2c) are electrically contactable from only one of its sides.
8. Optoelectronic device according to any one of claims 1 to 7 , wherein the second integrated circuit (2b) and / or the third integrated circuit (2c) are electrically coupled to the first integrated circuit (2a) by means of conductive interconnects (5) along at least one side surface of the respective integrated circuit electrically coupling at least some of the second contact pads (3b) with the third and / or fifth contact pads (3c, 3e) .
9. Optoelectronic device according to any one of claims 1 to 8 , wherein the optoelectronic component (4) is a p-LED.
10. Optoelectronic device according to any one of claims 1 to 9, comprising a plurality of optoelectronic components (4a, 4b, 4c) arranged on the first or second integrated circuit (2a, 2b) electrically coupled to fourth contact pads (3d) .
11. Transparent panel (10) comprising at least one optoelectronic device(1) according to any one of claims 1 to 10, as well as a transparent carrier substrate (11) and a conductive structure (12) arranged on the carrier substrate (11) , wherein the at least one optoelectronicdevice (1) is arranged on the conductive structure (12) being electrically coupled to the same.
12. Transparent panel according to claim 11, further comprising a transparent cover layer (13) encapsulating the optoelectronic device (1) and the conductive structure (12) on carrier substrate (ID •13. Transparent panel according to claim 11 or 12, wherein the at least one optoelectronic device (1) is configured to emit light through the carrier substrate (11) .
14. Transparent panel according to any one of claims 11 to 13, wherein the conductive structure (12) is a metal mesh arranged on the carrier substrate (11) , the metal mesh comprising a plurality of portions (16a, 16b, 16c, ...) electrically isolated from one another, each electrically contacting a first contact pad (3a) of the at least one optoelectronic device (1) .
15. Method for manufacturing an optoelectronic device (1) , comprising the steps : Providing a first integrated circuit substrate (2) ;Processing the integrated circuit substrate (2) to receive at least a first integrated circuit (2a) ;Providing first and second contact pads (3a, 3b) on the at least first integrated circuit (2a) ;Providing a second integrated circuit (2b) on the at least first integrated circuit (2a) comprising third contact pads (3c) electrically coupled to at least some of the second contact pads (3b) ;Providing an optoelectronic component (4) on the first or second intergraded circuit (2a, 2b) being electrically coupled to the first or second intergraded circuit (2a, 2b) ; wherein the first integrated circuit (2a) comprises a first functionality for operating the optoelectronic component (4) and the second integrated circuit (2b) comprises a second functionality for operating the optoelectronic component (4) .
16. Method according to claim 15, wherein the step of providing the second integrated circuit (2b) on the at least first integrated circuit (2a) comprises providing an adhesive (6) on the at least first integrated circuit (2a) and a compression bonding of the second integrated circuit (2b) on the at least first integrated circuit ( 2a ) .
17. Method according to claim 15 or 16, further comprising a step of back etching the integrated circuit substrate (2) on a side opposite the second integrated circuit (2b) and providing a reflective coating (7) on the etched surface.
18. Method according to any one of claims 15 to 17, further comprising a step of providing a temporary carrier substrate (8) as well as a release layer (9) on the integrated circuit substrate (2) or the reflective coating (7) on a side opposite the second integrated circuit ( 2b ) .
19. Method according to any one of claims 15 to 18, wherein the step of processing the integrated circuit substrate comprises processing to receive a plurality of first integrated circuits (2a) ; the step of providing a second integrated circuit (2b) on the at least first integrated circuit (2a) comprises providing each a second integrated circuit (2b) on each of the first integrated circuits (2a) ; and the step of providing an optoelectronic component (4) comprises providing each an optoelectronic component (4) on a respective first or second intergraded circuit (2a, 2b) .
20. Method according to claim 19, further comprising a step of separating individual optoelectronic devices (1) each comprising a first integrated circuit (2a) , a second integrated circuit (2b) and an optoelectronic component (4) .