HK1116316A - Supporting substrate for electronic components - Google Patents

Description

The invention relates to a carrier substrate for electronic components, in particular for luminaires, applied to a surface of the carrier substrate, with a transparent substrate and a conductive layer applied to the transparent substrate, and an electronic component with such a carrier substrate and a method for the manufacture of such an electronic component.

LEDs are suitable for a wide range of applications in lighting technology. LED modules include a wide range of LEDs on a carrier substrate. The LEDs placed on the carrier substrate form an indicator unit, which can be used for example to display target locations in a bus. Such an indicator matrix has been known from DE-A-19729469. In the display device according to DE-A-19729469, the LEDs are placed on a transparent film, with the film enveloping the conductors for the supply of light sources.

Preferably, the conductors are arranged in matrix form according to DE-A-19729469.

The individual LEDs on the conductive paths shall be connected by conductive adhesive.

The disadvantage of the display device according to DE-A-19729469 is that the wires applied to the transparent substrate are opaque.

The lighting device with LEDs is known from EP-A-0900971, which consists of a large number of LEDs mounted on the surface of a glass plate. The LEDs are electrically connected to conductors mounted on the glass plate, which are formed as a thin and invisible layer. The conductors and their connections are mounted on the same surface of the glass plate on which the LEDs are also located.

According to EP-A-0900971, the conductors are applied to the glass plate by evaporation of metal, using a masking method prior to evaporation.

The disadvantage of the lighting device according to EP-A-0900971 is that the conductors are already structured during the evaporation process.

Further disadvantages of the systems according to the state of the art were that they did not allow soldering on transparent conductive tracks and did not allow three dimensional shaping, since the conductive layers would be folded during shaping processes such as bending.

The purpose of the invention is to specify a carrier substrate for electronic components, in particular for LEDs or LED modules, comprising several LEDs, which ensures the required transparency, is very cost-effective to manufacture and avoids the high production costs of the systems in accordance with the state of the art.

According to the invention, this task is solved by a carrier substrate, in which the conductive layer applied to the transparent substrate in the visible wavelength range is transparent or quasi-transparent and can be structured as desired.

The application of this layer to the transparent substrate is preferably by chemical vapor deposition (CVD) or physical vapor deposition (PVD), immersion coating, chemical or electrochemical coating.

The use of the spray pyrolysis method is particularly cost-effective, with ZnOx:F being the preferred coating material. If particularly high optical properties are to be achieved, the preferred method is spraying.

In contrast to the state of the art, the above-mentioned ordering methods allow the production of systems with any three-dimensional shape, first by bringing the substrate into the desired three-dimensional shape and then by applying the conductive layer.

Alternatively, the conductive layer may consist of a vaporized or sputtered metal such as Al, Ag, Au, Ni or Cr, which is usually quasi-transparent.

For the purposes of this application, transparent layers or glasses are defined as layers or glasses with a transmission > 90% in the visible wavelength range.

In order to obtain particularly low reflectivity systems, a further development of the invention provides for the application of a special reflective layer to the conductive layer, for example a TiO2 , SiO2 or a mixture layer of TixSi1-xO2.

According to the invention, the conductive layer of metal oxide or metal can be structured not only in matrix form, as in the state of the art, but also in any way. This makes it possible to apply complete structures as on single-layer PCBs (so-called printed circuit boards). This in turn allows to apply complete electronic circuitry to one and the same substrate. The structuring of the conductive layer can be done after application by specifically breaking the layer, for example by means of a laser that is heated locally during the coating and evaporates it. When using a laser to complete the structures in a surface-mounted conductive layer, it is practical if the layer of the laser surface area is in the area of the glass substrate.

Alternatively, a layer with a surface area of less than 1 m2 can be structured by lithography and etching.

However, a structuring is also conceivable in which the conductors are already applied in the specified structure during coating, for example when evaporating using mask techniques.

In order to attach the light-emitting diodes or other electrical components to the supporting substrates, so-called pads may be applied to the conductive layer in a preferred design of the invention. Such pads include a conductive paste or coating, such as silver lead or silver lead coating paste. The application of the individual pads may be by screen printing or stamp printing and then incineration, whereby such a process in the case of glasses as transparent substrates can be used simultaneously to pre-clamp the glass. One advantage of the type of conductor manufactured is that particularly solid glasses can be preserved for a long time without further further treatment. One advantage of this method is that the application of a pad is only possible by using a transparent substrate, which is stable against the heat, but which is not exposed to any further heat, and is made more stable by a combination of various chemicals, such as transparent adhesive and a transparent adhesive.

To connect the components or LEDs to the conductive layer of the carrier substrate via the connecting points, the carrier substrate can be fitted with LEDs according to standard electronics industry methods, for example by applying solder paste to the individual connecting points or connecting pads by printing on a template, after which the LEDs are applied to the carrier plate.

The LEDs are then transferred to a reflow oven, or the LEDs can be sent through a wave soldering bath.

However, the invention also allows the application of a conductive adhesive to the carrier substrate by means of sieve or stamping, so that the luminaires or electrical components can be applied directly to the carrier substrate.

The special advantage of the present invention is its free structurability, which enables the application on the supporting substrate not only of luminaires, e.g. light-emitting diodes, as is the case at present, but also of other electrical or electronic components, covering all known electrical and electronic components, e.g. discrete semiconductors, passive and active components, resistors, capacitors, coils, etc.

For example, it is then possible to apply all the control electronics to the carrier substrate in addition to the LEDs.

In a particularly preferred embodiment, not only individual electrical or electronic components, such as coils or capacitors, are applied to the supporting substrate, but additional boards or hybrid circuits with independent integrated circuits, which may include, for example, a power source or power control.

In the design of an electronic component, in particular a LED module, a preferred design is to protect the luminaires by a second transparent substrate, which is then placed between the transparent carrier substrate and the other transparent substrate, thus providing additional protection of the light sources from environmental influences such as moisture and mechanical abrasion.

A particularly favourable embodiment is that the additional transparent substrate is also provided with a conductive transparent layer, which allows the non-enclosed LEDs to be directly contacted between two conductive substrates.

The transparent substrate can be both a glass and a plastic substrate. It is particularly preferred if the glass substrate is hardened and pre-tensioned.

A particularly preferred embodiment is to connect and contact several supporting substrates with luminaires, e.g. light-emitting diodes, which allows supporting substrates of any shape.

In addition to the carrier substrate for an electronic component, in particular for lighting devices such as LEDs, the invention also provides such an electronic component and a method for the manufacture of such a component.

The application of the supporting substrate of the invention, in particular of an LED module with a similar supporting substrate, is suitable for all applications where lighting, signalling, information or decorative effects are to be achieved. It is particularly desirable to use such LED modules in furniture and window lamps, for the display of lettering, symbols or graphics, for interior or exterior lighting and for escape lighting. A particularly desirable application of such LED modules is in the automotive field, for example as a third brake light on a vehicle that is integrated directly into the tail light.

The LED modules of the invention can also be used in so-called composite systems which include a supporting substrate, for example a resistive touch panel on which the LEDs are mounted.

The invention is further explained by the drawings which show: Figure 1a - 2d.The typical process for producing an LED module according to the invention.Figure 3a - LED module with a further electrical component.Figure 4a - LED module with a split hybrid circuit.Figure 5 - two LED modules of different structure.Figures 6 - 7the connection of LED modules for two-dimensional or three-dimensional geometries.

In Figure 1 a carrier substrate according to the invention is shown with a conductive layer applied to the carrier substrate, which in turn is structured in such a way that on the transparent carrier substrate 1 a circular conductor 3 with connecting conductor 5 ,7 is formed. On the circular conductor 3 individual connecting points 9 are arranged. The connecting points 9 are used to connect the individual luminaires, e.g. the light-emitting diodes 4 conductively to the conductor and thus to ensure the energy supply of the same. Preferably the carrier substrate is a calcium-sodium glass.

Figures 2a to 2d illustrate a process according to the invention for the manufacture of an electronic component, in particular an LED module, whereby the transparent carrier substrate is first coated with a conductive layer of 1 m3 in the surface, for example in the sol gel process.

The structure is then produced, for example by a laser, which heats and evaporates the coating locally, as shown in Figure 2b. The carrier substrates which are structured with a laser preferably include a conductive layer which has a high absorption in the laser wavelength range of the laser used and a substrate which is transmissible at this wavelength.

The characteristics of the individual sections of the substrate are shown in Figure 2b with the reference numbers 11.1 to 11.3. Following the structuring in Figure 2b, individual connecting points, called connecting pads 9, are applied in sections 13.1 to 13.4. The connecting pads 9 comprise a conductive paste or coating, such as silver lead or silver paste, which is applied to the conductive substrate by means of a sieve or stamping press and then fired.

After the contacts have been applied in the different areas 13.1 to 13.4, they are fitted with a standard process, as shown in Figure 2d, for example by applying solder paste to the connecting pads 9, for example by printing on a template. The light-emitting diodes (LEDs) 4 are then applied to the support plate, using a chipbonder which can attach the light-emitting diodes 4 to the support material before the soldering process. After the individual LEDs are attached, the support substrate 1 with the light-emitting diodes attached to it is sent through a reflow oven or a wave bath.

An embodiment of the invention is a glass substrate, typically a soda-lime glass, coated with a fluorinated zinc oxide. The coating shall be applied as follows: A glass of sodium calcium as a transparent substrate is heated to 500°C. The glass is then sprayed with monobutyltin chloride and hydrochloric acid in ethanol, the spray solution having the following composition: Other

Monobutylzinnchlorid	70%
Ethanol	< 30%
Flußsäure	0,4%

Other After spraying, the lime-nitroglass shall be covered with a transparent, fluoro-doped zinc oxide layer.

The coating is then separated with a laser. A silk-based paste, e.g. Cerdec SP 1248, is applied by sieve printing using a rake. The paste is dried in a blast furnace at 140°C for 2 min. and then pre-fired and pre-tensioned by a pre-tensioning system at about 700°C for a soda-lime glass. Commercial solder paste is then applied by stencil printing and filled with light-emitting diodes, e.g. NSCW 100 light-emitting diodes from Fa. Nichia.

In Figure 3 an embodiment of the invention is shown in which a transparent carrier substrate 1 was mounted on the carrier substrate 13.1, 13.2, 13.3, luminous diodes 4 in different ranges by the method described in Figure 2a - 2d. In addition to the luminous diodes 4, the carrier substrate also contains other electronic components, e.g. resistors 17, a semiconductor diode 19 and a transistor 21. Instead of individual components, as shown in Figure 4, in addition to the luminous diodes 4, entire electronic circuit boards can also be mounted on the carrier stratum according to the invention. Goods modules as in the previous figures are also mounted in Figure 4 with the same three-digit LED reference source. The different electronic circuit, e.g. the LED 102.1 or 112.2, is mounted on two LEDs of different voltages and a different voltage.

The geometrically different LED modules 100, 110 can be connected in a flat configuration to a LED module of any two-dimensional geometric shape as shown in Figure 6 and to three-dimensional structures as shown in Figure 7.

The invention specifies for the first time a supporting substrate, the conductive layer of which, unlike the state of the art, is completely transparent and not opaque. In particular, the method of the invention allows the glasses to be pre-tensioned simultaneously in a single process step during the combustion of the connecting point or soldering pad. The free structurability of fully coated glasses makes it possible to easily integrate other electronic components on the supporting substrate of the LED module, such as the controller geometry. The structuring can be achieved independently of the coating with a conductive layer. The insertion of a soldering iron in a wide range of materials makes it possible to create a realistic composition on the supporting substrate of the LED module, which can be printed on any transparent surface.

The present invention covers the aspects set out in the following sentences which form part of the description but are not claims in accordance with the Board of Appeal's decision J15/88:

The following sentences:

1. a supporting substrate for electronic components, in particular luminaires, which is applied to a surface of the supporting substrate with 1.1 a transparent substrate (1) characterised by1.3 the conductive layer being transparent or quasi-transparent in the visible wavelength range and capable of any structural configuration.2. carrier substrate as defined in sentence 1, characterised by the conductive layer containing a metal oxide.3. carrier substrate as defined in sentence 2, characterised by the metal oxide containing one or more of the following metal oxides: InOx:SnSnOx:FSnOx:SbZnOx:GaZnOx:BZnOx:FZnOx:AlAg/TiOx4. Carrier substrate as defined in sentence 3, characterised by the conductive layer being removed by one of the following processes: The test chemical is a sol-gel process. is applied to the transparent substrate (1).5. Carrier substrate in accordance with one of the phrases 1 to 2,"Technology" according to the General Technology Note for the "development" or "production" of "materials" specified in 2B001.b. Al, Ag, Au, Ni, Crumfatt.7. Carrier substrate in one of the sentences 5 to 6, characterised by the metal being evaporated or sprayed.8. Carrier substrate in one of the sentences 1 to 7, characterised by the transparent substrate (1) being a glass or plastic substrate.9. Carrier substrate in one of the sentences 8, characterised by the glass substrate being hardened and/or pre-tensioned.10. Carrier substrate in one of the sentences 8 to 9, characterised by the glass or plastic substrate having a free surface.11. Carrier substrate in one of the sentences 8 to 10,characterised by the glass or plastic substrate being printed with a decorative print.12 Carrier substrate, as defined in any of the phrases 1 to 11, characterised by the layer being structured by one or more of the following processes: Structuring of the conductive layer applied to the supporting plate by laser by heating and evaporation Structuring by lithography and etching of the conductive layer applied to the supporting plate by surface-based structure Structuring by mask technique, where the conductive layer is applied by a pre-determined mask.13.Substrate of the supporting layer, as defined in one of the sentences 1 to 12, characterised by the formation of the conductive layer in such a way that, after application of connecting points, components made of conductive paste or lacquer can be soldered onto the supporting system.14. a supporting substrate as defined in one of the sentences 1 to 13 by having any three-dimensional shape.15. an electronic component, in particular an LED chip, as defined by having a supporting substrate for the component as defined in one of the sentences 1 to 14.16. an electrical component as defined in sentence 15 by having a complete conductive paste or coating applied to the conductive layer at the connecting points (9) to connect individual components, in particular individual light-emitting diodes (4) and then burned.17. an electrical component as defined in sentence 16 by having the individual components welded to the connecting points (9) and connected to the conductive layer of the electrical component according to sentence 15.18.'Electrical component' means an electrical component specified in any of the following phrases 15 to 18: Discrete light-emitting diodes passive and active semiconductor main groupsIC's resistorsCondensator coils20. component in accordance with one of the sentences 15 to 19, characterised by the fact that the component includes another transparent substrate.21. component in accordance with sentence 20, characterised by the fact that the additional transparent substrate is arranged above the components mounted on the carrier substrate, so that the components are protected between the carrier substrate and the further transparent substrate.22. component in accordance with sentence 20 or 21,characterised by the addition of a transparent substrate to a conductive transparent or quasi-transparent layer or film.23. component as defined in one of the phrases 15 to 22 characterised by the addition of multiple supporting substrates with electrical or electronic components.24. process for the manufacture of an electronic component with a supporting substrate as defined in one of the phrases 1 to 14, including the following steps: 24.1 a transparent or quasi-transparent conductive layer is either structured or applied to at least one transparent substrate by a given mask;24.2 in the case of a full surface application, the conductive layer is structured after application;24.3 on the structured conductive layer, connecting points or isotropically conductive adhesives are applied to connect the electrical components to the conductive layer;24.4 in the case of connectors, the electrical assemblies are connected to them by means of soldering connections.25. the procedure described in sentence 24 is characterised by the substrate being shaped in any three-dimensional manner, in particular by bending, before the transparent or quasi-transparent layer is applied.26. the procedure described in sentence 24 or 25 is characterised by the application of the full surface by CVD or PVD processes, in particular by spray pyrolysis, sputtering or the sol-gel technique.27. the procedure described in one of the sentences 24 to 26 is characterised by the structuring of the full surface layers by interruption of this layer by laser or quasi-transparent lithography and then by a targeted etching process.28. the procedure described in sentences 24 to 27 is characterised by the use of a laser or laser etching and a targeted etching process.28.characterised by the application of the connecting points of a conductive paste or paint by means of screen printing or stencil printing and then burning into the transparent substrate, the transparent substrate being pre-tensioned.

Claims (14)

1. A process for the manufacture of a component with lighting, including the following steps: Other

   - a transparent or quasi-transparent conductive layer, comprising zinc oxide, is applied to a transparent substrate (1);

   - the transparent or quasi-transparent conductive layer is structured;

   - at least one light source is applied to the structured transparent or quasi-transparent layer.
2. The method described in claim 1 is characterised by the luminaires being LEDs and the LEDs (4, 102.1-102.3, 112.1-112.4) being connected to the conductive layer of the carrier substrate (1) via connecting points.
3. The method described in claims 1 to 2 is characterised by the application of light-emitting diodes (4, 102.1 to 102.3, 112.1 to 112.4) to the supporting substrate (1) using standard electronics-industry methods.
4. A process according to any of the following claims 1 to 3: the structuring of the transparent or quasi-transparent conductive layer is achieved by the targeted interruption of this layer by a laser.
5. The method described in claims 1 to 4 is characterised by the application of the transparent or quasi-transparent conductive layer by spraying the transparent substrate (1).
6. The method described in claim 5 is characterised by heating the transparent or quasi-transparent substrate to 500 °C and spraying it with monobutyltin chloride and fluoric acid in ethanol to produce a fluoro-dotted zinc oxide layer.
7. Process according to one of claims 1 to 6 characterised by the transparent substrate being glass, in particular tempered and/or pre-stressed glass, preferably soda-lime glass.
8. A process according to one of the claims 1 to 7 characterised by placing another transparent substrate on top of the transparent or quasi-transparent substrate (1) with applied light sources (4, 102.1 to 102.3, 112.1 to 112.4).
9. a height of not more than 300 mm Other

   - a transparent substrate with a transparent or quasi-transparent conductive layer and luminaires placed on the transparent or quasi-transparent conductive layer,

   - the transparent or quasi-transparent conductive layer of zinc oxide.
10. The component described in claim 9 is characterised by the presence of a zinc oxide doped with zinc oxide selected from Other

    - SnOx:F

    - SnOx:Sb

    Other The Commission is
11. A component according to one of claims 9 to 10 characterised by the transparent substrate being a glass, in particular a tempered and/or pre-stressed glass, preferably a lime-sodium glass.
12. A component according to one of the claims 9 to 11 characterised by the fact that the light source is a light-emitting diode.
13. A component according to one of the claims 9 to 12 characterised by the conductive layer having a structure which is inserted into the conductive layer by means of a laser.
14. A component according to one of the claims 9 to 13 characterised by the addition of a transparent substrate on top of the transparent or quasi-transparent substrate.