TWI650882B - Flexible light source structure and method for manufacturing same - Google Patents

Abstract

The invention relates to a flexible ultra-thin illuminant structure, comprising: a flexible dielectric layer, a conductive circuit layer formed on a surface of the flexible dielectric layer, a light-emitting chip formed on a surface of the conductive circuit layer, and covering the An encapsulation layer of the light-emitting chip, the surface of the conductive circuit layer further having a circuit component, the circuit component comprising a control element for controlling illumination of the light-emitting chip and/or a switching element for driving the light-emitting chip, The encapsulation layer covers the luminescent wafer, the circuit component, and a gap between the circuit component and the luminescent wafer. The invention also relates to a method of fabricating a flexible ultra-thin illuminant structure. The flexible ultra-thin illuminator structure formed by the method can meet the requirements of thinning and flexibility, and can be used in an indicator box, an illumination board, a backlight module, an advertising lamp board and the like.

Description

Flexible ultra-thin illuminator structure and manufacturing method thereof

The present invention relates to the field of display technologies, and in particular, to a flexible ultra-thin illuminator structure that can be used in a backlight module.

With the advancement of optoelectronic technology, the application of light-emitting diode light sources has become more and more extensive, such as indicator boxes, lighting panels, backlight modules, advertising panels and other applications. Regardless of the application, it revolutionizes all types of lighting and display products, and subverts the stereotypes that are currently recognized. Most product applications have developed light-emitting diode sources toward ultra-thin surface light source technology.

As far as the related art is concerned, there is a partial loss in the side-projection light source module or the direct-lit light source module, for example, it is not flexible. Therefore, it is necessary to provide a flexible light source module.

In view of the above, it is necessary to provide a flexible ultra-thin illuminator structure that can solve the above technical problems.

A flexible ultra-thin illuminant structure comprising: a flexible dielectric layer, a conductive circuit layer formed on a surface of the flexible dielectric layer, a light-emitting chip formed on a surface of the conductive circuit layer, and an illuminating wafer covering the luminescent wafer An encapsulation layer, a surface of the conductive circuit layer further formed with circuit elements, the circuit element comprising a control element for controlling illumination of the illumination wafer and/or a switching element for driving the illumination wafer, the encapsulation layer Covering the light-emitting chip, the circuit component, and filling a gap between the circuit component and the light-emitting chip.

In a preferred embodiment, the thickness of the encapsulation layer is between 1 micrometer and 500 micrometers, and the thermal expansion coefficient of the encapsulation layer is consistent with the thermal expansion coefficient of the dielectric layer.

In a preferred embodiment, the flexible dielectric layer is a transparent polymer film, and the flexible dielectric layer has a thickness of 5 micrometers to 50 micrometers.

The invention relates to a method for manufacturing a flexible ultra-thin illuminant structure.

A method for fabricating a flexible ultra-thin illuminant structure, comprising the steps of: providing a support substrate, forming a flexible dielectric layer on a surface of the support substrate; forming a conductive circuit layer on a surface of the flexible dielectric layer; a surface of the conductive circuit layer is provided with a plurality of light-emitting wafers; an encapsulation layer is formed on a surface of the light-emitting chip, the encapsulation layer covers a gap between the light-emitting chip and the filling light-emitting chip; and the flexible medium is The support substrate on the bottom surface of the electrical layer is removed to obtain a flexible ultra-thin illuminant structure.

In a preferred embodiment, the step of forming a circuit component on the surface of the conductive wiring layer using a low temperature polysilicon technology is further included after the formation of the conductive wiring layer.

In a preferred embodiment, the conductive circuit layer is formed on the flexible dielectric layer by sputtering, vapor deposition or electroplating, and the conductive circuit layer has a thickness of 5 to 50 micrometers.

In a preferred embodiment, the support substrate is removed by bending, etching, laser cutting or grinding.

In a preferred embodiment, the flexible dielectric layer is a transparent polymer film, and the flexible dielectric layer has a thickness of 5 micrometers to 50 micrometers.

In a preferred embodiment, the thermal expansion coefficient of the encapsulation layer is consistent with the thermal expansion coefficient of the dielectric layer, and the thickness of the encapsulation layer is between 1 micrometer and 500 micrometers.

In a preferred embodiment, the encapsulating layer is one of polyethylene terephthalate, epoxy resin, and decane.

Compared with the prior art, the manufacturing method of the flexible ultra-thin illuminant structure provided by the present invention and the flexible ultra-thin illuminant structure formed thereby can meet the requirements of thinning and flexibility, and can realize Double-sided light can be used in indicator boxes, lighting panels, backlight modules, advertising panels and other devices.

100‧‧‧Flexible ultra-thin illuminator structure

10‧‧‧Support substrate

20‧‧‧Flexible dielectric layer

30‧‧‧ Conductive circuit layer

32‧‧‧ Circuit components

40‧‧‧Lighting chip

50‧‧‧Encapsulation layer

60‧‧‧Laser light source

12‧‧‧ upper surface

14‧‧‧ Lower surface

1 is a flow chart showing the fabrication of a flexible ultra-thin illuminator structure provided by the present invention.

2 is a cross-sectional view showing a support substrate and a flexible dielectric layer formed on the support substrate.

Figure 3 is a cross-sectional view showing the formation of a conductive wiring layer on the basis of Fig. 2.

4 is a cross-sectional view showing the formation of a light-emitting wafer on the basis of FIG.

Figure 5 is a cross-sectional view of a layer of encapsulation laminated on the basis of Figure 4.

Figure 6 is a cross-sectional view showing the support substrate removed on the basis of Figure 5.

Figure 7 is a cross-sectional view showing the structure of the finally obtained flexible ultra-thin illuminator.

The flexible ultra-thin illuminant structure 100 provided by the present invention and the flexible ultra-thin illuminant structure 100 thus obtained will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Referring to FIG. 1 to FIG. 7 , the present invention provides a method for fabricating a flexible ultra-thin illuminant structure 100 , which includes the following steps:

First step: Referring to FIG. 2, a support substrate 10 is provided. The support substrate 10 includes opposite upper and lower surfaces 12 and 14 , and a polymer flexible dielectric layer 20 is formed on the upper surface 12 of the support substrate 10 . .

The support substrate 10 serves as a mechanical support for the structure formed in the subsequent step, and may be a transparent or opaque substrate such as a glass substrate or a ceramic substrate. Since the support substrate 10 does not form part of the final formed flexible ultra-thin illuminator structure 100 product, the support substrate 10 can be of relatively low cost material as long as it provides the necessary mechanical support. For example, the support substrate 10 may be made of plain glass instead of chemically strengthened glass to reduce the manufacturing cost of the flexible ultra-thin illuminant structure 100.

In addition, after the support substrate 10 is removed from the flexible ultra-thin illuminant structure 100, it can be reused again, so that the manufacturing cost can be further reduced. It is to be noted that the support substrate 10 is not limited to glass, and it may be any other suitable material that can provide mechanical support.

The method of forming the flexible dielectric layer 20 on the upper surface 12 of the support substrate 10 includes coating, printing or molding. The manner of coating may include doctor blade coating, spin coating. After coating, high temperature baking is performed to cure the coated film layer to form a high temperature resistant flexible dielectric layer 20 on the surface of the support substrate 10, the flexible dielectric layer having a thickness of 5 to 50 microns.

The flexible dielectric layer 20 of this thickness range has good mechanical properties including ductility, toughness and thermal stability, while the flexible dielectric layer 20 also has good optical properties, such as high transmittance, for making double-sided. A light transmissive flexible ultra-thin illuminant structure 100.

The flexible dielectric layer 20 may be high temperature resistant polyimide, polyethylene terephthalate (PET), polycarbonate (PC), polyether oxime (PES), polymethyl. Methyl acrylate (PMMA). The high temperature here means a temperature of about 400 degrees.

Preferably, the flexible dielectric layer 20 is formed by selecting a polyimide having a thermal expansion coefficient close to that of the support substrate 10, which can prevent the flexible dielectric layer 20 from warping during curing and subsequently reflowing the light-emitting wafer 40. Warping during welding. The thermal expansion coefficient of the polyimine is in the range of 2 × 10 ^-5 - 3 × 10 ^-5 / ° C.

For example, the flexible dielectric layer 20 is made of polyimine. The support substrate 10 is placed on a movable platform, and a certain ratio of the solution is applied to the support substrate through a coating blade or a coater. The baking is further heated to volatilize part of the solvent and/or to polymerize a part of the components (for example, a polymerizable monomer or a precursor) in the solution to form a polyimide film.

That is, since the flexible dielectric layer 20 is formed by coating, coating, printing or molding, the thickness of the flexible dielectric layer 20 can be controlled, so that the subsequently formed flexible ultra-thin illuminator can be formed. Structure 100 meets the need for thinning. Since the thickness of the flexible dielectric layer 20 is thin, The heat generated by the luminescent wafer can be quickly dissipated to the outside through the flexible dielectric layer without generating heat.

In the second step, referring to FIG. 3, a conductive circuit layer 30 is formed on the surface of the flexible dielectric layer 20. The number of layers of the conductive circuit layer 30 may be one layer or multiple layers.

The conductive wiring layer 30 may be formed on the flexible dielectric layer 20 by sputtering, vapor deposition, or electroplating, and each of the conductive wiring layers 30 has a thickness of 5 to 50 μm.

The material of the conductive circuit layer 30 may be silver, nickel, copper, tin, aluminum or an alloy of the foregoing metal materials, or indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium oxide (IGO), and Transparent conductive material such as indium tungsten oxide (IWO).

The steps of forming the flexible dielectric layer 20 on the surface of the conductive wiring layer 30 and forming the conductive wiring layer 30 on the surface of the flexible dielectric layer 20 are sequentially performed, thereby obtaining a multilayer conductive wiring layer.

Referring to FIG. 4, after the conductive circuit layer 30 is formed, the circuit component 32 is further formed on the surface of the conductive circuit layer 30. Specifically, the circuit component 32 can be formed using a low temperature poly-silicon (LTPS) technique. The circuit component 32 includes a control element for controlling the illumination of the light-emitting wafer and/or a switching element for driving. The circuit component 32 formed by the low-temperature polysilicon technology is actually a low-temperature polysilicon thin film transistor, and the thickness is also controllable, and the size of the circuit component disposed directly on the conductive wiring layer 30 is further reduced, thus reducing the flexible super The thickness of the thin illuminant structure 100.

If the flexible ultra-thin illuminant structure 100 is only used as a simple lighting product, the switching element can be used to stabilize the current and adjust the current to achieve the adjustment of the brightness; if the flexible ultra-thin illuminant structure 100 needs to implement some Control functions, such as controlling the current mode of the current mode or the frequency mode to control the drive circuit, instructing the drive circuit to adjust or change the current in the LED, may use logic control circuit components or smart control components to achieve the corresponding function.

In the third step, referring to FIG. 4, a plurality of light emitting wafers 40 are disposed on the surface of the conductive circuit layer 30. The light emitting wafers 40 are preferably inorganic semiconductor light emitting wafers, each of which has an area of 2.5×10 ⁴ square micrometers. . The light emitting chip 40 is electrically connected to the conductive circuit layer 30. The electrical connection of the light-emitting wafer and the conductive circuit layer 30 includes, but is not limited to, wire bonding, and techniques such as flip chip bonding, solder reflow (Solder Reflow), and the like can also be used. This reflow soldering process is performed under operating conditions of 220 ° C - 320 ° C. In order to prevent the flexible dielectric layer 20 from warping from the support substrate 10 during reflow soldering, the material of the flexible dielectric layer 20 is initially selected. The flexible dielectric layer 20 is formed by selecting a material that is closer to the thermal expansion coefficient of the support substrate 10.

In a fourth step, referring to FIG. 5, a layer of encapsulation layer 50 is formed on the surface of the luminescent wafer 40. The encapsulation layer 50 covers the circuit component 32, the luminescent wafer 40, and the filling circuit component 32 and the luminescent wafer 40. Clearance. The encapsulation layer 50 has a thickness of 1 to 500 micrometers, and the encapsulation layer 50 of the thickness range can satisfy the thinning requirement of the finally formed illuminant structure. The encapsulating layer 50 can be selected from the group consisting of silicone (also known as siloxane), epoxy, and plastic. The encapsulation layer 50 ensures that the light emitted by the luminescent wafer 40 can be emitted and effectively isolates the outside moisture and protects the luminescent wafer 40. Preferably, the thermal expansion coefficient of the encapsulation layer 50 is comparable to the thermal expansion coefficient of the flexible dielectric layer 20. In the present embodiment, the encapsulating layer 50 is polyethylene terephthalate (PET). Thus, it is ensured that the formed illuminant structure has flexible characteristics without warping.

The encapsulation layer 50 may be formed by transfer-molding or injection-molding.

In the fifth step, referring to FIG. 6, the support substrate 10 on the bottom surface of the flexible dielectric layer 20 is removed. After the encapsulation layer 50 is hardened, the support substrate 10 can be removed by bend separation, etching, laser cutting or grinding.

In this embodiment, the lower surface 14 of the support substrate 10 can be scanned by the light beam emitted by the laser light source 60 to remove the support substrate 10. Please refer to FIG. 7 to obtain the flexible ultra-thin illuminator. Structure 100.

Since the flexible dielectric layer 20 is formed by coating a polymer material on the surface of the support substrate 10, the conductive circuit layer 30 is formed by sputtering, vapor deposition or electroplating, so that flexibility can be controlled. The thickness of the dielectric layer 20 and the thickness of the conductive circuit layer 30 are controlled to control the thickness of the flexible ultra-thin illuminant structure 100.

Since the flexible dielectric layer 20 and the encapsulation layer 50 are both capable of transmitting light, the flexible ultra-thin illuminant structure 100 formed is a double-sided illuminating structure.

The flexible ultra-thin illuminant structure 100 has an overall thickness of between 7 and 600 micrometers. Therefore, the flexible ultra-thin illuminant structure 100 can meet the requirements of thinning and flexibility, and can be used for Indicator box, lighting board, backlight module, advertising board and other devices.

Referring to FIG. 7 again, the flexible ultra-thin illuminant structure 100 formed by the above manufacturing method comprises: a flexible dielectric layer 20, and a conductive circuit layer 30 formed on the surface of the flexible dielectric layer 20, formed on the conductive line. The circuit component 32 on the surface of the layer 30, the luminescent wafer 40, and the encapsulation layer 50 formed on the surface of the luminescent wafer 40. The circuit component 32 and the luminescent wafer 40 are electrically connected to the conductive circuit layer 30.

The flexible dielectric layer 20 has a thickness of 5 to 50 microns. The flexible dielectric layer 20 may be high temperature resistant polyimide, polyethylene terephthalate (PET), polycarbonate (PC), polyether oxime (PES), polymethyl. Methyl acrylate (PMMA). The high temperature here means a temperature of about 400 degrees. Since the flexible dielectric layer 20 is colorless and transparent, the flexible ultra-thin illuminant structure 100 can achieve double-sided light output.

The conductive wiring layer 30 has a thickness of 5 to 50 μm.

The circuit component 32 is used to control the illumination of the luminescent wafer 40. In the present embodiment, the implementation circuit component 32 is a low temperature polysilicon thin film transistor.

The encapsulation layer 50 covers a gap between the circuit component 32, the luminescent wafer 40, and the filling circuit component 32 and the luminescent wafer 40. The encapsulation layer 50 has a thickness of from 1 to 500 microns. The encapsulating layer 50 can be selected from the group consisting of silicone (also known as siloxane), epoxy, and plastic. The coefficient of thermal expansion of the encapsulation layer 50 is comparable to the coefficient of thermal expansion of the flexible dielectric layer 20. To prevent the flexible ultra-thin illuminant structure 100 from warping.

The flexible ultra-thin illuminant structure 100 has an overall thickness of between 7 and 600 micrometers. Therefore, the flexible ultra-thin illuminant structure 100 can meet the requirements of thinning, flexible, and double-sided light-emitting. .

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and the scope of the patent application of the present invention is not limited thereto. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

Claims (10)

A flexible ultra-thin illuminant structure comprising: a flexible dielectric layer, a conductive circuit layer formed on a surface of the flexible dielectric layer, a light-emitting chip formed on a surface of the conductive circuit layer, and an illuminating wafer covering the luminescent wafer An encapsulation layer, a surface of the conductive circuit layer further formed with circuit elements, the circuit element comprising a control element for controlling illumination of the illumination wafer and/or a switching element for driving the illumination wafer, the encapsulation layer Covering the light-emitting chip, the circuit component, and filling a gap between the circuit component and the light-emitting chip. The flexible ultra-thin illuminant structure according to claim 1, wherein the encapsulation layer has a thickness of from 1 micrometer to 500 micrometers, and a thermal expansion coefficient of the encapsulation layer is consistent with a thermal expansion coefficient of the dielectric layer. The flexible ultra-thin illuminant structure according to claim 1, wherein the flexible dielectric layer is a transparent polymer film, and the flexible dielectric layer has a thickness of 5 μm to 50 μm, and the conductive The thickness of the wiring layer is 5 to 50 microns. A method for fabricating a flexible ultra-thin illuminant structure, comprising the steps of: providing a support substrate, forming a flexible dielectric layer on a surface of the support substrate; forming a conductive circuit layer on a surface of the flexible dielectric layer; a surface of the conductive circuit layer is provided with a plurality of light-emitting wafers; an encapsulation layer is formed on a surface of the light-emitting chip, the encapsulation layer covers the light-emitting chip and fills a gap between the plurality of light-emitting wafers; The support substrate on the bottom surface of the flexible dielectric layer is removed to obtain a flexible ultra-thin illuminant structure. The method of fabricating a flexible ultra-thin illuminant structure according to claim 4, further comprising the step of forming a circuit component on the surface of the conductive wiring layer by using a low-temperature polysilicon technology after forming the conductive wiring layer. The method for fabricating a flexible ultra-thin illuminant structure according to claim 4, wherein the conductive circuit layer is formed on the flexible dielectric layer by sputtering, vapor deposition or electroplating. The conductive wiring layer has a thickness of 5 to 50 μm. The method for fabricating a flexible ultra-thin illuminant structure according to claim 4, wherein the support substrate is removed by bending separation, etching, laser cutting or grinding. The method for fabricating a flexible ultra-thin illuminant structure according to claim 4, wherein the flexible dielectric layer is a transparent polymer film, and the flexible dielectric layer has a thickness of 5 micrometers to 50 micrometers. The method for fabricating a flexible ultra-thin illuminant structure according to claim 4, wherein a thermal expansion coefficient of the encapsulation layer is consistent with a thermal expansion coefficient of the dielectric layer, and a thickness of the encapsulation layer is between 1 micrometer. Up to 500 microns. The method for fabricating a flexible ultra-thin illuminant structure according to claim 9, wherein the encapsulating layer is one of polyethylene terephthalate, epoxy resin, and siloxane.