Chip package

Abstract

A chip package includes a substrate, a light emitting diode chip, and an optical layer. The light-emitting diode chips are arranged on the substrate along a stacking direction. The optical layer is disposed on the light emitting diode chip along the stacking direction. The refractive index of the optical layer decreases gradually in the stacking direction.

Description

Technical Field

[0001] The invention relates to an optical device, and in particular to a chip package. Background Art

[0002] Existing light-emitting diode chips are prone to total reflection at the light-emitting surface of the chip, resulting in low light extraction efficiency. Summary of the invention

[0003] The invention provides a chip package with good light extraction efficiency.

[0004] According to an embodiment of the present invention, a chip package is provided, comprising a substrate, a light-emitting diode chip and an optical layer. The light-emitting diode chip is arranged on the substrate along a stacking direction. The optical layer is arranged on the light-emitting diode chip along the stacking direction. The refractive index of the optical layer gradually decreases along the stacking direction.

[0005] According to an embodiment of the present invention, the optical layer includes a first surface away from the LED chip and a second surface close to the LED chip, and the refractive index of the optical layer at the first surface is greater than 1.0 and less than or equal to 1.2.

[0006] According to an embodiment of the present invention, the refractive index of the optical layer at the second surface is less than or equal to 2.5.

[0007] According to an embodiment of the present invention, the optical layer includes a plurality of optical sub-layers stacked along a stacking direction.

[0008] According to an embodiment of the present invention, the chip package further includes phosphors disposed in the optical layer.

[0009] According to an embodiment of the present invention, the particle size of the phosphor gradually decreases along the stacking direction.

[0010] According to an embodiment of the present invention, the chip package further includes a plurality of scattering particles disposed in the optical layer.

[0011] According to an embodiment of the present invention, the phosphor and the scattering particles are disposed in different optical sublayers. The phosphor is disposed in at least one optical sublayer close to the LED chip, and the scattering particles are disposed in at least one optical sublayer far from the LED chip.

[0012] According to an embodiment of the present invention, the chip package further includes an insulating structure disposed on the substrate and surrounding the light emitting diode chip and the optical layer.

[0013] According to an embodiment of the present invention, the optical layer includes a first surface away from the LED chip, the insulating structure includes a top surface away from the substrate, and the distance between the top surface of the insulating structure and the substrate is greater than or equal to the distance between the first surface and the substrate.

[0014] According to an embodiment of the present invention, the chip package further includes a metal reflective layer disposed on a surface of the insulating structure facing the light emitting diode chip and the optical layer.

[0015] According to an embodiment of the present invention, the metal reflective layer includes a concave surface facing the light emitting diode chip and the optical layer.

[0016] Based on the above, the chip package provided by the embodiment of the present invention uses an optical layer with a gradient refractive index to improve the light extraction efficiency of the LED chip, and also configures phosphors with a color conversion function and scattering particles with a light uniforming function in the optical layer. The chip package also uses a metal reflector cup surrounding the LED chip and the optical layer to collect light.

[0017] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of a chip package according to some embodiments of the present invention is shown.

[0019] Figure 2 A schematic diagram showing an optical layer according to an embodiment of the present invention.

[0020] Figure 3 A schematic diagram showing an optical layer according to an embodiment of the present invention.

[0021] Figure 4 A schematic diagram of a chip package according to an embodiment of the present invention is shown.

[0022] Description of Figure Numbers:

[0023] 1, 2: Chip packaging;

[0024] 100: optical layer;

[0025] 200: light emitting diode chip;

[0026] 200T: bright surface;

[0027] 300: insulation structure;

[0028] 300R: metal reflective layer;

[0029] PP: phosphor;

[0030] SP: scattering particles;

[0031] SB: substrate;

[0032] S1: first surface;

[0033] S2: second surface;

[0034] SL1, SL2, SL3, SL n : Optical sublayer;

[0035] ST: Top DETAILED DESCRIPTION

[0036] Reference Figure 1 , which shows a schematic diagram of a chip package according to some embodiments of the present invention.

[0037] In the first embodiment of the present invention, the chip package 1 includes a substrate SB, a light-emitting diode chip 200, an optical layer 100 and an insulating structure 300. The substrate SB is a circuit substrate. The light-emitting diode chip 200 is arranged on the substrate SB along the Z direction (stack direction). The optical layer 100 includes a first surface S1 and a second surface S2, and is arranged on the light-emitting surface 200T of the light-emitting diode chip 200 along the Z direction. The second surface S2 directly contacts the light-emitting surface 200T. The refractive index of the optical layer 100 gradually decreases along the Z direction. Compared with a comparative example in which the optical layer 100 is not arranged on the light-emitting surface 200T of the light-emitting diode chip 200, the first embodiment can avoid total reflection at the light-emitting surface 200T of the light-emitting diode chip 200 by arranging the optical layer 100 with a gradually changing refractive index on the light-emitting diode chip 200, thereby improving the light extraction efficiency of the light-emitting diode chip 200. In some embodiments, the refractive index of the optical layer 100 can be continuously gradually changing.

[0038] In some embodiments, the refractive index of the optical layer 100 at the second surface S2 is less than or equal to 2.5 to avoid total reflection at the interface between the LED chip 200 and the optical layer 100. In addition, the refractive index of the optical layer 100 at the first surface S1 is greater than 1.0 and less than or equal to 1.2 to avoid total reflection at the interface between the optical layer 100 and air.

[0039] In a second embodiment of the present invention, Figure 1 As shown, the optical layer 100 includes a plurality of optical sub-layers SL1, SL2, SL3, SL4, SL5, SL6, SL7, SL8, SL9, SL10, SL11, SL22, SL33, SL44, SL55, SL56, SL57, SL58, SL60, SL71, SL72, SL73, SL74, SL n , wherein n is any positive integer greater than 3. The second surface S2 of the optical layer 100 is on the optical sub-layer SL1, and the first surface S1 of the optical layer 100 is on the optical sub-layer SL n Multiple optical sub-layers SL1, SL2, SL3…SLn The refractive index of the optical sublayer SL1 gradually decreases, wherein the refractive index of the optical sublayer SL1 is greater than the refractive index of the optical sublayer SL2, the refractive index of the optical sublayer SL2 is greater than the refractive index of the optical sublayer SL3, and so on. The refractive index of the optical sublayer SL1 may be less than or equal to 2.5 to avoid total reflection at the interface between the light emitting diode chip 200 and the optical layer 100. n The refractive index may be greater than 1.0 and less than or equal to 1.2 to avoid total reflection at the interface between the optical layer 100 and air.

[0040] The chip package 1 may further include a phosphor PP and a plurality of scattering particles SP disposed in the optical layer 100, wherein the phosphor PP is used to absorb light from the LED chip 200 to perform color conversion and emit fluorescence, and the scattering particles SP are used to homogenize the light from the LED chip 200. Figure 1 As shown, the phosphor PP and the scattering particles SP can be disposed in different optical sublayers. In some embodiments, the phosphor PP can be disposed in some optical sublayers close to the LED chip 200, and the scattering particles SP can be disposed in some optical sublayers far from the LED chip 200, but not limited thereto.

[0041] In a third embodiment of the present invention, Figure 2 As shown, the optical layer 100 includes a plurality of optical sub-layers SL1, SL2, SL3, SL4, SL5, SL6, SL7, SL8, SL9, SL10, SL11, SL22, SL33, SL44, SL55, SL56, SL57, SL58, SL60, SL71, SL72, SL73, SL74, SL n The phosphor PP and the plurality of scattering particles SP are uniformly distributed in the optical layer 100 .

[0042] In a fourth embodiment of the present invention, Figure 3 As shown, the optical layer 100 includes a plurality of optical sub-layers SL1, SL2, SL3, SL4, SL5, SL6, SL7, SL8, SL9, SL10, SL11, SL22, SL33, SL44, SL55, SL56, SL57, SL58, SL60, SL71, SL72, SL73, SL74, SL n . The phosphor powder PP is arranged in some optical sublayers close to the second surface S2 (i.e., close to the LED chip 200), and the scattering particles SP are arranged in some optical sublayers close to the first surface S1 (i.e., far away from the LED chip 200). The closer the phosphor powder PP is to the second surface S2, the larger its particle size is; the farther the phosphor powder PP is from the second surface S2, the smaller its particle size is. In addition, the phosphor powder PP with a smaller particle size can be arranged in the gap between the phosphor powders PP with a larger particle size to improve the color conversion rate.

[0043] In order to fully illustrate the various embodiments of the present invention, other embodiments of the present invention will be described below. It must be noted that the following embodiments use the component numbers and some contents of the previous embodiments, wherein the same numbers are used to represent the same or similar components, and the description of the same technical contents is omitted. For the description of the omitted parts, please refer to the previous embodiments, and the following embodiments will not be repeated.

[0044] In a fifth embodiment of the present invention, Figure 4 As shown, the chip package 2 includes a substrate SB, an LED chip 200, an optical layer 100 and an insulating structure 300. The insulating structure 300 is disposed on the substrate SB and surrounds the LED chip 200 and the optical layer 100. The chip package 2 also includes a metal reflective layer 300R. The metal reflective layer 300R is disposed on the surface of the insulating structure 300 facing the LED chip 200 and the optical layer 100, and the metal reflective layer 300R includes a concave surface facing the LED chip 200 and the optical layer 100. Accordingly, the metal reflective layer 300R is formed into a metal reflective cup, which can reflect light from the LED chip 200 and the optical layer 100 to improve the forward light output intensity of the chip package 2. Figure 4 In the chip package 2 shown in FIG. 1 , the insulating structure 300 includes a top surface ST away from the substrate SB, and the distance between the top surface ST and the substrate SB is equal to the distance between the first surface S1 and the substrate SB (eg, Figure 4 As shown, the top surface ST is coplanar with the first surface S1), but the present invention is not limited thereto. In some embodiments, the distance between the top surface ST and the substrate SB may be greater than the distance between the first surface S1 and the substrate SB to ensure the light collecting function of the metal reflective cup.

[0045] Based on the above, the chip package provided by the embodiment of the present invention uses an optical layer with a gradient refractive index to improve the light extraction efficiency of the LED chip, and also configures phosphors with a color conversion function and scattering particles with a light uniforming function in the optical layer. The chip package also uses a metal reflector cup surrounding the LED chip and the optical layer to collect light.

Claims

1. A chip package, characterized in that: include: substrate; A light emitting diode chip is arranged on the substrate along a stacking direction; and an optical layer, arranged on the light emitting diode chip along the stacking direction, The refractive index of the optical layer gradually decreases along the stacking direction.

2. The chip package according to claim 1, characterized in that: The optical layer includes a first surface away from the light emitting diode chip and a second surface close to the light emitting diode chip. The refractive index of the optical layer at the first surface is greater than 1.0 and less than or equal to 1.

2.

3. The chip package according to claim 2, characterized in that: The refractive index of the optical layer at the second surface is less than or equal to 2.

5.

4. The chip package according to claim 1, characterized in that: The optical layer includes a plurality of optical sub-layers stacked along the stacking direction.

5. The chip package according to claim 4, characterized in that: It also includes fluorescent powder, which is arranged in the optical layer.

6. The chip package according to claim 5, characterized in that: The particle size of the phosphor gradually decreases along the stacking direction.

7. The chip package according to claim 5, characterized in that: It also includes a plurality of scattering particles, which are arranged in the optical layer.

8. The chip package according to claim 7, characterized in that: The phosphor and the scattering particles are arranged in different optical sublayers. The phosphor is arranged in at least one optical sublayer close to the LED chip, and the scattering particles are arranged in at least one optical sublayer far from the LED chip.

9. The chip package according to claim 1, characterized in that: The invention also comprises an insulating structure which is arranged on the substrate and surrounds the light emitting diode chip and the optical layer.

10. The chip package according to claim 9, characterized in that: The optical layer includes a first surface away from the light emitting diode chip, and the insulating structure includes a top surface away from the substrate, and a distance between the top surface and the substrate is greater than or equal to a distance between the first surface and the substrate.

11. The chip package according to claim 9, characterized in that: It also includes a metal reflective layer, which is disposed on the surface of the insulating structure facing the light-emitting diode chip and the optical layer.

12. The chip package according to claim 11, characterized in that: The metal reflective layer includes a concave surface facing the light emitting diode chip and the optical layer.

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