TWI624968B - Led package structure provided with a predetermined view angle, led package module, manufacturing method therefor - Google Patents

Abstract

A method for forming a light emitting diode package structure capable of providing a predetermined viewing angle, comprising at least the steps of: placing a flip chip on a carrier substrate; filling a gap between the electrodes of the flip chip of the flip chip Supporting the flip chip; laser stripping a growth substrate of the flip chip to form a thinned wafer, and exposing an epitaxial structure of the thinned wafer; roughening the thinned wafer Exposed the epitaxial structure; providing a viewing angle adjustment structure to the thinned wafer; and selecting a predetermined viewing angle, adjusting the viewing angle adjustment structure according to a linear regression analysis formula to achieve the predetermined viewing angle.

Description

A light emitting diode package structure, a light emitting diode package module, and a predetermined viewing angle are provided. And forming method thereof

The invention relates to a light emitting diode package structure, a light emitting diode package module and a forming method thereof, which can provide a predetermined viewing angle, in particular to a light emitting diode package structure having a viewing angle adjusting structure for linear regression analysis. The algorithm adjusts the viewing angle adjustment structure to achieve the predetermined viewing angle.

In general, LED applications such as automotive and flashlights often require a smaller viewing angle to match the secondary optical lens to achieve the desired shape and optimum light utilization. At present, the optical design of the lens is often used to adjust the viewing angle of the LED, and the product is usually required to be thinner, for example, a thin flash Fresnel lens is used for the mobile phone flash. In addition to the smaller viewing angles, in order to meet the needs of different applications, specific viewing angles are often required to match the secondary optics of a particular design. Secondary optical lenses add cost in both design and manufacturing.

Plastic Electrode Wafer Carrier (PLCC) LED or Lamp type LED is designed with a cup design or a package structure to control the viewing angle. To adjust the viewing angle, it is necessary to develop the relevant mold, which takes time, equipment and cost. high.

Molding type LEDs can be adjusted through the lens design or the shape of the LED. Generally, in order to achieve the effect of narrowing the viewing angle, a reflective wall structure is added to the periphery of the LED, but the reflective wall absorbs the lateral light of the wafer, causing a decrease in brightness.

The technical problem to be solved by the present invention is to provide a method for forming a light emitting diode package structure and a light emitting diode structure capable of providing a predetermined viewing angle, and adjusting the overall thickness of the wavelength conversion layer and the reflectivity of the reflective wall by adjusting the viewing angle adjustment structure. And the corresponding height of the two, and the predetermined viewing angle is achieved, so that the elastic space of the optical design is larger.

In order to further understand the technology, method and effect of the present invention in order to achieve the intended purpose, reference should be made to the detailed description and drawings of the present invention. The drawings and the annexed drawings are intended to be illustrative and not to limit the invention.

100‧‧‧Flip-chip wafer

100a‧‧‧ first surface

100b‧‧‧ second surface

10‧‧‧ epitaxial structure

11‧‧‧buffer layer

12‧‧‧N type semiconductor layer

121‧‧‧ upper surface

1211‧‧‧Corner

13‧‧‧Lighting layer

14‧‧‧N type contact pad

15‧‧‧P type semiconductor layer

17‧‧‧P type contact pad

S‧‧‧ gap

20‧‧‧ Growth substrate

30‧‧‧Loading substrate

31, 32‧‧‧ circuit structure

40‧‧‧Filling layer

50, 50a, 50b‧‧‧ wavelength conversion layer

70‧‧‧Reflection wall

200, 200a, 200b‧‧‧Lighting chip diode structure

400‧‧‧Light Emitting Diode Structure

500‧‧‧Light Emitting Diode Module

H0‧‧‧ epitaxial structure thickness

H1‧‧‧ Thickness from the top surface of the wavelength conversion layer to the top surface of the epitaxial structure

1 is a schematic view of wafer bonding of a light emitting diode structure of the present invention.

1A is a schematic view showing an embodiment of a flip chip structure of a flip chip of the present invention.

2 is a schematic view showing the flip chip of the present invention adhered to a carrier substrate.

3 is a schematic view showing the stripping process of the flip chip of the present invention.

4 is a schematic view showing a roughened epitaxial structure of a thinned wafer of the present invention.

4A is a partially enlarged schematic view showing a portion A of FIG. 4 of the present invention.

Figure 5 is a schematic illustration of a thinned wafer bonded wavelength conversion layer of the present invention.

5A is a schematic view of another embodiment of a thinned wafer bonded wavelength conversion layer of the present invention.

Figure 5B is a schematic illustration of yet another embodiment of a thinned wafer bonded wavelength conversion layer of the present invention.

5C is a schematic view showing still another embodiment of the thinned wafer bonding wavelength conversion layer of the present invention.

Figure 6 is a graph showing the coordinates of the data of the first experimental example of the present invention.

Fig. 7 is a plan view showing a 0 degree angle of view of the wavelength conversion layer not attached to Fig. 4 according to the present invention.

FIG. 8 is a schematic diagram of a light emitting diode package structure having a reflective wall according to the present invention.

FIG. 8A is a schematic diagram of a light emitting diode package structure with another reflective wall according to the present invention.

FIG. 8B is a schematic diagram of a light emitting diode package structure with a reflective wall in FIG. 5C according to the present invention. FIG.

Figure 9 is a plan view showing the reflectance of the reflective wall in accordance with Figure 8 in accordance with Figure 8 of the present invention.

Figure 10 is a graph showing the reflectance of different reflective wall materials and light wavelengths of the present invention.

Fig. 10A is a graph showing the coordinates of experimental data according to the second experimental example of the present invention.

Fig. 10B is a coordinate distribution diagram of experimental data according to a third experimental example of the present invention.

11 is a top plan view of a light emitting diode package module of the present invention.

Please refer to FIG. 1 , which is a schematic diagram of wafer bonding of a light emitting diode structure of the present invention. The present invention provides a method of fabricating a light emitting diode structure. First, the first step is to provide a flip chip 100. The flip chip 100 has a growth substrate 20 and an epitaxial structure 10 formed on the growth substrate 20, and at least a pair of wafer metal pads 14, 17 are formed on the epitaxial structure 10, the pair of wafer metal The pads 14, 17 have a spacing gap S.

The growth substrate 20 of the present embodiment may be a sapphire substrate. The flip chip 100 has a first surface 100a (such as the upper side of FIG. 1) and a second surface 100b (such as the lower side of FIG. 1) opposite to each other, and the first surface side is a growth substrate 20, and the second surface side There are at least one P-contact pad 17 and at least one N-contact pad 14 as electrodes, and a gap S between the two contact pads (14, 17).

Referring to FIG. 1A, an epitaxial structure 10 of each flip chip 100 is formed on the upper surface of the growth substrate 20. The epitaxial structure 10 includes a buffer layer 11, an N-type semiconductor layer 12, a light-emitting layer 13, and a P-type semiconductor layer. 15. The buffer layer 11 may be undoped gallium nitride (undoped-GaN), the N-type semiconductor layer 12 may be N-type gallium nitride, and the light-emitting layer 13 may be a multilayer quantum well (MQW). The semiconductor structure; the P-type semiconductor layer 15 may be a P-type gallium nitride. An N-type contact pad 14 is connected to the N-type semiconductor layer 12, and a P-contact pad 17 is connected to the P-type semiconductor layer 15. Furthermore, the spaced gaps S also extend between the corresponding P-type semiconductor layer 15 and the N-type semiconductor layer 12.

The layered structure of the above epitaxial structure 10 is merely an example. The present invention is not limited to the layered structure of the epitaxial structure 10 described above. For example, the buffer layer 11 may be omitted, and the N-type semiconductor layer 12 may be directly formed on the growth substrate 20. Further, the P-type semiconductor layer 15 may be additionally formed with a metal layer, or a transparent electrode layer, etc., and then the above-described P-type contact pad 17 is formed.

Referring to FIG. 1 again, the flip chip 100 of the present invention is bonded to a carrier substrate 30. The carrier substrate 30 has circuit structures 31 and 32. The N-type contact pads 14 as electrodes are in contact with the P-type contact pads 17 to the circuit structure. 31, 32. The primer material is then filled into the gap S between the N-type contact pad 14 and the P-type contact pad 17. The circuit structures 31, 32 may extend to the bottom surface or other locations of the carrier substrate 30 as desired by the design.

As shown in FIG. 2, a schematic diagram of a flip chip of the present invention bonded to a substrate is shown. The underfill material of this embodiment is filled in the gap S between the flip chip 100 and the carrier substrate 30 to form a filling layer 40.

It should be noted that, in addition to filling the gap S between the N-type contact pad 14 and the P-type contact pad 17, the filling layer 40 of the present embodiment is preferably filled in the second surface of the flip-chip wafer 100. All the space between the 100b and the carrier substrate 30, in order to achieve the flip-chip wafer 100 can effectively obtain the support substrate 30 support by filling the layer 40. In other words, the filling layer 40 needs to contact the second surface 100b of the flip chip 100 and the upper surface of the carrier substrate 30, and surround the N-type contact pad 14, the P-type contact pad 17, and the periphery of the circuit structures 31, 32. Furthermore, the filling layer 40 can also extend to the position of the epitaxial structure 10.

FIG. 3 is a schematic view showing a stripping process of the flip chip of the present invention. In the second flow of the present invention, the lifted substrate 20 of the flip chip 100 is subjected to laser lift off (LLO), that is, a thin type forming the non-growth substrate 20 of the present invention. Wafers, also known as film flip-chips. Laser stripping is preferably performed at the wafer level to avoid excessive stresses at the wafer level of laser lift, which causes severe warpage of the entire wafer. For example, the present embodiment may use an ultraviolet laser such as a KrF excimer laser having a wavelength of 248 nm. The advantage is that gallium nitride (GaN) has a high absorption coefficient for the 248 nm 氪-fluorine excimer laser, and the laser energy is mostly absorbed at the interface. In contrast, gallium nitride (GaN) has a small absorption coefficient for a 355 nm ytterbium-doped yttrium aluminum garnet solid-state laser (Nd:YAG laser), and the penetration depth of the laser is deep, resulting in most defects being inside the material. form.

The laser stripping process is specifically exemplified as follows. When the growth substrate 20 is a sapphire substrate, first, focusing on the buffer layer 11, this embodiment is a gallium nitride layer, and the sapphire substrate is stripped with an appropriate laser energy, such as 750 to 1100 mJ. (micro joules). Taking a 45 mil (Mil) flip chip as an example, 950 mJ (microjoules) can be completely stripped. Insufficient energy causes the sapphire substrate to be peeled off incompletely, resulting in damage to the luminescent layer. Furthermore, the size of the laser beam must be slightly larger than the size of the flip chip to be stripped. Preferably, the side length is more than 40 micrometers (um) above the flip chip. For example, a 45 mil flip-chip wafer has a side length of 1123 micrometers (um), 60 micrometers (um) left on each side, and a laser beam size of 1260 micrometers (um) to ensure that the sample is completely affected. Laser irradiation. In addition, since the energy of the laser light source is Gaussian, if the energy is uneven, the wafer may be damaged, so the position of the light source can be adjusted according to the situation.

4 and 4A are schematic views showing a roughened epitaxial structure of a thinned wafer of the present invention, and FIG. 4A is an enlarged view of a portion A in FIG. The third flow of the present invention is to roughen a semiconductor layer of the epitaxial structure 10 exposed after the substrate 20 is grown by peeling off; wherein the semiconductor layer is an N-type semiconductor layer 12, and this embodiment is an N-type gallium nitride layer. The flow of roughening the semiconductor layer includes the following steps: wet etching with an alkali hydroxide until the pyramid 1211 formed on the upper surface 121 of the semiconductor layer occupies 20% or more of the surface area. Where necessary, the above-described wet etching process further includes etching with ultraviolet light or heat to increase the formation of pyramids.

In this embodiment, the flow of the above wet etching includes the following steps: Then, the flip-chip wafer 100 from which the growth substrate 20 has been removed is immersed in a 3M (volume molar concentration mol/L) potassium hydroxide (KOH) solution for 10 minutes or more to roughen the N-type semiconductor layer with hydroxide ions. The surface of 12. Then, the flip chip 100 is taken out and oscillated with deionized water for a predetermined time, for example, 10 minutes. If there are residual gallium metal particles, they can be removed by a higher concentration of potassium hydroxide (KOH) or an acid such as hydrochloric acid (HCl).

Please refer to FIG. 5 , which is a schematic diagram of a bonding wavelength conversion layer of a thinned wafer of the present invention. The fourth flow of the present invention is to bond a light transmissive wavelength conversion layer 50 to the epitaxial structure 10 of the thinned wafer. According to the embodiment of FIG. 1A, that is, the N-type semiconductor layer 12 on the top surface of the epitaxial structure 10. Thus, a light emitting diode package structure 200 is formed. The wavelength conversion layer 50 of the present embodiment is a light transmissive layer having a wavelength conversion material, such as a phosphor powder sheet. The wavelength conversion layer 50 of the present invention may be a phosphor powder sheet or a gel material containing a wavelength converting material.

For example, the process of bonding the wavelength conversion layer 50 includes attaching a phosphor powder sheet to the epitaxial structure 10, that is, the phosphor powder sheet is attached to the epitaxial structure as shown in FIG. 1A. A preferred embodiment of the N-type semiconductor layer 12 of 10, wherein the phosphor powder sheet may be a sheet of phosphor powder mixed with colloid, ceramic or glass, and the hardness of the phosphor sheet is greater than that of Shaw (Shore). The hardness D40, the thickness can be controlled between 60 micrometers (μm) and 350 micrometers (μm). The size can be greater than or equal to the epitaxial structure 10 of the thinned wafer. One practical approach is to ensure a complete fit with a die attaching machine patch, about 120g of lightly pressed thinned wafer (removing the grown substrate 20 from the flip chip 100).

For example, in the case of a rubber material, the above-described process of adhering the wavelength conversion layer includes directly covering the epitaxial structure 10 with a rubber material. In a practical practice, the adhesive material having the wavelength converting material can cover all exposed surfaces of the thinned wafer (ie, the flip-chip wafer from which the grown substrate 20 has been removed), including the upper surface 121 of the epitaxial structure 10 and four of them. side. As shown in FIG. 5A, the wavelength conversion layer 50a extends to both sides of the epitaxial structure 10, completely covering the epitaxial structure 10, and forming a light-emitting chip diode structure. 200a. In addition, since the rubber material directly contacts the flip chip 100, it is necessary to use a heat-resistant and light-resistant glue such as a silicone having a refractive index of 1.4.

Please refer to FIG. 5B , which is a schematic diagram of still another embodiment of the flip chip wafer bonding wavelength conversion layer of the present invention. The difference from the above embodiment is that the width of the wavelength conversion layer 50b of the light-emitting wafer diode structure 200b is substantially equal to the width of the epitaxial structure 10. Please refer to FIG. 5C again, which is a schematic diagram of still another embodiment of the flip-chip wafer bonding wavelength conversion layer of the present invention. The width of the wavelength conversion layer 50b of the luminescent wafer diode structure 200b of the present embodiment is substantially equal to the width of the epitaxial structure 10. Further, the filling layer 40 is further extended to substantially cover the side of the epitaxial structure 10. In addition, the filling layer 40 of the present embodiment is preferably an opaque primer material that frames the light-emitting layer of the thinned wafer. The opaque primer material can reduce the overall viewing angle and has the function of controlling the viewing angle. The rubber material can be made of silicone or epoxy resin, and the white primer material can maintain the brightness. In summary, the width of the wavelength conversion layer of the present invention may be greater than or equal to the width of the epitaxial structure 10.

In this embodiment, the growth substrate 20 is removed, and an Epistar 45 mil flip chip is taken as an example. The viewing angle of the blue light wafer itself is about 130 degrees. If the growth substrate 20 is removed, the thickness can be reduced by about 140 μm, and the light is reduced. The refraction and scattering, the epitaxial structure 10, that is, the thickness of the light-emitting layer of the wafer (refer to H0 of FIG. 5A) is only about 8 to 10 μm, and the viewing angle can reach about 117 degrees. In addition, since the thickness is less than 10 μm, almost all of the blue light is positively emitted, and most of the blue light can be converted into white light by the wavelength conversion layer. Further, after the growth substrate 20 is removed, the wavelength conversion layers 50, 50a, 50b having the wavelength conversion material can enhance the overall structure, and the blue light leakage of the light-emitting layer 13 can be prevented by controlling the width of the light-transmissive wavelength conversion layer.

One of the features of this embodiment is that the overall viewing angle of the light emitting diode package structure 200 is changed by controlling the thickness of the wavelength conversion layer 50. The LED package structure 200 of the desired viewing angle is further fabricated according to the intended viewing angle. The above wavelength conversion layer can be regarded as a viewing angle adjustment structure.

In this embodiment, an experiment is carried out according to the structure of FIG. 5A, and an EPISTAR 45-mil wafer flip-chip wafer is subjected to a laser lift-off growth substrate as an example, wherein H0 represents epitaxy after removing the growth substrate 20. The thickness of the structure 10 is about 10 μm; H1 represents the thickness of the top surface of the wavelength conversion layer to the top surface of the epitaxial structure 10. Wherein the thickness of H0+H1 represents the overall thickness of the wavelength conversion layer by H, which is equal to the thickness from the top surface of the wavelength conversion layer 50a to the bottom surface of the epitaxial structure 10. Please refer to Table 1 of the first experimental example below:

From the above Table 1, as the thickness of the wavelength conversion layer increases, the viewing angle increases. When the overall thickness of the wavelength conversion layer is adjusted from 350 μm to 60 μm, the viewing angle can be 120.4 degrees from 133.7 degrees. The measurement of the above viewing angle is in the range of 50% of the maximum light intensity of the light pattern, and in the comparative example, the 0 degree viewing angle pattern of the wavelength conversion layer is not attached according to FIG. As shown in FIG. 6, the present invention draws a graph of the data of the first experimental example according to the above Table 1, and can analyze the relationship between the viewing angle and the overall thickness of the wavelength conversion layer in a substantially linear relationship. The present invention is based on linear regression analysis, and based on the correlation between the independent variable X (the overall thickness of the wavelength conversion layer) and the variable Y (angle of view), a method for predicting the linear regression equation of X and Y can be obtained. The following relationship: Equation 1: Angle of view = 117 ° + 0.05 × overall thickness of the wavelength conversion layer (H)

In summary, the present invention can be achieved according to the linear regression equation described above, and the thickness of the corresponding wavelength conversion layer is attached to the epitaxial structure 10 according to the viewing angle required for the product of the LED package structure. This can avoid unnecessary tests.

Please refer to FIG. 8 , which is a schematic diagram of a light emitting diode package structure with a reflective wall according to the present invention. This process can be called a white wall molding process. In addition to the wavelength conversion layer 50 of the above embodiment, the present embodiment forms the light emitting diode package structure 400 with the wavelength conversion layer 50 and the reflection wall 70 which are larger than the epitaxial structure 10. The reflective wall 70 covers the epitaxial structure 10 and the wavelength conversion layer 50. The reflective wall 70 is equal to or slightly higher than the top surface of the wavelength conversion layer 50 by 10 to 50 μm, and may or may not cover the top surface of the wavelength conversion layer 50. An embodiment of the method, for example, coating a white resin with the periphery of the epitaxial structure 10 and the wavelength conversion layer 50 in a molding manner to reduce the viewing angle. The advantage is that the white resin can be used as a reflective cup, and since the light-emitting layer of the wafer has only 10 μm left, the reflective cup structure has little influence on the lateral light, and the viewing angle can be reduced in a structure in which the brightness is not reduced. The wavelength conversion layer 50 and the reflection wall 70 can be regarded as a viewing angle adjustment structure.

One of the advantages of this embodiment is that the different viewing angles of the reflective wall 70 are utilized to adjust the overall viewing angle of the LED package structure 400. The specific experiment is as follows: Control the reflectivity of the reflective wall to adjust the overall viewing angle. From 0% reflectance to 100% reflectivity, the reflective particles of different proportions are infiltrated into the four reflective wall materials to form the number 矽. Test sample of resin 1-4.

In the second experimental example of the present invention, the reflective wall 70 is equal to the top surface of the wavelength conversion layer 50 (as shown in FIG. 8); in the third experimental example of the present invention, the reflective wall 70 is higher than the top surface of the wavelength conversion layer 50 ( 8A or 8B, wherein FIG. 8A is the structure of FIG. 5, and FIG. 8B is the structure of FIG. 5C, wherein the reflective wall 70 is 10 to 50 μm higher than the top surface of the wavelength conversion layer 50 to reduce the viewing angle; The higher the reflectivity of the wall (greater than 70%), the more obvious the effect.

According to FIG. 8, the reflectivity of the reflective wall is 100%. After the measurement, the viewing angle can be reduced from 142.0 degrees to 115.3 degrees, and 115.3 degrees is referred to the light pattern of FIG. The viewing angle experiment table of the light emitting diode package structure with the reflective wall is organized into the following list 2.

The color of the reflective wall material in Table 2 above and the reflectance for the light wavelength of 449 nm are as follows: the resin 1 color is transparent, the reflectance is 0%; the resin 2 color is gray-white, and the reflectance is 74.7%; the color of the enamel resin 3 is off-white, the reflectance is 89.1%; the color of the enamel resin 4 is white (white), and the reflectance is 100%.

Referring to FIG. 10, the reflectance of the reflective wall 70, the number of the enamel resins 2 to 4 of the present embodiment is an experimental sample having a plate-shaped thickness of 0.5 mm, and the wavelength of the light is selected to be 449 nm. In fact, it can be applied to a wavelength greater than 425 nm or more, that is, there is a significant difference. When the wavelength is greater than 450 nm, the reflectivity of the resin 3 to 4 begins to decrease.

Please refer to FIG. 10A , which is a coordinate distribution diagram of experimental data according to a second experimental example of the present invention. From the coordinate map of the second experimental example, the relationship between the viewing angle and the reflectance of the reflective wall can be analyzed substantially linearly. According to the linear regression analysis, according to the correlation between the self-variable X (reflectance of the reflective wall, R) and the variable Y (angle of view), the method of predicting the linear regression equation of X and Y is established, and the following relationship can be obtained. Equation: Equation 2: Viewing angle = 141.8-0.2709 × Reflectivity of reflective wall%

Furthermore, please refer to FIG. 10B , which is a coordinate distribution diagram of experimental data according to a third experimental example of the present invention. The reflective wall 70 is 20 μm higher than the top surface of the wavelength conversion layer 50. From the coordinate plot of the third experimental example, the relationship between the angle of view and the reflectivity of the reflective wall can be analyzed. Sexual relationship. According to the linear regression analysis, the present invention establishes a linear regression equation of X and Y for prediction based on the correlation between the self-variable X (reflectance of the reflective wall) and the variable Y (viewing angle), and the following relationship can be obtained: Equation 3: Angle of view = 141.9-0.2809 × Reflectivity of reflective wall %

From Table 2, when the reflectance of the reflective wall 70 is 100%, the difference in height between the reflective wall and the top surface of the wavelength conversion layer of 20 μm can reduce the viewing angle by 1.2 to 1.3 degrees. The higher the reflectivity of the reflective wall 70, the more pronounced the viewing angle is reduced. The present invention additionally tests that the height difference is reduced by about 2 degrees at a difference of 50 μm, and the difference between the two is about 0.7 to 0.8. In order to achieve the best reduction of the viewing angle of the reflective wall, the structure of the slightly higher reflective wall 70 needs to be adjacent to the top surface of the wavelength conversion layer 50.

In summary, the present invention can be predicted according to the equation obtained by the above linear regression analysis, and surrounds the epitaxial structure 10 and the wavelength conversion layer with a reflective wall corresponding to the reflectance according to the required viewing angle of the product of the LED package structure. 50, you can achieve. This can avoid unnecessary tests.

In the present embodiment, the flip chip 100 is subjected to laser stripping of the grown substrate, or a thinned wafer, comprising an epitaxial structure 10 and a contact pad as an electrode. Due to the thinning of the thickness, the lateral light is sharply reduced and the light shape is more concentrated. The illumination angles required for different applications are used as benchmarks. For example, the projector requires only ±10 degrees of light, the face recognition requires ±40 degrees of light, and the illumination application requires ±60 degrees of light. Taking a blue light wafer as an example, after removing the grown substrate, 3% light intensity (luminous power, I) can be increased within ±10 degrees. The unit of light intensity is candela (cd) = lm / sr (light flux [m] / solid angle Ω [sr] in solid angle)

Taking the packaged white light element as an example, the light intensity after removing the grown substrate is also increased, and the slightly higher reflective wall structure can make the light shape more concentrated. A thinner thickness also contributes to the concentration of the light shape. Compared with reflective walls with different reflectivity, the reflective wall with high reflectivity has a higher light intensity at a small angle, which proves that the reflective wall with high reflectivity can make the light shape more concentrated. According to Table 1 of the first experimental example, the light intensity (%) of the different illumination angles was measured as shown in Table 3 below, the light intensity table of the first experimental example.

Further, according to Table 2 of the second and third experimental examples, the light intensity (%) of different illumination angles was measured as shown in Table 4 below, the light intensity meter.

Further, according to Table 2 of the second and third experimental examples, the light intensity (%) of different illumination angles was measured as shown in Table 5 below, the light intensity meter. Compared with reflective walls with different reflectivity, the reflective wall with high reflectivity has a higher light intensity at a small angle, which proves that the high reflectivity reflective wall can make the light shape more concentrated.

Furthermore, according to the above embodiment, the light intensity area in the integrated viewing angle is the denominator, and the numerator is within ±40 degrees. The larger the ratio, the more concentrated the light shape is within ±40 degrees. It is shown that the structure of the light-emitting diode of the present invention is quite practical.

To quantify the concentration, the light intensity of ±10 degrees is defined as 23~27%, and the light intensity within 10~40 degrees is 50~53%. Therefore, it can be seen that the light-emitting diode package structure of the present invention has a light intensity ratio of ±40 degrees in the light angle and a light intensity area within the viewing angle of more than 0.7; wherein 0 to 10 degrees, the ratio is 0.23 to 0.27; 10~40 degrees, the ratio is 0.50~0.53.

Please refer to FIG. 11 again, which is a top view of the LED package module of the present invention. The present invention is also applicable to a method for forming a light-emitting diode package module. The difference from the above embodiment is that a plurality of flip-chip wafers are placed in an array on a carrier substrate 30, for example, 2x2. Array, but the number is not limited to this. First, the electrodes of the plurality of flip-chip wafers are respectively bonded to corresponding circuit structures on the carrier substrate 30, and then similar to the forming method of the above-mentioned LED package structure, after filling the primer, laser stripping, and rough The step of the epitaxial structure is followed by separately placing the light transmissive wavelength converting layer 50 on the epitaxial structure of the thinned wafer. Finally, a reflective wall 70 is formed to surround each of the wavelength conversion layer 50 and each of the thinned wafers to form a light emitting diode package module 500.

If necessary, the LED package module 500 can be cut along the broken line in FIG. 11 to form a plurality of LED package structures 400 (as shown in FIGS. 8, 8A, and 8B).

The feature and function of the present invention is that by controlling the thickness of the wavelength conversion layer, the overall viewing angle of the LED package structure is changed according to the desired viewing angle, and the calculation obtained by linear regression analysis is used to predict the illumination of the desired viewing angle. Polar body package structure. In addition, by controlling the reflectivity of the reflective wall, the overall viewing angle of the LED package structure can be adjusted. The invention adjusts the viewing angle and thickness of the LED itself to make the elastic space of the optical design larger.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

Claims (11)

A method for forming a light emitting diode package structure that provides a predetermined viewing angle, comprising: placing a flip chip on a carrier substrate; filling a gap between electrodes of the flip chip to support the a flip chip; the laser strips a growth substrate of the flip chip to form a thinned wafer, and exposes an epitaxial structure of the thinned wafer; roughening the exposed thinned wafer An epitaxial structure; providing a viewing angle adjustment structure to the thinned wafer; and selecting a predetermined viewing angle, adjusting the viewing angle adjustment structure according to one of the following formulas to achieve the predetermined viewing angle; Equation 1: Angle of view = 117 ° + 0.05× wavelength conversion layer overall thickness; wherein the viewing angle adjustment structure comprises a wavelength conversion layer, the wavelength conversion layer is attached to the epitaxial structure; wherein the entire thickness of the wavelength conversion layer is from the top surface of the wavelength conversion layer to The thickness of the bottom surface of the epitaxial structure; or the second embodiment: the viewing angle = 141.8-0.2709 × the reflectance % of the reflective wall; wherein the viewing angle adjustment structure comprises a wavelength conversion layer and a reflective wall, The reflective wall encloses the epitaxial structure and the wavelength conversion layer; wherein the reflective wall is equal to the top surface of the wavelength conversion layer; or the third embodiment: the viewing angle=141.9-0.2809×the reflectivity of the reflective wall; wherein the viewing angle adjustment structure The invention comprises a wavelength conversion layer and a reflective wall, the reflective wall coating the epitaxial structure and the wavelength conversion layer; wherein the reflective wall is higher than the top surface of the wavelength conversion layer. A method of forming a light emitting diode package structure according to claim 1, wherein the wavelength conversion layer extends to both sides of the epitaxial structure according to Equation 1, completely covering the Epitaxial structure. The light emitting diode package structure capable of providing a predetermined viewing angle as described in claim 1 a forming method, wherein a width of the wavelength conversion layer is greater than or equal to a width of the epitaxial structure. The method for forming a light emitting diode package structure according to claim 1, wherein the reflective wall exceeds a top surface of the wavelength conversion layer by 10 to 50 μm according to the third formula. The method for forming a light emitting diode package structure according to claim 1, wherein the carrier substrate has a circuit structure, and the electrode of the flip chip is electrically connected to the carrier substrate. The circuit structure. A light emitting diode package structure capable of providing a predetermined viewing angle, which is formed by the method of claim 1. A light emitting diode package structure comprising: a carrier substrate having a circuit structure; a thinned wafer on the carrier substrate, the thinned wafer having an epitaxial structure and a pair of electrodes on a bottom surface thereof The electrode is in contact with the circuit structure; a primer is located in a gap between the electrodes of the thinned wafer to support the thinned wafer, wherein the primer is an opaque material; a wavelength conversion layer Having at least overlying the epitaxial structure of the thinned wafer; and a reflective wall surrounding the wavelength conversion layer and the thinned wafer, wherein the reflectivity of the reflective wall is greater than 70% and higher than The top surface of the wavelength conversion layer is 10 to 50 μm. The light-emitting diode package structure according to claim 7, wherein the ratio of the light intensity of the light-emitting diode structure to the light intensity of ±40 degrees and the light intensity area within the viewing angle is greater than 0.7; ~10 degrees, the ratio is 0.23~0.27; among them, 10~40 degrees, the ratio is 0.50~0.53. Method for forming a light-emitting diode package module capable of providing a predetermined viewing angle, package Included: placing a plurality of flip-chip wafers on a carrier substrate; filling a gap between the electrodes of each of the flip-chip wafers to support the flip chip; laser stripping each of the overlays Forming a thinned wafer of a grown wafer of the crystalline wafer and exposing an epitaxial structure of each of the thinned wafers; roughening the epitaxial structure exposed by each of the thinned wafers; providing a viewing angle Adjusting the structure to each of the thinned wafers; and selecting a predetermined viewing angle, adjusting the viewing angle adjustment structure according to one of the following formulas to achieve the predetermined viewing angle; Equation 1: Angle of view = 117 ° + 0.05 × wavelength conversion layer An overall thickness; wherein the viewing angle adjustment structure includes a wavelength conversion layer, the wavelength conversion layer being attached to the epitaxial structure; wherein the entire thickness of the wavelength conversion layer is from a top surface of the wavelength conversion layer to the epitaxial structure The thickness of the bottom surface; or the second embodiment: the viewing angle = 141.8-0.2709 × the reflectance % of the reflective wall; wherein the viewing angle adjustment structure comprises a wavelength conversion layer and a reflective wall, the reflective wall coating the epitaxial structure and the a wavelength conversion layer; wherein the reflective wall is equal to the top surface of the wavelength conversion layer; or Equation 3: viewing angle = 141.9-0.2809 × reflectance % of the reflective wall; wherein the viewing angle adjustment structure comprises a wavelength conversion layer and a reflective wall, the reflection A wall envelops the epitaxial structure and the wavelength conversion layer; wherein the reflective wall is higher than a top surface of the wavelength conversion layer. A light emitting diode package module includes: a carrier substrate having a circuit structure; a plurality of thinned wafers disposed on the carrier substrate, each of the thinned wafers having an epitaxial structure and a bottom surface thereof a pair of electrodes, the electrodes being in contact with the circuit structure; a primer located in a gap between the electrodes of each of the thinned wafers To support the thinned wafer, wherein the primer is an opaque material; a wavelength conversion layer covering at least the epitaxial structure of each of the thinned wafers; and a reflective wall surrounding each a wavelength conversion layer and each of the thinned wafers, wherein the reflective wall has a reflectance greater than 70% and is higher than the top surface of the wavelength conversion layer by 10 to 50 μm. The light emitting diode package module of claim 10, wherein a width of the wavelength conversion layer is greater than or equal to a width of the epitaxial structure.