TWI422071B - Package structure of light emitting diode - Google Patents

Description

Light-emitting diode package structure

The present invention relates to a package structure, and more particularly to a package structure of a light emitting diode (LED).

The light-emitting diode is a kind of semiconductor component, and has the advantages of high efficiency, long life, and being difficult to be broken, and the conventional light source cannot be compared with it. At present, it is mostly used in indicator lights, display panels, etc., and is most commonly used in traffic signs and street lighting. With the advent of white light-emitting diodes, light-emitting diodes are regarded as new light sources in the 21st century.

Since the size of the light-emitting diode is small and the switching speed is fast, the light source of the electronic device, such as a mobile phone, a liquid crystal screen, and an LED printer, is gradually replaced. The LED printer uses LED as a light source for imaging. Compared with the traditional laser printer, it has the advantages of small size and fast printing speed. In addition, the LED light source can also be used in a photo-sensitive printer, in which a special optical printer is required to generate light of a specific wavelength, and the optical printer can currently utilize light. The diode array acts as a light source and then uses a lens to transmit light and focus. However, the optical mechanism of the current optical printer head is too complicated, large in size, and easily causes assembly accuracy to be too low, which is not advantageous for mass production.

In the conventional optical printer head, the LED and the driving chip are individually packaged and then integrated into the printed circuit board, so that the volume is large and the manufacturing cost is high. In addition, the light source of the LED uses an optical passive component such as a lens to focus the light. Since part of the light of the LED is scattered to a region other than the lens, the light coupling efficiency is poor. In order to increase the energy of the light source, a higher driving current can be used to drive the LED, but while the driving current is increased, the temperature of the light emitting diode is raised, which causes additional heat dissipation problems and reduces the life of the light emitting diode.

The invention provides a package structure of a light-emitting diode, which integrates the LED directly into the groove of the driving wafer, thereby reducing the overall package volume. A partially transparent mask is disposed above the driving wafer to focus the light emitted by the LED, and the mask can replace the optical passive component to simplify the package structure of the LED and reduce the design cost.

The invention provides a package structure of a light emitting diode, comprising a driving chip, a first light emitting diode element and a masking member. The driving wafer has a first recess, and the first LED component is disposed in the first recess. The mask member has a first light transmissive region, the mask member is disposed on the driving wafer and the first light transmissive region corresponds to the first recess.

In an embodiment of the invention, the mask member and the driving wafer have a gap between 16 micrometers (um) and 20 micrometers (um).

In an embodiment of the invention, the driving chip further has a second recess to provide a second LED component, the mask component further has a second light transmissive region, and the second light transmissive region corresponds to The second groove described above.

In an embodiment of the invention, the first light transmission region comprises a light transmission hole or a light transmissive glass.

In an embodiment of the invention, the package structure of the light emitting diode further includes a printed circuit board for arranging the driving chip, wherein the driving chip is located between the printed circuit board and the mask member, wherein the driving chip Further having at least a uniform through hole, the printed circuit board is electrically connected to the circuit component on the driving wafer via the through hole. Wherein the through-holes are formed by a through-pass twin-hole encapsulation technique.

In an embodiment of the invention, the driving chip has a first surface and a second surface, the first recess is located on the first surface of the driving wafer, the mask member faces the first surface, and the printed circuit board faces the driving The second side of the wafer.

In summary, the package structure of the light-emitting diode of the present invention provides a light-emitting diode element by using a groove for driving the wafer to simplify and reduce the package structure, and the package substrate is omitted. Additionally, the present invention utilizes the micro-holes of the mask to replace the optically passive components to control the amount of light output. Thereby, the package structure of the light-emitting diode of the present invention has the effects of simplifying the package structure, reducing the structure volume, and reducing the design cost.

The above described features and advantages of the present invention will be more apparent from the following description.

FIG. 1 is a schematic diagram of a package structure of a light emitting diode according to an embodiment of the invention. The package structure of the light emitting diode includes a printed circuit board 110, a driving wafer 120, and a mask member 130. The driving chip 120 is disposed between the mask member 130 and the printed circuit board 110. The mask member 130 has a plurality of transparent regions 132. The six transparent regions are exemplified in FIG. 1, but the embodiment is not limited. . The driving wafer 120 has a recess to provide a light emitting diode element, and the light transmitting area 132 on the mask 130 corresponds to a recess, so that light emitted by the LED can be emitted through the light transmitting area 132. In this embodiment, the number of the light-transmissive areas on the mask member 130 can be determined according to design requirements, such as the number of LEDs, and the embodiment is not limited.

Next, please refer to FIG. 2 at the same time. FIG. 2 is a schematic cross-sectional view of the package structure according to the section line AA' of FIG. The drive wafer 120 has a plurality of grooves to respectively provide the light emitting diode elements. Taking the recess 126 as an example, the light emitting diode element 142 is disposed in the recess 126. The light transmissive area 132 on the mask 130 is located directly above the recess 126 to allow the light of the LED body 142 to pass. . It should be noted that the circuit components and recesses of the driving wafer 120 may be formed on the same side of the driving wafer 120, so that the driving wafer 120 may be directly connected to the corresponding light emitting diode element 142 to provide a driving power source. When the driver wafer 120 is provided with LED arrays of different wavelengths (eg, three LED arrays of red, green, and blue), the driver wafer 120 can control different LED arrays to be mixed into a light source of a desired color.

The mask member 130 is formed of, for example, a enamel or glass material, and an area outside the light transmitting region is an opaque region, which can be used to block scattering of light. In the present embodiment, if the mask member 130 is formed of glass, an opaque material (for example, a black paint) may be applied to a region other than the light-transmitting region 132 to prevent light from scattering. If the mask member 130 is formed of a tantalum material, the light transmissive region 132 can be formed by an opening method. When the light transmitting region 132 is an opening, the inner side surface of the opening is a smooth reflecting surface to reduce the energy loss of light. This embodiment does not limit the material of the mask member 130 and the structure of the light transmitting region 132 as long as the light emitted by the LED can pass through the light transmitting region 132. The structure of the remaining light-transmissive regions on the mask member 130 is the same as that of the light-transmitting region 132, and will not be described here.

There is a gap 150 between the mask member 130 and the driving wafer 120. The width H of the gap 150 is determined according to the wavelength of the light to reduce the light diffraction phenomenon, and the width H is, for example, between 16 micrometers (um) and 20 micrometers (um). Between, but this embodiment is not limited. The gap between the mask member 130 and the driving wafer 120 can be adhered by the adhesive material 170 and the size of the gap 120 can be determined. Since there is a gap 150 between the mask member 130 and the drive wafer 120, there is an appropriate distance between the light transmissive region 132 and the recess 126 to reduce the occurrence of diffraction.

The printed circuit board 110 is used to set the drive wafer 120, which is located on the back side of the drive wafer 120. In other words, the mask 130 faces the first side of the drive wafer 120 and the printed circuit board 110 faces the second side of the drive wafer 120. The driving wafer 120 has a plurality of through holes for electrically connecting the circuit elements on the first side of the driving wafer 120 with the printed circuit board 110. Taking the through hole 122 as an example, the printed circuit board 110 can be electrically connected to the circuit components in the driving wafer 120 through the through holes 122 to transmit signals or power. The through holes 122 in the driving wafer 120 are formed, for example, by a through-silicon via packaging technique (Through-Silicon Via, Via). The manner in which the through holes 122 and the recesses 126 are formed may be implemented by a semiconductor process or a microelectromechanical system (MEMS) process, and the embodiment is not limited. After the description of the above embodiments, those skilled in the art should be able to infer other embodiments, which are not described herein.

In the present embodiment, the light emitting diode element 142 is disposed directly in the recess 126 of the driving wafer 120, thereby reducing the package volume. The light transmissive region 132 of the mask member 130 can be used to guide the light of the LED body 142 for imaging on a desired image surface, so that the mask member 130 can be used to replace an optical passive component (such as a lens) in the prior art. Simplify the complexity and design cost of optical modules. The printed circuit board 110 and the circuit in the driving wafer 120 are directly formed by the through-holes 122 formed by the through-silicon via packaging technology for electrical connection. Such a structure can further reduce the volume of the overall package structure and at the same time improve the stability of electrical signal transmission. Moreover, since the mask member 130, the driving wafer 120 and the printed circuit board 110 in the embodiment can be packaged and integrated in a stacked manner, the packaging process and cost can be simplified, and the mass production and application are more favorable.

The package structure of the light-emitting diode of the present invention can be applied to a print head component of an optical printer as a light source, and the drive wafer 120 can be arranged in an array groove according to the resolution required by the print head component. The arrangement of the array of light-emitting diode elements is not limited to the structure of FIGS. 1 and 2. After the description of the above embodiments, those skilled in the art should be able to infer other embodiments, which are not described herein.

In summary, the present invention utilizes a recess to provide a light emitting diode element, and a mask member is provided instead of the optical passive element. Therefore, the package structure of the light emitting diode of the present invention has a reduced volume, simplifies the packaging process, and reduces Cost and other advantages.

Although the preferred embodiments of the present invention have been disclosed as above, the present invention is not limited to the above-described embodiments, and any one of ordinary skill in the art can make some modifications without departing from the scope of the present invention. The scope of protection of the present invention should be determined by the scope of the appended claims.

110. . . A printed circuit board

120. . . Driver chip

122. . . Through hole

126. . . Groove

130. . . Mask

132. . . Light transmission area

142. . . Light-emitting diode component

150. . . gap

170. . . Adhesive material

AA’. . . Section line

H. . . width

FIG. 1 is a schematic diagram of a package structure of a light emitting diode according to an embodiment of the invention.

Fig. 2 is a schematic cross-sectional view showing a package structure according to the section line AA' of Fig. 1.

110. . . A printed circuit board

120. . . Driver chip

122. . . Through hole

126. . . Groove

130. . . Mask

132. . . Light transmission area

142. . . Light-emitting diode component

150. . . gap

170. . . Adhesive material

H. . . width

Claims (9)

A package structure of a light emitting diode includes: a driving wafer having a first groove; a first light emitting diode element disposed in the first groove; and a mask member having a first light transmitting region, the mask member is disposed on the driving wafer and the first light transmitting region corresponds to the first groove. The package structure of the light-emitting diode according to claim 1, wherein the mask has a gap with the drive wafer. The package structure of the light-emitting diode according to claim 2, wherein the gap has a width of between 16 micrometers and 20 micrometers. The package structure of the light-emitting diode according to claim 1, wherein the driving chip further has a second recess to provide a second light-emitting diode element, and the mask has a second transparent The light zone, the second light transmission zone corresponds to the second groove. The package structure of the light-emitting diode according to claim 1, wherein the first light-transmissive region comprises a light-transmitting hole. The package structure of the light-emitting diode according to claim 1, further comprising a printed circuit board for arranging the drive chip, the drive chip being located between the printed circuit board and the mask member, wherein the The driving wafer further has at least a uniform through hole, and the printed circuit board is electrically connected to the circuit elements on the driving wafer via the through holes. The package structure of the light-emitting diode according to claim 6, wherein the driving wafer has a first surface and a second surface, the first groove is located on the first surface of the driving wafer, the shielding The cover member faces the first side, and the printed circuit board faces the second side of the drive wafer. The package structure of the light-emitting diode according to claim 6, wherein the through holes are formed by a through-pass twinned package technique. The package structure of the light-emitting diode according to claim 1, wherein the first light-transmissive region is a light-transmissive glass.