BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a schematic diagram of a lead type LED element according to the prior art.
FIG. 2 is a schematic diagram of a chip type LED element according to the prior art.
FIG. 3 to FIG. 6 are schematic diagrams of a method of packaging LEDs according to the present invention.
FIG. 7 is a schematic diagram of another embodiment of a method of packaging LEDs according to the present invention.
FIG. 8 is a flow chart of a method of packaging LEDs according to the present invention.
DETAILED DESCRIPTION
Please refer to FIG. 3 to FIG. 6, which are schematic diagrams of a method of packaging LEDs according to the present invention. As shown in FIG. 3, a plurality of LEDs 52 and corresponding wires are formed on a surface of the substrate 50 that is a semiconductor wafer, a glass substrate, or a quartz substrate. And referring to FIG. 4, a plurality of sealants 54, having individual seal pattern, are formed on the surface of the substrate 50 to surround the LEDs 52, respectively. Then, a transparent substrate 56, a glass substrate or a quartz substrate used for packaging LCOS is laminated on the substrate 50 and covers the LEDs 52 and the sealant 54 to perform a lamination process. The sealant 54 is then exposed under an ultraviolet (UV) light for hardening the sealant 54, so that the transparent substrate 56 is fixed on the substrate 50.
Please refer to FIG. 5, a polarization layer 58 is formed on the surface of a transparent substrate 56 by a deposition method, or a polarization film is glued on the transparent substrate 56 to form the polarization layer 58. As shown in FIG. 6, the substrate 50, the transparent substrate 56, and the polarization layer 58 are cut together along the seal patterns of the sealants surrounding each of the LEDs 52 to separate each LED 52 so as to form a plurality of LED dies and finish the process of packaging the LEDs.
In the present embodiment, the LEDs 52 are discretely set on the surface of the substrate 50. And each of the sealants 54 surrounds each of the LEDs 52, so a diced LED die 60 only comprises a single LED 52. And the diced LED die 60 can be directly set in various circuits or electronic instruments such as pilot lamps, just like the conventional lead type LEDs.
Please refer to FIG. 7. FIG. 7 is a schematic diagram of another embodiment according to the present invention. In the present embodiment, a diced LED element 70 comprises a quartz substrate 72, a glass substrate 74 opposite to the quartz substrate 72, a plurality of LEDs 76 and corresponding wires positioned on the surface of the quartz substrate 72, and a sealant 78 surrounding the LEDs 76, which fix the glass substrate 74 on the quartz substrate 72. The LED element 70 further comprises a polarization layer 80 set on the surface of the glass substrate 74. It should be noted that the LED element 70 comprises a plurality of LEDs 76 that are arranged in an array. Therefore, the LED element 70 can be directly applied to an appliance, such as a LCD, that needs a planar light source. On the other hand, the quartz substrate 72 has a characteristic of being pervious to light, so that the present invention comprises forming a polarization layer 82 on the surface of the quartz substrate 72 before cutting the glass substrate 74 and the quartz substrate 72, and cutting the polarization layer 82 together with the quartz substrate 72. As a result, the LEDs device 72 can be applied to an appliance which needs a double-sided light source.
Taken together, please refer to FIG. 8. FIG. 8 is flow chart of the method of packaging LEDs according to the present invention. The present invention comprises the following steps:
Step 102: Provide a wafer and form a plurality of LEDs and corresponding wires on the surface of the wafer.
Step 104: Form at least a sealant on the wafer surface, the sealant having a seal pattern surrounding the LEDs.
Step 106: Perform a lamination process to make a transparent substrate cover the wafer, the LEDs, and the sealant.
Step 108: Expose the sealant under an ultraviolet (UV) light to harden the sealant and fix the transparent substrate on the wafer.
Step 110: Form a polarization layer on the transparent substrate.
Step 112: Dice the wafer along the seal pattern of the sealant that surrounds each of the LEDs so as to form a plurality of LED dies.
In contrast to the prior art, the present invention utilizes packaging technology of LCOS or CIS to perform the method of packaging LEDs. The present invention utilizes a glass to cover the LEDs, and to set a space for setting the LEDs with a wafer and sealant that does not need to form the base seats or plastic molds of the prior art surrounding the LEDs. So the LED packaging technology of the present invention represents breakthrough advancement. In addition, according to the present invention, a polarization layer is optically formed on the surface of the transparent substrate, and the polarization layer is cut together with LEDs to make the LEDs device produce polarized lights after packaging. This LED meets the demands of polarizing light sources of general appliances. As a result, the packaged LED elements can be directly set on each appliance according to the present invention and further simplify assembly and the manufacturing process, along with lowering the manufacturing cost of each appliance.
Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.
Patent Application
20080009086
