Patent Application
20240006557
This application claims priority to Taiwan Application Serial Number 111124310 filed Jun. 29, 2022, which is herein incorporated by reference.
The present disclosure relates to a circuit board structure, a testing and packaging method, and a pixel package. More particularly, the present disclosure relates to an LED circuit board structure, an LED testing and packaging method, and an LED pixel package.
With the popularization of personal display devices, the miniaturization of LED (light emitting diode) structures has become a trend in the industry. As the sizes of the LEDs scale down, the sizes of the LED pixel packages are reduced accordingly. To ensure the yield rate, LED pixel packages need to be tested. In the conventional LED pixel packaging and testing technology, the LED pixel packages are tested one by one after sealing. However, the small sizes and large quantity of LED pixel packages make the measurements difficult and time-consuming. In addition, if a defect is found after sealing, the entire LED pixel package has to be discarded, resulting in a waste of cost. If there is an integrated circuit chip disposed in the LED pixel package for driving the LEDs, it becomes more difficult to test after packaging. Therefore, to improve the testing efficiency of the LED pixel package and to save the cost are the goals to be achieved in the related field.
According to one aspect of the present disclosure, an LED circuit board structure includes a plurality of first color LEDs, a plurality of second color LEDs, a plurality of third color LEDs, a plurality of integrated circuit chips, a carrier board, a plurality of first P-type pads, a plurality of second P-type pads, a plurality of third P-type pads, a plurality of first color pads, a plurality of second color pads, a plurality of third color pads, a plurality of first testing wires and a plurality of first connecting wires. Each of the first color LEDs includes a first P-type electrode and a first N-type electrode, each of the second color LEDs includes a second P-type electrode and a second N-type electrode, and each of the third color LEDs includes a third P-type electrode and a third N-type electrode. Each of the integrated circuit chips electrically connects each of the first color LEDs, each of the second color LEDs and each of the third color LEDs. The carrier board includes a carrying surface and a bottom surface opposite to each other. The carrying surface includes a plurality of pixel-front-side-pattern regions disposed in intervals. The bottom surface includes a plurality of pixel-back-side-pattern regions respectively corresponding to the pixel-front-side-pattern regions. One of the first color LEDs, one of the second color LEDs, one of the third color LEDs and one of the integrated circuit chips are disposed in one of the pixel-front-side-pattern regions. The first P-type pads are located at the carrying surface of the carrier board, and one of the first P-type pads is disposed at one of the pixel-front-side-pattern regions for mounting one of the first P-type electrodes. The second P-type pads are located at the carrying surface of the carrier board, and one of the second P-type pads is disposed at one of the pixel-front-side-pattern regions for mounting one of the second P-type electrodes. The third P-type pads are located at the carrying surface of the carrier board, and one of the third P-type pads is disposed at one of the pixel-front-side-pattern regions for mounting one of the third P-type electrodes. The first color pads are located at the carrying surface of the carrier board. One of the first color pads is disposed at one of the pixel-front-side-pattern regions for mounting a first pin of the integrated circuit chip that is disposed at the same pixel-front-side-pattern region, and for electrically connecting the first P-type pad that is disposed at the same pixel-front-side-pattern region. The second color pads are located at the carrying surface of the carrier board. One of the second color pads is disposed at one of the pixel-front-side-pattern regions for mounting a second pin of the integrated circuit chip that is disposed at the same pixel-front-side-pattern region, and for electrically connecting the second P-type pad that is disposed at the same pixel-front-side-pattern region. The third color pads are located at the carrying surface of the carrier board. One of the third color pads is disposed at one of the pixel-front-side-pattern regions for mounting a third pin of the integrated circuit chip that is disposed at the same pixel-front-side-pattern region, and for electrically connecting the third P-type pad that is disposed at the same pixel-front-side-pattern region. The first testing wires are located at the carrying surface of the carrier board, and one of the first testing wires is disposed at one of the pixel-front-side-pattern regions and extends from the first P-type pad or the first color pad that is disposed at the same pixel-front-side-pattern region. Each of the first connecting wires electrically connects two of the first testing wires of adjacent two of the pixel-front-side-pattern regions in parallel.
According to another aspect of the present disclosure, an LED testing and packaging method includes an integrated circuit chip mounting step, an LED mounting step, an LED testing step and a carrier board cutting step. In the integrated circuit chip mounting step, a plurality of integrated circuit chips are mounted to a circuit board. In the LED mounting step, a plurality of first color LEDs, a plurality of second color LEDs and a plurality of third color LEDs are mounted to a circuit board. The circuit board includes a carrier board, a plurality of first P-type pads, a plurality of first color pads, a plurality of first testing wires, a plurality of first connecting wires and a plurality of cutting lanes. The carrier board includes a carrying surface and a bottom surface opposite to each other. The carrying surface includes a plurality of pixel-front-side-pattern regions disposed in intervals. The bottom surface includes a plurality of pixel-back-side-pattern regions respectively corresponding to the pixel-front-side-pattern regions. The first P-type pads are located at the carrying surface of the carrier board, and one of the first P-type pads is disposed at one of the pixel-front-side-pattern regions for mounting one of the first color LEDs. The first color pads are located at the carrying surface of the carrier board. One of the first color pads is disposed at one of the pixel-front-side-pattern regions for mounting a first pin of one of the integrated circuit chips, and for electrically connecting the first P-type pads that is disposed at the same pixel-front-side-pattern region. The first testing wires are located at the carrying surface of the carrier board. One of the first testing wires is disposed at one of the pixel-front-side-pattern regions and extends from the first P-type pad or the first color pad that is disposed at the same pixel-front-side-pattern region. Each of the first connecting wires electrically connects two of the first testing wires of adjacent two of the pixel-front-side-pattern regions in parallel. The cutting lanes are located at the carrier board and are located between each of the pixel-front-side-pattern regions. A part of each of the first connecting wires is located at the cutting lanes. In the LED testing step, the first connecting wires are powered to test each of the first color LEDs. An electric current flows from one of the first connecting wires into one of the first testing wires and flows into one of the first color LEDs through one of the first P-type pads or through one of the first color pads and one of the first P-type pads. In carrier board cutting step, the carrier board is cut along the cutting lanes such that the pixel-front-side-pattern regions separate from each other and the first connecting wires or the first testing wires are cutting off to form a plurality of pixels to be packaged.
According to still another aspect of the present disclosure, an LED pixel package includes a carrier board, a first color LED, a second color LED, a third color LED, an integrated circuit chip, a sealing layer and a first wire set. The carrier board includes a carrying surface. The first color LED is disposed on the carrying surface. The second color LED is disposed on the carrying surface. The third color LED is disposed on the carrying surface. The integrated circuit chip is disposed on the carrying surface and electrically connects the first color LED, the second color LED and the third color LED. The sealing layer covers the first color LED, the second color LED, the third color LED and the integrated circuit chip. The first wire set is disposed at the carrying surface and electrically connects the first color LED and the integrated circuit chip. A part of the first wire set extends from the first color LED or the integrated circuit chip to an edge of the carrier board. A top surface of the part is higher than the carrying surface of the carrier board to form a metal break surface at the edge.
The present disclosure can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows:
The carrier board 1100 includes a carrying surface 1110 and a bottom surface 1120 opposite to each other. The carrying surface 1110 includes pixel-front-side-pattern regions 1111 disposed in intervals. The bottom surface 1120 includes pixel-back-side-pattern regions 1121 respectively correspond to the pixel-front-side-pattern regions 1111. One first color LED 1210, one second color LED 1310, one third color LED 1410 and one integrated circuit chip 1510 are disposed in one of the pixel-front-side-pattern regions 1111.
Each of the first color LEDs 1210 includes a first P-type electrode and a first N-type electrode, each of the second color LEDs 1310 includes a second P-type electrode and a second N-type electrode, and each of the third color LEDs 1410 includes a third P-type electrode and a third N-type electrode. Each of the integrated circuit chips 1510 electrically connects each of the first color LEDs 1210, each of the second color LEDs 1310 and each of the third color LEDs 1410. The first P-type pads 1220 are located at the carrying surface 1110 of the carrier board 1100, and one of the first P-type pads 1220 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting one of the first P-type electrodes. The second P-type pads 1320 are located at the carrying surface 1110 of the carrier board 1100, and one of the second P-type pads 1320 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting one of the second P-type electrodes. The third P-type pads 1420 are located at the carrying surface 1110 of the carrier board 1100, and one of the third P-type pads 1420 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting one of the third P-type electrodes. The first N-type pads 1230 are located at the carrying surface 1110 of the carrier board 1100, and one of the first N-type pads 1230 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting one of the first N-type electrodes. The second N-type pads 1330 are located at the carrying surface 1110 of the carrier board 1100, and one of the second N-type pads 1330 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting one of the second N-type electrodes. The third N-type pads 1430 are located at the carrying surface 1110 of the carrier board 1100, and one of the third N-type pads 1430 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting one of the third N-type electrodes.
In this embodiment, each of the first color LEDs 1210, the second color LEDs 1310 and the third color LEDs 1410 has a vertical chip structure. In other embodiments, each of the first color LEDs 1210, the second color LEDs 1310 and the third color LEDs 1410 can have a flip-chip structure or other chip structures. For the first color LED 1210 shown in
The first color pads 1520 are located at the carrying surface 1110 of the carrier board 1100. One of the first color pads 1520 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting a first pin of one of the integrated circuit chips 1510, and the one of the first color pads 1520 electrically connects the first P-type pad 1220 that is disposed at the same pixel-front-side-pattern region 1111. The second color pads 1530 are located at the carrying surface 1110 of the carrier board 1100. One of the second color pads 1530 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting a second pin of one of the integrated circuit chips 1510, and the one of the second color pads 1530 electrically connects the second P-type pad 1320 that is disposed at the same pixel-front-side-pattern region 1111. The third color pads 1540 are located at the carrying surface 1110 of the carrier board 1100. One of the third color pads 1540 is disposed at one of the pixel-front-side-pattern regions 1111 for mounting a third pin of one of the integrated circuit chips 1510, and the one of the third color pads 1540 electrically connects the third P-type pad 1420 that is disposed at the same pixel-front-side-pattern region 1111.
The first testing wires 1610 are located at the carrying surface 1110 of the carrier board 1100, and one of the first testing wires 1610 is disposed at one of the pixel-front-side-pattern regions 1111 and extends from one of the first P-type pads 1220 or one of the first color pads 1520 that is disposed at the same pixel-front-side-pattern region 1111. Each of the first connecting wires 1620 electrically connects two of the first testing wires 1610 of adjacent two of the pixel-front-side-pattern regions 1111 in parallel.
The LED circuit board structure 1000 further includes back electrode pads 2210, 2220, 2230, 2240, 2250. The back electrode pads 2210 electrically connect the third N-type pads 1430 and the integrated circuit chip 1510. The back electrode pads 2220, 2230, 2240, 2250 electrically connect the integrated circuit chip 1510. The back electrode pads 2210, 2220, 2230, 2240, 2250 are configured to connect with a processor or a controller for driving the integrated circuit chip 1510 to control the first color LED 1210, the second color LED 1310 and the third color LED 1410 after packaging. Therefore, the first color LED 1210, the second color LED 1310 and the third color LED 1410 cannot be tested directly after cutting and packaging.
Through the structure of the first testing wires 1610 and the first connecting wires 1620, electric currents can by-pass the integrated circuit chips 1510 and be directly provided to the first color LEDs 1210 before the carrier board 1100 is cut. In other words, if the first testing wire 1610 extends from the first P-type pad 1220, an electric current can be allowed to flow through the first connecting wire 1620 into the first testing wire 1610 and thus flow through the first P-type pad 1220 into the first color LED 1210 during testing; if the first testing wire 1610 extends from the first color pad 1520, an electric current can be allowed to flow through the first connecting wire 1620 into the first testing wire 1610 and thus flow through the first color pad 1520 and the first P-type pad 1220 into the first color LED 1210 during testing. Furthermore, the first color LEDs 1210 in adjacent pixel-front-side-pattern regions 1111 can be connected in parallel and an electric voltage can thus be applied on multiple first color LEDs 1210 in the LED circuit board structure 1000. Since the first color LEDs 1210 of adjacent pixel-front-side-pattern regions 1111 are connected in parallel, when one of the first color LEDs 1210 fails or not be completely mounted while other first color LEDs 1210 are normal, only the failed or not-completely-mounted first color LED 1210 fails to illuminate, and other first color LEDs 1210 still illuminate. Therefore, the efficiency of testing the first color LEDs 1210 is improved.
Further, the LED circuit board structure 1000 can further include a plurality of second testing wires 1710, a plurality of second connecting wires 1720, a plurality of third testing wires 1810 and a plurality of third connecting wires 1820. The second testing wires 1710 are located at the bottom surface 1120 of the carrier board 1100. One of the second testing wires 1710 is disposed at one of the pixel-back-side-pattern regions 1121 and electrically connects the second P-type pad 1320 or the second color pad 1530 that is disposed at the pixel-front-side-pattern region 1111 where the one of the pixel-back-side-pattern 1121 corresponds. For example, in
Similar to the first testing wires 1610 and the first connecting wires 1620, through the structures of the second testing wires 1710, the second connecting wires 1720, the third testing wires 1810 and the third connecting wires 1820, the efficiency of testing the second color LEDs 1310 and the third color LEDs 1410 can be improved.
In
The wiring layout of the LED circuit board structure 1000 is further illustrated bellow.
Therefore, fixtures having multiple probes can be clipped on the edge of the carrier board 1100, and each probe can respectively electrically connect one of first data wires 1630, second data wires 1730, third data wire 1830 and fourth data wire 1920. Signals can be input through the probes to the first color LEDs 1210, the second color LEDs 1310, and the third color LEDs 1410. For example, input signals can be configured to be simultaneously applied on the first color LEDs 1210 of the same row along the first direction X. If there are first color LEDs 1210 that do not illuminate, then those first color LEDs 1210 can be determined to be abnormal, and can be replaced or be re-mounted to confirm accordingly. Otherwise, input signals can be configured to be applied on the first color LEDs 1210 of the same row by turns. Using an automated optical inspection system, the optical image of the LED circuit board structure 1000 corresponding to each moment that an electric voltage being applied to each first color LED 1210 can be captured, the analysis can then be carried out to determine whether the nth first color LED 1210 illuminates when the electric voltage applies on, and more precise results can be achieved. Similar methods can be used to test the second color LEDs 1310 and the third color LEDs 1410.
In
To achieve the above benefits, the line widths and the line distances of the wires of the LED circuit board structure 1000 can be adjusted according to the demands. In this embodiment, the line widths of each first data wire 1630, each second data wire 1730, each third data wire 1830 and each fourth data wire 1920 are in a range of 25 μm to 40 μm, and the line distance between one of the first data wires 1630 and one of the fourth data wires 1920 adjacent thereto, and the line distance of one of the second data wires 1730 and one of the third data wires 1830 adjacent thereto are in a range of 40 μm to 50 μm. In the above ranges, normal operations of the LED circuit board structure 1000 under operating currents can be ensured, and the transverse electric field between the wires can be avoided to avoid sudden short. Meanwhile, appropriate line widths and line distances allow the first data wires 1630, the second data wires 1730, the third data wires 1830 and the fourth data wires 1920 to be accommodated in the cutting lanes 2100 for the cutting process. Since the first data wires 1630, the second data wires 1730, the third data wires 1830 and the fourth data wires 1920 do not occupy additional spaces, the package quantities made out of a unit carrier board 1100 can be retained, and the best utility rate of the carrier board 1100 can be achieved.
Please refer to
In the LED testing step 303, the first connecting wires 1620 are powered to test each of the first color LEDs 4210. The detail flow diagram of the LED testing step 303 is shown in
In carrier board cutting step 304, the carrier board 1100 is cut along the cutting lanes 2100 such that the pixel-front-side-pattern regions 1111 separate from each other and the first connecting wires 1620 or the first testing wires 1610 are cutting off to form a plurality of pixels to be packaged. In
In the LED testing packaging method, through executing the pixel packaging step 305 after the LED testing step 303, abnormal first color LEDs 1210, second color LEDs 1310 and third color LEDs 1410 can be found out and replaced or re-mounted timely. Therefore, discarding normal first color LEDs 1210, second color LEDs 1310 or third color LEDs 1410 that are sealed with the abnormal first color LEDs 1210, second color LEDs 1310 or third color LEDs 1410 can be avoided, and cost can be saved.
In other words, as shown in
Although the present disclosure has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 111124310 | Jun 2022 | TW | national |
