Using MEMS fabrication incorporating into LED device mounting and assembly
LED chip packaging assembly that facilitates an integrated method for mounting LED chips as a group to be pre-wired to be electrically connected to each other through a pattern of extendable metal wiring lines is provided. LED chips which are electrically connected to each other through extendable metal wiring lines, replace pick and place mounting and the wire bonding processes of the LED chips, respectively. Wafer level MEMS technology is utilized to form parallel wiring lines suspended and connected to various contact pads. Bonding wires connecting the LED chips are made into horizontally arranged extendable metal wiring lines which can be in a spring shape, and allowing for expanding and contracting of the distance between the connected LED chips. A tape is further provided to be bonded to the LED chips, and extended in size to enlarge distance between the LED chips to exceed the one or more prearranged distances.
1. A light-emitting device assembly, comprising:
a plurality of LED chips, each LED chip comprising a plurality of bonding pads for power input and output;
a first metal seed layer and a second metal seed layer, which are arranged on a same side of one of the plurality of the LED chips and formed on a same horizontal plane; and
a plurality of metal lines physically and electrically connecting the plurality of LED chips via the plurality of bonding pads of each LED chip;
wherein each metal line is formed in a planar structure on a virtual plane which is substantially parallel to a bonding surface of the plurality of bonding pads,
wherein the plurality of bonding pads and the plurality of metal lines are arranged on a same side of each LED chip, and
wherein the plurality of LED chips are connected with each other by the plurality of metal lines in a configuration that the plurality of LED chips are movable in two orthogonal directions.
2. The light-emitting device assembly as claimed in claim 1 , further comprising a tape bonded to the LED chips, wherein the LED chips are arranged at one or more prearranged distances from one another, and the tape is able to extend to enlarge the one or more prearranged distances.
3. The light-emitting device assembly as claimed in claim 1 , wherein a thickness of one of the metal lines is between 0 microns to 100 microns.
4. The light-emitting device assembly as claimed in claim 1 , further comprising:
a substrate, the substrate comprising a plurality of pieces thereof, wherein each piece of the substrate holds at least one LED chip, a distance between adjacent pieces of the substrate is extendable so that the distance between the adjacent LED chips thereon is capable to be increased to a preset width.
5. The light-emitting device assembly as claimed in claim 1 , further comprising a substrate, wherein the substrate is selected from a group consisting of an expanding table, a final substrate of a chip-on-glass (COG) type or chip-on-board (COB) type substrate, a plurality of scribed substrate pieces, and a plurality of transparent substrate pieces, wherein the LED chips are mounted on the substrate.
6. The light-emitting device assembly, as claimed in claim 5 , wherein the metal lines are suspended between the substrate and the LED chips.
7. The light-emitting device assembly as claimed in claim 1 , wherein one of the metal line in a contracted state has a structure of a spring.
8. The light-emitting device assembly, as claimed in claim 1 , wherein the second metal seed layer is separated from the first metal seed layer.
9. A light-emitting device assembly, comprising:
an LED chip having a top surface, a bottom surface, and a side surface arranged between the top surface and the bottom surface;
a first electrode with a first side wall, and a second electrode with a second side wall, both formed on the top surface of the LED chip without extending over the side surface of the LED chip;
a first metal seed layer formed on the top surface;
a second metal seed layer formed on the top surface and separated from the first metal seed layer, the first metal seed layer and the second metal seed layer being formed on a same horizontal plane; and
a first metal line formed on the first electrode in a configuration of being extendable on a virtual surface parallel with the top surface or the bottom surface of the LED chip, and comprising a portion which is extended outside the first side wall of the first electrode and physically separated from the top surface of the LED chip by a gap.
10. The light-emitting device assembly as claimed in claim 9 , wherein the portion of the first metal line is overlapped with the LED chip in a cross-sectional view.
11. The light-emitting device assembly, as claimed in claim 9 , further comprising an expanding table on the top surface.
12. The light-emitting device assembly, as claimed in claim 11 , wherein the portion of the first metal line is suspended between the expanding table and the LED chip.
13. The light-emitting device assembly, as claimed in claim 9 , wherein the first metal seed layer and the second metal seed layer are formed between the LED chip and the first metal line in a cross-sectional view.
14. The light-emitting device assembly, as claimed in claim 9 , further comprising a second metal line, wherein the second metal line has a part extended outside the second side wall of the second electrode and physically separated from the top surface of the LED chip by a distance.
15. The light-emitting device assembly, as claimed in claim 14 , wherein the first metal line is connected to the first electrode, and the second metal line is connected to the second electrode.