Micro-device with strengthened connecting layers
A micro device includes a securing layer, a plurality of micro device units that are separated from each other and that are spaced apart from the securing layer, and a connecting layer that interconnects the micro device units in at least one group of two or more and that is connected to the securing layer so that the micro device units are connected to the securing layer through the connecting layer. A method of making the micro device is also provided.
1. A micro device, comprising:
a securing layer;
a plurality of micro device units that are separated from each other and that are spaced apart from said securing layer in a laminating direction, each of said micro device units having a plurality of layers disposed on one another along the laminating direction, being surrounded by said securing layer, and cooperating with said securing layer to define a cavity therebetween, the cavity formed squarely between the securing layer and each of the micro device units in a lateral direction or each of the laminating and lateral directions; and
a connecting layer that directly interconnects said micro device units in at least one group of two or more and that is connected to said securing layer so that said micro device units are connected to said securing layer through said connecting layer,
wherein said connecting layer includes a plurality of connecting portions, each of which directly interconnects said micro device units of a respective one of the groups of said micro device units in an extending direction traverse to the laminating direction, each of said connecting portions being formed integrally with and extending from at least one of said layers of each of said micro device units in the respective one of the groups, said connecting layer being made of one of a gallium phosphide based material and a gallium nitride based material, and
wherein said cavities are formed by removing a sacrificial layer in direct contact with said micro device units and said securing layer.
2. The micro device as claimed in claim 1 , wherein each of said connecting portions of said connecting layer has a thickness in the laminating direction that is smaller than a thickness of said at least one of said layers of each of said micro device units in the respective one of the groups.
3. The micro device as claimed in claim 1 , wherein a length of each of said connecting portions of said connecting layer between two adjacent ones of said micro device units in the respective one of the groups is larger than ½ of a minimum distance between said two adjacent ones of said micro device units.
4. The micro device as claimed in claim 1 , wherein each of said connecting portions of said connecting layer has one of a striped-shape and a block-shape.
5. The micro device as claimed in claim 1 , wherein each of said micro device units is an aluminum gallium indium phosphide (AlGaInP) based LED and includes a window layer, said connecting layer being formed integrally with and extends from said window layers of said micro device units, said connecting layer having a thickness smaller than said window layers of said micro device units.
6. The micro device as claimed in claim 1 , wherein said connecting layer has a thickness of 10 nm to 500 nm.
7. The micro device as claimed in claim 1 , wherein said securing layer and said connecting layer has a contact area, said connecting layer having an area parallel to and larger than said contact area.
8. The micro device as claimed in claim 1 , wherein, in an extension direction of said connecting layer, said cavity has a width larger than a width of a respective one of said micro device unit.