Light-emitting diode display panel with micro lens array
A light-emitting diode (LED) display panel includes a substrate, a driver circuit array on the substrate and including a plurality of pixel driver circuits arranged in an array, an LED array including a plurality of LED dies each being coupled to one of the pixel driver circuits, a micro lens array including a plurality of micro lenses each corresponding to and being arranged over at least one of the LED dies, and an optical spacer formed between the LED array and the micro lens array.
1. A method for fabricating a light-emitting diode (LED) display panel, comprising:
providing a semiconductor epitaxial wafer having a semiconductor epitaxial layer formed on a semiconductor substrate, the semiconductor epitaxial layer including a plurality of LED dies on one side of the semiconductor epitaxial layer;
aligning and bonding the semiconductor epitaxial wafer onto a driver circuit wafer having a plurality of driver circuits, each of the LED dies being bonded to one of the driver circuits;
removing the semiconductor substrate; and
processing the semiconductor epitaxial layer from another side opposite to the LED dies to form a plurality of micro lenses, each of the micro lenses corresponding to and arranged over at least one of the LED dies.
2. The method of claim 1 , wherein processing the semiconductor epitaxial layer includes processing the semiconductor epitaxial layer such that each of the micro lenses corresponds to and is arranged over two or more of the LED dies.
3. The method of claim 1 , wherein removing the semiconductor substrate includes removing the semiconductor substrate by at least one of a laser lift-off process or an etching process.
4. The method of claim 3 , wherein removing the semiconductor substrate by the etching process includes etching the semiconductor substrate by at least one of a wet etching process or a dry etching process.
5. The method of claim 1 , wherein processing the semiconductor epitaxial layer to form the micro lenses includes processing the semiconductor epitaxial layer such that each of the micro lenses is aligned with the corresponding one of the LED dies.
6. The method of claim 1 , wherein processing the semiconductor epitaxial layer to form the micro lenses includes processing the semiconductor epitaxial layer to form the micro lenses that are separated and electrically isolated from each other.
7. The method of claim 1 , further comprising:
processing a portion of the semiconductor epitaxial layer between the micro lenses and the LED dies into a plurality of spacer units that are separated and electrically isolated from each other.