Industrial Technology Research Institute

Chien-Cheng Yang

Jing-Yao Chang

Chao-Kai Hsu

Zhi-Cheng Hsiao

Gen-Wen Hsieh

Ra-Min Tain

Shyi-Ching Liau

A substrate-free light emitting diode (LED) including an epitaxy layer, a conductive supporting layer, and a first contact pad is provided. The epitaxy layer includes a first type doped semiconductor layer, a light emitting layer, and a second type doped semiconductor layer. The light emitting layer is disposed on the first type doped semiconductor layer, and a portion of the first type doped semiconductor layer is exposed. The second type doped semiconductor layer and the conductive supporting layer are sequentially disposed on the second type doped semiconductor layer. The first contact pad is disposed on the exposed first type doped semiconductor layer and electrically connected thereto. The first contact pad and the conductive supporting layer serving as an electrode are disposed on the same side of the epitaxy layer to avoid the light shielding effects of the electrode to improve the front light emitting efficiency of the LED.

Substrate-free light emitting diode

The invention provides a method of manufacturing a bendable solid state lighting (SSL). A first metal layer and a second metal layer with a predetermined circuit layout pattern and structure region pattern are first deposited on both sides of a flexible substrate respectively, where a plurality of bonding pads is formed on the structure regions in the structure region pattern and is used for being electrically connected to the first metal layer. A plurality of LED dies is arranged on the structure regions in an array, and the LED dies are bonded with the corresponding bonding pads, such that the LED dies are conducted with current via the circuit layout of the first metal layer on the flexible substrate, so as to form a planar light source.

Method of manufacturing bendable solid state lighting

Fabrication method of substrate-free light emitting diode

A bendable LED planar light source structure, a flexible substrate therefore, and a manufacturing method thereof are provided. The flexible substrate has metal layers on both sides, where the metal layer on one side has a circuit layout, and the metal layer on the other side has a pattern structure or a whole metal coating with reflecting and scattering characteristics. Meanwhile, bonding pads are provided on the same side or opposite side as the metal layer with the circuit layout, and an array of LED dies is bonded with the bonding pads through wire bonding or flip chip bonding, such that the LED dies are conducted with current through the circuit layout on the flexible substrate, so as to form a planar light source.

Bendable solid state planar light source structure

Disclosed is a lighting device with flipped side-structure of LEDs, which allows emitted lights to travel in parallel with the mounting surface. Single or plural LED chips are mounted on a substrate with their side surfaces facing the substrate surface. The lighting device can be further combined with optical protrusions on the substrate to form a light module for reflecting and mixing lights emitted from the LED chips. It does not require a conventional wire bonding process. The packaging structure also resolves the heat dissipation problem of the LEDs. Electrostatic discharge protection circuits can be included in the light module if desired. The invention achieves good uniformity and high intensity of the combined lights with desired chromaticity.

Growing community of inventors

Taipei County, Taiwan

Chien-Cheng Yang