Increased light extraction from a nitride LED
AssigneeGELcore, LLC
InventorsMichael J. Sackrison, Hari S. Venugopalan, Xiang Gao
Life of this patent
Estimating the term…
Abstract
In a method for fabricating a flip-chip light emitting diode device, a submount wafer is populated with a plurality of the light emitting diode dies. Each device die is flip-chip bonded to the submount. Subsequent to the flip-chip bonding, a growth substrate is removed. The entire submount is immersed in the etchant solution, exposed to the light for a prespecified period of time, removed from the solution, dried and diced into a plurality of LEDs. The LEDs are immediately packaged without any further processing.
Claims14
A method for fabricating a light emitting device comprising:
- depositing epitaxial layers on a growth substrate to produce an epitaxial wafer;
- fabricating a plurality of light emitting diode devices with a lateral current flow geometry on the epitaxial wafer;
- dicing the epitaxial wafer to generate a plurality of light emitting dies;
- flip chip bonding at least one electrode of one or more die to at least one bonding pad of a mount;
- subsequent to bonding of the dies, removing the growth substrate to expose an epitaxial layer;
- and
- roughening the epitaxial layer by electrode-less photochemical etching.
A method for fabricating a Group III Nitride semiconductor lateral current light emitting diode device comprising:
- depositing epitaxial layers on a growth substrate to produce an epitaxial wafer;
- fabricating a plurality of light emitting diode devices on the epitaxial wafer;
- dicing the epitaxial wafer to generate a plurality of light emitting diode device dies, each including laterally disposed first and second electrodes;
- flip chip bonding the device dies to a mount, the flip chip bonding including securing the device dies to the mount by bonding the first and second electrodes of each device die to corresponding bonding pads of the mount;
- subsequent to the flip chip bonding of the device dies, removing the growth substrate to expose an epitaxial layer;
- roughening the exposed epitaxial layer being exposed by the substrate removal by electrode-less photochemical etching without applying a bias, including:
- immersing the mount, carrying the device dies, in a chemical solution for a prespecified time period, and
- concurrently illuminating the immersed exposed epitaxial layer with a light source;
- removing the mount carrying the device dies from the chemical solution;
- rinsing the mount carrying the device dies;
- drying the mount carrying the device dies;
- dicing the mount to generate a plurality of light emitting diode chips;
- and
- packaging the light emitting diode chips.
Dependencies are inferred from the claim text.