Introduction
[Dr. Semiconductor] produced gallium nitride (GaN)-based transparent LED chips and connected them to a printed circuit board.
Developments
To establish contact with the n-type layer, the researcher broke down the GaN using a 355-nm ultraviolet laser and cleaned it with potassium hydroxide; nickel, silver, and titanium contacts were formed using a photoresist mask and sputtering.
The researcher divided the blue-light-emitting LEDs into individual chips using a laser and soldered the chip by melting the indium bumps on the circuit board.
Details
The researcher then mixed cerium-doped yttrium aluminum garnet phosphor with transparent silicone and applied it over the LED. The combination of the yellow light emitted by the phosphor and the blue light appeared white to the human eye.