How LEDs are Made
This is a sheet of LED dies. YunSun buys their dies from a high quality Taiwanese company. That's my thumb next to 4,000 dies. The cost for the sheet is roughly 80RMB or $12.50.
Each sheet has the batch characteristics listed in the corner. The dies on this particular sheet have a wavelength of ~519nm or right on the edge between green and cyan blue. Three thin sheets containing 12,000 LEDs soon to be hatched!
The process starts with punched metal lead frames. Each one of these frames has the basic structure for 20 LEDs. Shown above is about 15 frames or 300 LEDs.