LED is an important part of its LED epitaxial wafer, let's learn the general process.

 

LED epitaxial wafer process is as follows:

 

Substrate structure design - buffer layer growth - n-type GaN layer - birth - p-type GaN multiple quantum well light emitting layer layer growth - annealing - detection (fluorescent light, x-rays) - epitaxial wafer

 

Epitaxial wafer - design, processing mask template - lithography - ion etching - N type electrode (coating, annealing, etching) - P type electrode (coating, annealing, etching) - scribing - chip sorting, grading

 

Introduced as follows:

 

Fixed: the fixed in a single crystal silicon rod processing stage.

 

Slice: cut monocrystalline silicon rod into a thin wafers with precise geometry size. The process of silicon powder with water spray, and silicon slag produced wastewater.

 

Annealing: double location after nitrogen purging thermal oxidation furnace, using infrared heating to 300 ~ 500 ℃, the surface of silicon and oxygen reaction, make the silicon wafer surface form a protective layer of silicon dioxide.

 

Chamfering: will be finishing annealing silicon into circular arc form, prevent the silicon breaks and lattice defects, increase of epitaxial layer and flatness of the photoresist layer. The process of silicon powder with water spray, and silicon slag produced wastewater.

 

Step detection: to ensure the specifications and quality of silicon wafer, to its for testing. Here will produce waste.

 

Grinding: use a tablet to remove slices and grinding wheel grinding made kerf and surface damage layer, effectively improve the curvature of the monocrystalline silicon slice, flatness and parallelism, reach a of the specifications of the polishing process can handle. This process produces waste grinding tablets.

 

To clean: through the role of the dissolved organic solvent, combined with ultrasonic cleaning technology to remove organic impurities on the surface of the wafer. This process produces organic waste gas and waste organic solvent.

 

RCA cleaning: through multi-channel cleaning to remove particulate matter and metal ions on the surface of the wafer.