What does the LED chip manufacturing process include？

1. Photolithography is the key to precise patterning in chip manufacturing. Through photolithography, the designed chip circuit pattern can be transferred to the epitaxial wafer. For example, photoresist is irradiated with ultraviolet light, and after exposure, development and other steps, precise electrodes, active areas and other structures are formed on the chip. The precision of lithography can reach the nanometer level, which is crucial for manufacturing high-performance miniaturized LED chips.

2. Etching processes are used to remove unwanted parts of the material. For example, through plasma etching, the semiconductor material exposed after lithography can be removed to form a specific structure of the chip, such as the table structure, etc., in order to realize the functions of current limitation and light extraction inside the chip.

3. Doping is an important step in changing the electrical properties of semiconductors. Through ion implantation or thermal diffusion and other methods, specific impurity atoms (such as silicon, magnesium, etc.) into the epitaxial layer of a specific region to change its electrical conductivity, the formation of P-type and N-type semiconductor region, so as to realize the LED chip light-emitting function. For example, magnesium (Mg) is commonly used as a P-type dopant in gallium nitride-based LEDs.