In recent years

Patterned Sapphire Substrate (PSS) has become a research hotspot of GaN-based Light Emitting Diode (LED)

for the two significant advantages this technology has embraced:it can not only reduce the defects and dislocation density of GaN epitaxial film

but also significantly improve the Light Extraction Efficiency (LEE) of LED. In this paper

a type of PSS and the corresponding manufacturing method are introduced

the cost could stay low with the wet etching

and good uniformity could also be achieved; by using our independent-designed etching system and the sulfuric acid - orthophosphoric acid mixture

a patterned structure with high duty ratio is obtained under the temperature of 280℃ after the etching duration of 40 minutes

and the etching depth is more than 2 μm; The main factors effecting on the etching rate such as duration

temperature and etching depth are also analyzed in this paper.