Improved performance of planar GaN-based p-i-n photodetectors with Mg-implanted isolation ring

This study analyzes planar GaN p-i-n photodetectors (PDs) fabricated using Si implantation. The authors have used triple silicon implantation to form a selective n+ channel, acting like a contact wire to connect the underlying n layer and the n contact located on the surface, through a GaN-based p-i-n structure. In order to suppress the lateral current conduction from the n contact to p contact, an extra Mg-implanted isolation ring between the n+ channel and the active p-i-n layers was also performed to achieve improvement of device performance. Typical peak responsivity and cutoff wavelength of Si-implanted planar p-i-n PDs were around 0.11 AW and 365 nm, respectively.