High performance solar-blind photodetectors based on MOCVD grown β - G a 2 O 3 with hydrogen plasma treatment

Abstract The growing demand for efficient solar-blind ultraviolet photodetectors (SBPDs) has fueled interest in the exceptional properties of β - G a 2 O 3 . Here, SBPDs with a metal–semiconductor–metal structure are fabricated based on β - G a 2 O 3 thin films. The ( 2 ¯ 01) oriented β - G a 2 O 3 is grown on c -plane sapphire using metal–organic chemical vapor deposition. Hydrogen as a shallow donor is introduced into the β - G a 2 O 3 surface layer selectively on the area underneath contacts by plasma treatment to enhance the ohmic contact. As a result, superexcellent performances are demonstrated, including a remarkable responsivity of 3.0 × 10 4 A W −1 at a wavelength of 238 nm, specific detectivity of 1.2 × 10 17 Jones and an external quantum efficiency of 1.5 × 10 7 % . Also, faster ris