Fast β-Ga₂O₃ Solar-Blind Photodetectors With High Detectivity on Sapphire Substrates

Abstract

Ga2O3 Solar blind photodetectors (PDs) have been widely researched in recent years due to their ultrawide bandgap. In this work, high-quality $\beta $ -Ga2O3 film with Full Width at Half Maximum (FWHM) of 0.19° was grown on sapphire substrates by MOCVD. The Ga2O3 Metal Semiconductor-Metal PDs were fabricated, showing a high response wavelength selectivity of ${1.89} \times {10} ^{{5}}$ (R $_{\text {250 nm}}$ /R $_{\text {400 nm}})$ . At 10 V, the PDs show responsivity (R) of about 500 A/W at 254 nm, specific detectivity (D*) of $1.7\times 10^{{14}}$ Jones, and response time of merely 1.5 ms, indicating its great potential for solar blind detection. Finally, images became unclear under illuminated light of about 178 nW/cm2 at 254 nm wavelength. These results open avenues for advanced Ga2O3-based optoelectronics.