High-Performance <i>β</i>-Ga<sub>2</sub>O<sub>3</sub> Solar-Blind Photodetector With Extremely Low Working Voltage
Chen Chen, Xiaolong Zhao, Xiaohu Hou, Shunjie Yu, Rui Chen, Xuanze Zhou, Pengju Tan, Qi Liu, Wenxiang Mu, Zhitai Jia, Guangwei Xu, Xutang Tao, Shibing Long
Abstract
The Ga<sub>2</sub>O<sub>3</sub> solar-blind photodetectors (SBPDs) face the tradeoff between power consumption (<inline-formula> <tex-math notation="LaTeX">$P_{\text {C}}$ </tex-math></inline-formula>) and photoresponse performance. Here, an ultrasensitive two-terminal photodetector based on <inline-formula> <tex-math notation="LaTeX">$\boldsymbol {\beta }$ </tex-math></inline-formula>-Ga<sub>2</sub>O<sub>3</sub> microflake with extremely-low working voltage and <inline-formula> <tex-math notation="LaTeX">${P}_{\text {C}}$ </tex-math></inline-formula> was achieved. At a working voltage of 2 V and <inline-formula> <tex-math notation="LaTeX">${P}_{\text {C}}$ </tex-math></inline-formula> of 10 fW, the Ga<sub>2</sub>O<sub>3</sub> SBPD exhibits superexcellent photodetection performance, including a responsivity (<inline-formula> <tex-math notation="LaTeX">${R}$ </tex-math></inline-formula>) of <inline-formula> <tex-math notation="LaTeX">${2.3}\,\,\times \,\,{10}^{{5}}\text{A}$ </tex-math></inline-formula>/W, a detectivity (<inline-formula> <tex-math notation="LaTeX">${D}^{ \boldsymbol {\ast }}$ </tex-math></inline-formula>) of <inline-formula> <tex-math notation="LaTeX">${3.5}\,\,\times \,\,{10}^{{18}}$ </tex-math></inline-formula> Jones, a photo-to-dark-current ratio (<i>PDCR</i>) of <inline-formula> <tex-math notation="LaTeX">${3.2}\,\,\times \,\,{10}^{{8}}$ </tex-math></inline-formula>, and an ultra-low dark current (<inline-formula> <tex-math notation="LaTeX">${I}_{\text {dark}}$ </tex-math></inline-formula>) of 5 fA. Strikingly, the device keeps satisfactory performance at ultralow working voltage of 0.01 V, including a <inline-formula> <tex-math notation="LaTeX">${P}_{\text {C}}$ </tex-math></inline-formula> of 0.05 fW, a <inline-formula> <tex-math notation="LaTeX">${R}$ </tex-math></inline-formula> of <inline-formula> <tex-math notation="LaTeX">${2.4}\,\,\times \,\,{10}^{{3}}$ </tex-math></inline-formula> A/W, a <inline-formula> <tex-math notation="LaTeX">${D}^{ \boldsymbol {\ast }}$ </tex-math></inline-formula> of <inline-formula> <tex-math notation="LaTeX">${5.6}\,\,\times \,\,{10}^{{16}}$ </tex-math></inline-formula> Jones, and a <i>PDCR</i> of <inline-formula> <tex-math notation="LaTeX">${3.4}\,\,\times \,\,{10}^{{6}}$ </tex-math></inline-formula>. The superior solar-blind sensitivity makes it the most excellent Ga<sub>2</sub>O<sub>3</sub> detector towards high-performance and low-<inline-formula> <tex-math notation="LaTeX">$P_{\text {C}}$ </tex-math></inline-formula> SBPD applications.