-
To meet the urgent demand for high-performance photodetectors in emerging solar-blind ultraviolet communication applications, this study systematically designs and implements a fully transparent β-Ga2O3 solar-blind photodetector based on a back-illumination architecture. The device is fabricated using RF magnetron sputtering to epitaxially grow high-quality β-Ga2O3 films (~300 nm in thickness, ~4.98±0.05 eV in bandgap) on double-polished sapphire substrates, with indium tin oxide (ITO) interdigitated electrodes forming efficient quasi-Ohmic contacts with n-type Ga2O3. The core advantage of this design lies in exploiting the high deep-UV transmittance of double-polished sapphire substrates, enabling incident photons to completely bypass the UV-absorbing ITO electrodes and eliminate photon loss caused by electrode shadowing effects in traditional front-illumination configurations. Consequently, the device demonstrates exceptional optoelectronic performance: a maximum responsivity of 0.46 A/W corresponding to an external quantum efficiency of 222.4%, an outstanding UV/visible rejection ratio of 1.2×104, a minimum noise equivalent power of 1.52 pW/Hz1/2, and a peak specific detectivity of 1.39×1011 Jones, with fast response times of 24 μs (rise) and 1.24 ms (decay). Building on this high-performance detector platform, we further explore its multifunctional application potential by constructing a polarization detection system that utilizes the intrinsic lattice anisotropy of monoclinic β-Ga2O3, and successfully demonstrating a non-line-of-sight (NLOS) UV communication system that validates high-fidelity information transmission in complex scattering channels. This work provides effective physical insights and experimental basis for developing next-generation Ga2O3-based optoelectronic devices with integrated high sensitivity, polarization resolution, and NLOS communication capabilities, showing promising applications in secure communications and polarization imaging.
-
Keywords:
- gallium oxide /
- solar-blind photodetector /
- polarization detection /
- non-line-of-sight solar-blind UV communication
-
图 1 (a) 磁控溅射沉积系统示意图; (b) 在双面抛光Al2O3衬底上沉积的β-Ga2O3薄膜的XRD谱图; (c) β-Ga2O3薄膜表面的AFM形貌图; (d) 薄膜的光学吸收光谱, 插图为(αhν)2与hν的关系图, 用于带隙估算
Figure 1. (a) Schematic diagram of the magnetron sputtering deposition system; (b) XRD pattern of the β-Ga2O3 thin film deposited on a double-side polished Al2O3 substrate; (c) AFM surface morphology of the β-Ga2O3 film; (d) optical absorption spectrum of the film, with the inset showing the (αhν)2 versus hν plot for bandgap determination.
图 2 (a) 基于Ga2O3的全透明日盲紫外探测器结构示意图; (b) 在正入射与背入射光照模式下的I-V特性曲线; (c) 器件的归一化光谱响应; (d) 在暗态和255 nm紫外光照下的噪声电流比较
Figure 2. (a) Schematic structure of the fully transparent Ga2O3-based solar-blind UV photodetector; (b) I-V characteristics under front-illumination and back-illumination; (c) normalized spectral responsivity of the device; (d) noise current measured in the dark and under 255 nm UV illumination.
图 3 (a) 在黑暗和254 nm紫外光照条件下, β-Ga2O3全透明日盲探测器的I-V特性曲线; (b) 电阻特性; (c) 响应度、外量子效率与入射光功率强度的对应关系; (d) 等效噪声功率、比探测率与入射光功率强度的对应关系
Figure 3. (a) I-V characteristics of the β-Ga2O3 transparent solar-blind photodetector in the dark and under 254 nm UV illumination; (b) resistance behavior of the device as a function of applied bias; (c) variation of R and EQE with incident optical power; (d) dependence of NEP and specific D* on incident optical power.
图 4 (a) 在5 V偏压和255 nm紫外光照射下, 探测器背入射光开关响应随光强变化的动态特性; (b) 在5 V电压下, 266 nm脉冲激光激发时的瞬态光响应
Figure 4. (a) Dynamic back-illumination switching response of the device under 5 V bias and 255 nm UV illumination at varying intensities; (b) transient photoresponse of the Ga2O3 transparent solar-blind photodetector under 266 nm pulsed laser excitation at 5 V bias.
图 5 (a) 正入射模式下Ga2O3全透明日盲探测器的示意图; (b) 背入射模式下的示意图; (c), (d) 器件截面的电场分布仿真图, 其中(c)为正入射模式, (d)为背入射模式(颜色由蓝到红代表电场强度强度由弱到强)
Figure 5. (a) Schematic of the Ga2O3 transparent photodetector under front-illumination; (b) schematic under back-illumination mode; simulated electric field distribution in the device cross-section for (c) the front-illumination mode and (d) the back-illumination mode, the color scale from blue to red represents the electric field intensity from low to high.
图 6 (a) ITO/Ga2O3的能带偏移示意图; (b) 深紫外照射下ITO/Ga2O3/ITO器件的能带结构及载流子传输示意图
Figure 6. (a) Schematic illustration of ITO/Ga2O3 band alignment; (b) energy band diagram and carrier transport mechanism of the ITO/Ga2O3/ITO device under deep UV illumination.
图 7 (a) 深紫外偏振测试系统实物图; (b) 255 nm, 100 μW/cm2紫外光照射下的光电流与偏振角度的极坐标图; (c) 不同光强下, 从0°到360°偏振角的光响应曲线; (d) 偏振比随入射光强的变化关系
Figure 7. (a) Photograph of the deep-UV polarization measurement setup; (b) polar plot of photocurrent versus polarization angle under 255 nm, 100 μW/cm2 UV illumination; (c) angular-dependent photoresponse from 0° to 360° at various incident power levels; (d) polarization ratio as a function of incident light intensity.
图 8 (a) 非视距日盲通信系统的工作原理示意图; (b) 实验装置实物图; (c) 不同发射信号下接收端I-t响应曲线
Figure 8. (a) Schematic of the non-line-of-sight solar-blind UV communication system; (b) photograph of the experimental setup; (c) I-t response curves of the receiver for different transmitted signal patterns.
-
[1] Guo L, Guo Y N, Wang J X, Wei T B 2021 J. Semicond. 42 081801
Google Scholar
[2] Kalra A, Muazzam U U, Muralidharan R, Raghavan S, Nath D N 2022 J. Appl. Phys. 131 150901
Google Scholar
[3] Xu Z Y, Sadler M 2008 IEEE Commun. Mag. 46 67
[4] Tan Y F, Qiao Q , Zhao T G , Chang S L , Zhang Z F , Zang J H , Lin C N, Shang Y Y , Yang X, Zhou J W , Yu X , Yu X M , Shan C X 2024 J. Mater. Sci. Technol. 190 200
[5] Zhang Q Y, Li N, Zhang T, Dong D M, Yang Y T, Wang Y H, Dong Z G, Shen J Y, Zhou T H, Liang Y L, Tang W H, Wu Z P, Zhang Y, Hao J H 2023 Nat. Commun. 14 418
[6] Zhang H C, Liang F Z, Yang L, Gao Z X, Liang K, Liu S, Ye Y K, Yu H B, Chen W, Kang Y, Sun H D 2024 Adv. Mater. 36 2405874
Google Scholar
[7] Qin Y, Long S B, Dong H, He Q M, Jian G Z, Zhang Y, Hou X H, Tan P J, Zhang Z F, Lv H B, Liu Q, Liu M 2019 Chin. Phys. B 28 018501
Google Scholar
[8] Hu Z G, Cheng Q, Zhang T, Zhang Y X, Tian X S, Zhang Y C, Feng Q, Xing W, Ning J, Zhang C F, Zhang J C, Hao Y 2023 J. Lumin. 255 119596
Google Scholar
[9] Yang H R, Cheng T H, Xin Q, Liu Y Y, Feng H Y, Luo F, Mu W X, Jia Z T, Tao X T 2023 ACS Appl. Mater. Interfaces 15 32561
Google Scholar
[10] Nie Y J, Jiao S J, Yang S, Zhao Y, Gao S Y, Wang D B, Yang X, Li Y F, Fu Z D, Li A M, Wang J Z, Zhao L C 2025 Small 21 2501442
Google Scholar
[11] 况丹, 徐爽, 史大为, 郭建, 喻志农 2023 物理学报 72 038501
Google Scholar
Kuang D, Xu S, Shi D W, Guo J, Yu Z N 2023 Acta Phys. Sin. 72 038501
Google Scholar
[12] Zhang Q Y, Dong D M, Zhang T, Zhou T H, Yang Y T, Tang Y J, Shen J Y, Wang T J, Bian T Y, Zhang F, Luo W, Zhang Y, Wu Z P 2023 ACS Nano 17 24033
Google Scholar
[13] Lu Y, Miranda C, Tang X, Liu Z Y, Khandelwal V, Krishna S, Li X H 2025 Adv. Mater. 37 2406902
Google Scholar
[14] Dong D M, Peng M, Zhang T, Zhang S C, Ma X T, Tang Y J, Cao Y L, Zhang Q Y, Zhang F, Zhang Y, Wu Z P 2025 ACS Photon. 12 3653
Google Scholar
[15] Wang Y F, Fu S H, Han Y R, Gao C, Fu R P, Wu Z, Cui W Z, Li B S, Shen A D, Liu Y C 2025 Small 21 e2406989
Google Scholar
[16] Chen W C, Xu X Y, Li M H, Kuang S L, Zhang K H, Cheng Q J 2023 Adv. Opt. Mater. 11 2202847
Google Scholar
[17] Dang X M, Jiao T, Chen P R, Yu H, Han Y, Li Z, Li Y H, Dong X 2024 Chin. J. Lumin. 45 476
Google Scholar
[18] Yan S Q, Jiao T, Ding Z J, Zhou X Y, Ji X Q, Dong X, Zhang J W, Xin Q, Song A M 2023 Adv. Electron. Mater. 9 2300297
Google Scholar
[19] Labed M, Park B I, Kim J, Park J H, Min J Y, Hwang H J, Kim J, Rim Y S 2024 ACS Nano 18 6558
Google Scholar
[20] Cui M, Xu Y, Sun X Y, Wang Z P, Gong H H, Chen X H, Hu T C, Zhang Y J, Ren F F, Gu S L, Ye J D, Zhang R 2022 J. Phys. D: Appl. Phys. 55 394003
Google Scholar
[21] Shen G H, Liu Z, Zhang M L, Guo Y F, Tang W H 2023 IEEE Electron Device Lett. 44 1140
Google Scholar
[22] Shen G H, Liu Z, Tan C K, Jiang M M, Li S, Guo Y F, Tang W H 2023 Appl. Phys. Lett. 123 041103
Google Scholar
[23] 董典萌, 汪成, 张清怡, 张涛, 杨永涛, 夏翰驰, 王月晖, 吴真平 2023 物理学报 72 097302
Google Scholar
Dong D M, Wang C, Zhang Q Y, Zhang T, Yang Y T, Xia H C, Wang Y H, Wu Z P 2023 Acta Phys. Sin. 72 097302
Google Scholar
[24] 王露璇, 刘奕彤, 史方圆, 祁纤雯, 沈涵, 宋瑛林, 方宇 2023 物理学报 72 214202
Google Scholar
Wang L X, Liu Y T, Shi F Y, Qi X W, Shen H, Song Y L, Fang Y 2023 Acta Phys. Sin. 72 214202
Google Scholar
[25] Zhang Y Q, Wang Y F, Fu R P, Ma J G, Xu H Y, Li B S, Liu Y C 2022 J. Phys. D: Appl. Phys. 55 324002
Google Scholar
[26] Wang X, Chen Z W, Guo D Y, Zhang X, Wu Z P, Li P G, Tang W H 2018 Opt. Mater. Express 8 2918
Google Scholar
[27] 张裕, 刘瑞文, 张京阳, 焦斌斌, 王如志 2024 物理学报 73 098501
Google Scholar
Zhang Y, Liu R W, Zhang J Y, Jiao B B, Wang R Z 2024 Acta Phys. Sin. 73 098501
Google Scholar
[28] Kananen B E, Giles N C, Halliburton L E, Foundos G K, Chang K B, Stevens K T 2017 J. Appl. Phys. 122 215703
Google Scholar
[29] McCluskey M D 2020 J. Appl. Phys. 127 2002230
[30] Neal A T, Mou S, Rafique S, Zhao H P, Ahmadi E, Speck J S, Stevens K T, Blevins J D, Thomson D B, Moser N, Chabak K D, Jessen G H 2018 Appl. Phys. Lett. 113 062101
Google Scholar
[31] Liu H W, Zhou S R, Zhang H, Ye L J, Xiong Y Q, Yu P, Li W J, Yang X, Li H L, Kong C Y 2022 J. Phys. D: Appl. Phys. 55 305104
Google Scholar
[32] 许怡红, 范伟航, 王尘 2025 物理学报 74 028104
Google Scholar
Xu Y H, Fan W H, Wang C 2025 Acta Phys. Sin. 74 028104
Google Scholar
[33] Huan Y W, Sun S M, Gu C J, Liu W J, Ding S J, Yu H Y, Xia C T, Zhang D W 2018 Nanoscale Res. Lett. 13 246
Google Scholar
[34] Musztyfaga S M, Gawlinska N K, Socha R, Panek P 2023 Materials 16 1363
Google Scholar
[35] 刘增, 李磊, 支钰崧, 都灵, 方君鹏, 李山, 余建刚, 张茂林, 杨莉莉, 张少辉, 郭宇锋, 唐为华 2022 物理学报 71 028104
Liu Z, Li L, Zhi Y S, Du L, Fang J P, Li S, Yu J G, Zhang M L, Yang L L, Zhang S H, Guo Y F, Tang W H 2022 Acta Phys. Sin. 71 208501
[36] Zhang Y H, Liang H L, Xing F, Gao Q Q, Feng Y, Sun Y P, Mei Z X 2024 Sci. China Phys. , Mech. Astron. 67 247312
Google Scholar
[37] Zhang G, Wang Z Y, Chen S W, Xi Z Y, Wu C, Hu H Z, Liu Z, Wu F M, Wang S L, Fang Z L, Tang W H, Guo D Y 2025 Laser Photonics Rev. 19 e00255
Google Scholar
[38] Wu C, Zhang G, Jia J H, Hu H Z, Wu F M, Wang S L, Guo D Y 2024 J. Phys. Chem. Lett. 15 3828
Google Scholar
[39] Zhao K, Yang J H, Wang P, Zhou Z Q, Long H R, Xin K Y, Liu C, Han Z, Liu K H, Wei Z M 2024 Adv. Mater. 36 e2406559
Google Scholar
[40] Zhong W H, Huang H, Liu Y Q, Jing J W, Wu W T, Liu W Z, Zhao X L, Long S B, Xu H Y 2025 Appl. Phys. Rev. 12 011420
Google Scholar
DownLoad:
Metrics
- Abstract views: 358
- PDF Downloads: 5
- Cited By: 0
