Graphene‐β‐Ga2O3 Heterojunction for Highly Sensitive Deep UV Photodetector Application

Kong, Weiyu; Wu, Guo‐An; Wang, Kui-Yuan; Zhang, Tengfei; Zou, Yi-Feng; Wang, Dandan; Luo, Lin‐Bao

doi:10.1002/adma.201604049

Cited by 575 publications

(363 citation statements)

References 32 publications

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“…Clearly, the performance of PD-1050 is comparable to the best values reported in the literature. In particular, extremely high responsivity and detectivity were observed, which are even higher than those of the highly sensitive solar-blind PD based on a graphene/β-Ga 2 O 3 -wafer heterojunction (39.3 A/W and 5.92 × 10 13 at 20 V) [30]. PDs, from which both the rise time (T r , defined as the time during which the current increases from 10% to 90% of the peak value) and the decay time (T d , defined as the time during which the current decays from 90% to 10% of the peak value) are extracted for each PD [1,2].…”

Section: Resultsmentioning

confidence: 89%

High-sensitivity β-Ga_2O_3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate

Qian

Zhang

Lai

et al. 2017

Opt. Mater. Express

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thin film, which yielded a smoother surface and even a terraceand-step-like morphology on the substrate, resulting in improved crystallinity of the epitaxial film. Accordingly, both the dark and photo currents of β-Ga 2 O 3 metal-semiconductor-metal (MSM) PDs were increased by the enhanced carrier mobility (μ) of the more crystalline film. However, the substrate-annealing temperature must be sufficiently high to offset the rise of the dark current and thus achieve a remarkable improvement in the photodetection properties. As a result, the PD fabricated on the 1050 °C-annealed substrate exhibited extremely high sensitivity, for example, high responsivity (R) of 54.9 A/W and large specific detectivity (D*) of 3.71 × 10 14 Jones. Both parameters were increased by one order of magnitude because of the combined effects of the dramatic increase in μ and the effective reduction in defect-related recombination centers. Nevertheless, the latter also prolonged the recovery time of the PD. These findings suggest another way to develop β-Ga 2 O 3 PD with extremely high sensitivity.

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Section: Resultsmentioning

confidence: 89%

High-sensitivity β-Ga_2O_3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate

Qian

Zhang

Lai

et al. 2017

Opt. Mater. Express

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“…β‐Ga 2 O 3 with an ultrawide bandage of 4.9 eV is considered as a promising candidate for UV detection . It has great thermal and chemical stability, determining its possibility of working at high temperatures and strong radiations.…”

Section: Introductionmentioning

confidence: 99%

Broadband Ultraviolet Photodetector Based on Vertical Ga₂O₃/GaN Nanowire Array with High Responsivity

Zhang

Ding

et al. 2019

Advanced Optical Materials

103

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attracted significant attention, which has a vast and growing number of military and civilian applications such as fire detection, missile interception, ozone hole monitoring, bioaerosol detection, astronomical imaging, and so on. [1][2][3] As the continuous improvement of devices integration, environment complexity, and interference technology, BUV photodetectors can effectively reduce false alarm rates in early warning, searching, and tracking systems, to improve the accuracy and versatility of detection systems in various situations. Many heterojunction structures based on wide-band-gap semiconductors have been reported to achieve the BUV photodetectors such as AlGaN/GaN, MgZnO/ZnO, and Ga 2 O 3 /GaN heterojunction. [4][5][6][7][8][9][10] However, AlGaN/GaN heterojunction has a high conduction band discontinuity which impedes the flow of photogenerated electrons and reduces the performance of photodetectors. [11] And high Mg-content MgZnO with high crystal quality is difficult to achieve by epitaxial growth due to the phase segregation in single wurtzite phase MgZnO. [12] β-Ga 2 O 3 with an ultrawide bandage of 4.9 eV is considered as a promising candidate for UV detection. [13,14] It has great thermal and chemical stability, determining its possibility of working at high temperatures and strong radiations. Moreover, there is a small lattice mismatch and a low conduction band offset at the interface between Ga 2 O 3 and GaN. These characteristics mean that Ga 2 O 3 /GaN heterojunction could be a potential for BUV photodetectors. Kalra et al. [6] demonstrated epitaxial β-Ga 2 O 3 /GaN-based vertical metal-heterojunctionmetal multiband UV photodetectors with the responsivity (R) of 3.7 A W −1 at 256 and 365 nm. For saving energy and broadening the application prospects of UV photodetectors, Guo et al. [15] fabricated a super-high-performance self-powered UV photodetector based on the GaN/Sn:Ga 2 O 3 p-n junction generated by depositing a Sn-doped n-type Ga 2 O 3 thin film onto a p-type GaN thick film. The responsivity at 254 nm reached up to 3.05 A W −1 without consuming external power. Lin et al. [16] used graphene as the transparent conductive layer to form graphene/β-Ga 2 O 3 /GaN heterojunction. With the help of largearea transparent electrode, a typical "sandwich" structure UV photodetector with low dark current density (1.25 × 10 −8 A cm −2 ) and high sensitivity (12.8 A W −1 ) was successfully assembled. Broadband ultraviolet (BUV) photodetectors responding to the multiband spectrum can effectively reduce false alarm rates and improve the accuracy and versatility of detection systems in various situations. A high-responsivityBUV photodetector based on vertical Ga 2 O 3 /GaN nanowire array is proposed and demonstrated. Ga 2 O 3 /GaN nanowires are obtained by partially thermally oxidizing GaN nanowires grown by molecular beam epitaxy and used to combine with a monolayer graphene film to form graphene/Ga 2 O 3 /GaN heterojunction. Moreover, the oxidation mechanism of GaN nanowires is further investigated by ...

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fiber-shaped devices that can be easily woven into desired wearable electronic devices via traditional weaving techniques. These energy storage units would ultimately be used to power the functional components (e.g., the display, [15,16] illuminator, [17] and sensors [18][19][20][21] ), which must also be wearable. These energy storage units would ultimately be used to power the functional components (e.g., the display, [15,16] illuminator, [17] and sensors [18][19][20][21] ), which must also be wearable.

…”

mentioning

confidence: 99%

Improving Wearable Photodetector Textiles via Precise Energy Level Alignment and Plasmonic Effect

Zhu

Wang

et al. 2017

Adv Elect Materials

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fiber-shaped devices that can be easily woven into desired wearable electronic devices via traditional weaving techniques. Therefore, various types of fiber-shaped devices including energy storage components like supercapacitors, [9][10][11] solar cells, [12,13] and lithium-ion batteries [14] have emerged in recent years. These energy storage units would ultimately be used to power the functional components (e.g., the display, [15,16] illuminator, [17] and sensors [18][19][20][21] ), which must also be wearable. PD, as an important member of sensors, has been widely applied for health, safety, communication, etc. [22][23][24][25] and some related works about fiber-shaped PDs have also been reported in recent years, [26][27][28][29] indicating the possibility of their wearable applications.However, different from those fibershaped energy storage components that could be easily woven into devices, the reported fiber-shaped PDs were mainly fabricated with the inorganic semiconductors based on bulky metal wires and have poor flexibility. To make things worse, the direct weaving of the fabricated fibershaped PDs will inevitably damage their surface structures and result in poor properties, including low responsivity and low on/off ratio. Hence, realizing the weaving of the fiber-shaped PDs into a piece of textile without diminishing their performances was essential for their wearable applications.Here, we propose to fabricate different components of the PDs directly on a prewoven Ni wire textile to avoid the surface damage of the fiber-shaped PD during the weaving process. Due to their excellent optoelectronic properties of ZnO, [30,31] and the outstanding optic, electrical, and mechanical properties of both Ag nanowires (NWs) [32,33] and graphene, [34,35] the flexi ble photodetector textile (PDT) is mainly composed of a dense ZnO nanorod array (NRA) grown on Ni textile as the active photoconductive layers, flexible Ag NWs, and soft graphene film as transparent electrodes. The Ni textile is the bottom electrode and the soft graphene film covers the ZnO NRA surface as the top electrode. In addition, Ag NWs were sandwiched between ZnO NRAs and graphene film, which are very important for excellent device performance. First, Ag NWs form an ohmic contact with ZnO and modifies the Ni-ZnO-graphene double Schottky heterojunction structure to a unidirectional Ni-ZnO Schottky heterojunction allowing a more efficient separation and transportation of the photo-generated carriers. [36,37] Secondly, local surface plasmon resonance (LSPR) of Ag NW Light-weight and ultraflexible-fiber-based devices that can be woven into wearable electronic products have attracted extensive attention in recent years. However, fiber-shaped photodetectors (PDs) made from bulky metalwire-based inorganic semiconductors are prone to damage with excessive bending. Therefore, this work introduces a directly constructed photodetector textile (PDT) and realizes a large-area, organized and dense weaving of fibershaped PDs for the first time. To form the struct...

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Graphene‐β‐Ga₂O₃ Heterojunction for Highly Sensitive Deep UV Photodetector Application

Cited by 575 publications

References 32 publications

High-sensitivity β-Ga_2O_3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate

High-sensitivity β-Ga_2O_3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate

Broadband Ultraviolet Photodetector Based on Vertical Ga₂O₃/GaN Nanowire Array with High Responsivity

Improving Wearable Photodetector Textiles via Precise Energy Level Alignment and Plasmonic Effect

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Graphene‐β‐Ga2O3 Heterojunction for Highly Sensitive Deep UV Photodetector Application

Cited by 575 publications

References 32 publications

High-sensitivity β-Ga_2O_3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate

High-sensitivity β-Ga_2O_3 solar-blind photodetector on high-temperature pretreated c-plane sapphire substrate

Broadband Ultraviolet Photodetector Based on Vertical Ga2O3/GaN Nanowire Array with High Responsivity

Improving Wearable Photodetector Textiles via Precise Energy Level Alignment and Plasmonic Effect

Contact Info

Product

Resources

About

Graphene‐β‐Ga₂O₃ Heterojunction for Highly Sensitive Deep UV Photodetector Application

Broadband Ultraviolet Photodetector Based on Vertical Ga₂O₃/GaN Nanowire Array with High Responsivity