High Photo Sensing Performance With Electro-Optically Efficient Silicon Based ZnO/ZnMgO Heterojunction Structure (original) (raw)
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IEEE Transactions on Nanotechnology, 2017
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Interface architecture determined the performance of ZnO nanorods-based photodetectors
Chemical Physics Letters, 2014
High density ZnO nanorods grown on silicon oxide-coated Si (1 1 1) substrates were used to fabricate an MSM UV photodetector. The maximum sensitivity of the detector was about 1150, which was maintained over the wide range of applied bias. The photodetector responsivity increased slightly until reaching a maximum value at 374 nm and exhibited a sharp cutoff at 378 nm. The obtained photodetector responsivity was as high as 1.1 A/W. The detector shows fast photoresponse with a rise time of 0.008 s and a decay time of 0.021 s.
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Journal of Materials Science: Materials in Electronics, 2015
The fabrication of planar Al/ZnO/Si heterojunction photodetectors has received considerable attention. The crystalline quality of ZnO plays an important role in the properties of the fabricated device. In this study, ZnO micro-rods were grown on Si (100) without any catalysts using atmospheric pressure chemical vapor deposition, and were characterized to determine their potential for application in highly photosensitive ZnO/Si photodetectors. The ZnO rods were grown with various diameters and had a wurtzite structure oriented in the (002) plane. The effect of the substrate temperature on the crystalline structure was studied in the range of 450-750°C. The planar structure of the Al/ZnO heterojunction photodetector indicated that the device is highly sensitive to ultraviolet and visible light. The photoresponse of the fabricated Al/ZnO device had a peak at 360 nm. The responsivity of the device reached 0.03 at a bias voltage of 1 V and reached 0.085 at a bias voltage of 5 V. The responsivity increased to 0.121 as the bias voltage increased to 10 V. The quantum efficiency of the device was 11, 32, and 42 % at bias voltages of 1, 5, and 10 V, respectively.
Fabrication And Characterization Of Al / Zno / Si / Al Photodetector
2017
In this research, ZnO nanostructure have been prepared from colloidal ZnO nanoparticles NPs utilizing chemical method. The structural, morphological and optical of ZnO thin film has been studied. XRD anaylsis assure that the ZnO thin film were of wurtzite hexagonal crystal structure. AFM investigations showed that the produced ZnO particles have ball-shape with good disposability. The optical energy band gap of ZnO thin film has been determined from optical properties and found to be in the range (3.2 eV). Al/ZnO/Si/Al photodetector heterojunction have two peaks of response located at 415 nm and 780 nm with max sensitivity of 0.6 A/W. Keywords—ZnO nanoparticle , optical properties, structural properties, 1Introduction :Significant research efforts have been made in recent years for developing highly oriented and transparent ZnO thin films, because of their potential application in transparent electrode in display, window layers of solar cells, field emitters, ultraviolet laser emiss...
Fabrication and Characterization of ZnO Photodetectors with High Gain
Journal of Nanoelectronics and Optoelectronics, 2010
We report fabrication and characterization of MSM UV photodetector based on Pd/ZnO thin film. The ZnO thin film was grown on glass substrate by thermal oxidation of pre-deposited zinc films by vacuum deposition technique. With applied voltage in the range from −3 V to 3 V we estimated the contrast ratio, responsivity, detectivity for an incident radiation of 0.1 mW at 365 nm wavelength. Our device exhibited a high gain which is attributed to the hole trapping at semiconductor-metal interface. I-V characteristics were studied by using microprobe arrangement. The parameter such as ideality factor, leakage current, resistance-area-product and barrier height were extracted from the measured data. The surface morphological and the structural properties of the thin film were studied by atomic force microscope.
Low dark current and high speed ZnO metal–semiconductor–metal photodetector on SiO2/Si substrate
Applied Physics Letters, 2014
ZnO thin films are deposited by radio-frequency magnetron sputtering on thermally grown SiO2 on Si substrates. Pt/Au contacts are fabricated by standard photolithography and lift-off in order to form a metal-semiconductor-metal (MSM) photodetector. The dark current of the photodetector is measured as 1 pA at 100 V bias, corresponding to 100 pA/cm2 current density. Spectral photoresponse measurement showed the usual spectral behavior and 0.35 A/W responsivity at a 100 V bias. The rise and fall times for the photocurrent are measured as 22 ps and 8 ns, respectively, which are the lowest values to date. Scanning electron microscope image shows high aspect ratio and dense grains indicating high surface area. Low dark current density and high speed response are attributed to high number of recombination centers due to film morphology, deducing from photoluminescence measurements. These results show that as deposited ZnO thin film MSM photodetectors can be used for the applications needed...
Journal of Alloys and Compounds, 2022
Αn isotype heterojunction n +-ZnO/n-Si photodetector is developed, demonstrating wavelength-selective or broadband operation, depending on the applied bias voltage. Additionally, at self-powered (zero bias) operation, it distinguishes between UV, visible, and near IR (NIR) photons by polarity control of the photocurrent. The photodetector is developed by atomic layer deposition (ALD) of ZnO on n-Si, followed by electric contact deposition and annealing. Photoluminescence measurements reveal high optical quality and improved crystallinity of annealed ZnO on silicon. Photocurrent measurements as a function of illumination wavelength and bias voltage show small negative values in the UV-visible spectral range at zero and positive bias voltage and high positive values in the NIR spectral range. For these measurements, we consider the electric contact to ZnO as the anode and the electric contact to silicon as the cathode. At negative bias voltage, the device shows broadband operation with high photocurrent values across the UV-vis-NIR.
Solution derived p-ZnO/n-Si nanowire heterojunctions for photodetection
Chemical Physics Letters, 2016
While there is considerable interest in zinc oxide nanomaterials for optoelectronics research, one weakness of the material is the difficulty in producing p-type zinc oxide. This can be attributed to a number of factors such as acceptor instability, donor compensation during growth, and the formation of deep acceptors. Recently, it was discovered that antimony is a stable p-type dopant in hydrothermally grown ZnO nanowires, and this method has been modified to produce ultralong nanowires and homojunction thin films. In order to broaden the applicability of this new material, it is important to investigate how it interacts with other semiconducting nanomaterials.
Journal of the American Chemical Society, 2010
This Communication reports a low-cost solution fabrication of wafer-scale ZnO/Si branched nanowire heterostructures and their high photodetection sensitivity, with an ON/OFF ratio larger than 250 and a peak photoresponsivity of 12.8 mA/W at 900 nm. This reported unique 3D branched nanowire structure offers a generic approach for the integration of new functional materials for photodetection and photovoltaic applications.
Nano Energy, 2017
The broadband and self-powered photodetectors have attracted significant attention due to the versatility and without extra energy. In this work, we fabricate a self-powered and broadband photodetector based on Si/ZnO/CdO three-component heterojunctions. The photodetector has a fast response time (shorter than 0.45s) to the ultraviolet and visible illumination at 0V bias. CdO film is used as the transparent electrode because of the superior electrical characterization and the appropriate band structure of ZnO/CdO, which facilitates electrons transferring from ZnO nanorods to the CdO electrod and reflects holes back into the ZnO, thus reducing recombination at the ZnO/CdO interface and enhancing photocurrent. Moreover the performance of the photodetector is optimized and significantly enhanced by the piezo-phototronic effect of ZnO nanorods. This work may provide a potential approach to enhance the performance of self-powered and broadband photodetectors.