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The present research explores the fabrication of a metal insulator semiconductor Schottky barrier diode (SBD) with rare earth metal oxide (Yb2O3) thin films as insulators that are effectively developed on a large scale using the low-cost jet nebulizer spray pyrolysis technique (JNSP). The Yb2O3 thin films are deposited at various substrate temperatures (350 °C–550 °C) to ascertain its influence on the characteristic properties of the material. The structural, morphological and opto-electrical properties are investigated using various characterization techniques. Here, X-ray diffraction (XRD) analysis revealed the single crystalline cubic crystal structure of Yb2O3 thin films. Field emission scanning electron microscope (FESEM) images show the presence of uniformly distributed cage and globular like structures spread over the entire surface of the Yb2O3 films. The elemental composition study demonstrates the presence of Yb and O. The optical direct energy band gap of Yb2O3 thin films have been analyzed through UV-Visible spectra. Current – voltage measurements were analyzed in dark and light conditions for the Al/Yb2O3/p-Si structured Schottky barrier diodes (SBDs) which are fabricated with interfacial layers at different substrate temperatures. Further, the functionality of the SBDs was tested at different temperatures ranging from 30 °C to 150 °C. The experimental results of all SBDs indicate a linear reduction in the ideality factor (n) up to 2.537 and 2.059 with a slight increase in the effective barrier height (ФB) of 0.789 eV& 0.638 in dark and light conditions, respectively. The SBD fabricated at 550 °C recorded good performance, which will be suitable for thermal dependent electronic device applications. [ABSTRACT FROM AUTHOR]

In this review, we explore the last fifty years of Metal-Insulator-Semiconductor (MIS) Schottky barrier diode research, highlighting a surge in interest in tailored filaments for thin films, photovoltaic cells, and advanced electronics. The fundamental principles of MIS functionalization on the intermediate insulator layer within the MIS structure are detailed, followed by a comprehensive discussion of approaches to MIS-based diode fabrication, meticulously addressing specific details of metal, insulator and semiconductor layers. This review delves into bespoke device manufacturing methods, underscoring their significance in the scientific landscape. It examines principal materials used in production, focusing on optical, electrical applications explores the evolution of insulating materials, doping effects, manufacturing technologies and potential device applications. Challenges in MIS diode manufacturing are outlined, exploring various techniques, their advantages and disadvantages. JNSP thin film coating emerges as a preferred technique due to its cost-effectiveness, ease of handling, and non-toxic nature. From our comprehensive review, it is evident that transition metals are preferred materials in previous research. The article concludes by addressing future perspectives, guiding novel advancements and contemplating applications of bespoke filaments in optoelectronic devices and applications. This holistic exploration aims to contribute to the ongoing discourse and evolution of MIS-based devices across diverse fields. [Display omitted] • 50 years research of MIS Schottky barrier diodes: Focused on, photovoltaic applications and advanced electronics. • Key challenges associated to fabricate the MIS SBDs methods are addressed. • Recent developments of optoelectronic devices and optimal materials for the fabricate MIS structures were reviewed. [ABSTRACT FROM AUTHOR]

In this work, we have successfully prepared the nano-coral to be intact with the mesoporous of Sn-HfO2 thin films through the (jet nebulizer spray pyrolysis) JNSP technique from different Sn (5, 10, 15 Wt.%) to improve the MIS Schottky diode Al/Sn-HfO2/n-Si. To achieve the phase transformations (monoclinic to orthorhombic) in pure hafnium oxide thin films, we have added the Sn ions as the composite at optimized temperature 600 °C. The XRD characteristic used to determine the structural parameters such as the phase, grain size for pure HfO2, and composite Sn-HfO2 films. The mesoporous with irregularly shaped balls and nano coral-like morphology have been observed through FESEM images. The absorption coefficients and bandgap energy have been determined from the UV Vis spectrum. The EDAX elementary analysis has confirmed the presence of Sn, Hf, O elements in each film. The XPS spectrum has confirmed Sn's presence and binding peak with a spin-orbit on the films' surface. I-V curves of forward and reverse bias determine the barrier height, ideality factor, and saturation currents from the thermionic emission theory. All the Al/Sn@HfO2/n-Si diode parameters are strongly improved after the incorporation of Sn ions. [ABSTRACT FROM AUTHOR]

In the proposed work, the thin films have been effectively synthesized by doping the post-transition metal with rare earth metal (In-Yb2O3) on a large scale using a low-cost jet nebulizer spray pyrolysis technique at different indium (In) doping concentration (0, 1.5, 2.5, 3.5, and 4.5 wt %) with optimized substrate temperature 550 °C. The structural, morphological and opto-electrical properties are investigated using various characterization techniques. Here, the high-quality single-phase cubic structure film was observed by X-ray diffraction (XRD) analysis. The field emission scanning electron microscope (FESEM) image reveals the change in morphology with indium (In) concentration in Yb2O3 thin films. The elemental composition study approves the presence of Yb, In and O. The transmittance, optical indirect energy gap of In-Yb2O3 films have been analyzed by UV–Vis spectra. DC electrical analysis records an improved conductivity and reduced average activation energy for higher doping content of In-Yb2O3 thin films. Notably, all the diodes shows positive photo conducting properties. Specifically, when the Al/In-Yb2O3/p-Si Schottky barrier diode fabricated with higher doping concentration such as 4.5 wt. % produces the minimum ideality factor (1.791), maximum barrier height (0.692 eV) and higher photosensitive diodes. [ABSTRACT FROM AUTHOR]

Inter-connected network grains of tungsten trioxide (WO3) thin films were deposited on glass using a jet nebulizer spray pyrolysis (JNSP) technique by varying the substrate temperature at 350, 400, 450 and 500 °C. Phase transformation (monoclinic to orthorhombic) was observed during the film growth through X-ray diffraction (XRD) analysis. Field emission scanning electron microscope (FE-SEM) images revealed a better grain growth with smooth surface for 400 °C. The WO3 film deposited at 400 °C exhibits minimum band gap and maximum optical conductivity of 3.2 eV and 5.8 × 1014 (Ω.cm)−1. From the current-voltage (I–V) characteristics, the mean electrical conductivity is found to increase gradually and the activation energy reduced at higher substrate temperature. Cu/WO3/p–Si structured Schottky barrier diodes (SBDs) have been fabricated with different substrate temperature and it was tested under variable device temperatures ranging from 30 to 170 °C. The experimental results of all SBDs indicated a linear reduction in the ideality factor (n) with a small increment in effective barrier height (ΦB) with increase in device temperature, which is due to lateral inhomogeneity's at the interface. Moreover, the minimum n value of 2.89 and their corresponding ΦB of 0.71 eV were recorded for device temperature at 170 °C. Compared with other SBDs, the device fabricated at 400 °C demonstrated a better thermal stability and device performance. [ABSTRACT FROM AUTHOR]

In this paper, we report the influence of thermal annealing on structural, electrical properties V2O5 thin films and their application of SBD's. V2O5 thin films were prepared using glass substrate by sol gel spin coating technique. Films were annealed at different temperatures such as 300 °C, 400 °C and 500 °C. The prepared films were introduced as an interfacial layer between metal and semiconductor interface. V2O5 films exhibit single phase tetragonal structure and surface morphology interestingly, it was changed into nanorod-like structure at higher annealing temperature which was observed through field emission scanning electron microscopy. Atomic force microscopy reveals the surface roughness and the mentioned roughness is increasing due to the increase of annealing temperature. The elemental composition was confirmed by energy dispersive X-ray spectrum. From UV–Vis absorption spectroscopy results revealed that the band gap shows a decreasing trend on increasing the annealing temperature. Besides, we analyzed the influence of high quality vanadium pentoxide (V2O5) thin films prepared at different annealed temperatures and act as an interfacial layer between metal and semiconductor in the fabrication of Schottky diode. V2O5 films depicts high electrical conductivity (σdc) of 0.945 (S cm−1) with activation energy of 0.0747 eV (Ea) as a function of temperature. The MIS structured Cu/V2O5/n-Si based SBD's diode performance was analyzed for different temperatures ranging from 30 to 150 °C. V2O5 thin-film act as an interfacial layer on Cu/V2O5/n-Si Schottky diode was successfully explained by the thermionic emission theory. [ABSTRACT FROM AUTHOR]

Metal–insulator–semiconductor (MIS) structure of Cu/Zr–WOx/p-Si Schottky diodes with different concentrations (0, 4 and 8 wt%) of Zr content were fabricated. The interfacial layer of zirconium–tungsten oxide (Zr–WOx) film was grown on p-type silicon (p-Si) wafer using jet nebulizer spray pyrolysis (JNSP) technique at the substrate temperature of 400 °C. After that, the Cu electrode was coated on the Zr–WOx film via vacuum deposition method. The multiphase (orthorhombic and cubic) crystal structures of Zr–WOx were revealed by X-ray diffraction (XRD) pattern. The surface morphological analysis using scanning electron microscope (SEM) showed the dissimilar structures of surface and energy dispersive X-ray diffraction (EDX) confirmed the presence of W, Zr and O atoms. Using UV–Visible (UV–Vis) and DC elecrical (I–V) analysis, the minimum band gap energy and average conductivity were obtained for higher concentration (8 wt%) of Zr content. The minimum barrier height (ΦB) and minimum ideality factor (n) values were attained for 4 wt% of Cu/Zr–WOx/p-Si Schottky barrier diode (SBD) under illumination condition. [ABSTRACT FROM AUTHOR]

[Display omitted] • For the first time, facile spin coating technique is employed to fabricate Ga doped novel WO 3 films and n-Ga@WO 3 /p-Si heterojunction diode by keeping their optoelectronic applications point of view. • X-ray diffraction study reveals the orthorhombic structure of WO 3 at all Ga contents and also Ga presence was approved. • EDX study confirm the presence of Ga in WO 3 films. • SEM study shows that the morphology of WO 3 is remarkably transformed from nanoplates to fine nano-leaves with some agglomeration when Ga is doped. • Enhancement in electrical conductivity was observed with temperature as well as with Ga doping content. • Robust electrical properties of the devices were studied. • Outcomes indicates that the developed thin films and heterojunction device is quite impressive for optoelectronic applications. Hence author hope that it will a great addition to the literature for scientists and optoelectronic industries. In this work, we have fabricated the gallium doped tungsten trioxide (Ga@WO 3) films and n-Ga@WO 3 /p-Si diodes by taking various concentrations (0, 3, 6, 9, and 12 wt%) of Ga through the spin-coating method. To analyze the impact of Ga-dopant on the physical properties of WO 3 films, XRD, SEM, and robust dc electrical analyses have been used. From the XRD analysis, compared to the lower concentration of Ga dopant, the higher dopant concentrations show the presence of Ga on the o-GaWO 3 crystal structure. The nanoplates-like surface morphology was detected by SEM analysis. The temperature-dependent dc conductivity was studied by I-V characterization, and 12 wt% of Ga doped WO 3 thin film exhibits a higher conductivity value and low activation energy (E a) at room temperature. The J-V nature signifies that n-WO 3 /p-Si diode performance was enhanced using Ga dopant concentration. The diode constraints ideality factor (n) and barrier height (Φ B) values were determined from J-V, Cheung's, and Norde's functions. From J-V-T & Richardson plot (ln (J 0 /T2)), we obtain that the Φ B values were decreased with decreasing temperature. This is explained through the mechanism of thermionic emission with Φ B Gaussian distribution. The determined parameters of the fabricated films and junction diode signify that these can be employed in the applications of photodetectors and solar cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nanostructured Zn@HfO 2 thin films were through the JNSP technique. • The mesoporous with irregular balls intact nanorods-like structured morphology was observed by FESEM images. • The band gap values are receded continuously after doping. • We have fabricated Al/Zn@HfO 2 /n-Si diode for various Zn concentration. • A minimum ideality factor was obtained for 15 wt% of MIS diode. In this work, we have prepared the nanorods are intact with mesoporous of Zn@HfO 2 thin films through the JNSP technique with different concentrations of Zn (5,10,15 Wt%) to improve the MIS Schottky diode Al/Zn-HfO 2 /n-Si performance. The XRD was used to determine the structural parameters such as the phase and grain size for both pure HfO 2 and Zn@HfO 2 composite films. The mesoporous with irregular balls and nano rod-like morphology have been observed through FESEM images. The absorption coefficients and bandgap energy were calculated from the UV–vis spectrum. The EDAX analysis has confirmed that the Zn, Hf and O percentages in both films. The XPS spectrum has confirmed Zn's presence and binding natural with a spin-orbit splitting on the films' surface. By the thermionic emission theory, I-V curves of forward and reverse bias are used to determine the barrier height, ideality factor and saturation currents. All the Al/Zn@HfO 2 /n-Si diode parameters are strongly improved after the incorporation of Zn ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-Yb 2 O 3 thin films have been effectively coated with different Cu doping concentrations. • A polycrystalline with a cubic phase was obtained via JNSP route. • The UV–visible analysis indicates minimum E g and maximum σ opt of 3.14 eV and 8.67 × 1013 Ω·cm−1 • The electrical characteristics of the fabricated MIS SBDs with various Cu doped Yb 2 O 3 interface layers were investigated. • The maximum Φ B and minimum n values were obtained for 4,5 wt% of MIS diode. In the present work, transition metal doped rare earth metal oxide (Cu-Yb 2 O 3) thin films have been effectively synthesized on a large scale using low-cost jet nebulizer spray pyrolysis (JNSP) route at different copper (Cu) doping concentrations (0, 1.5, 2.5, 3.5, and 4.5 wt%) with optimized substrate temperature of 550 °C. The structural, morphological and opto-electrical properties were investigated using various characterization techniques. The X-ray diffraction (XRD) profile indicates the polycrystalline nature of all the deposited films with a cubic phase and the size of crystallites is found to increase from 11 to 31 nm. The field emission scanning electron microscope (FESEM) images reveal that the Cu doping has significant impact on the surface morphology of Cu-Yb 2 O 3 films. The atomic force microscope (AFM) analysis exposed higher roughness value for 4.5 wt% of Cu-Yb 2 O 3 films. The elemental composition study approves the presence of Yb, Cu and O in the film. The transmittance and indirect optical energy gap of Cu-Yb 2 O 3 films have been analyzed by UV–Visible spectroscopy which established the systematic band gap reduction of Yb 2 O 3 thin films from 3.68 to 3.14 eV with increasing Cu concentrations. The DC electrical studies showed a maximum conductivity and minimum average activation energy for 4.5 wt% of Cu-Yb 2 O 3 film. The electrical characteristics of the fabricated Al/Cu-Yb 2 O 3 /p-Si Schottky diode was investigated using current–voltage (I-V) measurements performed under dark and light conditions. The Φ B (0.911 eV in dark & 0.754 eV in illumination) and minimum n values (2.120 in dark and 1.757 in illuminations) were obtained for MIS diode having Cu doping concentration of 4.5 wt% in Yb 2 O 3. [ABSTRACT FROM AUTHOR]

The presence of high dielectric material between the metal and semiconductor interface played a significant role in many electronic device applications. In this work, we have fabricated Al/n-Si Schottky barrier diode by introducing nanostructured HfO 2 films as a middle layer with different substrate temperatures via JNSP technique. XRD analysis revealed significant phase change from amorphous to monoclinic phase while increasing substrate temperature. Through FESEM images, a porous structure and irregular sphere-like grains were observed. The optical energy band gap of the HfO 2 films has found to vary from 3.41 to 3.73 eV respectively. From I–V characterization, the obtained diode ideality factor was found to be decreasing and their corresponding barrier height increased with respect to substrate temperature. Particularly, the diode fabricated at 600 °C exhibited better ideality factor value (n = 3.4). We observed that the presence of highly dielectric films strongly improved the diode parameters, especially at high substrate temperature. • A nanostructured HfO2 thin films were prepared at various substrate temperature (400-600 °C) a low-cost spray pyrolysis. • A significant phase change was observed from amorphous to monoclinic while increasing the substrate temperature. • Micro-porous and ball-like grains have been recorded through FE-SEM micrographs. • The HfO2 film prepared at 600 °C shows maximum absorbance and minimum bad gap of 3.41 eV. • Al/HfO2/n-Si structured Schottky barrier diodes were fabricated with different substrate temperature. [ABSTRACT FROM AUTHOR]

We report an inorganic aqueous solution route for pure molybdenum trioxide (MoO 3) and zirconium oxide composite (MoO 3 -ZrO 2) insulating layer of Cu/MoO 3 -ZrO 2 /p-Si metal-insulator-semiconductor structured Schottky barrier diodes. These composite films were coated by Jet Nebulizer Spray Pyrolysis techniques with a substrate temperature of 500 °C and analyzed using X-ray diffraction, Field emission scanning electron microscope, DC electrical conductivity and I–V characterization. These MoO 3 -ZrO 2 films exhibited different crystal structures. Field emission scanning electron microscopes images displayed plate-like structure with improved grain size. The presence of Zr, Mo and O atoms were confirmed by energy dispersive x-ray spectrum. Optical studies shows the maximum absorption and higher optical badgap for (15 wt%) of Zr in MoO 3. DC electrical studies recorded the maximum activation energy with minimum conductivity for Zr based composite films. Current - Voltage measurements were analyzed in both dark and illuminated conditions for Cu/MoO 3 -ZrO 2 /p-Si Schottky Barrier diodes. Minimum ideality factor (2.98) and maximum barrier height (0.664 eV) was obtained for 15 wt% of Zr composite thin films. [ABSTRACT FROM AUTHOR]

Metal-insulator-semiconductor (MIS) structured Schottky barrier diodes (SBDs) are the most significant device in optoelectronic device application. Here, we demonstrated a highly rectifying SBDs using a thin interfacial layer among p-type silicon (p-Si) and metal (Cu) junction. These composite films are coated with different concentrations of Ba (0, 5, 10 and 15 wt%) using jet nebulizer spray pyrolysis (JNSP) technique with an optimized substrate temperature of 500 °C. A significant reduction of reverse saturation (Io) current was obtained on introducing the Ba–MoO 3 composite films in between Cu/p-Si interface. X-ray diffraction (XRD) pattern revealed the monoclinic crystalline phases of Ba–MoO 3 thin films along with improved grain size. Field emission scanning electron microscope (FE-SEM) images of the prepared thin films displayed a plate-like structure, which on increasing the Ba concentration transforms into a flag-like structure. The presence of constituent elements like O, Mo, Ba were confirmed by energy dispersive analysis X-Ray (EDAX) spectrum. The atomic force microscopy (AFM), exposed a smoother surface and an improved surface roughness of the film while varying the Ba concentration. Band gap energy of the Ba–MoO 3 films are found to increase after adding the Ba content. The electrical conductivity decreased with increasing Ba concentration of Ba–MoO 3 films corresponding activation energy is increased. All the fabricated Cu/Ba–MoO 3 /p-Si diodes show positive photoconducting nature, in which the ideality factor of the diode decreases gradually with Ba concentration. Hence 15 wt% of Ba shows better device performance relatively with other diodes. Image 1 • Highly rectifying Cu/Ba–MoO 3 /p-Si structured Schottky barrier diodes has been fabricated through low cost jet nebulizer spray pyrolysis technique. • The phase changes was observed (orthorombic to monoclinic) while increasing Ba concentration. • Remarkably, the plate-like and flower-like sufface morphology was revealed by FE-SEM. • Cu/Ba–MoO 3 /p-Si diode fabricated with 15 exposes a lower n = 1.92 values under light condition. • The Cu/Ba–MoO 3 /p-Si diodes highly appropriate for UV photodetector application. [ABSTRACT FROM AUTHOR]

In this study, rare earth ytterbium (Yb)-doped V 2 O 5 thin films were effectively coated on glass and Si substrates by the sol-gel method combined with the spin coating method. The films' structural, morphological, optical, and electrical properties were investigated through XRD, FESEM, UV-Vis, and I-V electrical conductivity. Doping on V 2 O 5 with low Yb content of 2, 4, and 6 ​wt % have highly affected the lattice, which is shown in tetragonal and orthorhombic structures. Morphological studies show nanorods like structured. The coated thin films yield bandgap of 3.23–3.31 ​eV. The electrical properties of Cu/Yb@V 2 O 5 /n-Si type Schottky barrier diode were studied, and calculated photodiode parameters like photosensitivity, photo-responsivity, external quantum efficiency, and detectivity. Predominantly, high photosensitivity of 5545.70% is obtained for the diode with 2 ​wt % Yb@V 2 O 5. [Display omitted] • Cu/Yb@V 2 O 5 /n-Si structured diodes are successfully fabricated. • Development of Yb@V 2 O 5 led to an increase of barrier height. • Optimum barrier height of 0.93 ​eV is obtained owing to Yb. • Yb@V 2 O 5 interface layer drawn high quantum efficiency of 37.90%. • Remarkably, 2 ​wt% Yb@V 2 O 5 is obtained high photosensitivity of 5545.70 %. [ABSTRACT FROM AUTHOR]

Herein, the fabrication of novel pure and Zr-doped SnO 2 (Zr@SnO 2) films via sol-gel spin coating process for Schottky barrier diode (SBD) application has been reported. Phase and size analysis were carried out through X-ray diffraction and Scherrer rule was used to determine crystallite size, which is noticed between 2 and 6 nm. The SEM study reveals that the fabricated films contain very fine sphere-like grains. The optical transmittance of Zr@SnO 2 thin films reveals that the grown films possess high transmittance which is good for optoelectronics. The values of energy gap for all Zr@SnO 2 films were estimated between 3.90 and 3.96 eV. The dc conductivity analysis showed that SnO 2 films possess higher electrical conductivity at 8 wt% of Zr. The barrier heights (Φ B) and ideality factor (n) of the fabricated SBDs were calculated from both J-V and Cheung's method. Better performance was noticed for Zr (8 wt%):SnO 2 /p-Si SBD. [ABSTRACT FROM AUTHOR]

• Highly sensitive MIS type Schottky diode where fabricated with various concentration of Ce. • Incorporation of Ce ions effectively reduce the surface roughness value of the V 2 O 5 films. • The fabricated Cu/Ce-V 2 O 5 /n-Si Schottky diodes are showed superior performed in under light condition. • Diode fabricated with 6 wt.% achived achived a very highy photosensitivity of 96090.78 %. In the present work, we have fabricated a highly photo responsive Schottky barrier diode based on cerium infused vanadium pentoxide thin film (Ce-V 2 O 5) as a interfacial layer. It was coated on a glass slide by low-cost sol-gel spin-coating technique and annealed at 500 °C. Structure, surface morphology, optical and electrical characteristic of Ce infused V 2 O 5 films with different Ce concentrations viz 0, 2, 4 and 6 wt% were investigated. X-ray diffraction (XRD) pattern exposed that all coated films are tetragonal structure. And a peak shift was recorded after doping Ce ion into the V 2 O 5 system. FE-SEM images showed a smooth nanorods and nanoplate-like structures in nano-scale region. Topology view by AFM showed a significant decrease in surface roughness of the film at different wt.% of Ce. The incorporation of Ce concentration based on the optical absorbance and band gap energy were studied, using UV–vis spectroscopy. Current-voltage (I–V), characteristics, photo-diode parameters of the Cu/Ce-V 2 O 5 /n-Si diodes were evaluated under dark and light exposed conditions. A maximum quantum efficiency of 25.54 % was achieved for the MIS diode fabricated with 6 % of Ce. The photosensitivity of the Cu/Ce-V 2 O 5 /n-Si diode 100 times higher than pure diode. Photodiode parameters and I–V analysis revealed that Ce with 6 wt.% is appropriate for the development of high quality photodiode and photo detector applications based to its electrical-performance. [ABSTRACT FROM AUTHOR]

Schematic representation of the Cu/Nd-V 2 O 5 -nanorods/n-Si MIS structure SBD's. • Nd-V 2 O 5 films were utilized as an interfacial layer in MIS Schottky barrier diode. • Incorporation of Nd ions in V 2 O 5 matrix causes microstructural changes. • MIS diode fabricate with 6 wt% unveiled higher photo-sensitivity of 19,427.80%. In the present work, Nd (x) -V 2 O 5 -nanorods (x = 2, 4 and 6 wt%) thin films were prepared via a spin coating technique. X-ray diffraction analysis shows tetragonal phases for neodymium substituted films. The concern diffraction angle shifted to higher angle owing to substitution in vanadium that implies complete occupation in V 2 O 5 crystal lattice. FE-SEM images are flaunting one dimensional nano-rod formation. Conductivity analysis of fabricated diode at different temperature reveals their activation energies (E a) and these energies are high when rare earth interfaced diode in contrast to pure vanadium films. The essential current (I) and voltage (V) characteristics of junction diodes express nonlinear behaviour. The photodiode parameters like n, Ф B , I 0 , P s , R, QE and D* are calculated by dark and light condition. The photodiode performance under lighting condition is superior than dark. [ABSTRACT FROM AUTHOR]