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Nowadays, the development of GPS (Global Positioning System) technology has become mature, and has begun to develop in the direction of high-precision positioning and navigation. Navigation data such as position, speed, and heading provided by GPS are very important in military or commercial fields. However, in addition to improving the accuracy of positioning, its reliability must also be considered. Therefore, RTK (Real Time Kinematic) differential positioning technology is used to perform real-time error correction and basic inertial components consist of gyroscope, accelerometer, and magnetic compass are used to compensate and improve reliability. In this study, a car is used as a vehicle to experiment the route near the campus. The collected XYZ position coordinate data of the non-difference, differential positioning, and original vehicle are calculated by MATLAB offline operation to obtain $\lambda($longitude), $\Phi$ (latitude), h (height), and the data sensed by integrated inertial elements in the GPS signal shaded roads as auxiliary navigation, and then compare it with the existing and non-differential positioning methods to obtain a more optimized drawing path. The map achieves the compensation effect. In this study, the position of the shaded road is obtained by the second integration of the gyroscopic azimuth change and the heading angle of the magnetic compass through the accelerometer signal. The Extended Kalman Filter algorithm is used as its solution to estimate position, speed and heading of the vehicle in real time to achieve high accuracy and high reliability of real-time positioning and navigation.

Bi1-xMgxFeO3 (BMFO, x = 0, 0.02, 0.04, 0.06 and 0.08) multiferroic films were directly synthesized on flexible stainless steel (FSS), save the bottom electrode process, by means of sol&ndash, gel spin-coating technology. The effects of different bending conditions on ferroelectric, dielectric and leakage-current properties of BMFO films were investigated. The leakage-current densities of BiFeO3 (BFO, x = 0) and BMFO (x = 0.06) films were 5.86 &times, 10&minus, 4 and 3.73 &times, 7 A/cm2, which shows that the BMFO (x = 0.06) has more than three orders of magnitude lower than that of BFO film. The residual polarization (2 Pr) can be enhanced from 120 to 140 &mu, C/cm2. The proper doping of Mg in BiFeO3 film could provide an effective method for reducing the leakage-current values as well as boosting the ferroelectric properties. In this study, the leakage-current mechanism of low electric field and high electric field of BMFO film is analyzed and established. In addition, the flexible BMFO film maintains practical ferroelectric and leakage-current properties at retention time of 106 s under different symmetry bending conditions. These results indicate that the BFMO film will be very practical in opto-electronic and storage device applications.

Zn1&minus, xMgxO (x = 0, 0.03, 0.05, and 0.07) nanocrystalline films were grown on silicon substrates using the sol&ndash, gel method. Furthermore, Zn1&minus, xMgxO vertically aligned hexagonal symmetrical nanorods with six reflection symmetries were fabricated on pure ZnO-seeded layer n-type silicon substrates via a low-temperature hydrothermal method to enhance the ultraviolet (UV) light response. The crystal microstructures and surface morphologies of nanocrystalline films and nanorod arrays were determined by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Transmission spectra showed that the increasing Mg content will increase the band gap energy from 3.28 to 3.46 eV. However, the current&ndash, voltage curves in the dark and under UV illumination showed that the UV response did not improve by the incorporation of magnesium. We changed the flat surface of films into symmetrical nanorod arrays and demonstrated they can significantly enhance the normalized photo-to-dark-current ratio up to ten times.

In this study, the Mg doping effects on the nanostructural dependence of photoluminescence and the photosensing properties in Zn1−xMgxO (x = 0.01, 0.03, and 0.05) nanorod arrays were systematically examined. The vertical-aligned nanorod arrays were separately grown on ZnO-seeded n-Si substrates via a low-temperature hydrothermal process. X-ray diffraction analysis revealed that all Zn1−xMgxO nanorod arrays exhibited the same preferentially c-oriented wurtzite structure. Images of all the Zn1−xMgxO nanorod arrays provided by field emission scanning electron microscope showed that both the length and diameter of the Zn1−xMgxO nanorod arrays increased with increasing Mg doping concentration. Also, an enhanced blue-shifted ultraviolet (UV) emission and a reduced visible emission were observed from the photoluminescence spectra of the Zn1−xMgxO nanorod arrays. The former indicated the decrease of defects and the latter indicated the enhancement of the crystallinity and the increase in optical bandgap. Current–voltage curves were separately measured in the dark and under UV illumination. Finally, the mechanism of the Mg doping effects on the corresponding defects, bandgap, and UV photosensing characteristics of the Zn1−xMgxO nanorod arrays was investigated in detail.

By a sol–gel method, a BiFeO3 (BFO) capacitor is fabricated and connected with the control thin film transistor (TFT). Compared with a control thin-film transistor, the proposed BFO TFT achieves 56% drive current enhancement and 7–28% subthreshold swing (SS) reduction. Moreover, the effect of the proposed BiFeO3 capacitor on IDS-VGS hysteresis in the BFO TFT is 0.1–0.2 V. Because dVint/dVGS > 1 is obtained at a wide range of VGS, it reveals that the incomplete dipole flipping is a major mechanism to obtain improved SS and a small hysteresis effect in the BFO TFT. Experimental results indicate that sol-gel BFO TFT is a potential candidate for digital application.

Electrical conduction mechanism and bipolar resistive switching properties of the manganese oxide thin films resistive random access memory (RRAM) devices for high resistive status and low resistive status (HRS/LRS) were investigated and discussed. The electrical and physical properties of post-treatment manganese oxide thin films for different oxygen concentration parameters were measured by x-ray diffraction (XRD) and operation current versus applied voltage ( I-V ) measurement. For I-V curves in different temperature, the ohmic conduction, space charge limited conduction (SCLC), schottky emission conduction, and hopping conduction mechanism of manganese oxide RRAM devices were discussed and verified in initial metallic filament path forming process. Finally, the excess oxygen ions, vacancy, and defect factor resulting in bipolar and unipolar resistive switching behavior of thin films RRAM devices will be explained and investigated by metallic filament path forming model.

GaAs p-i-n solar cells are studied using electroreflectance (ER) spectroscopy, light beam induced current (LBIC) mapping and photovoltaic characterization. Using ER measurements, the electric field across the pn junction of a wafer can be evaluated, showing 167 kV/cm and 275 kV/cm in the built-in condition and at &minus, 3 V reverse bias, respectively. In order to understand the effect of the interval between metal grids on the device&rsquo, s solar performance, we performed LBIC mapping and solar illumination on samples of different grid spacings. We found that the integrated photocurrent intensity of LBIC mapping shows a consistent trend with the solar performance of the devices with various metal grid spacings. For the wafer used in this study, the optimal grid spacing was found to be around 300 &mu, m. Our results clearly show the importance of the metal grid pattern in achieving high-efficiency solar cells.

The bipolar switching properties and electrical conduction mechanism of vanadium oxide thin-film resistive random-access memory (RRAM) devices obtained using a rapid thermal annealing (RTA) process have been investigated in high-resistive status/low-resistive status (HRS/LRS) and are discussed herein. In addition, the resistance switching properties and quality improvement of the vanadium oxide thin-film RRAM devices were measured by x-ray diffraction (XRD) analysis, x-ray photoelectron spectrometry (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and current–voltage (I–V) measurements. The activation energy of the hopping conduction mechanism in the devices was investigated based on Arrhenius plots in HRS and LRS. The hopping conduction distance and activation energy barrier were obtained as 12 nm and 45 meV, respectively. The thermal annealing process is recognized as a candidate method for fabrication of thin-film RRAM devices, being compatible with integrated circuit technology for nonvolatile memory devices.

Pr-doped ZnO thin films (Zn1−xPrxO) (x = 0.00, 0.01, 0.02, 0.04) were prepared on fluorine-doped tin oxide substrates by means of the sol–gel method and spin coating technology, followed by rapid thermal annealing treatment at 800 °C. The influence of Pr content on the structural and optical properties of the Zn1−xPrxO thin film was examined and discussed. The wurtzite hexagonal structural characteristics were investigated by X-ray diffraction analysis, and Pr3+ substitution for Zn2+ ions was indicated. Finally, the typical bipolar current-voltage switching curves and electrical conduction model of Zn1−xPrxO film resistive random access memory devices were discussed and investigated for low resistance state/high resistance state in the initial forming process.

FeS2 pyrite films are used in a variety of applications including solar cells and, the potential scope for their utilization is increasing as their synthetic methods become more economical while maintaining or enhancing their high light absorption coefficients. The glass substrate temperature dependence on the formation of FeS2 pyrite films was investigated with respect to their optical and physicochemical properties. During the thermochemical spraying process the temperature was varied in the range of 190-290 °C. FeS2 nanocrystalline (40-70 nm) films, formed as a result of atmospheric spraying with glass substrate temperatures above 260 °C, were observed by SEM. Opto-electronic studies revealed that the nanocrystalline films had a direct band gap (1.3-1.6 eV) with a high light absorption coefficient (α > 7 × 104 cm−1 for λ

Bipolar resistive switching properties and endurance switching behavior of the neodymium oxide (Nd2O3) thin films resistive random access memory (RRAM) devices for a high resistive status/low resistive status (HRS/LRS) using a low temperature supercritical carbon dioxide fluid (SCF) improvement post-treatment process were investigated. Electrical and physical properties improvement of Nd2O3 thin films were measured by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and current versus voltage (I-V) measurement. The metal-like behavior of ohmic conduction mechanism and metallic cluster reaction of hopping conduction mechanism in initial metallic filament path forming process of the SCF-treated thin films RRAM devices was assumed and discussed. Finally, the electrical conduction mechanism of the thin films RRAM derives for set/reset was also discussed and verified in filament path physical model.

Surface plasmon resonance mediated by Gold (Au) nanoparticles (NPs) was employed to enhance the ultraviolet (UV) response of p-Si/n-ZnO nanorod (NR) heterojunction photodetectors (HPDs). In the ZnO NRs with Au NP covering, the photoluminescence spectrum shows that the band-to-band emission of ZnO (384 nm) is increased by a magnitude of 3, and the deep-level emissions (450-700 nm) are drastically decreased as compared with HPDs without coverings of Au NPs. Such a result increases UV-to-visible rejection ratio from 214 to 6180 and it attributes that the defect-level emissions of ZnO induce surface plasmon resonance in Au NPs and then enhances the emissions, exciting a large quantity of electrons crossing over the Au NP/ZnO interface barrier. Consequently, these electrons are transferred to the ZnO conduction band from the Au NPs, causing a photocurrent gain and the quantum efficiency is as high as 1157% at 2 V reverse bias.

Herein transparent Zn1-xFexO nanocrystalline films have been prepared on glass substrates by sol-gel method followed by rapid thermal annealing treatment. The effecs of Fe doping on the microstructure, transmittance and magnetism of Zn1-xFexO nanocrystalline films are investigated. The x-ray diffraction patterns of all compositions show the same wurtzite hexagonal structure with the space group P63/mc. FE-SEM images show uniform spherical grains of all Zn1-xFexO nanocrystalline films in which the grain size decreases progressively from 38.85 nm (x = 0.00) to 15.35 nm (x = 0.04). Red shift of the absorption edges is obtained from the optical transmittance spectra from 372 nm of undoped ZnO film to 367 nm of Zn0.96Fe0.04O film. The corresponding wide band gap energy of undoped ZnO film is 3.2986 eV which decreases slightly by 0.0191 eV of Zn0.96Fe0.04O film. The saturation magnetization increases with the increase of Fe concentration. All Fe-doped ZnO films exhibit feromagnetic hysteresis curves which can b...

Nanocrystalline ZnO thin films were prepared by the sol-gel method and annealed at 600 °C by conven- tional (CTA) and rapid thermal annealing (RTA) processes on fluorine-doped tin oxide (FTO)-coated glass substrates for application as the work electrode for a dye-sensitized solar cell (DSSC). ZnO films were crystallized using a con- ventional furnace and the proposed RTA process at anneal- ing rates of 5 °C/min and 600 °C/min, respectively. The ZnO thin films were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM) analyses. Based on the results, the ZnO thin films crystallized by the RTA process presented better crystallization than films crystallized in a conventional furnace. The ZnO films crystallized by RTA showed higher porosity and surface area than those prepared by CTA. The results show that the short-circuit photocur- rent (Jsc) and open-circuit voltage (Voc) values increased from 4.38 mA/cm 2 and 0.55 V for the DSSC with the CTA- derived ZnO films to 5.88 mA/cm 2 and 0.61 V, respectively, for the DSSC containing the RTA-derived ZnO films.

The preferred (002) orientation zinc oxide (ZnO) nanocrystalline thin films have been deposited on FTO-coated glass substrates by sol–gel spin-coating technology and rapid thermal annealing for use in dye-sensitized solar cells (DSSC). The effects of preannealing temperature (100 and 300°C) on the microstructure, morphology and optical properties of ZnO thin films were studied. The ZnO thin films were characterized by X-ray diffraction (XRD), scanning electron microscopic (SEM) and Brunauer–Emmett–Teller (BET) analysis. The photoelectric performance of DSSC was studied by I–V curve and the incident photon-to-current conversion efficiency (IPCE), respectively. From the results, the intensities of (002) peaks of ZnO thin films increases with increasing preannealing temperature from 100°C to 300°C. The increase in pore size and surface area of ZnO films crystallized at the increased preannealing temperature contributed to the improvement on the absorption of N3 dye onto the films, the short-circuit photocurrent (J sc) and open-circuit voltage (V oc) of DSSC. The higher efficiency (η) of 2.5% with J sc and V oc of 8.2 mA/cm2 and 0.64 V, respectively, was obtained by the ZnO film preannealed at 300°C.

Nanocrystalline anatase TiO 2 thin films with different thicknesses (0.5-2.0 μm) have been deposited on ITO-coated glass substrates by a sol-gel method and rapid thermal annealing for application as the work electrode for dye-sensitized solar cells (DSSC). From the results, the increases in thickness of TiO 2 films can increase adsorption of the N3 dye through TiO 2 layers to improve the short-circuit photocurrent (J sc ) and open-circuit voltage (V oc ), respectively. However, the J sc and V oc of DSSC with a TiO 2 film thickness of 2.0 μm (8.5 mA/cm 2 and 0.61 V) are smaller than those of DSSC with a TiO 2 film thickness of 1.5 μm (9.2 mA/cm 2 and 0.62 V). It could be due to the fact that the increased thickness of Ti0 2 thin films also resulted in a decrease in the transmittance of TiO 2 thin films thus reducing the incident light intensity on the N3 dye. An optimum power conversion efficiency (η) of 2.9% was obtained in a DSSC with the TiO 2 film thickness of 1.5 μm.

ZnO-coated TiO2 (ZTO) thin films were deposited on ITO substrates by a sol–gel method for application as the work electrode for dye-sensitized solar cells (DSSCs). The I–V curve and the incident photon-to-current conversion efficiency (IPCE) value of DSSCs for ZTO thin films were studied and compared with single TiO2 films. The results show that the short-circuit photocurrent (J sc) and open-circuit voltage (V oc) values increased from 3.7 mA/cm2 and 0.68 V for the DSSCs with a single TiO2 film to 4.5 mA/cm2 and 0.72 V, respectively, for the DSSCs with a ZTO thin film. It indicated that the DSSCs with a ZTO thin film contributed to provide an inherent energy barrier that suppressed charge recombination significantly. In addition, the higher IPCE value in the ZTO thin film is attributed to the better charge separation by a fast electron transfer process using two semiconductors with different conduction band edges and energy positions.

High-performance pyroelectric infrared (IR) detectors have been fabricated using tantalate-doped lithium niobate LiNb 1 -x Ta x 0 3 (abbreviated as LNT, with x= 0-1.0) thin films deposited on Pt(1 1 11)/TilSiO 2 /Si(100) substrates by diol-based sol-gel processing, in which, tantalate (Ta) is adopted as dopant in lithium niobate. The randomly oriented LNT thin film exhibits a relatively small dielectric constant and a large pyroelectric coefficient. The pyroelectric characteristics of detectors with various tantalate contents, as a function of modulation frequency, were investigated. It was found that LiNb 0,8 Tau 0.2 O 3 had the largest voltage responsivity of 7020 (V/W) at 70 Hz, and a specific detectivity (D*) of 7.76 x 10 7 cm Hz 1/2 /W at 200 Hz. These results indicate that the LNT thin film with x=0.20 is most suitable for application as high-performance pyroelectric thin-film detectors.

TransparentZn1-xMgxO(x=0.01, 0.03, and 0.05) nanocrystalline films were prepared by sol-gel method followed by thermal annealing treatment of 700°C. Mg doping effect on the microstructural and optical properties of theZn1-xMgxOfilms is investigated. From SEM images of all films, mean sizes of uniform spherical grains increase progressively. Pure wurtzite structure is obtained from the results of XRD. Grain sizes increase from 34.7 nm forx=0.01and 37.9 nm forx=0.03to 42.1 nm forx=0.05deduced from the XRD patterns. The photoluminescence spectra of the films show a strong ultraviolet emission and a weak visible light emission peak. The enhancement of ultraviolet emission and reduction of visible emission are observed due to the increase of Mg doping concentration and the corresponding decrease of oxygen vacancy defects. Besides, the characteristics of the dark/photo currents withn-Zn1-xMgxO/n-Siheterojunction are studied for photodetector application.

Tantalum doped TiO2 thin films ((TiO2)1−x (Ta2O5)x, x=0, 0.1%, 0.3%, 0.5%, 0.8%) were prepared on ITO-coated substrates by means of the sol–gel method and spin coating technology followed by rapid thermal annealing treatment (RTA). The effects of various processing parameters, including Ta content (x=0–0.8%) and annealing temperature, on the growth and properties of thin films were investigated. Structural characteristics by X-ray diffraction analysis indicated that the doping of Ta2O5 in the TiO2 without change the anatase structure of TiO2 thin films. The optical transmittance of (TiO2)1−x(Ta2O5)x thin films decrease from 50% down to 20% with increasing the Ta2O5 concentrations from x=0.00 to x=0.8%. The absorption coefficient shows energy gap were decreased with increasing Ta2O5 content from 2.932 eV for x=0.00 to 2.717 eV for x=0.8%. Doping TiO2 with Ta2O5 can lower its band gap and shift its optical response to the visible region.

Four p–i–n GaInP solar cells were grown by metal organic chemical vapor deposition (MOCVD) with different intrinsic layer thicknesses from 0.25 to 1 µm. A series of optical measurements, including electroreflectance (ER), photoluminescence (PL), electric luminescence (EL), and photocurrent (PC) measurements, have been performed to study the built-in electric field effect and to determine the suitable thickness of an intrinsic layer. The PL and EL spectra reflected the crystal quality of the GaInP layers. Furthermore, from the obtained ER spectrum, the built-in electric field in the intrinsic layer can be revealed. From the PC spectra under various bias voltages, the effect of built-in electric fields on the collection of photogenerated carriers has been studied.

The novel pyroelectric infrared (IR) detectors have been fabricated using the Polyvinylidene Fluoride (PVDF)/Lead Titanate (PT) pyroelectric bilayer thin films which were deposited onto Pt(111)/SiO/sub 2//Si(100) substrates by a sol-gel process. The ceramic/polymer structure was constructed of the randomly oriented polycrystalline PT film(/spl sim/1 /spl mu/m) heated at 700/spl deg/C for 1 h and the /spl beta/-phase PVDF film crystallized at 65/spl deg/C for 2 h. The effects of PVDF thin film thickness (100/spl sim/580 nm) on the pyroelectric response of IR detectors were studied. The results show that the depositions of PVDF thin films onto the PT films will cause the leakage current (J) of the detectors decrease from 6.37 /spl times/ 10/sup -7/ A/cm/sup 2/ to 3.86 /spl times/ 10/sup -7/ A/cm/sup 2/. The specific detectivity (D*) measured at 100 Hz decreased from 2.72 /spl times/ 10/sup -7/ cm/spl middot/Hz/sup 1/2//W for detector without PVDF to 1.71 /spl times/ 10/sup -7/ cm/spl middot/Hz/sup 1/2//W for detector with PVDF thickness of 580 nm. By optimizing the ratio of the specific detectivity (D*) to leakage current, D*/J, the detector with PVDF thickness of 295 nm exhibits the best performance.

La-modified lead titanate (PLT) thin films were deposited on Pt/SiO/sub 2//Si substrates by spin coating with sol-gel processing. 1,3-propandiol was used as solvent to minimize the number of cycles of spin coating and drying processes to obtain the desired thickness of high quality thin film. The randomly oriented PLT thin film exhibits a relatively small dielectric constant and a large pyroelectric coefficient without poling treatment. Pyroelectric infrared (IR) detectors have been fabricated without the back side etching process The pyroelectric characteristics of point detectors with various La contents as a function of modulation frequency are compared. It was found that the PLT(10) detector has a large voltage responsivity of 3330 (V/W) at 20 Hz. The specific detectivity (D*) at 100 Hz is 6.2/spl times/10/sup 7/ cmHz/sup / 1/2 //W. The results showed that Pb/sub 1-x/La/sub x/Ti/sub 1-x/4/O/sub 3/ thin film with x=0.10 [PLT(10)] was most suitable for use as a pyroelectric IR detector.

High-performance pyroelectric infrared (IR) detectors have been fabricated without the back side etching process usingMg-modified lead titanate (Pb1MgTiO3) thin films. PMT thin films were deposited on (1 1 1)-oriented Pt thin film onSi02/Si(100) substrates by a diol-based sol-gel process. The randomly oriented PMT thin film exhibits a relatively small di-electric constant and a large pyroelectric coefficient without poling treatment. The pyroelectric characteristics of point de-tectors with various Mg contents as a function of modulation frequency are compared. It was found that the PMT(6) thinfilm detector has a large voltage responsivity of 5280 (V/W) at 20 Hz. The specific detectivity (D*) at 100 Hz is 5. 12x iO cmHz"2/W. The results showed that Pb1MgTiO3 thin film with x0.06 [PMT(6)] was most suitable for use as a pyroelectric IR detector.Keywords: sol-gel, PMT, pyroelectric, JR detector, voltage responsivity, specific detectivity 1. INTRODUCTION Pyroelectric detectors are an important class of thermal transducers, which are based on the temperature-induced spon-taneous polarization change exhibited by certain crystals. Researches on ferroelectric materials for the pyroelectric detectionof infrared (IR) radiation have become an attractive technological activity in the last few years. 1-8.

Lithium tantalite (LiTaO3) thin films (∼0.5 μm ) have been successfully deposited on Pt (111)/ SiO 2 / Si (1 0 0) substrates by means of sol–gel spin-coating technology. Figures of merit for infrared detector were studied for the LiTaO3 thin films. There exists high figures of merit Fv of 2.1×10 −10 C cm/J and Fm of 2.4×10 −8 C cm/J because of the relative low dielectric constant (er) of 35 and high pyroelectric coefficient (γ) of 4.0×10 −8 C/cm 2 K of the films. The pyroelectric infrared detector fabricated by the LiTaO3 thin film exhibits a voltage reponsivity Rv of 4584 V/W at 20 Hz and a high specific detectivity D ∗ of 4.23×10 7 cm Hz 1/2 / W at 100 Hz .

Aligned ZnO nanowires with different lengths (1 to approximately 4 μm) have been deposited on indium titanium oxide-coated glass substrates by using the solution phase deposition method for application as a work electrode in dye-sensitized solar cells (DSSC). From the results, the increases in length of zinc oxide (ZnO) nanowires can increase adsorption of the N3 dye through ZnO nanowires to improve the short-circuit photocurrent (Jsc) and open-circuit voltage (Voc), respectively. However, the Jsc and Voc values of DSSC with ZnO nanowires length of 4.0 μm (4.8 mA/cm2 and 0.58 V) are smaller than those of DSSC with ZnO nanowires length of 3.0 μm (5.6 mA/cm2 and 0.62 V). It could be due to the increased length of ZnO nanowires also resulted in a decrease in the transmittance of ZnO nanowires thus reducing the incident light intensity on the N3 dye. Optimum power conversion efficiency (η) of 1.49% was obtained in a DSSC with the ZnO nanowires length of 3 μm.

Calcium-modified lead titanate (PCT) thin film pyroelectric infrared (IR) detectors were fabricated on Pt(111)/SiO2/Si(100) substrates using a diol-based sol–gel process. The randomly oriented PCT thin film, which has not undergone the poling treatment, exhibits a relatively small dielectric constant and a large pyroelectric coefficient. The pyroelectric properties of PCT thin film point detectors with various Ca contents on modulation frequency are measured and compared. The optimized composition of PCT thin film IR detectors was found to be the PCT(25), which exhibits a large voltage responsivity of 4533 (V/W) at 20 Hz and a specific detectivity (D *) of 6.45×107 cmHz1/2/W at 100 Hz. The results show that Pb1-x Ca x TiO3 thin film with x = 0.25 [PCT(25)] was most suitable for application to the pyroelectric thin film IR detector.

One-dimensional pure zinc oxide (ZnO) and Y-doped ZnO nanorod arrays have been successfully fabricated on the silicon substrate for comparison by a simple hydrothermal process at the low temperature of 90°C. The Y-doped nanorods exhibit the same c-axis-oriented wurtzite hexagonal structure as pure ZnO nanorods. Based on the results of photoluminescence, an enhancement of defect-induced green-yellow visible emission is observed for the Y-doped ZnO nanorods. The decrease of E2(H) mode intensity and increase of E1(LO) mode intensity examined by the Raman spectrum also indicate the increase of defects for the Y-doped ZnO nanorods. As compared to pure ZnO nanorods, Y-doped ZnO nanorods show a remarked increase of saturation magnetization. The combination of visible photoluminescence and ferromagnetism measurement results indicates the increase of oxygen defects due to the Y doping which plays a crucial role in the optical and magnetic performances of the ZnO nanorods.