Highly efficient Si 3 N 4 ceramic planar membrane for water desalination process using membrane distillation was prepared by the dual-layer phase inversion tape casting and sintering method. In comparison with typical phase inversion tape casting method, the green tape was formed using Si 3 N 4 slurry on the top and graphite slurry on the bottom. After consuming away the graphite structure, a ceramic membrane consisting of a two-layered structure (skin and finger-like layers) was obtained. The skin layer was relatively tight, and thus could act as a functional layer for separation, while the finger-like layer contained straight open pores with a diameter of 100 μm, acting as a support with low transport resistance. For comparison, typical Si 3 N 4 ceramic membrane was fabricated by phase inversion technique without graphite substrate, resulting in a three-layered structure (skin, finger-like, and sponge layers). After membrane modification from hydrophilic to hydrophobic with polymer derived nanoparticle method, the water desalination performance of the membranes was tested using the sweeping gas membrane distillation (SGMD) with different NaCl feed solutions. With the increase of salt content from 4 to 12 wt%, the water flux decreased slightly while rejection rate maintained over 99.99%. Comparing with typical three-layered Si 3 N 4 membrane, an excellent water flux enhancement of over 83% was resulted and the rejection rate remained over 99.99%.

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ZnO thin films are deposited on Al/Si substrates by the pulsed laser deposition (PLD) method. The XRD and SEM images of films are examined. Highly c-axis oriented ZnO thin films which have uniform compact surface morphology are fabricated. The size of surface grains is about 30 nm. The Schottky barrier ultraviolet detectors with silver Schottky contacts are made on ZnO thin films. The current-voltage characteristics are measured. The ideality contact factor between Ag and ZnO film is 1.22, while the barrier height is 0.908 e V. After annealing at 600 o C for 2h, the ideality factor is 1.18 and the barrier height is 0.988 eV. With the illumination of 325 nm wavelength UV-light, the photocurrent-to-dark current ratios before and after annealing are 140.4 and 138.4 biased at 5 V, respectively. The photocurrents increase more than two orders of magnitude over the dark currents.Zinc oxide (ZnO) is a wide direct bandgap semiconductor of II-VI group materials. The wide bandgap energy of 3.37 eV at room temperature and large exciton-binding energy of 60 meV make ZnO the good physical and chemical properties. In the applications of ZnO [1,2] , it is a key point that high-quality metal-ZnO contact could be successfully fabricated on ZnO thin films. Using the Schottky contacts we can fabricate ZnO-based Schottky detectors with metal-semiconductor-metal (MSM) structure [3][4][5] . At present, the growth of p-ZnO through doping is still so difficult that we cannot fabricate good quality p-n junction. So MSM structure is appropriate for ZnO-based UV detectors. Thus the study of ZnO-based Schottky contacts has practical significance.In this paper, the mainly experiment equipment is pulse laser deposition (PLD) system (as shown in Fig.1). In experiment, four targets are metal Al, ZnO doping Al (AZO, the mount of Al is 3% in mass), ZnO, and metal Ag. The purities of all the targets are better than 99.99%. The substrates are n-Si (111) with 450 m thickness. Before substrates are put into vacuum chamber, the pretreatment program is as follows: (1) silicon chips are rinsed using deionized water; (2) they are utrasonic cleaned for 10 minutes using acetone and ethanol respectively; (3) substrates are rinsed using deionized water repeatedly; (4) silicon chips are etched in 5% HF for 5 minutes to remove surface oxidation layer; (5) substrates are soaked for 10 minutes in deionized water; then high-purity N 2 is used to blow drying chips and the substrates are put into vacuum chamber for 5 minutes. During experiments, the background vacuum keeps better than 2×10 -5 Pa. 500 nm thickness Al thin films are deposited on silicon substrates at 200 o C as ohmic electrodes. At the same time, the aluminum films are also buffer layer of ZnO growth [6] . As the difference of thermal expansion coefficient between ZnO and silicon is very large, which are 4.75×10 -6 K -1 and 2.6×10 -6 K -1 respectively, ZnO thin film will shrink more than silicon substrates when the temperature declines from growth temperature to room temperature. Large numbers of cra...