In order to control nanoimprint lithography (NIL) processes for achieving good fidelity, the fast, low-cost, non-destructive and accurate measurement of geometric parameters of templates and imprinted grating structures is of great importance. Compared with conventional ellipsometric scatterometry, which only obtains two ellipsometric angles and has 2 changeable measurement conditions, i.e., the wavelength and the incidence angle, Mueller matrix ellipsometry (MME) can provide up to 16 quantities of a 4×4 Mueller matrix in each measurement with 3 changeable measurement conditions, i.e., the wavelength, the incidence angle and the azimuthal angle. Therefore, MME can acquire much more useful information about the sample. It is expected that much more accurate measurements of nanostructures can be achieved by choosing proper measurement configurations and completely using the rich information hidden in the measured Mueller matrices. Accordingly, the templates and imprinted grating structures in NIL processes are measured using an in-house developed Mueller matrix ellipsometer. We experimentally demonstrate that more accurate quantification of geometric parameters, such as line width, line height, sidewall angle and residual layer thickness, can be achieved by performing MME measurements in the optimal configuration and meanwhile by incorporating depolarization effects into the optical model. Moreover, as for the imprinted grating structures, the residual layer thickness variation over the illumination spot can also be directly determined by MME. The comparison between MME-extracted template and imprinted resist profiles also indicates an excellent fidelity of the nanoimprint pattern transfer process.

The silicon nanometer structure grating and the photoresist nanometer structure grating were prepared. A fitting model was built on the new self-developed generalized ellipsometer. Then, the gratings was tested and fitted. Results proved that the machine could work well in nondestructive test of nano grating. Under the condition of the incident angle of 60 and the azimuth angle of 75, the measurement accuracy can be up to 99.97% for the three-dimensional morphology parameters such as key dimension and sidewall angle and so on, and the maximum error is less than 1%. This method is significant for the nondestructive test.

Ba0.6Sr0.4TiO3 (BST) nanotubes are fabricated successfully by sol-sel method with the through-hole anodic aluminum oxide (AAO) template for the first time so far as we know. This fabrication method is easy to realize at low cost because the through-hole AAO template and the BST sol can be acquired easily at low cost, so this is very valuable in the fabrication of other similar nanostructures. First, the steady BST sol is prepared and the well aligned through-hole anodic aluminum oxide template is fabricated by a two-step anodization method; second, the BST sol is introduced into the ordered nanohole arrays of the through-hole AAO template by dipping and spinning; and finally, the samples are fired in air at 650℃ for 1 h to get BST nanotubes. X ray diffraction (XRD) patterns reveal that the BST nanotubes are of cubic perovskite structures, and grow mainly along [110] crystal orientation. Scanning electron microscope (SEM) results show that the thickness and pore size of the through-hole AAO template are about 16 μm and 75 nm, respectively. The length, external and inner diameters of the BST nanotubes are about 16 μm, 75 nm and 50 nm, respectively. Measurements of BST nanotubes give results highly matched with that of the through-hole AAO template. Fourier transform infrared spectroscopy (FTIR) results shows that in the 1350-1650 cm-1 waveband, the composite structure of AAO/BST nanotubes has two obvious absorption peaks which are respectively at 1470 and 1550 cm-1, while the BST film does not have; the absorption property of the composite structure is about two times of the pure through-hole AAO membrane. Finally, the possible reasons of this phenomenon about infrared absorption are discussed.

Patterned Sapphire Substrate (PSS) which can reduce the density of threading dislocation and enhance the effect of scattering is widely used to fabricate high-power Light-Emitting-Diode (LED) chip. In this paper, the finite- difference time-domain (FDTD) method was used to simulate and analyze the light extraction efficiency (LEE) of GaN-based micro-scale and nano-scale patterned sapphire substrates LED. The results show that the nano-patterned sapphire substrate (NPSS) has a significantly better LEE than that of micro-patterned sapphire substrate (MPSS). And in NPSS, the LEE of the pillar structure improveed 96.6% comparing to other nano-patterned structures. Large areas of table-like nano-sapphire patterned substrates are successfully prepared through soft embossing technology. The photoluminescence (PL) of the LED grown on table-like nano-sapphire patterned substrates is 8 times stronger than that of the LED grown on the unpatterned sapphire wafers

Amorphous zinc oxide thin film was prepared through Sol-Gel method using deep-ultraviolet photochemical activation instead of high temperature annealing. The XRD patterns showed that the zinc oxide film was amorphous. XPS analysis showed that the film was mainly composed of ZnO. The Al top electrodes were deposited on irradiated thin film by DC magnetron sputtering to get Al/a-ZnO/FTO structured device. The influence of deep-ultraviolet irradiation time on switching properties was investigated to understand the mechanism of deep-ultraviolet irradiation. The results illustrate that the device after sufficient irradiation (12 h) has bipolar resistive switching property. The distribution of threshold voltage is very concentrated (-3.7 V