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To enlarge the grain size and decrease the effect of the defect between the grain boundaries on a p-Si film transistor,a phase modulated excimer laser crystallization technique is used to fabricate the uniform p-Si film with a large grain size.First,an energy window for super lateral growth is determined by measuring the grain size of p-Si film fabricated with different laser energy intensities.Then,the spatial distribution of the input laser is modulated by a phase mask with a period of 1 073 nm and an artificially controlled lateral temperature gradient is induced on the a-Si film,which leads the a-Si to be melten and crystallized into p-Si grains by super lateral growth.Finally,the characteristics of the prepared p-Si film are measured and compared with those of the a-Si film and the p-Si film fabricated by super lateral growth technique.The results show that the grain size of the p-Si film is 228.24 nm,which is ten times of that fabricated by super lateral growth under the same processing parameters;the electrical resistivity of the prepared sample is 18.9 Ω·m,which is lower by an order magnitude than that prepared by super lateral growth.Furthermore,the distribution of the grain is more uniform than that fabricated by other techniques.The reported technique can increase the electrical characteristics of the p-Si film greatly and is suitable for the fabrication of high quality p-Si devices.

A high precision temperature calculation method of fiber-optic distributed temperature sensing system based on iteration technique is introduced.Compared with the traditional calculation methods,this iteration-based method further corrects the attenuation coefficient difference of the Raman anti-stokes wavelength and stokes wavelength in optical fiber which is temperature-sensitive,thus increases the precision of temperature measurement.It especially works well with the measurements of normal-distance,complex temperature distribution fields.The iterative formula is established by theoretical analysis,the corresponding fiber parameters are pre-measured,by programming on data processing module of the sensing system.The result shows great accordance between calculation and actual temperature distribution within the range from 0 to 90℃ along a whole fiber of 5 km.

The carrier density mobility in organic electron transporting semiconductor is very low compared with the inorganic semiconductor,which affects the efficiency and luminance of Organic Light-emitting Devices(OLEDs).To improve the performance of OLED,the electron injecting and transporting ability should be enhanced,and n-type electrically doping can enhance the electron transporting ability of the orangic materials.Li3N was used as n-type dopant and Alq3∶Li3N doped layer was used as the electron injecting layer for OLED.As a result,the performance of OLED were improved.The optimal doping concentration and the thickness were 5% and 10 nm,respectively.Because Li3N is stable in the air and can decomposite to Li atoms and nitrogen at a low temperature and pressure,the disadvantage can be avoided of the effecting of moisture and oxygen to the metal dopant such as Li and Cs.The research result is also helpful to the preserve and doping process.