{"title":"Carrier and phonon dynamics in GaInNAs","authors":"Fa-Jun Ma","doi":"10.1117/12.888156","DOIUrl":"https://doi.org/10.1117/12.888156","url":null,"abstract":"Degenerate pump-probe experiments have been performed on the dynamics of carrier and phonon in GaInNAs thin films. The time-resolved differential transmission shows a negative value, indicating photoinduced absorption from the trap states. After the negative minimum the differential transmission recovers to zero with a long time constant. Rate equation has been employed to simulate the carrier dynamics. The calculations fit the experimental differential transmission very well. The extracted time constants show that the carriers in the trap states of GaInNAs decay to equilibrium with a single time constant of 1.2 ns. An obvious modulation of the transmission signal has been observed superimposing on the photoinduced absorption. Such a modulation is found at a low frequency of 380 GHz by Fourier transform. This low frequency oscillation might be attributed to coherent longitudinal acoustic (LA) phonon.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122496514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optical spectroscopy of organic semiconductor monolayers","authors":"R. He, N. G. Tassi, G. Blanchet, A. Pinczuk","doi":"10.1117/12.888197","DOIUrl":"https://doi.org/10.1117/12.888197","url":null,"abstract":"Growing interest in organic molecular semiconductors is stimulated by their promising applications in flexible devices. Pentacene is a benchmark organic semiconductor material because of its potential applications in high mobility thin film transistors and optoelectronic devices. Highly uniform monolayers of pentacene grown on polymeric substrate of poly alpha-methylstyrene exhibit sharp and intense free exciton (FE) luminescence at low temperatures. The FE emission displays characteristic intensity that grows quadratically with the number of layers. Large enhancements of Raman scattering intensities at the FE resonance enable the first observations of low-lying lattice vibrational modes in films reaching the single monolayer level. The low-lying modes exhibit characteristic changes when going from a single monolayer to two layers, revealing that a phase akin to a thin film phase of pentacene already emerges in structures of only two monolayers. A simple analysis of mode splittings offers estimates of the strength of inter-layer interactions. The results demonstrate novel venues for ultra-thin film characterization and studies of interface effects in organic molecular semiconductor structures.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125372462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jianhua Ma, Yan Liang, Xiaojing Zhu, Jinchun Jiang, Shanli Wang, N. Yao, J. Chu
{"title":"Preparation and properties of ZnO:Mo thin films deposited by RF magnetron sputtering","authors":"Jianhua Ma, Yan Liang, Xiaojing Zhu, Jinchun Jiang, Shanli Wang, N. Yao, J. Chu","doi":"10.1117/12.888246","DOIUrl":"https://doi.org/10.1117/12.888246","url":null,"abstract":"Mo doped ZnO thin films (ZnO:Mo, MZO) were prepared on quartz glass substrates by RF magnetron sputtering at the lower substrate temperatures (room temperature (RT) and 100°C). Their structural, electrical and optical properties were studied by X-ray diffractometry (XRD), four probe technique, Hall measurement, and UV-VIS-NIR spectrophotometer, respectively. XRD showed that the resultant films were wurtzite structure with c-axis preferential orientation. As the substrate temperatures increasing, the thickness of the film increased and the crystallinity became better. The resistivity of the films were 3.44x10-3 Ω•cm and 3.31x10-3 Ω•cm for the films deposited at RT and 100°C, respectively. The corresponding average transmittance in visible and near IR region (400-1100nm) was 81.7 % and 74.5 %, respectively. In addition, for the film deposited at 100°C, the refractive index (n) and band gap (Eg) were obtained by fitting the transmittance spectra and discussed.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121423912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hua-song Liu, D. Hou, Zhanshan Wang, Yi-qin Ji, Yongkai Fan, R. Fan
{"title":"Comparison of envelope method and full spectra fitting method for determination of optical constants of thin films","authors":"Hua-song Liu, D. Hou, Zhanshan Wang, Yi-qin Ji, Yongkai Fan, R. Fan","doi":"10.1117/12.888438","DOIUrl":"https://doi.org/10.1117/12.888438","url":null,"abstract":"Transmittance envelope of the thin film-substrate system and full spectra fitting method are two important methods to determine the optical constants of the optical thin films. Ion beam sputtering deposition technique was used to manufacture HfO2 single layer thin film onto fused silica substrate. The two methods were used to calculate optical constants of the HfO2 thin film in the extreme wavelength, and the Cauchy dispersion model was used to fit the optical constants in wavelength region from 300 nm to 1000 nm. Using the thin-film optical constants obtained above we calculated the spectral transmittance and judged the inversion accuracy of the two methods. The results show that the accuracy of the full spectra fitting method is higher than the transmittance spectra envelope. The similarities and differences between the two methods are also discussed in this paper.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123777116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Linlin Tian, L. Yao, Shuo Wang, Ruiqing Xu, Lin Li, X. Fang
{"title":"FTIR and optical transmittance investigation of hydrophobic SiO2-Al2O3 composite films","authors":"Linlin Tian, L. Yao, Shuo Wang, Ruiqing Xu, Lin Li, X. Fang","doi":"10.1117/12.888185","DOIUrl":"https://doi.org/10.1117/12.888185","url":null,"abstract":"The hydrophobic and transparent SiO2-Al2O3 composite films were prepared by the sol-gel process using tetraethoxysliane (TEOS) and aluminium isopropoxide Al(C3H7O)3 as precursors, methyltriethoxysilane (MTES) and cetyltrimethylammonium bromide (CTAB) as chemical modifier and surfactant respectively. Optimum condition for the SiO2-Al2O3 nano-composite films with hydrophobic and transparent as well as mechanical properties simultaneously is investigated. It was found that the Si/Al molar ratio should be 1:0.008 and the calcined temperature should be 300°C. The infrared spectra of the films indicated that the hydrophobic surface of the film was due by the introduction of the methyl groups.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"7995 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130448614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Juan Qin, Ai-min Li, Zhenyi Chen, Lei Zhao, Xiao-lei Zhang, Wei-min Shi, Guang-pu Wei
{"title":"Silicon nitride films as the diffusion barriers for flexible CIGS thin film solar cells","authors":"Juan Qin, Ai-min Li, Zhenyi Chen, Lei Zhao, Xiao-lei Zhang, Wei-min Shi, Guang-pu Wei","doi":"10.1117/12.888292","DOIUrl":"https://doi.org/10.1117/12.888292","url":null,"abstract":"Impurity diffusion from the flexible metal substrate into CIGS absorption layer can remarkably reduce cell performance comparing with conventional glass substrate. A diffusion barrier layer lying between the metal substrate and Mo backcontact layer is required to prevent this spread of impurities. In this paper, a set of Si3+xN4-x barrier layers are grown on stainless steel sheets and alloy foils by the magnetron sputtering under different conditions. The morphological, structural and electrical properties of the samples are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and I-V measurements. Our results indirectly support good blocking effect of Si3+xN4-x barrier to the metal impurities from the stainless steel substrate.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130499667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Influence of ion-doping on the photoelectric properties of mesoporous ZnO thin films","authors":"Linyu Li, Yue Shen, Qishuang Wu, M. Cao, Feng Gu, Jian-cheng Zhang","doi":"10.1117/12.888217","DOIUrl":"https://doi.org/10.1117/12.888217","url":null,"abstract":"Sn, Al, Y-doped mesoporous ZnO(doping with 5 at.%) thin films (M-ZnO-5%X, X= (Sn, Al, Y))with regular mesoporous structures were successfully prepared through sol-gel and spin-coating methods, as evidenced from small angle X-ray diffraction (SAXRD) and scanning electron microscopy (SEM). The diameter/d value is about 8 nm calculated by Bragg equation. Influences of ion-doping on the photoluminescence spectra of mesoporous ZnO thin films were investigated. The energy gaps of Y, Al, Sn-doped mesoporous ZnO increase from 3.0 eV (the energy gap of undoped ZnO thin film) to 3.05, 3.08 and 3.15 eV, respectively. Dye-sensitized solar cells (DSSCs) based on Sn, Al, Y-doped ZnO photoelectrodes were structured and the properties of the cells were studied. Compared with undoped ZnO film, M-ZnO-5%Sn film showed higher solar-to-electric conversion efficiency, which may come from the broader absorbance.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131870660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Influence of Mg-doped on the Microstructure and Oxygen Storage Capacity of Ce0.5Zr0.5O2","authors":"Y. Yao, Dongmei Li, Tiansheng Xu, T. Fu","doi":"10.1117/12.888176","DOIUrl":"https://doi.org/10.1117/12.888176","url":null,"abstract":"Mg-doped Ce0.5Zr0.5O2 nanocrystalline powders were prepared via hydrothermal method through homogeneous nucleation at 453K followed by calcinations at 673K. The effect of Mg-doping concentrations on the structure and performances of Ce0.5Zr0.5O2 was studied. The results showed that Mg-doped Ce0.5Zr0.5O2 was a single fluorite-type phase and the size was about 4nm. The introduction Mg into the Ce0.5Zr0.5O2 lattice limited the mobility of oxygen and made the specific surface area and oxygen storage capacity(OSC) declined at doping constant less than 4mol%; as more than 4mol%, a segregation of Mg was dispersed on surface of Ce0.5Zr0.5O2 and improved the thermal stability of surface, thus enhanced the OSC performance.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130733855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fangfang Wang, Jingtao Zhu, M. Tan, Li Jiang, Zhanshan Wang
{"title":"New design concept of hard x-ray supermirrors for astronomical x-ray telescopes","authors":"Fangfang Wang, Jingtao Zhu, M. Tan, Li Jiang, Zhanshan Wang","doi":"10.1117/12.887371","DOIUrl":"https://doi.org/10.1117/12.887371","url":null,"abstract":"A numerical and analysis method for optimizing multilayer supermirrors is developed based on the combination of the power-law method and the local optimization method of simplex algorithm. The parameters in the power-law formula are optimized by genetic algorithm. This allows a global minimization of the merit function and a many-fold decrease of the computing time. Several groups of X-ray supermirrors with the energy extended to 30 keV are successfully designed using this optimization method for a hard X-ray telescope. Tungsten and boron carbide are chosen as the multilayer materials. High reflectivity and high effective area are obtained, indicating that this numerical and analysis method is an effective tool to design hard X-ray supermirrors.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117096879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Preparation of polycrystalline silicon thin films on glass by aluminiuminduced crystallization","authors":"Jieli Chen, Wei-min Shi, Jing Jin, Weiguang Yang, Y. Liao, Yueyang Xu, Linjun Wang, Guang-pu Wei","doi":"10.1117/12.888230","DOIUrl":"https://doi.org/10.1117/12.888230","url":null,"abstract":"Polycrystalline silicon (p-Si) is well-known as the high-efficency, low-cost, and most ideal material for manufacturing photovoltaic devices. In recent years, excimer-laser annealing (ELA), metal-induced crystallization (MIC) and solidphase crystallization (SPC) methods are employed to crystallize amorphous silicon (a-Si). In this paper, a cheap metal induced crystallization method of fabricating p-Si thin films on an ordinary glass substrate was investigated. In this synthesis process, a-Si thin film has been deposited onto glass substrates by Plasma Enhanced Chemical Vapor Deposition (PECVD), and p-Si thin films have been fabricated by aluminium-induced crystallization (AIC) under nitrogen ambient. The effects of annealing time, annealing temperature on the crystallization of a-Si were investigated by X-ray diffraction (XRD) technique. Our results indicate that annealing temperature over 300°C is necessary for crystallization of a-Si which preferred to orientation crystalline Si(111) and this preferred orientation becomes more obvious as increasing of annealing time and annealing temperature. Meanwhile, the longer annealing time can produce more a-Si crystallize completely under same aluminium thickness and annealing temperature.","PeriodicalId":316559,"journal":{"name":"International Conference on Thin Film Physics and Applications","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124652925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}