This paper experimentally and theoretically investigates the effect of the underlayer medium on tuning of the surface plasmon resonance （SPR） wavelength of silver island films, and the effect of substrate temperatur...This paper experimentally and theoretically investigates the effect of the underlayer medium on tuning of the surface plasmon resonance （SPR） wavelength of silver island films, and the effect of substrate temperature on the morphologies and optical properties of the films. From the absorption spectra of single Ag with various thickness and overcoated （Ag/TiO2） films deposited on glass substrates at various substrate temperatures by RF magnetron sputtering, we demonstrate that the surface plasmon resonance wavelength can be made tunable by changing the underlayer medium, the thickness of metal layer and the substrate temperature. By varying substrate temperatures, the interparticle coupling effects on plasmon resonances of nanosilver particles enhance as the spacing between the particles reduces. When the substrate temperature is up to 500 ℃, the absorption peak decreases sharply and shifts to shorter wavelength side due to the severe coalescence between silver islands in the film.展开更多
Due to their particular optical characteristics,metallic island films have the potential to significantly increase the energy conversion efficiency of solar cell.We experimentally and theoretically investigated the ef...Due to their particular optical characteristics,metallic island films have the potential to significantly increase the energy conversion efficiency of solar cell.We experimentally and theoretically investigated the effect of substrate temperature on the morphologies and optical properties of the silver island films.At low temperature,below 300 ℃,as the substrate temperature increases.Compared to the films prepared at room temperature,the sizes of nanoparticles decrease and the Absorption peaks shift to shorter wavelength accompanied by an increase density resulting in a 150% Absorption efficiency.As the substrate temperature goes up to 300 ℃,nanoparticles with larger in-plan(X-Y)dimensions are formed,the number density decreases and the Absorption peaks redshift but the Absorption efficiency is still 10% higher.Numerical simulation reveals that these behaviors are a consequence of morphologies transformation.展开更多
In order to investigate the morphology change of Ag nano-particles/island film with the sputtering time and annealing temperature,Ag nano-particles/island films were sputtered on the silicon wafers by radio-frequency(...In order to investigate the morphology change of Ag nano-particles/island film with the sputtering time and annealing temperature,Ag nano-particles/island films were sputtered on the silicon wafers by radio-frequency(RF)magnetron sputtering.Ag nano-particles/islands films were sputtered on Si wafer with different time.After sputtering,the samples with Ag nano-particles/islands films were annealed at 100,200 and 400 o C for 1 h,respectively.Raman spectrum was employed to examine the phase stability of Ag particles/island film after annealed at 400 o C for 1h.The result showed that the Raman spectrum peak of Ag particles/island film with annealed at 400 o C was similar to that of pure Ag.Scanning electron microscope(SEM)was used to test the microstructures and morphology of the films with different condition.To further study the morphology change,atomic force microscope(AFM)was used to test surface morphology of the Ag particles/islands films.The SEM and AFM results showed that the morphology of Ag nano-particles/island films were different with the increasing sputtering time.Ag particles went through a dramatic change on the Si wafer surface,when sputtering time changed from 3 to 60 s,Ag particles diffused and agglomerated with the annealing temperature increasing.展开更多
基金Project supported by the Distinguished Youth Foundation of Hunan Province,China (Grant No. 03JJY1008)the Science Foundation for Post-doctorate of China,(Grant No. 2004035083)the Natural Science Foundation of Hunan Province,China(Grant No. 06JJ2034)
文摘This paper experimentally and theoretically investigates the effect of the underlayer medium on tuning of the surface plasmon resonance （SPR） wavelength of silver island films, and the effect of substrate temperature on the morphologies and optical properties of the films. From the absorption spectra of single Ag with various thickness and overcoated （Ag/TiO2） films deposited on glass substrates at various substrate temperatures by RF magnetron sputtering, we demonstrate that the surface plasmon resonance wavelength can be made tunable by changing the underlayer medium, the thickness of metal layer and the substrate temperature. By varying substrate temperatures, the interparticle coupling effects on plasmon resonances of nanosilver particles enhance as the spacing between the particles reduces. When the substrate temperature is up to 500 ℃, the absorption peak decreases sharply and shifts to shorter wavelength side due to the severe coalescence between silver islands in the film.
基金The Distinguished Youth Foundation of Hunan Province(03JJY1008)The Natural Science Foundation of Hunan Province(06JJ2034)
文摘Due to their particular optical characteristics,metallic island films have the potential to significantly increase the energy conversion efficiency of solar cell.We experimentally and theoretically investigated the effect of substrate temperature on the morphologies and optical properties of the silver island films.At low temperature,below 300 ℃,as the substrate temperature increases.Compared to the films prepared at room temperature,the sizes of nanoparticles decrease and the Absorption peaks shift to shorter wavelength accompanied by an increase density resulting in a 150% Absorption efficiency.As the substrate temperature goes up to 300 ℃,nanoparticles with larger in-plan(X-Y)dimensions are formed,the number density decreases and the Absorption peaks redshift but the Absorption efficiency is still 10% higher.Numerical simulation reveals that these behaviors are a consequence of morphologies transformation.
基金Supported by"the Fundamental Research Funds for the Central Universities"
文摘In order to investigate the morphology change of Ag nano-particles/island film with the sputtering time and annealing temperature,Ag nano-particles/island films were sputtered on the silicon wafers by radio-frequency(RF)magnetron sputtering.Ag nano-particles/islands films were sputtered on Si wafer with different time.After sputtering,the samples with Ag nano-particles/islands films were annealed at 100,200 and 400 o C for 1 h,respectively.Raman spectrum was employed to examine the phase stability of Ag particles/island film after annealed at 400 o C for 1h.The result showed that the Raman spectrum peak of Ag particles/island film with annealed at 400 o C was similar to that of pure Ag.Scanning electron microscope(SEM)was used to test the microstructures and morphology of the films with different condition.To further study the morphology change,atomic force microscope(AFM)was used to test surface morphology of the Ag particles/islands films.The SEM and AFM results showed that the morphology of Ag nano-particles/island films were different with the increasing sputtering time.Ag particles went through a dramatic change on the Si wafer surface,when sputtering time changed from 3 to 60 s,Ag particles diffused and agglomerated with the annealing temperature increasing.
