通过热丝化学气相沉积法(Hot Wire Chemical Vapor Deposition,HWCVD),采用间歇供应硅烷气体,持续通入氢气的方式控制硅薄膜的生长,发现该方法在有机衬底上生长的薄膜结构为多晶相占主导地位。此外,研究了不同间歇周期条件下薄膜的形貌...通过热丝化学气相沉积法(Hot Wire Chemical Vapor Deposition,HWCVD),采用间歇供应硅烷气体,持续通入氢气的方式控制硅薄膜的生长,发现该方法在有机衬底上生长的薄膜结构为多晶相占主导地位。此外,研究了不同间歇周期条件下薄膜的形貌和结构,并对生长机理进行了解释和讨论。展开更多
Selected area laser-crystallized polycrystalline silicon （p-Si） thin films were prepared by the third harmonics （355 nm wavelength） generated by a solid-state pulsed Nd：YAG laser. Surface morphologies of 400 nm t...Selected area laser-crystallized polycrystalline silicon （p-Si） thin films were prepared by the third harmonics （355 nm wavelength） generated by a solid-state pulsed Nd：YAG laser. Surface morphologies of 400 nm thick films after laser irradiation were analyzed. Raman spectra show that film crystallinity is improved with in- crease of laser energy. The optimum laser energy density is sensitive to the film thickness. The laser energy density for efficiently crystallizing amorphous silicon films is between 440-634 mJ/cm^2 for 300 nm thick films and between 777-993 mJ/cm^2 for 400 nm thick films. The optimized laser energy density is 634, 975 and 1571 mJ/cm^2 for 300, 400 and 500 nm thick films, respectively.展开更多
Polycrystalline silicon(poly-Si) thin films were prepared on quartz substrates by rapid thermal chemical vapor deposition(RTCVD) system,and their structures were studied by XRD,SEM and TEM,respectively.XRD spectra exh...Polycrystalline silicon(poly-Si) thin films were prepared on quartz substrates by rapid thermal chemical vapor deposition(RTCVD) system,and their structures were studied by XRD,SEM and TEM,respectively.XRD spectra exhibit a single strong(220) diffraction peak,which indicates that the poly-Si films are preferentially <110> oriented.Plane-view SEM images show that the surface of the poly-Si films is composed of large numbers of polygonal pyramid grains with different sizes,and cross-section SEM images further indicate that they are columnar grains with growth direction perpendicular to substrate surface.TEM observation results demonstrate that there are a lot of twin crystals including one-order,two-order and high-order(≥3) twin crystals in the poly-Si films.The above experimental results can not be elucidated by the conventional opinion on growth behavior of poly-Si films prepared by atmosphere pressure chemical vapor deposition(APCVD),but can be explained by the Ino's multiply twinned particles(MTPs) model found in the face centered cubic metal films.According to the above experimental results and Ino's model,we tend to think that nucleation and grain growth of poly-Si films deposited by RTCVD on quartz substrates are based on the formation of MTPs,and then these MTPs form the continuous films in an island growth mode.展开更多
文摘通过热丝化学气相沉积法(Hot Wire Chemical Vapor Deposition,HWCVD),采用间歇供应硅烷气体,持续通入氢气的方式控制硅薄膜的生长,发现该方法在有机衬底上生长的薄膜结构为多晶相占主导地位。此外,研究了不同间歇周期条件下薄膜的形貌和结构,并对生长机理进行了解释和讨论。
基金Project supported by the National Natural Science Foundation of China(Nos.50802118,60906005)the Natural Science Foundation of Guangdong Province,China(No.9451027501002848)
文摘Selected area laser-crystallized polycrystalline silicon （p-Si） thin films were prepared by the third harmonics （355 nm wavelength） generated by a solid-state pulsed Nd：YAG laser. Surface morphologies of 400 nm thick films after laser irradiation were analyzed. Raman spectra show that film crystallinity is improved with in- crease of laser energy. The optimum laser energy density is sensitive to the film thickness. The laser energy density for efficiently crystallizing amorphous silicon films is between 440-634 mJ/cm^2 for 300 nm thick films and between 777-993 mJ/cm^2 for 400 nm thick films. The optimized laser energy density is 634, 975 and 1571 mJ/cm^2 for 300, 400 and 500 nm thick films, respectively.
基金The national high technology research and development program of China(863 project)(2011AA050507)the national natural science foundation of China(61006050,61076051)+1 种基金the natural science foundation of Beijing(2151004)the fundamental research funds for central universities(13ZD05)
基金supported by the National Natural Science Foundation of China (50802118)National High-Tech Research and Developmen Program of China (2006AA05Z409)+1 种基金China Postdoctor Foundation (20060390741)Natural Science Foundation of Guangdong province (5300577)
文摘Polycrystalline silicon(poly-Si) thin films were prepared on quartz substrates by rapid thermal chemical vapor deposition(RTCVD) system,and their structures were studied by XRD,SEM and TEM,respectively.XRD spectra exhibit a single strong(220) diffraction peak,which indicates that the poly-Si films are preferentially <110> oriented.Plane-view SEM images show that the surface of the poly-Si films is composed of large numbers of polygonal pyramid grains with different sizes,and cross-section SEM images further indicate that they are columnar grains with growth direction perpendicular to substrate surface.TEM observation results demonstrate that there are a lot of twin crystals including one-order,two-order and high-order(≥3) twin crystals in the poly-Si films.The above experimental results can not be elucidated by the conventional opinion on growth behavior of poly-Si films prepared by atmosphere pressure chemical vapor deposition(APCVD),but can be explained by the Ino's multiply twinned particles(MTPs) model found in the face centered cubic metal films.According to the above experimental results and Ino's model,we tend to think that nucleation and grain growth of poly-Si films deposited by RTCVD on quartz substrates are based on the formation of MTPs,and then these MTPs form the continuous films in an island growth mode.
