The silicon nano-crystalline (nc-Si) film is fabricated on <100> orientation,0.01Ω·cm resistivity,and p-type boron-doped silicon wafer by the anodic etching.The microstructure and the orientation of nc-Si ...The silicon nano-crystalline (nc-Si) film is fabricated on <100> orientation,0.01Ω·cm resistivity,and p-type boron-doped silicon wafer by the anodic etching.The microstructure and the orientation of nc-Si are examined by the scanning electron microscopy,transmission electron microscopy,and X-ray diffraction spectroscopy,respectively.The average size of particle is estimated by Raman spectroscopy.The results show that the particle size of nc-Si film is scattered from 10nm to 20nm,the alignment is compact,the orientation is uniform,the expansion of lattice constant is negligible,and mechanical robustness and stability are good.The correlations between film structure and the experiment parameters such as etching time,HF concentration,and etching current density are discussed.As a potential application,efficient field emission is observed from the nc-Si film,and the turn-on field is about 3V/μm at 0.1μA/cm 2 of current density,which is close to carbon nanotube film's.展开更多
Intensive blue photoluminescence （PL） was observed at room temperature from the nanocrystalline-Si/SiO2 （nc-Si/SiO2） multilayers （MLs） obtained by thermal annealing of SiO/SiO2 MLs for the first time. By control...Intensive blue photoluminescence （PL） was observed at room temperature from the nanocrystalline-Si/SiO2 （nc-Si/SiO2） multilayers （MLs） obtained by thermal annealing of SiO/SiO2 MLs for the first time. By controlling the size of nc-Si formed in SiO sublayer from 3.5 to 1.5 nm, the PL peak blueshifts from 457 to 411 nm. Combining the analysis of TEM, Raman and absorption measurement, this paper attributes the blue PL to multiple luminescent centres at the interface of nc-Si and SiO2.展开更多
Doubly stacked nanocrystalline-Si (nc-Si) based metal insulator semiconductor memory structure was fabricated by plasma enhanced chemical vapor deposition. Capacitance-Voltage (C-V) and capacitance-time (C-t) measurem...Doubly stacked nanocrystalline-Si (nc-Si) based metal insulator semiconductor memory structure was fabricated by plasma enhanced chemical vapor deposition. Capacitance-Voltage (C-V) and capacitance-time (C-t) measurements were used to investigate electron tunnel, storage and discharging characteristic. The C-V results show that the flatband voltage increases at first, then decreases and finally increases, exhibiting a clear deep at gate voltage of 9 V. The de-creasing of flatband voltage at moderate programming bias is attributed to the transfer of electrons from the lower nc-Si layer to the upper nc-Si layer. The C-t measurement results show that the charges transfer in the structure strongly de-pends on the hold time and the flatband voltage decreases markedly with increasing the hold time.展开更多
The early stages of hydrogenated nanocrystalline silicon （nc-Si：H） films deposited by plasma-enhanced chemical vapour deposition were characterized by atomic force microscopy. To increase the density of nanocrystal...The early stages of hydrogenated nanocrystalline silicon （nc-Si：H） films deposited by plasma-enhanced chemical vapour deposition were characterized by atomic force microscopy. To increase the density of nanocrystals in the nc-Si：H films, the films were annealed by rapid thermal annealing （RTA） at different temperatures and then analysed by Raman spectroscopy. It was found that the recrystallization process of the film was optimal at around 1000℃. The effects of different RTA conditions on charge storage were characterized by capacitance-voltage measurement. Experimental results show that nc-Si：H films obtained by RTA have good charge storage characteristics for nonvolatile memory.展开更多
利用等离子增强化学气相沉积(PECVD)技术,采用NH_3等离子体预氮化法淀积α-SiN_x介质膜,同时结合layer by layer生长nc-Si的方法一次性原位制备了α-SiN_x/nc-Si/α-SiN_x双势垒结构样品.通过原子力显微镜(AFM)测量,估算了nc-Si的密度为...利用等离子增强化学气相沉积(PECVD)技术,采用NH_3等离子体预氮化法淀积α-SiN_x介质膜,同时结合layer by layer生长nc-Si的方法一次性原位制备了α-SiN_x/nc-Si/α-SiN_x双势垒结构样品.通过原子力显微镜(AFM)测量,估算了nc-Si的密度为1.2×10^(11)cm^(-2).通过C-V测量研究镶嵌在SiN_x双势垒层中的nc-Si颗粒的电荷存储现象.C-V曲线出现明显的迥滞现象,迴滞窗口约为1 V,表明结构中电荷存储特性.根据迴滞窗口,计算了结构中存储电荷的密度,发现存储电荷密度与nc-Si层的晶粒密度具有相同的数量级.展开更多
在PECVD系统中,用layer by layer的方法原位制备了a-SiNx/nc-Si/a-SiNx双势垒结构样品。AFM测量结果显示nc-Si晶粒密度约为1.2×1011cm-2,通过Raman散射谱计算出薄膜中的平均晶粒尺寸为6nm,nc-Si层的晶化比约46%。在低频时的电容-电...在PECVD系统中,用layer by layer的方法原位制备了a-SiNx/nc-Si/a-SiNx双势垒结构样品。AFM测量结果显示nc-Si晶粒密度约为1.2×1011cm-2,通过Raman散射谱计算出薄膜中的平均晶粒尺寸为6nm,nc-Si层的晶化比约46%。在低频时的电容-电压(C-V)测试过程中,观察到了与共振隧穿效应有关的电容峰,由于样品中的nc-Si颗粒尺寸均匀性不高,没有观察到分立的隧穿电容峰结构,只得到扩展的电容峰。展开更多
文摘The silicon nano-crystalline (nc-Si) film is fabricated on <100> orientation,0.01Ω·cm resistivity,and p-type boron-doped silicon wafer by the anodic etching.The microstructure and the orientation of nc-Si are examined by the scanning electron microscopy,transmission electron microscopy,and X-ray diffraction spectroscopy,respectively.The average size of particle is estimated by Raman spectroscopy.The results show that the particle size of nc-Si film is scattered from 10nm to 20nm,the alignment is compact,the orientation is uniform,the expansion of lattice constant is negligible,and mechanical robustness and stability are good.The correlations between film structure and the experiment parameters such as etching time,HF concentration,and etching current density are discussed.As a potential application,efficient field emission is observed from the nc-Si film,and the turn-on field is about 3V/μm at 0.1μA/cm 2 of current density,which is close to carbon nanotube film's.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 60508009, 60471021, 60571008 and 10574069)the Nature Science Foundation of Jiangsu Province, China (Grant No BK2007135)
文摘Intensive blue photoluminescence （PL） was observed at room temperature from the nanocrystalline-Si/SiO2 （nc-Si/SiO2） multilayers （MLs） obtained by thermal annealing of SiO/SiO2 MLs for the first time. By controlling the size of nc-Si formed in SiO sublayer from 3.5 to 1.5 nm, the PL peak blueshifts from 457 to 411 nm. Combining the analysis of TEM, Raman and absorption measurement, this paper attributes the blue PL to multiple luminescent centres at the interface of nc-Si and SiO2.
文摘Doubly stacked nanocrystalline-Si (nc-Si) based metal insulator semiconductor memory structure was fabricated by plasma enhanced chemical vapor deposition. Capacitance-Voltage (C-V) and capacitance-time (C-t) measurements were used to investigate electron tunnel, storage and discharging characteristic. The C-V results show that the flatband voltage increases at first, then decreases and finally increases, exhibiting a clear deep at gate voltage of 9 V. The de-creasing of flatband voltage at moderate programming bias is attributed to the transfer of electrons from the lower nc-Si layer to the upper nc-Si layer. The C-t measurement results show that the charges transfer in the structure strongly de-pends on the hold time and the flatband voltage decreases markedly with increasing the hold time.
基金Project supported by the National Basic Research Program of China （973 Program） （Grant No 2006CB302706） and the National Natural Science Foundation of China （Grant Nos 90607022, 904010027 90207004, and 60506005）.
文摘The early stages of hydrogenated nanocrystalline silicon （nc-Si：H） films deposited by plasma-enhanced chemical vapour deposition were characterized by atomic force microscopy. To increase the density of nanocrystals in the nc-Si：H films, the films were annealed by rapid thermal annealing （RTA） at different temperatures and then analysed by Raman spectroscopy. It was found that the recrystallization process of the film was optimal at around 1000℃. The effects of different RTA conditions on charge storage were characterized by capacitance-voltage measurement. Experimental results show that nc-Si：H films obtained by RTA have good charge storage characteristics for nonvolatile memory.
文摘利用等离子增强化学气相沉积(PECVD)技术,采用NH_3等离子体预氮化法淀积α-SiN_x介质膜,同时结合layer by layer生长nc-Si的方法一次性原位制备了α-SiN_x/nc-Si/α-SiN_x双势垒结构样品.通过原子力显微镜(AFM)测量,估算了nc-Si的密度为1.2×10^(11)cm^(-2).通过C-V测量研究镶嵌在SiN_x双势垒层中的nc-Si颗粒的电荷存储现象.C-V曲线出现明显的迥滞现象,迴滞窗口约为1 V,表明结构中电荷存储特性.根据迴滞窗口,计算了结构中存储电荷的密度,发现存储电荷密度与nc-Si层的晶粒密度具有相同的数量级.
文摘在PECVD系统中,用layer by layer的方法原位制备了a-SiNx/nc-Si/a-SiNx双势垒结构样品。AFM测量结果显示nc-Si晶粒密度约为1.2×1011cm-2,通过Raman散射谱计算出薄膜中的平均晶粒尺寸为6nm,nc-Si层的晶化比约46%。在低频时的电容-电压(C-V)测试过程中,观察到了与共振隧穿效应有关的电容峰,由于样品中的nc-Si颗粒尺寸均匀性不高,没有观察到分立的隧穿电容峰结构,只得到扩展的电容峰。
