The effects of multiple scattering on the electron transport properties in drain regions are numerically investigated for the cases of strained-Si diodes with or without scattering in the channel. The performance of n...The effects of multiple scattering on the electron transport properties in drain regions are numerically investigated for the cases of strained-Si diodes with or without scattering in the channel. The performance of non- ballistic (with scattering) channel Si-diodes is compared with that of ballistic (without scattering) channel Si-diodes, using the strain and scattering model. Our results show that the values of the electron velocity and the current in the strain model are higher than the respective values in the unstrained model, and the values of the velocity and the current in the ballistic channel model are higher than the respective values in the non-ballistic channel model. In the strain and scattering models, the effect of each carrier scattering mechanism on the performance of the Si- diodes is analyzed in the drain region. For the ballistic channel model, our results show that inter-valley optical phonon scattering improves device performance, whereas intra-valley acoustic phonon scattering degrades device performance. For the strain model, our results imply that the larger energy splitting of the strained Si could suppress the inter-valley phonon scattering rate. In conclusion, for the drain region, investigation of the strained-Si and scattering mechanisms are necessary, in order to improve the performance of nanoscale ballistic regime devices.展开更多
在模拟计算以 a- Si TFT为有源开关 ,以 a- Si PIN为光敏源的有源成像器件工作特性与各单元元件关系的基础上 ,详细讨论了单元器件的材料、物理参数对 a- Si TFT/PIN耦合对特性的影响 ,并给出一定试验结果 .用 L ED光源照射 a- Si PIN...在模拟计算以 a- Si TFT为有源开关 ,以 a- Si PIN为光敏源的有源成像器件工作特性与各单元元件关系的基础上 ,详细讨论了单元器件的材料、物理参数对 a- Si TFT/PIN耦合对特性的影响 ,并给出一定试验结果 .用 L ED光源照射 a- Si PIN的光电转换率可达 18.1n A/lx,a- Si展开更多
Using p~+-type crystalline Si with n~+-type nanocrystalline Si(nc-Si) and n~+-type crystalline Si with p~+-type nc-Si mosaic structures as electrodes,a type of power diode was prepared with epitaxial technique a...Using p~+-type crystalline Si with n~+-type nanocrystalline Si(nc-Si) and n~+-type crystalline Si with p~+-type nc-Si mosaic structures as electrodes,a type of power diode was prepared with epitaxial technique and plasmaenhanced chemical vapor deposition(PECVD) method.Firstly,the basic p~+-n^--n~+-type Si diode was fabricated by epitaxially growing p~+- and n~+-type layers on two sides of a lightly doped n^--type Si wafer respectively.Secondly,heavily phosphorus-doped Si film was deposited with PECVD on the lithography mask etched p~+-type Si side of the basic device to form a component with mosaic anode.Thirdly,heavily boron-doped Si film was deposited on the etched n~+-type Si side of the second device to form a diode with mosaic anode and mosaic cathode.The images of high resolution transmission electronic microscope and patterns of X-ray diffraction reveal nanocrystallization in the phosphorus- and boron-deposited films.Electrical measurements such as capacitancevoltage relation,current-voltage feature and reverse recovery waveform were carried out to clarify the performance of prepared devices.The important roles of(n^-)Si/(p~+)nc-Si and(n^-)Si/(n~+)nc-Si junctions in the static and dynamic conduction processes in operating diodes were investigated.The performance of mosaic devices was compared to that of a basic one.展开更多
A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting t...A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting the tunable circuit, the matched bandwidth is achieved as wide as possible. Experi- mental results show that the pulse response time of the detector is less than 150 ps within random carrier signal 500 MHz bandwidth range between 35 GHz to 39 GHz via tuning circuit. The detector is very easy to operate because it does not need bias current or synch-pulse source.展开更多
基金supported by the National Natural Science Foundation of China(No.61366001)the National Basic Research Program of China(No.2011CB706601)
文摘The effects of multiple scattering on the electron transport properties in drain regions are numerically investigated for the cases of strained-Si diodes with or without scattering in the channel. The performance of non- ballistic (with scattering) channel Si-diodes is compared with that of ballistic (without scattering) channel Si-diodes, using the strain and scattering model. Our results show that the values of the electron velocity and the current in the strain model are higher than the respective values in the unstrained model, and the values of the velocity and the current in the ballistic channel model are higher than the respective values in the non-ballistic channel model. In the strain and scattering models, the effect of each carrier scattering mechanism on the performance of the Si- diodes is analyzed in the drain region. For the ballistic channel model, our results show that inter-valley optical phonon scattering improves device performance, whereas intra-valley acoustic phonon scattering degrades device performance. For the strain model, our results imply that the larger energy splitting of the strained Si could suppress the inter-valley phonon scattering rate. In conclusion, for the drain region, investigation of the strained-Si and scattering mechanisms are necessary, in order to improve the performance of nanoscale ballistic regime devices.
文摘在模拟计算以 a- Si TFT为有源开关 ,以 a- Si PIN为光敏源的有源成像器件工作特性与各单元元件关系的基础上 ,详细讨论了单元器件的材料、物理参数对 a- Si TFT/PIN耦合对特性的影响 ,并给出一定试验结果 .用 L ED光源照射 a- Si PIN的光电转换率可达 18.1n A/lx,a- Si
基金supported by the National Natural Science Foundation of China(No.61274006)
文摘Using p~+-type crystalline Si with n~+-type nanocrystalline Si(nc-Si) and n~+-type crystalline Si with p~+-type nc-Si mosaic structures as electrodes,a type of power diode was prepared with epitaxial technique and plasmaenhanced chemical vapor deposition(PECVD) method.Firstly,the basic p~+-n^--n~+-type Si diode was fabricated by epitaxially growing p~+- and n~+-type layers on two sides of a lightly doped n^--type Si wafer respectively.Secondly,heavily phosphorus-doped Si film was deposited with PECVD on the lithography mask etched p~+-type Si side of the basic device to form a component with mosaic anode.Thirdly,heavily boron-doped Si film was deposited on the etched n~+-type Si side of the second device to form a diode with mosaic anode and mosaic cathode.The images of high resolution transmission electronic microscope and patterns of X-ray diffraction reveal nanocrystallization in the phosphorus- and boron-deposited films.Electrical measurements such as capacitancevoltage relation,current-voltage feature and reverse recovery waveform were carried out to clarify the performance of prepared devices.The important roles of(n^-)Si/(p~+)nc-Si and(n^-)Si/(n~+)nc-Si junctions in the static and dynamic conduction processes in operating diodes were investigated.The performance of mosaic devices was compared to that of a basic one.
基金supported by the National Natural Science Foundation of China under Grant No. 60801028the Specialized Research fund for the Doctoral Program of Higher Education of China under Grant No. 20070614034
文摘A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting the tunable circuit, the matched bandwidth is achieved as wide as possible. Experi- mental results show that the pulse response time of the detector is less than 150 ps within random carrier signal 500 MHz bandwidth range between 35 GHz to 39 GHz via tuning circuit. The detector is very easy to operate because it does not need bias current or synch-pulse source.