Dry etching of 6H silicon carbide （6H-SiC） wafers in a C4Fs/Ar dual-frequency capacitively coupled plasma （DF-CCP） was investigated. Atomic force microscopy （AFM） and X-ray photoelectron spectroscopy （XPS） wer...Dry etching of 6H silicon carbide （6H-SiC） wafers in a C4Fs/Ar dual-frequency capacitively coupled plasma （DF-CCP） was investigated. Atomic force microscopy （AFM） and X-ray photoelectron spectroscopy （XPS） were used to measure the SiC surface structure and compositions, respectively. Optical emission spectroscopy （OES） was used to measure the relative concentration of F radicals in the plasma. It was found that the roughness of the etched SiC surface and the etching rate are directly related to the power of low-frequency （LF） source. At lower LF power, a smaller surface roughness and a lower etching rate are obtained due to weak bombardment of low energy ions on the SiC wafers. At higher LF power the etching rate can be efficiently increased, but the surface roughness increases too. Compared with other plasma dry etching methods, the DF-CCP can effectively inhibit CχFγ films＇ deposition, and reduce surface residues.展开更多
Dynamic dimension assessments of tumor tissues have broad relevance in clinical diagnosis and treatments of patients.Current technologies for such purpose include quasi-static measurements that lack microscale resolut...Dynamic dimension assessments of tumor tissues have broad relevance in clinical diagnosis and treatments of patients.Current technologies for such purpose include quasi-static measurements that lack microscale resolution and sensing sites,with limited capabilities for time-dependent,three-dimensional profiling of tumors particularly at early growth stage.Here,we report the conformal Hall-sensor-based systems for continuous monitoring of tumor morphological features such as growth rates and volumes.Such platforms incorporate ultrathin crystalline-silicon nanomembranes(200 nm thick)as basis for displacement sensing via magnetic flux detection,in an array design that yields spatiotemporal information of tumor geometries at high sensitivity.Evaluation involves real-time measurements on a living mouse model with tumor tissues at various pathological conditions,where the integration with deep learning algorithms can further enable the system for large-scale tumor profile reconstruction across tissue surfaces.These microsystems provide the potential for monitoring of tumor progression and treatment guidance in patients.展开更多
Patterned flow sensor cell consisting of single-walled carbon nanotubes (SWCNTs) network and polydimethylsiloxane (PDMS) are fabricated,based on the process of vacuum filtration,photolithography,and plasma etching.The...Patterned flow sensor cell consisting of single-walled carbon nanotubes (SWCNTs) network and polydimethylsiloxane (PDMS) are fabricated,based on the process of vacuum filtration,photolithography,and plasma etching.The sensor cell is a composite thin film and packaged to form a flow sensor,and then tested in different flow rates with different liquids,such as deionized (DI) water and NaCl solution.The induced-voltage increases with increasing flowing velocity and liquid concentration.The relation between induced-voltage and sensor cell conductivity is tested in the same liquid at the same flow rate.The higher the conductivity is,the higher the induced-voltage is.Some of the SWCNTs are fixed in the PDMS matrix,simultaneously some of them protrude above the composite thin film,which are exposed to the liquid and contribute to the voltage generation.The fabrication method can make the flow sensor scaled down to dimensions on the order of micrometers,which makes it suitable in very small liquid volumes.展开更多
基金supported by National Natural Science Foundation of China （Nos. 10975105, 11275136, 10975106, 11175126, 11204266 and 11075114） the National Magnetic Confinement Fusion Science Program of China （Nos. 2010GB106000, 2010GB106009）, the Open Project of State Key Laboratory of Functional Materials for Information and Qing Lan Project, a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions and the Program for graduates Research ＆ Innovation in University of Jiangsu Province, China （No. CX10B-031Z）
文摘Dry etching of 6H silicon carbide （6H-SiC） wafers in a C4Fs/Ar dual-frequency capacitively coupled plasma （DF-CCP） was investigated. Atomic force microscopy （AFM） and X-ray photoelectron spectroscopy （XPS） were used to measure the SiC surface structure and compositions, respectively. Optical emission spectroscopy （OES） was used to measure the relative concentration of F radicals in the plasma. It was found that the roughness of the etched SiC surface and the etching rate are directly related to the power of low-frequency （LF） source. At lower LF power, a smaller surface roughness and a lower etching rate are obtained due to weak bombardment of low energy ions on the SiC wafers. At higher LF power the etching rate can be efficiently increased, but the surface roughness increases too. Compared with other plasma dry etching methods, the DF-CCP can effectively inhibit CχFγ films＇ deposition, and reduce surface residues.
基金supported by the STI 2030-Major Project(2022ZD0209900)the National Natural Science Foundation of China(62204057,62304044,82304124,12425204)+9 种基金Science and Technology Commission of Shanghai Municipality(22ZR1406400)State Key Laboratory of Integrated Chips and Systems(SKLICS-Z202306)National Key R&D Program of China(2022YFB3204800)CAS Project for Young Scientists in Basic Research(YSBR-081)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0670000)We also appreciate the support by Shanghai Municipal Science and Technology Major Project(2018SHZDZX01)ZJ Lab,Shanghai Center for Brain Science and Brain-Inspired Technologythe young scientist project of MOE innovation platformthe China Postdoctoral Science Foundation(2023M730712)Part of the experimental work was carried out in Fudan Nanofabrication Laboratory.
文摘Dynamic dimension assessments of tumor tissues have broad relevance in clinical diagnosis and treatments of patients.Current technologies for such purpose include quasi-static measurements that lack microscale resolution and sensing sites,with limited capabilities for time-dependent,three-dimensional profiling of tumors particularly at early growth stage.Here,we report the conformal Hall-sensor-based systems for continuous monitoring of tumor morphological features such as growth rates and volumes.Such platforms incorporate ultrathin crystalline-silicon nanomembranes(200 nm thick)as basis for displacement sensing via magnetic flux detection,in an array design that yields spatiotemporal information of tumor geometries at high sensitivity.Evaluation involves real-time measurements on a living mouse model with tumor tissues at various pathological conditions,where the integration with deep learning algorithms can further enable the system for large-scale tumor profile reconstruction across tissue surfaces.These microsystems provide the potential for monitoring of tumor progression and treatment guidance in patients.
基金the National High-Tech Research & Development Program of China (2007AA04Z348)China Postdoctoral Science Foundation (20080440139)
文摘Patterned flow sensor cell consisting of single-walled carbon nanotubes (SWCNTs) network and polydimethylsiloxane (PDMS) are fabricated,based on the process of vacuum filtration,photolithography,and plasma etching.The sensor cell is a composite thin film and packaged to form a flow sensor,and then tested in different flow rates with different liquids,such as deionized (DI) water and NaCl solution.The induced-voltage increases with increasing flowing velocity and liquid concentration.The relation between induced-voltage and sensor cell conductivity is tested in the same liquid at the same flow rate.The higher the conductivity is,the higher the induced-voltage is.Some of the SWCNTs are fixed in the PDMS matrix,simultaneously some of them protrude above the composite thin film,which are exposed to the liquid and contribute to the voltage generation.The fabrication method can make the flow sensor scaled down to dimensions on the order of micrometers,which makes it suitable in very small liquid volumes.
