Electron cyclotron resonance radio frequency (ECR-rf) hybrid krypton-diluted oxygen plasmas were used to pattern the surfaces of diamond films with the assistance of a physical mask, while optical emission spectrosc...Electron cyclotron resonance radio frequency (ECR-rf) hybrid krypton-diluted oxygen plasmas were used to pattern the surfaces of diamond films with the assistance of a physical mask, while optical emission spectroscopy was employed to characterize the plasma. It was found that with krypton dilution the etching rate decreased, and also the aspect ratios of nanotips formed in micro-holes were significantly modified. The oxygen atomic densities were estimated by oxygen atom optical emission and argon actinometry. Under a microwave power of 300 W and rf bias of-300 V, the absolute density of ground-state oxygen atoms decreased from 1.3×10^12 cm^-3 to 1.4×10^11 cm^-3 as the krypton dilution ratio increased to 80%, accompanied by the decrease in the plasma excitation temperature. It is concluded that oxygen atoms play a dominant role in diamond etching. The relative variations in the horizontal and vertical etching rates induced by the addition of krypton are attributed to the observations of thicker nanotips at a high krypton dilution ratio.展开更多
Chemically vapor deposited diamond films were etched at different parameters using oxygen plasma produced by a DC (direct current) glow discharge and then polished by a modified mechanical polishing device. Scanning...Chemically vapor deposited diamond films were etched at different parameters using oxygen plasma produced by a DC (direct current) glow discharge and then polished by a modified mechanical polishing device. Scanning electron microscope, atomic force microscope and Raman spectrometer were used to evaluate the surface states of diamond films before and after polishing. It was found that a moderate plasma etching would produce a lot of etch pits and amorphous carbon on the top surface of diamond film. As a result, the quality and the efficiency of mechanical polishing have been enhanced remarkably.展开更多
Tremendous demands for highly sensitive and stable seawater salinometers have motivated intensive research on advanced electrode materials.Boron-doped diamond(BDD)is attractive in terms of its high mechanical stabilit...Tremendous demands for highly sensitive and stable seawater salinometers have motivated intensive research on advanced electrode materials.Boron-doped diamond(BDD)is attractive in terms of its high mechanical stability and chemical inertness,but is usually hindered by its low double-layer capacitance(C_(dl))for seawater salinity detection.Here,inspired by the principle of oxygen-terminated BDD electrode endowing higher C_(dl)than hydrogen-terminated surface,we introduce the oxygen terminated surface by oxygen plasma or reactive ion etch(RIE),and the fabricated oxygen terminated BDD electrodes demonstrate high sensitivity and long-term stability in seawater salinity detection comparing with the hydrogen terminated BDD electrodes.Significantly,the as-fabricated O-BDD-RIE electrodes not only show remarkable enhanced response even better than the commercial platinum black electrodes but also display long-time stability which is weekly verified by continuous monitor for 90 days.The outstanding performance of the oxygen terminated BDD electrodes can be ascribed to the enhancement of C-O surface functional group on C_(dl).In addition,a comprehensive analysis of effective electroactive surface area(EASA)and C_(dl)proves that the surface oxygen is the major factor for the improved C_(dl).In summary,the excellent oxygen terminated BDD electrodes promise potential application in seawater salinity detection.展开更多
Atmospheric-pressure(AP)plasma etching provides an alternative method for mechanical grinding to realize wafer thinning of Si wafer.It can avoid the damages and micro-cracks that would be introduced by mechanical stre...Atmospheric-pressure(AP)plasma etching provides an alternative method for mechanical grinding to realize wafer thinning of Si wafer.It can avoid the damages and micro-cracks that would be introduced by mechanical stress during the grinding process.In this study,the material removal characteristics of Si(100)wafer processed by linear field AP plasma generated using carbon tetrafluoride(CF4)as the reactive source were analyzed.This linear field plasma etching tool has a typical removal profile and the depth removal rate that can reach up to 1.082μm/min.The effect ofO2 concentration on the removal ratewas discussed and the surfacemorphology during the process was characterized using scanning electron microscopy.It is shown that the subsurface damage layer was gradually removed during the etching process and the surface was observed to be smoothened with the increase of the etching depth.This present work contributes a basic understanding of the linear field AP plasma etching performance with different gas composition and the typical characteristics would be further applied to damage-free precision removal of Si.展开更多
基金supported by National Natural Science Foundation of China (No. 10635010)National Basic Research Program of China (No. 2008CB717800)
文摘Electron cyclotron resonance radio frequency (ECR-rf) hybrid krypton-diluted oxygen plasmas were used to pattern the surfaces of diamond films with the assistance of a physical mask, while optical emission spectroscopy was employed to characterize the plasma. It was found that with krypton dilution the etching rate decreased, and also the aspect ratios of nanotips formed in micro-holes were significantly modified. The oxygen atomic densities were estimated by oxygen atom optical emission and argon actinometry. Under a microwave power of 300 W and rf bias of-300 V, the absolute density of ground-state oxygen atoms decreased from 1.3×10^12 cm^-3 to 1.4×10^11 cm^-3 as the krypton dilution ratio increased to 80%, accompanied by the decrease in the plasma excitation temperature. It is concluded that oxygen atoms play a dominant role in diamond etching. The relative variations in the horizontal and vertical etching rates induced by the addition of krypton are attributed to the observations of thicker nanotips at a high krypton dilution ratio.
基金National Natural Science Foundation of China(No.50572075)
文摘Chemically vapor deposited diamond films were etched at different parameters using oxygen plasma produced by a DC (direct current) glow discharge and then polished by a modified mechanical polishing device. Scanning electron microscope, atomic force microscope and Raman spectrometer were used to evaluate the surface states of diamond films before and after polishing. It was found that a moderate plasma etching would produce a lot of etch pits and amorphous carbon on the top surface of diamond film. As a result, the quality and the efficiency of mechanical polishing have been enhanced remarkably.
基金financially supported by the Joint Research Fund Liaoning-Shenyang National Laboratory for Materials Science(No.20180510009)the Young Talent Program of Shenyang National Laboratory for Materials Science(No.L2019F39)the National Natural Science Foundation of China(No.51202257)。
文摘Tremendous demands for highly sensitive and stable seawater salinometers have motivated intensive research on advanced electrode materials.Boron-doped diamond(BDD)is attractive in terms of its high mechanical stability and chemical inertness,but is usually hindered by its low double-layer capacitance(C_(dl))for seawater salinity detection.Here,inspired by the principle of oxygen-terminated BDD electrode endowing higher C_(dl)than hydrogen-terminated surface,we introduce the oxygen terminated surface by oxygen plasma or reactive ion etch(RIE),and the fabricated oxygen terminated BDD electrodes demonstrate high sensitivity and long-term stability in seawater salinity detection comparing with the hydrogen terminated BDD electrodes.Significantly,the as-fabricated O-BDD-RIE electrodes not only show remarkable enhanced response even better than the commercial platinum black electrodes but also display long-time stability which is weekly verified by continuous monitor for 90 days.The outstanding performance of the oxygen terminated BDD electrodes can be ascribed to the enhancement of C-O surface functional group on C_(dl).In addition,a comprehensive analysis of effective electroactive surface area(EASA)and C_(dl)proves that the surface oxygen is the major factor for the improved C_(dl).In summary,the excellent oxygen terminated BDD electrodes promise potential application in seawater salinity detection.
文摘Atmospheric-pressure(AP)plasma etching provides an alternative method for mechanical grinding to realize wafer thinning of Si wafer.It can avoid the damages and micro-cracks that would be introduced by mechanical stress during the grinding process.In this study,the material removal characteristics of Si(100)wafer processed by linear field AP plasma generated using carbon tetrafluoride(CF4)as the reactive source were analyzed.This linear field plasma etching tool has a typical removal profile and the depth removal rate that can reach up to 1.082μm/min.The effect ofO2 concentration on the removal ratewas discussed and the surfacemorphology during the process was characterized using scanning electron microscopy.It is shown that the subsurface damage layer was gradually removed during the etching process and the surface was observed to be smoothened with the increase of the etching depth.This present work contributes a basic understanding of the linear field AP plasma etching performance with different gas composition and the typical characteristics would be further applied to damage-free precision removal of Si.