A study of Cl2/BCl3-based inductively coupled plasma (ICP) was conducted using thick photoresist mask for anisotropic etching of 50μm diameter holes in a GaAs wafer at a relatively high average etching rate for etc...A study of Cl2/BCl3-based inductively coupled plasma (ICP) was conducted using thick photoresist mask for anisotropic etching of 50μm diameter holes in a GaAs wafer at a relatively high average etching rate for etching depths of more than 150μm. Plasma etch characteristics with ICP process pressure and the percentage of BCI3 were studied in greater detail at a constant ICP coil/bias power. The measured peak-to-peak voltage as a function of pressure was used to estimate the minimum energy of the ions bombarding the substrate. The process pressure was found to have a substantial influence on the energy of heavy ions. Various ion species in plasma showed minimum energy variation from 1.85 eV to 7.5 eV in the pressure range of 20 mTorr to 50 mTorr. The effect of pressure and the percentage of BCl3 on the etching rate and surface smoothness of the bottom surface of the etched hole were studied for a fixed total flow rate. The etching rate was found to decrease with the percentage of BCl3, whereas the addition of BCl3 resulted in anisotropic holes with a smooth veil free bottom surface at a pressure of 30 mTorr and 42% BC13. In addition, variation of the etching yield with pressure and etching depth were also investigated.展开更多
The capacity of supercapacitor charge storage depends on the size of the electrode surface area and the active material on the electrodes.To enhance the charge storage capacity with a reduced volume,silicon is used as...The capacity of supercapacitor charge storage depends on the size of the electrode surface area and the active material on the electrodes.To enhance the charge storage capacity with a reduced volume,silicon is used as the electrode material,and three-dimensional electrode structure is prepared to increase the electrode surface area on the footprint area by inductively coupled plasma reactive etching(ICP) techniques.The anodic constant current deposition method is employed to deposit manganese oxide on the electrode surface as the electroactive material.For comparison,samples without slot are prepared with a two-dimensional electrode.Scanning Electron Microscopy(SEM) and Energy Dispersive Spectroscopy(EDS) are used to characterize the surface morphology of the electrode structure and the deposited electroactive material.Electrochemical properties of the electrode are characterized by the cyclic voltammetry(CV) and the constant current charge-discharge method.Experimental results show that our approach can effectively increase the electrode surface area with more electroactive substances,and hence can increase storage capacity of the micro-supercapacitor.展开更多
鉴于SiC材料具有很强的稳定性以及湿法刻蚀的种种缺点,目前主要使用干法刻蚀来刻蚀SiC材料。但是干法刻蚀后样品表面的粗糙度对器件的性能有一定的影响。针对这一问题,采用电感耦合等离子体-反应离子刻蚀技术,对SiC材料进行SF_6/O_2混...鉴于SiC材料具有很强的稳定性以及湿法刻蚀的种种缺点,目前主要使用干法刻蚀来刻蚀SiC材料。但是干法刻蚀后样品表面的粗糙度对器件的性能有一定的影响。针对这一问题,采用电感耦合等离子体-反应离子刻蚀技术,对SiC材料进行SF_6/O_2混合气体和SF_6/CF4/O_2混合气体的刻蚀,并且探究了压强、ICP功率和混合气体比例对样品表面粗糙度的影响。实验结果表明使用SF_6/O_2混合气体刻蚀后,样品的表面平整度较好。在一定RIE功率条件下,当ICP功率为700 W、压强为20 m T和SF_6/O_2为50/40 sccm时,样品表面的粗糙度最小。展开更多
文摘A study of Cl2/BCl3-based inductively coupled plasma (ICP) was conducted using thick photoresist mask for anisotropic etching of 50μm diameter holes in a GaAs wafer at a relatively high average etching rate for etching depths of more than 150μm. Plasma etch characteristics with ICP process pressure and the percentage of BCI3 were studied in greater detail at a constant ICP coil/bias power. The measured peak-to-peak voltage as a function of pressure was used to estimate the minimum energy of the ions bombarding the substrate. The process pressure was found to have a substantial influence on the energy of heavy ions. Various ion species in plasma showed minimum energy variation from 1.85 eV to 7.5 eV in the pressure range of 20 mTorr to 50 mTorr. The effect of pressure and the percentage of BCl3 on the etching rate and surface smoothness of the bottom surface of the etched hole were studied for a fixed total flow rate. The etching rate was found to decrease with the percentage of BCl3, whereas the addition of BCl3 resulted in anisotropic holes with a smooth veil free bottom surface at a pressure of 30 mTorr and 42% BC13. In addition, variation of the etching yield with pressure and etching depth were also investigated.
文摘The capacity of supercapacitor charge storage depends on the size of the electrode surface area and the active material on the electrodes.To enhance the charge storage capacity with a reduced volume,silicon is used as the electrode material,and three-dimensional electrode structure is prepared to increase the electrode surface area on the footprint area by inductively coupled plasma reactive etching(ICP) techniques.The anodic constant current deposition method is employed to deposit manganese oxide on the electrode surface as the electroactive material.For comparison,samples without slot are prepared with a two-dimensional electrode.Scanning Electron Microscopy(SEM) and Energy Dispersive Spectroscopy(EDS) are used to characterize the surface morphology of the electrode structure and the deposited electroactive material.Electrochemical properties of the electrode are characterized by the cyclic voltammetry(CV) and the constant current charge-discharge method.Experimental results show that our approach can effectively increase the electrode surface area with more electroactive substances,and hence can increase storage capacity of the micro-supercapacitor.
文摘鉴于SiC材料具有很强的稳定性以及湿法刻蚀的种种缺点,目前主要使用干法刻蚀来刻蚀SiC材料。但是干法刻蚀后样品表面的粗糙度对器件的性能有一定的影响。针对这一问题,采用电感耦合等离子体-反应离子刻蚀技术,对SiC材料进行SF_6/O_2混合气体和SF_6/CF4/O_2混合气体的刻蚀,并且探究了压强、ICP功率和混合气体比例对样品表面粗糙度的影响。实验结果表明使用SF_6/O_2混合气体刻蚀后,样品的表面平整度较好。在一定RIE功率条件下,当ICP功率为700 W、压强为20 m T和SF_6/O_2为50/40 sccm时,样品表面的粗糙度最小。