The N2-plasma treatment on a HfO2 blocking layer of Au nanocrystal nonvolatile memory without any post annealing is investigated. The electrical characteristics of the MOS capacitor with structure of Al–Ta N/HfO2/Si ...The N2-plasma treatment on a HfO2 blocking layer of Au nanocrystal nonvolatile memory without any post annealing is investigated. The electrical characteristics of the MOS capacitor with structure of Al–Ta N/HfO2/Si O2/p-Si are also characterized. After N2-plasma treatment, the nitrogen atoms are incorporated into HfO2 film and may passivate the oxygen vacancy states. The surface roughness of HfO2 film can also be reduced. Those improvements of HfO2 film lead to a smaller hysteresis and lower leakage current density of the MOS capacitor. The N2-plasma is introduced into Au nanocrystal（NC） nonvolatile memory to treat the HfO2 blocking layer. For the N2-plasma treated device, it shows a better retention characteristic and is twice as large in the memory window than that for the no N2-plasma treated device. It can be concluded that the N2-plasma treatment method can be applied to future nonvolatile memory applications.展开更多
This paper discusses the effect of N2 plasma treatment before dielectric deposition on the electrical performance of a Al203/AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor （MISHEMT）,with A...This paper discusses the effect of N2 plasma treatment before dielectric deposition on the electrical performance of a Al203/AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor （MISHEMT）,with Al203 deposited by atomic layer deposition.The results indicated that the gate leakage was decreased two orders of magnitude after the Al203/AlGaN interface was pretreated by N2 plasma.Furthermore,effects of N2 plasma pretreatrnent on the electrical properties of the AlGaN/Al2O3 interface were investigated by x-ray photoelectron spectroscopy measurements and the interface quality between Al203 and AlGaN film was improved.展开更多
In this paper, oxidation of Ge surface by N2O plasma is presented and experimentally demonstrated. Results show that 1.0-nm GeO2 is achieved after 120-s N20 plasma oxidation at 300 ℃. The GeO2/Ge interface is atomica...In this paper, oxidation of Ge surface by N2O plasma is presented and experimentally demonstrated. Results show that 1.0-nm GeO2 is achieved after 120-s N20 plasma oxidation at 300 ℃. The GeO2/Ge interface is atomically smooth. The interface state density of Ge surface after N20 plasma passivation is about - 3 × 1011 cm-2.eV-1. With GeO2 passivation, the hysteresis of metal-oxide-semiconductor （MOS） capacitor with A1203 serving as gate dielectric is reduced to - 50 mV, compared with - 130 mV of the untreated one. The Fermi-level at GeO2/Ge interface is unpinned, and the surface potential is effectively modulated by the gate voltage.展开更多
The influence of an N2O plasma pre-treatment technique on characteristics of AlGaN/GaN high electron mobility transistor（HEMT） prepared by using a plasma-enhanced chemical vapor deposition（PECVD） system is present...The influence of an N2O plasma pre-treatment technique on characteristics of AlGaN/GaN high electron mobility transistor（HEMT） prepared by using a plasma-enhanced chemical vapor deposition（PECVD） system is presented.After the plasma treatment,the peak transconductance（gm） increases from 209 mS/mm to 293 mS/mm.Moreover,it is observed that the reverse gate leakage current is lowered by one order of magnitude and the drain current dispersion is improved in the plasma-treated device.From the analysis of frequency-dependent conductance,it can be seen that the trap state density（DT） and time constant（τT） of the N20-treated device are smaller than those of a non-treated device.The results indicate that the N2O plasma pre-pretreatment before the gate metal deposition could be a promising approach to enhancing the performance of the device.展开更多
为提升瓦斯抽采利用率、促进煤矿安全生产,采用介质阻挡放电(DBD)试验系统对CH4-O2-N2-H2O反应体系进行低温等离子体转化研究,分析水蒸气与CH4物质的量比、O2/N2物质的量比、放电电压、放电频率,以及气体总流量对CH4转化率及主要产物产...为提升瓦斯抽采利用率、促进煤矿安全生产,采用介质阻挡放电(DBD)试验系统对CH4-O2-N2-H2O反应体系进行低温等离子体转化研究,分析水蒸气与CH4物质的量比、O2/N2物质的量比、放电电压、放电频率,以及气体总流量对CH4转化率及主要产物产率的影响。结果表明:CH4-O2-N2-H2O反应体系DBD的主要产物为H2、CO、CO2、C2H2、C2H4、C2H6和CH3OH;反应参数对CH4转化率和H2、CO、CO2、C2H6、CH3OH产率影响较为显著,而对C2H2、C2H4产率影响不显著;CH4转化率及主要产物产率均在放电频率为9.8 k Hz时取得最大值。展开更多
Planar radio frequency inductively coupled plasmas（ICP） are employed for low-voltage ion implantation processes,with capacitive pulse biasing of the substrate for modulation of the ion energy. In this work, a two-di...Planar radio frequency inductively coupled plasmas（ICP） are employed for low-voltage ion implantation processes,with capacitive pulse biasing of the substrate for modulation of the ion energy. In this work, a two-dimensional（2D） selfconsistent fluid model has been employed to investigate the influence of the pulsed bias power on the nitrogen plasmas for various bias voltages and pulse frequencies. The results indicate that the plasma density as well as the inductive power density increase significantly when the bias voltage varies from 0 V to-4000 V, due to the heating of the capacitive field caused by the bias power. The N＋fraction increases rapidly to a maximum at the beginning of the power-on time, and then it decreases and reaches the steady state at the end of the glow period. Moreover, it increases with the bias voltage during the power-on time, whereas the N2-＋ fraction exhibits a reverse behavior. When the pulse frequency increases to 25 kHz and40 kHz, the plasma steady state cannot be obtained, and a rapid decrease of the ion density at the substrate surface at the beginning of the glow period is observed.展开更多
A two-dimensional （2D） fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma （CCP） reactor. The plasma–wall interaction ...A two-dimensional （2D） fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma （CCP） reactor. The plasma–wall interaction （including the deposition） is modeled by using surface reaction coefficients. In the present paper we try to identify, by numerical simulations, the effect of variations of the process parameters on the plasma properties. It is found from our simulations that by increasing the gas pressure and the discharge gap, the electron density profile shape changes continuously from an edge-high to a center-high, thus the thin films become more uniform. Moreover, as the N2 /NH3 ratio increases from 6/13 to 10/9, the hydrogen content can be significantly decreased, without decreasing the electron density significantly.展开更多
It is known that gas flow rate is a key factor in controlling industrial plasma processing. In this paper, a 2D PIC/MCC model is developed for an rf hollow cathode discharge with an axial nitrogen gas flow. The effect...It is known that gas flow rate is a key factor in controlling industrial plasma processing. In this paper, a 2D PIC/MCC model is developed for an rf hollow cathode discharge with an axial nitrogen gas flow. The effects of the gas flow rate on the plasma parameters are calculated and the results show that： with an increasing flow rate, the total ion（N＋2, N＋） density decreases, the mean sheath thickness becomes wider, the radial electric field in the sheath and the axial electric field show an increase, and the energies of both kinds of nitrogen ions increase;and, as the axial ion current density that is moving toward the ground electrode increases, the ion current density near the ground electrode increases. The simulation results will provide a useful reference for plasma jet technology involving rf hollow cathode discharges in N2.展开更多
基金supported by the High Level Talent Project of Xiamen University of Technology,China(Grant Nos.YKJ16012R and YKJ16016R)the National Natural Science Foundation of China(Grant No.51702271)
文摘The N2-plasma treatment on a HfO2 blocking layer of Au nanocrystal nonvolatile memory without any post annealing is investigated. The electrical characteristics of the MOS capacitor with structure of Al–Ta N/HfO2/Si O2/p-Si are also characterized. After N2-plasma treatment, the nitrogen atoms are incorporated into HfO2 film and may passivate the oxygen vacancy states. The surface roughness of HfO2 film can also be reduced. Those improvements of HfO2 film lead to a smaller hysteresis and lower leakage current density of the MOS capacitor. The N2-plasma is introduced into Au nanocrystal（NC） nonvolatile memory to treat the HfO2 blocking layer. For the N2-plasma treated device, it shows a better retention characteristic and is twice as large in the memory window than that for the no N2-plasma treated device. It can be concluded that the N2-plasma treatment method can be applied to future nonvolatile memory applications.
基金Project supported by National Advanced Research Program (Grant No 51308030102)Xi’an Applied Materials Innovation Fund (Grant No XA-AM-200616)National Natural Science Foundation of China (Grant Nos 60506020 and 60676048)
文摘This paper discusses the effect of N2 plasma treatment before dielectric deposition on the electrical performance of a Al203/AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor （MISHEMT）,with Al203 deposited by atomic layer deposition.The results indicated that the gate leakage was decreased two orders of magnitude after the Al203/AlGaN interface was pretreated by N2 plasma.Furthermore,effects of N2 plasma pretreatrnent on the electrical properties of the AlGaN/Al2O3 interface were investigated by x-ray photoelectron spectroscopy measurements and the interface quality between Al203 and AlGaN film was improved.
基金supported by the National Basic Research Program of China(Grant No.2011CBA00601)the National Natural Science Foundation of China(Grant Nos.60625403,60806033,and 60925015)
文摘In this paper, oxidation of Ge surface by N2O plasma is presented and experimentally demonstrated. Results show that 1.0-nm GeO2 is achieved after 120-s N20 plasma oxidation at 300 ℃. The GeO2/Ge interface is atomically smooth. The interface state density of Ge surface after N20 plasma passivation is about - 3 × 1011 cm-2.eV-1. With GeO2 passivation, the hysteresis of metal-oxide-semiconductor （MOS） capacitor with A1203 serving as gate dielectric is reduced to - 50 mV, compared with - 130 mV of the untreated one. The Fermi-level at GeO2/Ge interface is unpinned, and the surface potential is effectively modulated by the gate voltage.
基金supported by the National Natural Science Foundation of China(Grant No.61334002)the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory,China(Grant No.ZHD201206)
文摘The influence of an N2O plasma pre-treatment technique on characteristics of AlGaN/GaN high electron mobility transistor（HEMT） prepared by using a plasma-enhanced chemical vapor deposition（PECVD） system is presented.After the plasma treatment,the peak transconductance（gm） increases from 209 mS/mm to 293 mS/mm.Moreover,it is observed that the reverse gate leakage current is lowered by one order of magnitude and the drain current dispersion is improved in the plasma-treated device.From the analysis of frequency-dependent conductance,it can be seen that the trap state density（DT） and time constant（τT） of the N20-treated device are smaller than those of a non-treated device.The results indicate that the N2O plasma pre-pretreatment before the gate metal deposition could be a promising approach to enhancing the performance of the device.
文摘为提升瓦斯抽采利用率、促进煤矿安全生产,采用介质阻挡放电(DBD)试验系统对CH4-O2-N2-H2O反应体系进行低温等离子体转化研究,分析水蒸气与CH4物质的量比、O2/N2物质的量比、放电电压、放电频率,以及气体总流量对CH4转化率及主要产物产率的影响。结果表明:CH4-O2-N2-H2O反应体系DBD的主要产物为H2、CO、CO2、C2H2、C2H4、C2H6和CH3OH;反应参数对CH4转化率和H2、CO、CO2、C2H6、CH3OH产率影响较为显著,而对C2H2、C2H4产率影响不显著;CH4转化率及主要产物产率均在放电频率为9.8 k Hz时取得最大值。
基金supported by the National Natural Science Foundation of China(Grant Nos.11175034,11335004,and 11405019)the Important National Science and Technology Specific Project of China(Grant No.2011 ZX 02403-001)
文摘Planar radio frequency inductively coupled plasmas（ICP） are employed for low-voltage ion implantation processes,with capacitive pulse biasing of the substrate for modulation of the ion energy. In this work, a two-dimensional（2D） selfconsistent fluid model has been employed to investigate the influence of the pulsed bias power on the nitrogen plasmas for various bias voltages and pulse frequencies. The results indicate that the plasma density as well as the inductive power density increase significantly when the bias voltage varies from 0 V to-4000 V, due to the heating of the capacitive field caused by the bias power. The N＋fraction increases rapidly to a maximum at the beginning of the power-on time, and then it decreases and reaches the steady state at the end of the glow period. Moreover, it increases with the bias voltage during the power-on time, whereas the N2-＋ fraction exhibits a reverse behavior. When the pulse frequency increases to 25 kHz and40 kHz, the plasma steady state cannot be obtained, and a rapid decrease of the ion density at the substrate surface at the beginning of the glow period is observed.
基金Project supported by the China Postdoctoral Science Foundation (Grant No. 2012M511603)the National Natural Science Foundation of China (Grant Nos. 11105057 and 10775025)+1 种基金the Natural Science Foundation of Hubei Province of China (Grant No. 2007ABA035)the Program for New Century Excellent Talents in University of China (Grant No. NCET-08-0073)
文摘A two-dimensional （2D） fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma （CCP） reactor. The plasma–wall interaction （including the deposition） is modeled by using surface reaction coefficients. In the present paper we try to identify, by numerical simulations, the effect of variations of the process parameters on the plasma properties. It is found from our simulations that by increasing the gas pressure and the discharge gap, the electron density profile shape changes continuously from an edge-high to a center-high, thus the thin films become more uniform. Moreover, as the N2 /NH3 ratio increases from 6/13 to 10/9, the hydrogen content can be significantly decreased, without decreasing the electron density significantly.
基金supported by the Natural Science Foundation of Hebei Province,China(No.A2012205072)
文摘It is known that gas flow rate is a key factor in controlling industrial plasma processing. In this paper, a 2D PIC/MCC model is developed for an rf hollow cathode discharge with an axial nitrogen gas flow. The effects of the gas flow rate on the plasma parameters are calculated and the results show that： with an increasing flow rate, the total ion（N＋2, N＋） density decreases, the mean sheath thickness becomes wider, the radial electric field in the sheath and the axial electric field show an increase, and the energies of both kinds of nitrogen ions increase;and, as the axial ion current density that is moving toward the ground electrode increases, the ion current density near the ground electrode increases. The simulation results will provide a useful reference for plasma jet technology involving rf hollow cathode discharges in N2.
