共查询到20条相似文献,搜索用时 609 毫秒
1.
Plasma and electrical characteristics of an internal-type inductively coupled plasma source with a Ni–Zn ferrite module installed
near the antenna were investigated for different rf power frequencies of 2 and 13.56 MHz. Due to the lower heating of the
Ni–Zn ferrite module on the antenna for the operation at 2 MHz compared to the operation at 13.56 MHz, higher plasma density
and lower rf rms antenna voltage were resulted for the operation at 2 MHz in addition to more stable plasma characteristics.
By the application of 500 W of rf power to the source, a high plasma density of 8 × 10 11 cm −3 which is about four times higher than that with 13.56 MHz could be obtained at the pressure of 10 mTorr Ar. When photoresist
etch uniformity was measured for the operation with 2 MHz by etching photoresist on a 300 mm diameter substrate using 10 mTorr
Ar/O 2 (9:1) mixture, the etch uniformity of about 5.5% could be obtained. 相似文献
2.
An internal-type linear inductive antenna, which is referred to as “double comb-type antenna”, was used as a large-area inductively
coupled plasma (ICP) source with a substrate area of 2,300 mm × 2,000 mm. The characteristics of the ICP source were investigated
for potential applications to flat panel display (FPD) processing. The source showed higher power transfer efficiency at higher
RF power and higher operating pressures. The power transfer efficiency was approximately 88.1% at 9 kW of RF power and a pressure
of 20 mTorr Ar. This source showed increasing plasma density and improved plasma uniformity with increasing RF power at a
given operating pressure. A plasma density >1.5 × 10 11/cm 3 and a plasma uniformity of approximately 11% was obtained at 9 kW of RF power and 15 mTor Ar using this internal ICP source,
which is applicable to FPD processing. 相似文献
3.
To deposit copper seed layer on ultra large scale integration devices, a large-area (Ø 378 mm) electron cyclotron resonance plasma has been generated by using permanent magnets-embedded Lisitano antenna. The plasma source operates in the pressure range of 0.2–1.5 mTorr with microwave power range of 500–2,000 W. By using a Langmuir probe, the electron density and temperature have been measured near the DC sputter target position. Measurements indicate argon plasmas having electron densities of ~5 × 10 10/cm and electron temperatures of 5 eV with 750 W microwave power at gas pressures of 0.5 mTorr. Using this plasma source and a DC sputter, we obtained excellent conformal copper seed layer with high aspect ratios of 12:1. This is in contrast with conventional methods using magnetron sputter, which has aspect ratios of 2–3:1. Also, improvements are observed in the smoothness (root mean square roughness of 1.345 nm), uniformity (2.5 % at 300 mm wafer), and sidewall symmetricity (more than 95 %) of the copper seed layer. 相似文献
4.
Electrical and plasma properties of a U-shaped internal inductively coupled plasma (ICP) source with/without a Ni-Zn ferrite
module installed above the ICP antenna were investigated. By installing the ferrite module on the antenna, the increase of
plasma density and the decrease of plasma potential could be observed. The increase of plasma density was related to the efficient
inductive coupling to the plasma by concentrating the induced magnetic field between the antenna and the substrate. At 800 W
of ICP power and 20mTorr Ar, a high density plasma on the order of 4.5′10 11/cm 3 could be obtained. 相似文献
5.
The expansion of an oxygen low-pressure microwave plasma was investigated in order to determine the optimal plasma parameters for the growth of functional oxide semiconductors. Langmuir probe measurements show that the electron density ( n e ) increases with the injected power up to a saturation value of 3.0 × 10 9 cm ?3 determined at 10 mTorr while electron temperature ( T e ) remains constant at a value of 1.5 eV. When pressure is varied, n e shows a maximum value at a range from 12 to 20 mTorr while T e decreases monotonously with increasing pressure. In addition, both n e and T e decrease with the axial distance from the plasma source. These effects were discussed through the loss mechanisms in the remote plasma. For a pressure of 13 mTorr and at a substrate temperature of 500 °C, plasma enhanced oxidation of pure metallic Ti thin films lead to the formation of a pure TiO 2 anatase phase compared to a mixed phase of TiO 2 and TiO in the absence of plasma activation. For Mn thin films, the exposure to oxygen remote plasma led to the formation of MnO 2 as opposed to obtaining Mn 3O 4 when oxidation is performed in the oxygen gas ambient. Remote plasma processing was thus found to provide selective pathways to control oxidation states, stoichiometry and phase composition of technologically attractive oxide thin films. 相似文献
6.
Effects of radio frequency (RF) source power (plasma density) on silicon carbide etching are examined with variations in RF bias power, pressure, O 2 fraction, and gap spacing. The etching was conducted in a C 2F 6 inductively coupled plasma. Depending on parameters or plasma conditions, the etch rate varied quite differently. When the source power was varied, the bias power (ion energy) was strongly involved in determining the relative variation in the etch rate. Complex interactions between the parameters were ascertained by means of a predictive model. The model was obtained by using a neural network in conjunction with a 2 5 full factorial experiment. Model behaviors were consistent with experimental ones. By correlating the etch rate to the DC bias, it was identified that the source power effect on the etch rate is significantly enhanced as the DC bias is maintained at relatively low values. 相似文献
7.
This paper deals with the self-consistent determination of the rf field amplitude for sustaining the steady-state collision-dominated weakley ionized plasmas in the bulk of the rf discharge and of the time-resolved behavior of the isotropic part of the distribution function as well as of relevant macroscopic quantities in plasmas whose particle loss is dominantly determined by electron attachment. The strict timeresolved treatment is based on the nonstationary Boltzmann equation of the electrons and its numerical solution including, apart from electron number conservative collision processes, the electron attachment and ionization. The investigations are related to an rf plasma in a model gas and in SF 6 and are performed for reduced rf field frequencies around 10 MHz Torr –1 which are of particular interest from the point of application of rf discharges for plasma processing. The numerical results show that a large field amplitude of around 160 V cm –1 Torr –1 is necessary to maintain the discharge and that the isotropic distribution, the relevant collision frequencies for attachment and ionization, and the electron density undergo a large modulation during a period of the rf field. 相似文献
8.
A simple, rapid, and sensitive liquid chromatography–mass spectrometric (LC–MS) method was developed and validated for the determination of isoniazid in dog plasma. Plasma samples were deproteined with methanol and separated on a C 18 column interfaced with a single quadrupole mass spectrometer, using 0.1% formic acid–acetonitrile (91:9 v/v) as mobile phase. Detection was performed by positive electrospray ionization with selected ion monitoring at m/ z 138 for isoniazid and 152 for entecavir maleate internal standard. Linearity was obtained over the range of 25–5,000 ng mL ?1, with a lower limit of quantification of 25 ng mL ?1. The intra- and inter-day precision was less than 2.7% in terms of relative standard deviation. Accuracy, expressed as relative error, ranged from ?2.0 to 8.0%. Plasma samples were analysed within 5 min. The method was successfully applied to the evaluation of the pharmacokinetics of isoniazid in dog plasma. 相似文献
9.
High performance liquid chromatography coupled with resonance light scattering detection was developed for separation and determination of heparin in plasma. A good chromatographic separation was achieved using an aminex HPX-87H column (300 mm × 7.8 mm, 9 μm) and a mobile phase of 5.0 mmol L ?1 H 2SO 4 at the flow rate of 0.5 mL min ?1. The enhanced resonance light scattering signals were derived from a large aggregate formation between heparin and cetyltrimethylammonium bromide used as the molecular recognition probe. The parameters of the post-column reaction (pH, concentration and flow rate of the reagent, length of the reaction coil, and temperature) were optimized. The limit of detection for heparin in plasma was 0.2 mg L ?1. The method has been applied to the determination of heparin in dialysis patient plasmas. 相似文献
10.
The free electron concentration in hydrogen and chemically active plasmas in H 2 + SiF 4 and H 2 + GeF 4 mixtures was measured by microwave interferometry. The investigations were carried out under conditions of a RF capacitive-coupled discharge at a pressure of 1 Torr. In hydrogen plasma the concentration of free plasma electrons is 1.5 ± 0.03 × 10 12 cm ?3. When the fluoride is added to the hydrogen plasma, the electron concentration is reduced to 1.1 ± 0.05 × 10 12 cm ?3 for SiF 4 and 9.8 ± 0.05 × 10 11 cm ?3 for GeF 4. It is suggested that the main mechanism responsible for reducing the concentration of free electrons is the mechanism of dissociative attachment of electrons to SiF 4 and GeF 4 molecules. The difference in the electron concentration for these mixtures is due to the difference in the electron-acceptor ability of the SiF 4 and GeF 4 molecules determined by the affinity for the electron. 相似文献
11.
BCl 3/Ar and BCl 3/N 2 plasma chemistries were compared for patterning of InP, InAs, InSb, InGaAs, InGaAsP, and AlInAs. Under electron cyclotron
resonance conditions etch rates in excess of 1 μm/min can be achieved at room temperature with low additional rf chuck power
(150 W). The etch rates are similar for both chemistries, with smoother surface morphologies for BCl 3/Ar. However, the surfaces are still approximately an order of magnitude rougher (as quantified by atomic force microscopy)
than those obtained under the same conditions with Cl 2/Ar. InP surfaces etched at high BCl 3-to-Ar ratios have measurable concentrations of boron-and chlorine-containing residues. 相似文献
12.
High performance liquid chromatography coupled with resonance light scattering detection was developed for separation and determination of heparin in plasma. A good chromatographic separation was achieved using an aminex HPX-87H column (300 mm × 7.8 mm, 9 μm) and a mobile phase of 5.0 mmol L−1 H2SO4 at the flow rate of 0.5 mL min−1. The enhanced resonance light scattering signals were derived from a large aggregate formation between heparin and cetyltrimethylammonium bromide used as the molecular recognition probe. The parameters of the post-column reaction (pH, concentration and flow rate of the reagent, length of the reaction coil, and temperature) were optimized. The limit of detection for heparin in plasma was 0.2 mg L−1. The method has been applied to the determination of heparin in dialysis patient plasmas. 相似文献
13.
An investigation of etching behaviors for Mo and Al 2O 3 thin films in O 2/Cl 2/Ar inductively coupled plasmas at constant gas pressure (6 mTorr), input power (700 W) and bias power (200 W) was carried out. It was found that an increase in Ar mixing ratio for Cl 2/Ar plasma results in non-monotonic etching rates with the maximums of 160 nm/min at 60 % Ar for Mo and 27 nm/min at 20 % Ar for Al 2O 3. The addition of O 2 in the Cl 2/Ar plasma causes the non-monotonic Mo etching rate (max. 320 nm/min at 40–45 % O 2) while the Al 2O 3 etching rate decreases monotonically. The model-based analysis of etching kinetics allows one to relate the non-monotonic etching rates in Cl 2/Ar plasma to the change in the etching regime from the ion-flux-limited mode (at low Ar mixing ratios) to the neutral-flux-limited mode (for high Ar mixing ratios). In the Cl 2/O 2/Ar plasma, the non-monotonic Mo etching rate is probably due to the change in reaction probability. 相似文献
14.
The TiO 2 etching characteristics and mechanisms in HBr/Ar and Cl 2/Ar inductively-coupled plasmas were investigated under fixed gas-mixing ratio and bias power conditions. It was found that
in both systems, an increase in gas pressure from 4 to 10 mTorr results in a non-monotonic TiO 2 etching rate, while a variation of input power in the range 500–800 W causes a faster-than-linear acceleration of the etching
process. Plasma diagnostics performed by Langmuir probes and zero-dimensional plasma modeling provided data on plasma parameters,
steady-state densities, and fluxes of the active species on the etched surface. The model-based analysis of the etching mechanism
showed that for the given set of processing parameters, the TiO 2 etch kinetics correspond to the transitional regime of ion-assisted chemical reaction in which a chemical-etch pathway dominates. 相似文献
15.
In the wavelength range from 200 up to 1000 nm, optical emission from electronically excited fragments (CN, CH, NH, C 2, H 2, N 2, N 2+, and H-Balmer) is detected when aniline plasmas are generated in a multi-dipolar microwave reactor. The optical emission spectrum monitored in very low-pressure conditions (~?1 mTorr) shows important characteristics. The H α, H β and CN species are the most radiating systems and according to the NH/N 2 intensity ratio, two different operating regimes are observed suggesting a change in the reaction pathways. These two regimes are correlated to changes of the plasma characteristics (electron temperature and density) deduced from Langmuir probe measurements. The plasma thermodynamic state is quantified by implementing numerical simulation codes for synthetic spectra calculations. The rovibrational temperatures ( Tr, Tv) are determined for some neutral species (CN, CH). The obtained values of Tr and Tv show the non-local thermodynamic equilibrium of the vibrational and rotational states ( Tr?<? Tv). Moreover, the very low pressure aniline-based plasmas deviate substantially from the Boltzmann distribution. Correlation between the optical emission data and the solid phase analysis allows proving that the in situ characterization of the plasma phase is an important predictive tool of physico-chemical properties of the film. From these correlated data, we deduce preponderant chemical reaction pathways which help to better understand the plasma generation. Relative contributions of the dehydrogenation of C–H and N–H groups are established in order to deduce the leading initiation reaction for H-Balmer line formation. 相似文献
16.
The effects of HBr/Ar and HBr/Cl 2 mixing ratios in the ranges of 0–100% Ar or Cl 2 on plasma parameters, densities of active species influencing the dry etch mechanisms were analyzed at fixed total gas flow
rate of 40 sccm, total gas pressure of 6 mTorr, input power of 700 W and bias power of 300 W. The investigation combined plasma
diagnostics by Langmuir probes and the 0-dimensional plasma modeling. It was found that the dilution of HBr by Ar results
in maximum effect on the ion energy flux with expected impact on the etch rate in the ion-flux-limited etch regime, while
the addition of Cl 2 influences mainly the relative fluxes of Br and Cl atoms on the etched surface with expected impact on the etch rate in the
reaction-rate-limited etch regime. 相似文献
17.
A Langmuir probe investigation of Ar/O 2/Al(OPr 1) 3 plasmas is described. The probe contamination depends on the probe position and the flow of tine carrier gases. Whereus far from the working gas inlet characteristics without any hysteresis were obtained, near to the inlet undisturbed characteristics were recorded only for small gas flows or a low vapor pressure of the precursor. Condensation of the precursor ai the probe surface prior to the plasma excitation was the main source of probe contamination. A decrease ire the plasma potential with respect to the ground observed during experiments was attributed to the formation of a dielectric film on the rf electrode. This resulted in a self-bias responsible for the decrease in plasma potential. 相似文献
18.
For the purpose of realizing a low-cost production process of silane (SiH 4) gas, we have proposed the high-rate etching of metallurgical-grade Si by narrow-gap microwave hydrogen plasma. In this paper, effect of hydrogen gas flow rate (0–10 L/min) on the etch rate has been investigated and correlated with the relative variation of hydrogen-atom density estimated by actinometry. By decreasing hydrogen gas flow rate, the etch rate gradually increases up to the maximum value of 11 μm/min at 2 L/min. This increase is well correlated with the increase of hydrogen-atom density due to the longer residence time of hydrogen molecules in the plasma. On the other hand, when the gas flow rate is lower than 2 L/min, the etch rate abruptly decreases with decreasing gas flow rate in spite of the increase of hydrogen-atom density. From the surface observations and Raman measurements, it is found that the decrease in etch rate in the lower flow rate range is attributed to the formation of microcrystalline Si particles due to the decomposition of generated-SiH 4 molecules in the plasma. 相似文献
19.
An investigation of etching mechanism of low-temperature SiO 2 thin films in CF 4/Ar/O 2 inductively coupled plasmas at constant input power (900 W) and bias power (200 W) was carried out. It was found that that the variations of Ar/O 2 mixing ratio (0–50 %) at constant 50 % CF 4 fraction as well as the change in gas pressure (4–10 mTorr) resulted in non-monotonic SiO 2 etching rates. The zero-dimensional plasma model with Langmuir probe diagnostics data provided the detailed information on formation-decay kinetics for plasma active species. The model-based analysis of etching kinetics showed that these effects were not connected with the non-monotonic change of fluorine atom density (as was found in several works for the binary CF 4/O 2 system), but resulted from the decrease in reaction probability and with the transition from neutral-flux to ion-flux-limited regimes of ion assisted chemical reaction. 相似文献
20.
The plasma treatment of self-assembled monolayers of octadecyl mercaptan on gold substrates has been investigated as a model for oxygen atom effects on polymers. Both O 2 and H 2O low pressure gas plasmas have been used. X-ray photoelectron spectroscopy has revealed that the two plasma treatments differ from each other in the extent of oxidation and etch rate with O 2 being the more aggressive plasma. The results have confirmed that the plasma modification of organic surfaces involves a balance between surface oxidation and surface etching. The well-defined structure of the monolayer enables quantitation of these atom-substrate reactions. © 1998 John Wiley & Sons, Ltd. 相似文献
|