In situ Heating and Thermal Effects in Auger Electron Spectroscopy for GaN

An in situ heating system was built for the Auger electron spectroscopy to investigate the thermal effect of Auger lines. A GaN sample was studied in this system. The kinetic energy of Ga LMM and MVV Auger lines were observed to shift negatively with temperature increasing. By using ab initio calculation, the theoretical Ga MVV Auger line shape was fit, which well reflects the inner property of the line. The Auger shift with heating is related with the valence electron rearrangement in the thermal expansion of the local bonds.

Formation of Charged Particle Tracks in Solids

A criterion for formation of etchable tracks in solids is suggested using the well-known concepts of ionization and thermal spikes, diffusion process with useful and justified assumptions, and present or published experimental and theoretical investigations on the same subject. The suggested criterion is useful for a wide spectrum of researchers including development and applications of track recording materials, ions implantation, sputtering and other areas, which include interactions of charged particles with solids.

Application of Auger electron spectroscopy in lithium-ion conducting oxide solid electrolytes

Garnet-type oxide solid electrolytes are the critical materials for all-solid-state lithium ion batteries.Nanoscale spectroscopic analysis on solid electrolytes plays a key role in bridging the gap between microstructure and properties.In this work,Auger electron spectroscopy(AES),which can directly detect lithium element and distinguish its valence state,was applied to characterize the garnet-type Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6O12)(LLZTO).Different spectroscopy parameters were evaluated and optimal acquisition conditions were provided.Electron induced precipitation of lithium metal from LLZTO was observed.By exploring the influence factors of precipitation and combining transmission electron microscopy(TEM)and focused ion beam(FIB)experiments,the underlying mechanism of the phenomenon was revealed and previous controversy was resolved.The analysis method was also extended to other types of solid electrolytes,and this work provides a reference for future in-depth research on the structure-property relationship of solid electrolytes using AES.

Study of Carbon Contaminated Epitaxial Silicon

The properties of the carbon contaminated silicon epitaxial layer and its surface have been studied by means of JAMP-10 Auger electron microprobe and JEM-2000FX transmission scanning electron microscope. The results show that the fog defects on the surface are due to carbon contamination. The existence of SiC in the silicon epitaxial layer has been identified by the electron diffraction analysis.

Study the Characteristics of Titanium Oxide Hydrogen Ion Sensor Using XRD and AES

We study the extended gate ion sensitive structure,and deposit the titanium oxide (TiO_2) thin film on p-type (100) silicon substrate.The device of the hydrogen ion sensing structure is TiO_2/Si-substrate,and a commercial device of the metal oxide semiconductor field effect transistor (MOSFET) is connected to the separative sensing device.The sensitivity and linearity are measured under different work pressures.When the mixed ratio of Ar/O_2 is 80 ml·min^(-1)/20 ml·min^(-1),the work pressure is 4 Pa,the sputtering power is 150 W,and the sputtering time is two hours,the better sensing properties of the sensitivity and linearity are 36.49 mV/pH and 0.99654,respectively.However,some instruments are analyzed the surface of TiO_2 membrane,such as X-ray diffraction (XRD) and Auger Electron Spectrometer (AES).The characteristics of TiO_2 thin film can be demonstrated.

Study on Relationship between InGaAsP/InP LPE Wafer Morphology,Interface Property and Device Characteristics

Five kinds of InGaAsP/InP heterostructure materials grown with LPE have been measured by means of Auger electron analysis, X-ray double-crystal diffraction, selective etching and surface morphology analysis. The relation between crystal mismatch and interface property of such materials has been studied and the results could be understood in terms of the growth kinetics at the heterojunction interface. The comparison of the characteristics of the electronic and optoelectronic devices fabricated with the wafers under different interface properties has been carried out. And it also has been demonstrated that the wafer surface morphology changes with the compositional gradation in a certain relationship.

Compositional study of δ-NbN film by Auger electron microscopy

The chemical stoichiometry on the surface of superconducting δ-NbN thin films is of great importance for their application.Here,we fabricated the δ-NbN thin films on SiO2/Si substrate by DC sputtering method.The film was characterized using X-ray diffraction(XRD) and atomic force microscopy(AFM).Transport properties were measured to reveal the field dependent superconducting transition temperature.Both XRD and electrical measurement show high crystallinity of δ-NbN phase.A homogeneous and smooth surface morphology was measured by AFM.Auger electron spectroscopy(AES) was applied to analyze the composition along the depth of the film.The evolution of Auger peak profile,heights and nitride stoichiometry at the film surface is discussed.The current study provides a more thorough understanding of complex chemical compositions of δ-NbN thin films.

Structure and Properties of TiB_2 Thin Films Deposited at Low Temperatures Using RF Magnetron Sputtering

The TiB2 thin films were deposited on steel substrates using RF magnetron sputtering technique with the low normalized substrate temperature （0.1〈Ts/Tm〈0.2）. Microstructure of these films was obtained by field emission scanning electron microscope （FESEM） and the grazing incidence X-ray diffraction （GIXRD） characterization, while the composition of films was obtained using Auger emission spectroscopy （AES） analysis. It was found that the TiB2 thin films were overstoichiometric with the B/Ti ratio at 2.33 and the diffusion of Ti and B atoms on the substrate surface was greatly improved at 350 ℃. Moreover, a new dense structure, named ＂equiaxed＂ grain structure was observed by FESEM at this substrate temperature, Combined with FESEM and AES analysis, it was suggested that the ＂equiaxed＂ grain structure was located in Zone 2 at the normalized substrate temperature as low as 0.18.

Influence of Aluminum Ions Implantation on Corrosion Behavior of Zircaloy-2 Alloy in 1 M H_2SO_4

The specimens were implanted with aluminum ions with fluence ranging from 1× 10^16 to 1× 10^17 ions/cm^2 to study the effect of aluminum ion implantation on the aqueous corrosion behavior of zircaloy-2 by metal vapor vacuum arc source （MEVVA） at an extraction voltage of 40 kV. The valence states and depth distributions of elements in the surface layer of the samples were analyzed by X-ray photoelectron spectroscopy （XPS） and Auger electron spectroscopy （AES）, respectively. Transmission electron microscopy （TEM） was used to examine the microstructure of the aluminum-implanted samples. Glancing angle X-ray diffraction （GAXRD） was employed to examine the phase transformation due to the aluminum ion implantation. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted zircaloy-2 in a 1 M H2SO4 solution. It is found that a significant improvement was achieved in the aqueous corrosion resistance of zircaloy-2 implanted with aluminum ions. Finally, the mechanism of the corrosion behavior of aluminum- implanted zircaloy-2 was discussed.

Surface Analysis of ZIRLO Alloy Implanted with Carbon

ZIRLO alloy specimens were implanted with carbon ions with fluence range from 1×10 16 to 1×10 18ions·cm -2, using a MEVVA source at an extraction voltage of 40 kV at maximum temperature of 380 ℃. The surfaces of the implanted samples were then analyzed and the TRIM 96 computer code was used to simulate the depth distribution of carbon. The valences of elements in the implanted surface of ZIRLO alloy were analyzed by X-ray photoemission spectroscopy (XPS); and then the depth distributions of the elements on the surface of the samples were obtained by Auger electron spectroscopy (AES). Scanning electron microscopy (SEM) was used to examine the micro-morphology of implanted samples. Glancing angle X-ray diffraction (GAXRD) at 0.30 incident angles was employed to examine the phase transformations of implanted samples. It shows that the as-received ZIRLO alloy is mainly composed of hexagonal alpha zirconium, as for implanted samples, there appeared hexagonal zirconia (H-ZrO_ 0.35) and sigma zirconium carbide (δ-Zr_3C_2), and the δ-Zr_3C_2 increased when increasing the fluence. When the fluence reached 1×10 18 ions·cm -2, the concentration of δ-Zr_3C_2 is the maximum in all the samples. The micro-morphology of implanted samples are similar, there are many pits with diameters ranging from 1 to 3 μm on the implanted surfaces.

Effect of copper ions implantation on the corrosion behavior of ZIRLO alloy in 1 mol/L H_2SO_4

In order to study the effect of copper ion implantation on the aqueous corrosion behavior of ZIRLO alloy, specimens were implanted with copper ions with fluences ranging from 1×10^16 to 1×10^ ions/cm^2, using a metal vapor vacuum arc source （MEVVA） at an extraction voltage of 40 kV, The valence states and depth distributions of elements in the surface layer of the samples were analyzed by X-ray photoelectron spectroscopy （XPS） and Auger electron spectroscopy （AES）, respectively. Glancing angle X-ray diffraction （GAXRD） was employed to examine the phase transformation due to the copper ion implantation. The potcntiodynamic polarization technique was used to evaluate the aqueous corrosion resistance of implanted ZIRLO alloy in a 1 mol/L H2SO4 solution. It was found that a significant improvement was achieved in the aqueous corrosion resistance of ZIRLO alloy implanted with copper ions when the fluence is 5×10^16 ions/cm^2. When the fluence is 1×10^16 or 1×10^17 ions/cm^2, the corrosion resistance of implanted sanaples was bad. Finally, the mechanism of the corrosion behavior of copper-implanted ZIRLO alloy was discussed.

Three-dimensional evaluation of inclusion particles in steel

The estimation of inclusion particles has a relation close to the control of steel grain growth as well as the production of clean steel.In present study,the electrolytic extraction methods using nonaqueous electrolyte have been examined for the extraction of various inclusion particles,in order to evaluate their three-dimensional morphologies and compositional segregations.The cross section of fine inclusion particle,which was prepared by focused ion beam method,was qualitatively analyzed using Auger electron spectroscopy.From the results obtained by this method,the formation mechanism of complex inclusion particle could be explained clearly.

PREFERENTIAL SPUTTERING OF Cu_(76)Ni_(15)Sn_9

Using collection film technique combined with Auger electron spectroscopy is analysis, the preferential sputtering of the ternary alloy Cu76Ni15Sn9 bombarded with 27 keV Ar+ at normal incidence is studied. After bombardment, the target surfaCe is examined with SEM, and the surface composition of different topographical feature areas is measured with electron probe micrthanalyser (EPMA). The experiment results show that Cu atoms are preferentially ejected compared with Ni atoms, and Sn atoms come third within the ejection angle range from 0° to 60°. The results are discussed from the viewpoint of sputtering from a very rough surface.

Effect of Mg addition on temper embrittlement in 2.25Cr–1Mo steel doped with 0.056% P–Mg segregation behavior at grain boundary

To verify the microalloying function and segregation behavior of trace Mg at grain boundary in steel,the 2.25Cr–1Mo steel doped with 0.056%P containing different Mg contents was refined with a vacuum-induction furnace.The effects of trace Mg addition on the temper embrittlement susceptibility of 2.25Cr–1Mo steel were studied by step-cooling test and the segregation behavior of Mg at grain boundary was explored by Auger electron spectroscopy.It is shown that P-induced temper embrittlement susceptibility can be reduced after subjecting to step-cooling treatment with trace Mg addition,mainly benefited from the segregation of Mg at grain boundary.This segregation can decrease the segregation amounts of P and S,especially for P,and increase the grain boundary cohesion,reducing the adverse effect on temper embrittlement caused by P and S.

Chemical composition and Mott-Schottky analysis of passive film formed on G3 alloy in bicarbonate/carbonate buffer solution

The chemical composition and semi-conductive properties of passive film on nickel- based alloy （G3 alloy） in bicarbonate/carbonate buffer solution were investigated by Auger electron spectroscopy （AES）, X-ray photoelectron spectroscopy （XPS）, elec- trochemical impedance spectra （EIS） and Mott-Schottky plot. AES and XPS results showed that the passive film appeared double-layer structure, in which the inner film was composed of nickel oxide, the mixed nickel-chromium-molybdenum-manganese oxides were the major component of the outer film. The electrochemical results revealed that the factors including frequency, potential, time, temperature and pH value can affect the semi-conductive property, the doping densities decreased with increasing potential and pH value, prolonging time and decreasing temperature. According to the above results, it can be concluded that the film protection on the substrate was enhanced with increasing potential and pH value, prolonging time and decreasing temperature.