Influence Of Synchrotron Radiation Research Articles

Modelling the Energy Spectra of Radio Relics

Radio relics are diffuse synchrotron sources that illuminate shock waves in the intracluster medium. In recent years, radio telescopes have provided detailed observations about relics. Consequently, cosmological simulations of radio relics need to provide a similar amount of detail. In this methodological work, we include information on adiabatic compression and expansion, which have been neglected in the past in the modelling of relics. In a cosmological simulation of a merging galaxy cluster, we follow the energy spectra of shock accelerated cosmic-ray electrons using Lagrangian tracer particles. On board of each tracer particle, we compute the temporal evolution of the energy spectrum under the influence of synchrotron radiation, inverse Compton scattering, and adiabatic compression and expansion. Exploratory tests show that the total radio power and, hence, the integrated radio spectrum are not sensitive to the adiabatic processes. This is attributed to small changes in the compression ratio over time.

Mass loss by SU-8 polymer under X-ray irradiation

The principal volatile products forming in air degradation of SU-8 polymer under influence of synchrotron radiation in the wavelength range of 2.5–0.25 A have been studied. The material degradation products such as hydrogen, acrolein, acetone, allyl alcohol, benzene, and methyl formate have been identified, as well as atmospheric products. However, the most often products of outgassing are water and carbon oxide molecules, which contribute to the mass loss of the polymer irradiated.

Influence of synchrotron radiation on morphological features of a polymethylmetacrilate thin film

The interaction of polymethylmetacrilate (PMMA) hard films with synchrotron radiation (SR) has been studied by atomic force microscopy (AFM). It has been found that the roughness changes from 1.85 to 2.98 nm with an increase in the irradiation time for the selected beam with the energy corresponding to the hard X-ray region λ = 0.2 nm. The roughness decreases from 6.41 to 2.36 nm with an increase in the irradiation time from 1 to 17 min when photons with a lower energy are used. The interaction of radiation with PMMA leads to the appearance of nanohillocks, the average diameter and height of which depend directly proportionally on the spectral composition and SR exposure time. The revealed effects of interaction of synchrotron radiation with PMMA will help to correct the X-ray lithography conditions in electron engineering (PMMA is the basis for X-ray resist) and will allow one to control the roughness degree of the PMMA surface that is the basis for intraocular lenses.

Investigation of radiation-induced surface temperature of thick polymer layers under influence of synchrotron radiation

Radiation-induced heating of thick polymer layers under synchrotron radiation (SR) in a process of formation of microstructures with high aspect ratio has been investigated with the use of film thermoresistors.

Synchrotron radiation photochemistry of copper phthalocyanine layers

The influence of synchrotron radiation (SR) in vacuum-deposited layers of copper phthalocyanine (CuPc) and the influence of the following vacuum thermal development in the positive and negative exposed CuPc layers were investigated by EPR, Raman spectroscopy, UV-visible spectroscopy, X-ray diffraction, mass spectrometry using Knudsen cell. It was established that the layers of α-CuPc possessed EPR anisotropy. The anisotropy decreased with an increase of SR exposure and changed for negative exposed layers and for layers heated at development temperature. For positive exposed and unexposed layers of CuPc, the α → β-phase transition occurred at development temperature, but this process was not observed at development of negative exposed layers. Mass spectra of evaporated CuPc molecules from unexposed and positive exposed layers were similar. Only for negative exposed layers the additional protonated molecules of CuPc were recorded in mass spectra. Unexposed, positive exposed and negative exposed CuPc layers had different temperature dependencies of pressure of evaporated molecules. All measured spectra and dependencies were analysed and SR photochemistry of CuPc layers was discussed.

The use of SR for the creation of a topology in layers of metal phthalocyanines

The influence of synchrotron radiation (SR) on vacuum-deposited layers of copper and aluminium phthalocyanines is investigated. For the creation of patterns in these layers X-ray radiation exposure and vacuum thermal development were used. It was established, that the layers of copper phthalocyanine (CuPc) possess the properties of both positive and negative vacuum X-ray resist upon radiation exposures of 5 kJ/cm 3 and 35 kJ/cm 3, respectively. The layers of aluminium phthalocyanine (AlPcX, where X = Cl, F, OH) possess the properties of only negative vacuum X-ray resists. The possibility of the creation of a submicron topology in layers of metal phthalocyanines has been demonstrated.

Photon energy dependence of synchrotron radiation induced growth suppression and initiation in Al chemical vapor deposition

The influence of synchrotron radiation (SR) irradiation on Al chemical vapor deposition has been studied as a function of SR photon energy. A clear difference between inner shell electron excitation and valence electron excitation is observed. Suppression of Al growth on the Si surface is found to be induced effectively by the excitation of the inner shell electrons, while initiation of the growth on the SiO 2 surface is caused by the excitation of the valence electrons.

Influence of synchrotron radiation on corrosion at the boundary of cooling water and metals-II. A6063, A2219, SiO 2 film on aluminum and stainless steel 316L

Radiation damage due to synchrotron radiation has been studied at the boundary of cooling metals; aluminum alloys, A2219 and A6063; stainless steel 316L and SO 2 film about 10 micro thick on the inside of an aluminum alloy pipe. The damage was evaluated utilizing dissolved ion density of the irradiated sample water from the pure water circulating system. At 1000 h operating time (∼ a time integrated beam current of 6 Ah, ∼ 3.5 × 10 22 photons) for Al and Si, and at 1700 h (10 Ah, 4.8 × 10 22 photons) for stainless steel), the dissolved ion densities are: Ni of the order of 1 mg l −1; Fe of the order of 0.1 mg l −1 and Cr of the order of 0.01 mg l −1 from the stainless steel: Si from SiO 2 film and Alfrom aluminum alloys of the order of 0.1 mg l −1. The data showed that these materials are suitable for vacuum chambers and components exposed to synchrotron radiation and cooling water. The order of magnitude of the dissolved ion density approximately coincides with that of the free energy of the formation of the oxides. SiO 2 coating film functions as a protecting film from the dissolving Al ions. The oxides or hydroxides on the aluminum alloys and stainless steel also function as protecting films from the dissolving ions of the base materials. The stability of the oxide film is higher than that of hydroxide. Therefore oxide film coating, not hydroxide film, is necessary to obtain the stability of the base material against irradiation.

Influence of synchrotron radiation on corrosion at the water—metal boundary

Radiation damage due to synchrotron radiation has been studied at the boundary of cooling water and metal related to vacuum chambers: oxygen free copper (OFC). The damage was evaluated by measuring the dissolved ion concentration in water, sampled from the pure water circulating system with a sample pipe (10 mm in inner diameter and 1 mm in thickness), irradiated by synchrotron radiation with photons (40–700 keV) of the order of 10 16 photons (MeV mA s) -1 in the TRISTAN e +e - colliding ring (bending radius of 246 m and beam energy of 29 GeV). OFC with an irradiated surface area of 10 mm 2 showed a Cu ion concentration of 6 mg 1 -1 after 1.3 A h irradiation (800 h operation, 5.3 x 10 20 photons mm -2). The ion concentration showed an increasing rate of t 1 3 − 1 2 before 500 h. After 500 h operation, it was roughly proportional to t. The time dependence of the concentration of the non-irradiated sample was t 1 3 before 10 3 h. The concentration increased from 0.01 before 10 3 h to 1 mg l -1 after 10 3 h. The relationship between the free energy of formation and the estimated dissolved ion concentration of OFC together with the one of aluminum alloys, a 10 μm thick silicon dioxide film inside an Al pipe, and stainless steel 316L at 10 A h (the dose of the materials ranging from 4.1 to 5.8 x 10 21 photons mm -2) gives that the higher the free energy of formation, the lower the dissolved ion concentration. Therefore, to obtain a radiation resistant surface, the stable oxide (with higher free energy of formation) should be selected.

Influence of synchrotron radiation on corrosion at the boundary of cooling water and a metal—I. Mo alloy

Corrosion characteristics at the boundary of cooling water and a Mo alloy under synchrotron radiation with an energy range of 30—300 keV, were investigated in the TRISTAN e+e- colliding ring analyzing the dissolving Mo ion density into pure water. The dissolving ion density under irradiation is two orders of magnitude higher than that of the non-irradiated. The ion density for irradiated and non-irradiated Mo increased linearly with the operating time and was 200 mg I −1 after 1800 h and 10 mg I −1 after 800 h, respectively. The resultant reduction of the irradiated Mo surface is 0.17 mm in thickness with 0.8 mm in FWHM of the synchrotron radiation beam.

Resistless inverse projection patterning of aluminum by using synchrotron radiation induced suppression of thermal chemical vapor deposition

The influence of synchrotron radiation (SR) irradiation on the chemical vapor deposition (CVD) of dimethylaluminum hydride (DMAH) on a Si(100) surface carried out using a molecular-beam CVD technique is studied. The thermal CVD reaction is found to be suppressed almost completely by the SR irradiation. This suppression effect continues even after the irradiation is stopped. Auger analysis reveals that the surface composition of the irradiated area is changed to AIC, while pure aluminum is formed on the non-irradiated area. From these facts, we conclude that the suppression is caused by the very thin reaction blocking layer formed by SR-induced CVD. By using this suppression phenomenon, the inverse projection patterning of Al is successfully demonstrated without photolithography.

Synchrotron radiation spectral distribution and dose influence on the surface states at the SiSiO 2 interface

The influence of synchrotron radiation on the surface states at the SiSiO 2 interface is observed based on experimental data received at the “X-ray Topography and Diffractometry” station of the VEPP-3 and VEPP-4 storage rings. Two kinds of MOS-structures were used. Theoretical calculations of such influence were made, and also a theoretical prediction about the dose dependence of such influence was made for the NSRF “Zelenograd”, which will soon be built.

アルミビームダクト冷却管部腐食に対する放射光照射の影響

アルミビームダクト冷却管部腐食に対する放射光照射の影響

Generation of surface states on the SiSiO 2 interface under the influence of synchrotron radiation

A dose dependence analysis of the origin of surface states under the influence of synchrotron radiation has been performed. Quantity estimates of the exposure dose absorbed by the investigated samples, and also analysis of the surface states' relaxation process under thermal treatment have been done. It has been shown that short-time, low-temperature annealing restores the parameters of the samples to the initial level.

Investigations of x-ray exposure using plane scanning mirrors

One of the essential processing problems in x-ray lithography using synchrotron radiation is the relatively small vertical divergence of the radiation. A possible method to enlarge the small exposure field is the application of scanning x-ray mirrors in the grazing incidence region with a reflectivity of about 90% at wavelengths around 10 Å. The theoretical values of the absorbed energy in the x-ray resist as a function of the glancing angle, in the case of a plane mirror, have been compared with experimental results. In order to obtain a homogeneous exposure when scanning the mirror, the velocity profile of the mirror movement has to be adjusted to the change in the reflectivity. Another important aspect in the application of the mirror is the degradation of its surface, due to cracked hydrocarbon products under the influence of synchrotron radiation. Initial experimental results show that this problem is not as severe as previously expected. The investigations show that the application of x-ray mirrors is in fact a useful way to enlarge the exposable area in the case of synchrotron radiation, since the loss in intensity is acceptable and the mirror lifetime is satisfactory.