Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 5

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

EXAFS Determination of Bond Lengths in Zn_{1-x}Fe_{x}S Ternary Alloys

100%
Iwanowski R. J., Ławniczak-Jabłońska K.
Acta Physica Polonica A
|
1997
|
vol. 91
|
issue 4
797-801
EN
Studies of local atomic structure in the zinc-blende Zn_{1-x}Fe_{x}S (x=0.11-0.50) diluted magnetic semiconductors with the use of the EXAFS technique are reported for the first time. They include the K-edge EXAFS measurements for both cationic elements (Zn, Fe). The experiment was carried out at room temperature in the transmission mode using synchrotron radiation of the DCI storage ring in Orsay, France. A detailed EXAFS analysis for different crystal compositions (x) gave a convincing evidence for a bimodal distribution of the nearest-neighbour interatomic distances in Zn_{1-x}Fe_{x}S within the iron solid-solubility limit. It has also revealed, within the accuracy of this method, constancy of both the nearest-neighbour cation-anion distances (i.e. Zn-S and Fe-S) in the composition range studied.
2
Content available remote

Adsorption of Oxygen on HF-Etched Si(111) Surfaces: XPS Study

100%
Iwanowski R. J., Sobczak J. W.
Acta Physica Polonica A
|
1997
|
vol. 91
|
issue 4
793-796
EN
X-ray photoelectron spectroscopy studies of the Si(111) surfaces, after dilute HF etching and methanol rinse, are reported. These included a detailed analysis of the main core-levels (Si 2p, O 1s) and the valence band spectra. The observed asymmetry of the O 1s lines was attributed to two contributing subpeaks: the main (1) and the minor one (2), shifted ≈ 1.5 eV to higher binding energies. Their relative intensity was found to depend on the air exposure time and on the take-off angle. The peaks were assigned to two different positions of surface oxygen: (1) O chemisorbed with methoxy group, (2) bridging O atom. The valence band X-ray photoelectron spectroscopy spectra reveal the influence of surface states induced by the "chemisorbed O"-Si bond.
3
Content available remote

X-Ray Photoelectron Study of Yb-Doped InP

81%
Iwanowski R. J., Sobczak J. W., Kaliński Z.
Acta Physica Polonica A
|
1997
|
vol. 91
|
issue 4
809-813
EN
X-ray photoelectron spectra of core levels are reported for InP:Yb. Crystalline InP, doped with Yb to a level of 0.5 at.%, was grown by the synthesized solute diffusion method. An analysis of the core-level spectra of the constituent components, i.e. In 3d_{5/2} and P 2p, revealed a minor influence of the surface oxide species, mainly in the phosphate-like form. The spectrum of the Yb 4d core level was also recorded. The energy of the Yb 4d_{3/2} peak was found identical to that in Yb metal, whereas the 4d_{5/2} peak was found to be shifted to higher binding energies. This effect was found comparable to the case of advanced oxidation of Yb thus confirming its high reactivity, even as a bulk dopant. The data give also a rare experimental example of detection of bulk dopant atoms in a semiconductor matrix by X-ray photoelectron spectroscopy at the limit of detectability.
4
Content available remote

Chemical Shifts at K-Absorption Edges of Transition Metals Admixed To ZnS and ZnSe

81%
Iwanowski R. J., Ławniczak-Jabłońska K., Traverse A.
Acta Physica Polonica A
|
1997
|
vol. 91
|
issue 4
803-808
EN
This paper gives the experimental evidence of systematic X-ray K-absorption edge studies in an effort to analyse the effect of cation chemical shift in the group of compounds type Zn_{1-x}M_{x}A (M = Mn, Fe, Co, Ni; A = S, Se). The observed chemical shift was found practically independent of the choice of anion, whereas it revealed a noticeable decrease when passing from Mn to Zn. The effect was ascribed to the change of the 3d shell occupation. The calculations of the effective cation charge (based on the theoretical approach of Kitamura and Chen, 1991) have shown that in the case of transition metals admixed to ZnS and ZnSe there is a contribution of the 3d electrons to the overall charge transfer, which indicates that the ability of 3d electrons to participate in predominantly ionic bond decreases with 3d orbit filling.
5
Content available remote

X-Ray Photoelectron Spectroscopy and Optical Reflectivity Studies of Si Surfaces Prepared by Chemical Etching

81%
Iwanowski R. J., Sobczak J. W., Kowalski B. J.
Acta Physica Polonica A
|
1994
|
vol. 86
|
issue 5
825-830
EN
Complementary X-ray photoelectron spectroscopy and optical reflectivity studies of crystalline Si(111) surfaces prepared by two different wet chemical etching processes were performed. These included aqueous HF solution etch or diluted CP-4 bath. Optical reflectivity spectra of Si surfaces, measured in the range 3.7-11 eV, were found strongly dependent on the applied etching process. Analysis of the core level X-ray photoelectron spectroscopy data has shown similarity of the surface structure, irrespectively of the etching procedure. Finally, comparison of optical reflectivity and valence band X-ray photoelectron spectra revealed a qualitative correlation between them indicating dominant influence of the bulk (here, the subsurface region containing polishing-induced defects) in the case studied. This paper is the first one which presents correlations between optical reflectivity and X-ray photoelectron spectroscopy data for Si and thus illustrates a bulk sensitivity of both techniques considered.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.