Photosensitivity of nanoporous glasses and polymers doped with Eu(fod)₃molecules

Abstract

The combined effects of N 2 -implantation at S/D extension and N 2 O oxide on 0.18 µm n-and p-Metal oxide field effect transistors (MOSFETs) were investigated. It is found that for n-channel transistors, V th roll-off and drain-induced barrier lowering (DIBL) are enhanced by nitrogen incorporation through either N 2 O oxide or N 2 -implantation. However, for p-channel transistors, opposite trends are observed for N 2 O oxide and N 2 -implantation. Finally, nitrogen incorporation by either method is found to improve the interface quality for nMOSFETs. While for p-channel transistors, best results are obtained by the combined effects of N 2 O oxide and N 2 -implantation.

Photosensitivity and thermosensitivity of polymers doped with Eu(fod)3 molecules

“…The photoluminescence excitation channel in this case consisted of an LD(D)-400 deuterium lamp and an MDR-12 monochromator with spectral resolution 13.6 nm (λ em = 300 nm) or an NSHU590 UV light-emitting diode (LED) (Nichia Corporation, Japan) with wavelength at the maximum of the luminescence band equal to 380 nm and half-width 0.1 eV, radiation power density at the sample ~0.1 W/cm 2 . The same setup was used in earlier work [8,10,13,14] devoted to the study of the luminescent characteristics of various transparent dielectrics containing Eu(fod) 3 molecules. In the studies of the temperature dependences of the photoluminescence intensity, the uncertainty in establishment of the temperature was no worse than 0.…”

“…The bright luminescence of Eu 3+ ions arising upon excitation of the 5 D 0 → 7 F j transition in the red region of the spectrum may be used for a wide variety of practical applications of these materials [1][2][3][4][5][6][7][8]. In this case, there is special interest in the possibility of exciting this luminescence through the ligand component of europium β-diketonates, since such excitation does not occur through the system of narrow absorption bands of the Eu 3+ ions but rather through the broad bands of the intraligand π−π * transition or a ligand-metal charge transfer band (LMCT) located in the near UV range (see, for example, [3,[9][10][11]. The problem becomes especially important in cases when the power of the exciting radiation cannot be very high, for example, when designing different kinds of sensor devices based on polymers doped with europium β-diketonates [5,7,8].…”

“…Thus the high thermosensitivity of the "red" photoluminescence in polypropylene films doped with Eu(fod) 3 molecules that we observed in [8] may be used in designing temperature sensors in the 20 o C-80 o C range for medical purposes. In [14], we studied the mechanisms for the photosensitivity of different matrices, including nanoporous glasses, polypropylene, poly(methyl methacrylate) (PMMA), etc., doped with the same molecules, when they are excited into the singlet absorption band and into the ligand-metal charge transfer band. We established two mechanisms for the photoinduced transformation of Eu(fod) 3 molecules when exposed to UV radiation in a polypropylene matrix, which allows us to predict the changes in the intensity of the "red" photoluminescence with exposure time.…”

“…We should point out that all our studies of the spectral properties of polymers and glasses doped with β-diketonates of rare earths and transition metals have been done in samples where the impurity was introduced by soaking them in a solution of supercritical carbon dioxide (SC CO 2 ) [10,15,16]. This doping method has demonstrated its promise and some advantages over other impregnation methods, such as via organic solvents [17].…”

“…Impregnation conditions: temperature in the chamber, 80 o C; pressure, 250 bar; impregnation time, 30 min. The details of the procedure for impregnation of organometallic compounds via a supercritical CO 2 solution were described earlier in [10,15]. The concentration of Eu(fod) 3 molecules in the matrix was determined from the absorption spectra of the samples, from measurement of the intensity of the ligand absorption band with maximum in the 300 nm region, using the procedure in [10].…”