In this study, conductive silver features using inkjet printing have been successfully prepared and their sintering studied.
Regarding conductivity, metallic inks are the most efficient available conductive inks, even if important drawbacks regarding
the use of such inks in inkjet still exist. Indeed, the sintering step is an important limiting factor for the productivity
and the substrate choice. An infrared (IR) drying method was experimented to optimize the sintering treatment time. Trials
with glass and paper substrates were performed and proved that IR drying is interesting to optimize sintering. Indeed a similar
level of resistance was obtained for conventional heating (200 °C, 5 min) and for IR radiations within a shorter treatment
time (3 min). Moreover, the substrate temperature during the IR sintering treatment was controlled. The substrate appears
to be a relevant parameter to optimize sintering because its thermal behaviour directly impacts on the treatment duration.
And for the first time a sheet resistance of 1.9 Ω sq−1 was obtained on paper substrate after only 2 min of IR treatment without any observation of substrate degradation. The evaluation
of an electrical treatment on the sintering of a nanoparticle film was also performed using a corona pre-treatment. This lead
appears to be interesting because the study proves that an electrical treatment can initiate the sintering of silver nanoparticles.
The current flow generated by the corona electrodes certainly generates a local heating by dissipation of the conductive pattern.
Finally, the solutions presented in this article allow reducing the sintering time of silver conductive inkjet inks. However
mainly, it proves that using paper as substrate for such inks is now possible. 相似文献
We compare the results of small angle neutron scattering on the flux line lattice (FLL) obtained in the borocarbide superconductor
LuNi2B2C with the applied field along the c- and a-axes. For H‖c the temperature dependence of the FLL structural phase transition from square to hexagonal symmetry was investigated. Above
10 K the transition onset field. H2(T), rises sharply, bending away from Hc2(T) in contradiction to theoretical predictions of the two merging. For H‖a a first order FLL reorientation transition is observed at Htr=3–3.5 kOe. Below Htr the FLL nearest neighbor direction is parallel to the b-axis, and above Htr to the c-axis. This transition cannot be explained using nonlocal corrections to the London model. 相似文献
Computable lower and upper bounds for the symmetric elliptic integrals and for Legendre's incomplete integral of the first kind are obtained. New bounds are sharper than those known earlier. Several inequalities involving integrals under discussion are derived. 相似文献
Near‐field optical microscopy techniques provide information on the amplitude and phase of local fields in samples of interest in nanooptics. However, the information on the near field is typically obtained by converting it into propagating far fields where the signal is detected. This is the case, for instance, in polarization‐resolved scattering‐type scanning near‐field optical microscopy (s‐SNOM), where a sharp dielectric tip scatters the local near field off the antenna to the far field. Up to now, basic models have interpreted S‐ and P‐polarized maps obtained in s‐SNOM as directly proportional to the in‐plane ( or ) and out‐of‐plane () near‐field components of the antenna, respectively, at the position of the probing tip. Here, a novel model that includes the multiple‐scattering process of the probing tip and the nanoantenna is developed, with use of the reciprocity theorem of electromagnetism. This novel theoretical framework provides new insights into the interpretation of s‐SNOM near‐field maps: the model reveals that the fields detected by polarization‐resolved interferometric s‐SNOM do not correlate with a single component of the local near field, but rather with a complex combination of the different local near‐field components at each point (, and ). Furthermore, depending on the detection scheme (S‐ or P‐polarization), a different scaling of the scattered fields as a function of the local near‐field enhancement is obtained. The theoretical findings are corroborated by s‐SNOM experiments which map the near field of linear and gap plasmonic antennas. This new interpretation of nanoantenna s‐SNOM maps as a complex‐valued combination of vectorial local near fields is crucial to correctly understand scattering‐type near‐field microscopy measurements as well as to interpret the signals obtained in field‐enhanced spectroscopy.
The theory of motional narrowing of spectral lines is reconsidered from the standpoint of coherence time of the radiation signal. It is found that, if an oscillator undergoes Markovian frequency modulation due to interaction with a thermal bath, then the linewidth of its power spectrum is inversely proportional to the thermal relaxation rate of the bath state for rapid enough relaxation. Classic Dicke narrowing and the orientational broadening of Rayleigh and Raman lineshapes are shown to be instances of this sort of behavior. 相似文献
In orthogonal polynomial compression, the short-term speech spectrum is first approximated by a family of orthogonal polynomials. The coefficients of each polynomial, which vary over time, are then adjusted in terms of their average value and range of variation. These adjustments can be used to compress (or expand) temporal variations in the average level, slope, and various forms of curvature of the short-term speech spectrum. The analysis and reconstruction of the short-term speech spectrum using orthogonal polynomials was implemented using a digital master hearing aid. This method of compression was evaluated on eight sensorineurally hearing-impaired listeners. Speech recognition scores were obtained for a range of compression conditions and input levels with and without frequency shaping. The results showed significant advantages over conventional linear amplification when temporal variations in the average level of the short-term spectrum were compressed, a result comparable to that obtained with conventional amplitude compression. A subset of the subjects showed further improvement when temporal variations in spectrum slope were compressed, but these subjects also showed similar improvements when frequency shaping was combined with level-only compression. None of the subjects showed improved speech recognition scores when variations in quadratic curvature were compressed in addition to level and slope compression. 相似文献