VUV photo-ionization parameters and effective mean free path of epithermal photoelectrons in pure non-polar dielectric liquids

VUV photo-ionization spectra of cyclohexane, 2,2 dimethylbutane, tetramethylsilane and polydimethylsiloxane oils were experimentally obtained, using a new experimental set-up. Power laws for photocurrent were observed and photoionization thresholds, confirming our previous data, were deduced. Using a 3-parameter adjustment method and Onsager theory, parameters specific of photoionization process were extracted from curves giving the photocurrent as a function of an applied electric field, at photon excess energies between 0.5 eV and 2 eV above the corresponding ionization thresholds. Assuming the range distribution function of thermalized photoelectrons to be a modified exponential function, called PE3, an effective mean free path along the thermalization path in each liquid was deduced from B/sub 3/, the experimental range parameter associated with the range distribution function. These mean free path values, at the epithermal stage, were compared to those of the thermal mean free path of conduction electrons.     

Delay uncertainty in MLGNR interconnects under process induced variations of width,doping, dielectric thickness and mean free path

This paper analyzes the delay performance of multi-layered graphene nanoribbon (MLGNR) interconnect under process induced variations. An equivalent multi-conductor transmission line (MTL) model driven by CMOS gate is employed for the analysis. The propagation delay is analyzed for different interconnect lengths and widths by taking into account the variations in width, dielectric thickness, dielectric constant, interlayer distance and doping concentration of MLGNR. Encouragingly, it is observed that the average deviation in delay is below 3 % for all process induced parameter variations except for the mean free path.     

Nonequilibrium electron distributions and high-field electrontransport in an AlxGa1-xAs-based p-i-nnanostructure semiconductor-a picosecond Raman probe

Electron transport in an Al_xGa_1-xAs (x=0.3) based p-i-n nanostructure semiconductor under the application of an electric field has been studied at T=80 K by picosecond transient Raman spectroscopy. Single-particle excitations associated with spin-density fluctuations were used to directly measure electron distribution functions and drift velocities under various electric field intensities. Extremely nonequilibrium electron distributions were observed. Specifically, for an injected carrier density of n≅1×10¹⁸ cm^-3, a drift velocity V_d as high as 2.5×10⁷ cm/s was measured for an electric field intensity E=18 kV/cm. These experimental results are in good agreement with Ensemble Monte Carlo calculations