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Hot-carrier-induced photoemission of subquarter-micron n-MOSFETs is analyzed using a specially designed test structure, which has a wide channel width of 2.0 mm for sufficient photoemission intensity. Since the test structure consists of parallel-connected unit MOSFETs and photoemission images are uniform, it can be estimated that measured spectra are the same as those from unit MOSFETs. The relation between photon counts and photon energy suggests that photon energy has a Boltzman distribution; exp(-hv/k[T.sub.e]). The electron temperature [T.sub.e] calculated from photon emission spectrum takes minimum value at the channel length of 0.23 [micro]m. If [T.sub.e] is related to the device reliability, it suggests the possibility that the device structure optimized for a certain channel length may not be optimum for other channel length devices. Index Terms--Hot carriers, MOSFETs, photoemission, spectral analysis.

A method based on calorimetry and an instrument are described for the absolute measurement of the energy contained in optical radiation, especially in the optical signatures of electrostatic discharge. The optical emission of a spark gap, comprised of two stainless-steel spheres, was collected by an optical condenser system and focused on the calorimeter sensor. The system was calibrated using a set of light-emitting diodes and tested using either single-pulse discharge or a continuously operating optical source. The calorimeter system detectivity, in terms of output voltage related to the input energy, was determined to be 4.3 x [10.sup.7] V*[J.sup.-1] and its detection limit was 2.3 x [10.sup.-13] J. The system has application for nonintrusive characterization of optical emissions associated with discharge events. Index Terms--Calorimetric, electrostatic discharge, measurements, optical signals.

This article describes the design and construction of an experimental setup for simultaneously monitoring kinetics of the fluorescence yield and delayed light emission. Data show that the equipment is useful to study photosystem II reaction kinetics involving pigment 680 and the accompanying redox states in photosynthesis.

Optical microcavities allow control over the interaction between light and matter, thus making them an important testing ground for basic optical physics. This review focuses on two of these interactions, spontaneous emission and energy transfer. Emphasis is placed on the underlying concepts, which are presented in the context of recent developments. Practical application of the microcavity concept to devices is now well underway and a discussion of these aspects forms an integral part of the review. This field is far from mature and though much has been accomplished, many questions in this area remain, some of which are identified and discussed.

Electron emission measurements were conducted on laser ablated and laser annealed 100-nm-thick, carbon-doped BN film prepared on polycrystalline diamond at pressures of 1x10(super-8) Torr and at room temperature. Current voltage characteristics were consistent with the classical Fowler-Nordheim behavior at low currents. Deviations correlated to nonlinear BN film resistance were observed at high currents.

To study the effects of scintillator light yield nonproportionality, a technique has been developed to calculate photon response. A discrete convolution of measured electron response and the electron energy distribution for a particular scintillator yields the photon response. By establishing the ability to accurately calculate photon response, the experimental implications of scintillator light yield nonproportionality and geometry effects can be studied without the requirement for experimental measurements. This technique also provides a more detailed characterization of photon response than experimental techniques that rely on the use of multiple gamma-ray and X-ray sources. To demonstrate this technique, NaI(Tl), Ca[F.sub.2](Eu), and LSO(Ce) photon responses have been calculated. By comparing calculated results to both measured photon responses and previously published photon responses for these scintillators, this technique has been validated.

The modeling of CuInSe2-based heterojunctions in thin films on the basis of surface analysis experiments is discussed. Experiments involve the in situ photoemission measurements of CuInSe2, the evaporation of an ohmic metal contact onto the surface n-type layer and the measurement of spectral quantum efficiency electron-beam-induced current. The existence of the chalcopyrite/ defect chalcopyrite heterojunction was proven.

Research demonstrates measuring charge-transfer characteristics of the emission properties of the excited states of bipyridine complexes using transient direct current photoconductivity technique.

Photoemission spectroscopic studies of equilibrium segregation at GeSi surfaces confirm the segregation of Ge in the first atomic layer of Ge0.5Si0. 5(100)2 times 1 and Si in the second layer. A comparative study of resolved signals from the dimer atoms of the reconstructed (100)2 times 1 surfaces of Ge, Si and equiatomic Ge-Si alloy reveals the significant aggregation of Ge on the surface layer of the alloy and that Si atoms are dominant in the second layer. Photoemission spectroscopic data agree with theoretical predictions.

A p-InP:n-amorphous hydrogenated silicon (ASIL) heterojunction is fabricated and analyzed for its electrical and photoelectrial properties. Current-voltage curves plotted for an InP-ASIL junction reveal good forward to reverse current ratios. The capacitance per unit area for the device is measured at a frequency of one megahertz and diode quality factors range from 1.9 to 2.6. Internal photoemission methods generate band offsets and junction current is measured as an incident light energy function for various biases.

The issue of finding a new electromagnetic interference (EMI) measurement detector with proper weighting properties for the effect of disturbances on digital communication services is of great importance for the development of future emission standards. In this paper, we investigate the root-mean-square (rms) detector as a possible candidate for future emission measurements. This investigation is done for type of disturbances typical for information technology (IT) equipment, i.e., a repetitive pulse waveform. In this paper, we show that the tolerated rms value of the disturbance level related to a certain bit-error probability is in practice independent of the pulse width of a repetitive pulsed disturbance signal. Furthermore, the variation of this tolerated rms value with the pulse-repetition frequency of the disturbance can easily be modeled. These properties make it possible to express the maximum allowed disturbance level in terms of the output from the rms detector. The conclusion is that the rms detector is a promising candidate for future emission standards where the disturbance effect on digital communication services is considered.

The electronic structure of strained and unstrained Gd(0001) has been studied with spin-polarized photoemission spectroscopy and spin-polarized inverse photoemission spectroscopy. In this work, we observed that relaxation of the expansively strained in-plane crystal lattice constant, of Gd(0001) on Mo(112), significantly diminishes the differences in the electronic structure from that observed for Gd(0001) grown on W(110). The defects that are incorporated in the Gd films, with increasing film thickness, lead to an in-plane lattice relaxation. Such thickness dependent strain relief results a loss of net polarization for Gd(0001) grown on Mo(112) compared to the relatively unstrained Gd(0001) films grown on W(110). Index Terms--Rare earth magnetism, spin-polarized inverse photoemission, magneto-striction, strain relief and misfit dislocations.

The quest for faster and faster time-resolved measurements has reached a new level: Cavalieri et al. report (page 1029 of this issue) (1) that they have measured a delay of [...]