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The impact of scaling on the analog performance of MOS devices at RF frequencies was studied. Trends in the RF performance of nominal gate length NMOS devices from 350-nm to 50-nm CMOS technologies are presented. Both experimental data and circuit simulations with an advanced validated compact model (MOS Model 11) have been used to evaluate the RF performance. RF performance metrics such as the cutoff frequency, maximum oscillation frequency, power gain, noise figure, linearity, and 1/f noise were included in the analysis. The focus of the study was on gate and drain bias conditions relevant for RF circuit design. A scaling methodology for RF-CMOS based on limited linearity degradation is proposed.

A thermal neutron image plate (IP) consisting of a mixture of BaFBr : Eu 2+ and Gd2O3 (IP-Gd) is compared with an alternative plate consisting of M 2 B 5 O 9 X : Eu 2+ ( M = Ca , Sr , Ba ; X = Cl,Br ) (IP-B). In particular, the Detective Quantum Efficiency (DQE) of both plates is considered. Monte Carlo simulations of the energy deposition process after the absorption of a neutron show that the variance of the energy deposition in the IP-Gd affects the DQE to a large extent. Because of this, the average number of photoelectrons detected per incident neutron, 〈Nphe〉, has to be only 1.3 for the haloborates to obtain an IP-B with a higher DQE value than the maximum possible with a IP-Gd.

The storage phosphor properties of the compounds M 2 B 5 O 9 X : Eu 2+ ( M = Ca , Sr , Ba ; X = Cl , Br ) have been studied. The best compounds, Sr 2 B 5 O 9 Br : Eu 2+ and Ca 2 B 5 O 9 Br : Eu 2+ , show a photostimulated luminescence yield of, respectively, 21 and 14 photons per incident thermal neutron. They contain natural boron. With these yields, image plates with detective quantum efficiency values of more than 40% are envisaged when using enriched 10B, but the stimulation energy at 633 nm is too high.

Powder samples of the borates YBO 3 : Ce 3+ , GdBO 3 : Ce 3+ , Li 6 Y ( BO 3 ) 3 : Ce 3+ , LaB 3 O 6 : Ce 3+ , GdB 3 O 6 : Ce 3+ , LaMgB 5 O 10 : Ce 3+ , YMgB 5 O 10 : Ce 3+ , CaLaB 7 O 13 : Ce 3+ , CaLaB 7 O 13 : Eu 2+ , Ca 4 YO ( BO 3 ) 3 : Ce 3+ and CaYOBO 3 : Eu 2+ were studied. The photoluminescence properties of Ce3+ in these compounds are discussed and some of them are reported for the first time. The scintillation light yield of the orthoborates YBO 3 : Ce 3+ , GdBO 3 : Ce 3+ , ScBO 3 : Ce 3+ and YAl 3 B 4 O 12 : Ce 3+ is of the order of 10,000 pho/MeV. The light yield due to Ce3+ in the other borates is an order of magnitude lower. In LaB 3 O 6 : Ce 3+ and LaMgB 5 O 10 : Ce 3+ a broad emission band, attributed to self-trapped exciton (STE) emission, is observed under X-ray excitation. The STE light yield of LaB 3 O 6 : Ce 3+ (0.05%) is 8000 pho/MeV and it is quenched at higher Ce concentrations. Thermoluminescence measurements show that none of these materials has a potential to be utilized as a thermal neutron storage phosphor.

In this paper we present the observation that Sr 2 B 5 O 9 Br:Eu 2+ shows thermoluminescence after illumination with UV photons, even when the photon energy is insufficient to induce band to band transitions. The role of the Eu 2+ ions to the trapping process and possible models to explain the observation will be discussed.

We report on the scintillation properties of a LiBaF3 crystal when irradiated with thermal neutrons or gamma rays. This scintillator exhibits cross luminescence and self-trapped-exciton luminescence. The former does not show up under thermal-neutron irradiation, whereas both give a response under gamma irradiation. This offers a unique opportunity for thermal-neutron-gamma discrimination. The effectiveness of the method is demonstrated.

We report on the scintillation properties of a LiBaF3 crystal when irradiated with thermal neutrons or gamma rays. The scintillator exhibits cross luminescence and self-trapped-exciton luminescence. The former does not show up under thermal neutron irradiation, whereas both give a response under gamma irradiation. This offers a unique opportunity for thermal neutron-gamma discrimination. The effectiveness of the method is demonstrated.

We report on the scintillation properties of LiBaF 3 upon irradiation with thermal neutrons. For thermal neutron excitation cross luminescence is not observed, contrary to luminescence under X-ray or γ-ray excitation.

The distortion behaviour of MOSFETs is important for RF-applications. In this paper the influence of technology variations (oxide thickness, substrate doping,...) on distortion is investigated using measurements and a recently developed compact MOSFET model. The influence on distortion of technology scaling down to 0.18 /spl mu/m is verified and further scaling according to the ITRS-roadmap is predicted.

The influence of the gate-oxide thickness, the substrate dope, and the gate bias on the input-referred spectral 1/f noise density Sv/sub gate/ has been experimentally investigated. It is shown that the dependence on the oxide thickness and the gate bias can be described by the model of Hung, and that Sv/sub gate/ can be predicted for future technologies. Discrepancies with the ITRS roadmap are discussed.

The photostimulated luminescence (PSL) and thermoluminescence (TL) properties of a LiYSiO4 : Ce powder sample are reported and discussed. The trapping centers giving rise to PSL are identical to those giving rise to TL and the recombination of detrapped charge carriers takes place on Ce3+.

In this paper a new physical gate leakage model is introduced, which is both accurate and simple. It only uses 5 parameters, making parameter extraction straightforward. As a result the model can be used to extract effective length for modern CMOS technologies. The influence of gate current on the RF performance is studied.