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Fin field-effect transistor (FinFET) scaling beyond the 10-nm node requires formation of a junction isolation region between the source and the drain to suppress sub-fin leakage current. In this paper, heavy species such as Sb and As were implanted at room temperature to form a punch-through stop (PTS) layer in ${n}$ -Ge substrates. The impact of PTS implants on channel doping and defects, as well as junction leakage, was investigated for bulk Ge ${p}$ -FinFET applications. We report retrograde doping profiles with a low surface (channel) dopant concentration of 4–5 $\times 10^{\textsf {16}}$ cm−3 for Sb PTS implants post 550 °C and 650 °C activation anneals. Besides achieving low effective channel doping, the 650 °C high-temperature activation anneal post PTS implant also helps in the reduction of channel defect density. Furthermore, low junction leakage currents are also demonstrated for Sb and As PTS implants with 550 °C and 650 °C activation anneals. To avoid damaging the FinFET channel layer due to PTS ion implantation, Ge homoepitaxy was also studied post Sb PTS implants. However, Sb PTS implants activated at 650 °C without Ge epitaxy exhibit the best results in terms of low channel dopant and defect concentrations, besides junction leakage. [ABSTRACT FROM AUTHOR]

This communication identifies and proposes the generalized templates of directivity expressions for antenna arrays with identical omnidirectional and isotropic elements. Parameters of this expression are the element patterns, interelement distances, and the complex excitation coefficients of all elements. It is further shown that the proposed expression can also satisfactorily calculate the directivity of antenna elements. Examples show the efficiency of the proposed expressions in terms of computational speed, accuracy, and memory requirement. Simpson’s 1/3rd rule is followed for numerical pattern integration. [ABSTRACT FROM PUBLISHER]

In this paper, we discuss continuous time periodic debugging of a software, in which faults are corrected, instead of at the instants of their detection, at some prespecified times. We describe maximum-likelihood estimation for the model parameters assuming exponential distribution for the time between successive occurrence of a fault, which can be used to estimate the reliability of the software. We also derive the asymptotic properties of the estimated model parameters, specially the number of faults initially present in the software. We investigate the finite sample properties of the estimators, specially that of the number of faults, through simulation. Finally, we analyze a dataset obtained from the testing of a flight control software. [ABSTRACT FROM AUTHOR]

The (Nd1–xGdx)2O3 thin films were grown on Si(001) in 2005 using molecular beam epitaxy followed by an in vacuo metallization of Pt contacts. Pt/(Nd1–xGdx)2O3/Si(001) metal-oxide-semiconductor structures have been characterized several times over the period of 2005–2015 in order to investigate the stability of their physical and electrical properties. Core-level X-ray photoelectron spectroscopy (XPS) spectra remeasured during 2015 depict that the layer still retains its original properties that were measured in 2005. Although there has been some degradation of electrical properties such as capacitance and leakage current over several years, interestingly the midgap density of interface traps’ ( $D_{{\mathrm{it}}}) value has been found to be decreased from 1.1 \times 10^12 to 3.5 \times 10^11 eV ^-1 cm ^-2 over the years. The formation of silicate-like interface inferred from XPS measurements can be attributed to such an improvement over this period. Time-dependent dielectric breakdown measurements under constant current stress and constant voltage stress were also carried out to investigate the reliability of the structure. [ABSTRACT FROM PUBLISHER]

A generalized unique expression for directivity of arbitrary planar antenna arrays having \cos ^v\theta , v > - 1 / 2 element pattern is derived. Parameters of the new equation, other than the source type, are operating frequency, location, excitation amplitude and excitation phase of each individual element on that structure. Simplicity and compactness of this equation saves the runtime, memory requirement and computer costs. Examples on three array sets have been given to illustrate the effectiveness of this expression. Result of each example is compared with that of referred work, or a standard numerical method to show the computational efficiency. [ABSTRACT FROM PUBLISHER]