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Recently, we developed a disposable acid exposure sensor whose in vitroresponse to acid below pH 4 is linearly determined by the duration of exposure and the degree of acidity. The aim of the present study was to compare the SR to simultaneous esophageal pH and duodenogastroesophageal reflux (DGER) monitoring (Bilitec) in patients investigated for presumed gastroesophageal reflux disease (GERD). Twenty-six patients (16 men, mean age 46 ± 2 years) with symptoms suggestive of GERD underwent 24-hr ambulatory pH monitoring and SR monitoring at 5 cm proximal to the LES. DGER monitoring was performed in 21 patients. Exposure of the esophagus to acid and to DGER were analyzed. These data were compared to SR. A significant correlation was found between the exposure of the distal esophagus to acid and SR (R= 0.85; P< 0.0001). Similarly, the area below a cutoff pH 4 was significantly correlated to SR (r= 0.81; P< 0.0001). SR was not correlated to DGER (r= 0.16; NS). At a cutoff of 50, the sensitivity and specificity of SR to predict esophageal acid exposure >5% of time were 91% and 93%, respectively conclusion, the response of the acid exposure sensor is strongly correlated with the results of simultaneous esophageal pH monitoring. The sensor seems able to reliably predict pathological esophageal acid exposure. These findings warrant larger studies of the clinical potential of the acid exposure sensor in the diagnosis and quantification of GERD.

A thermal anneal technique is proposed to effectively remove electron beam irradiation damage in metal‐nitride‐oxide semiconductor structures. Using a high‐temperature (800–950 °C) H2 anneal treatment the SiO2 layer is impregnated with hydrogen after the nitride deposition. This leads to very low surface state densities for both thick‐oxide and thin‐oxide devices. After irradiation the device is given a mild heat treatment at 450 °C in an inert ambient. A complete removal of the radiation‐induced fixed charges and surfaces states is observed. The effectiveness of the high‐temperature H2 anneal is most pronounced for thin‐oxide MNOS structures. The technique is shown also to be effective in case of other types of ionizing radiation.

The near-surface and bulk behaviour of lattice defects introduced during high temperature processing steps is examined for respectively dry and wet oxidations, oxidations in a chlorine containing atmosphere and inert annealings. The depth and radial distribution of the defects is investigated with optical microscopy and high voltage electron microscopy. The influence of the interstitial oxygen concentration and of the application of a low temperature preannealing is studied in detail. The defect kinetics is discussed in terms of an interstitial growth model.

The gain–bandwidth product fT of a bipolar transistor is calculated, taking the heavy doping effect in the emitter into account. This effect reduces fT, owing to a larger charge storage in the emitter neutral region and a decrease of the built-in voltage of the emitter-base depletion capacitance.

A new calculation method, for the ionisation rates αn, and αp from the ionisation integrals and from γ = αp/αn measurements on diffused junctions, gives new data which, especially for low electric fields, are different from the data of Lee, Logan et al. in value and in slope.

An expression for the tunnelling current between the silicon bands and the traps located in the silicon nitride, in thin-oxide m.n.o.s. memory transistors under low-field conditions, is derived. The theoretical results are compared with available experimental data, and the parameters for the trap distribution are calculated. The agreement with experimental results is satisfactory.

The difference between the calculated and the measured built-in voltage for homo- and heterojunctions is explained by introducing interface states in the vicinity of the metallurgical junction. A general formula is derived for the depletion-layer capacitance of abrupt junctions with interface states.

Experimental results for 1/f noise in m.o.s. transistors with very low surface state densities are presented. A direct relation between noise and surface state density is found, extending previously published data.

It is shown that the use of the space-charge approximation as a trial solution in the computation of potential distributions in semiconductor devices leads to considerable gains in computer time.

This paper presents a screen printing process for the metallization of silicon solar cells. The physics and construction of a classical solar cell are reviewed. The results obtained with a screen printing process are comparable with other, more expensive technologies. This technology does not introduce an additional contact resistance on silicon. The process optimization and the influence of different parameters are discussed.

Thick film conductors based on Al, Cu and Ni have been studied. Because of its high depth of field, a SEM was used to study the microstructures of the fired conductors.

A thick film hybrid transmitter for the radio tracking of wild animals is described. Weight considerations are of prime importance for such transmitters and the system discussed uses thick film hybrid technology, together with a solar cell power supply charging Cd–Ni batteries.

Using a library of available I.C. chips, and a network description of the circuit in terms of these chips, the program CALHYM produces a 100% complete layout of a multilayer hybrid microcircuit in three steps: the partitioning of the logic functions into library chips, the placement of the used chips on the substrate and the routing of the interconnections.