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Presents a study that proposed a theory for the junction capacitance of mathematically abrupt diodes. Derivation of a general junction capacitance formula; Information on a capacitance formula for an abrupt junction; Evaluation of the general capacitance formula for symmetrical and asymmetrical abrupt junction.

Presents a method of calculating the Raman spectrum from a nonuniformly strained sample. Factors which are taken into account in the calculations; Application of the method to the local oxidation of silicon structures; Details on factors influencing the Raman shift.

Presents a study to calculate the critical thickness and strain relaxation in II-VI strained epilayers, and compare them with experimental values. What commercial semiconductor lasers are based upon; Importance of short-wavelength light emitting diodes; Methodology used to conduct study; Indication of findings; Discussion on results.

Focuses on a study which detailed the calculation of the interaction energy of arrays of dislocations with nonperiodic distribution. Reason for conducting the calculations; Focus of studies on strain relaxation in pseudomorphic epilayers; Situation in which the calculated rate of strain relaxation on annealing the metastable layers at higher temperatures is increased.

The stress field in laterally small strained semiconductor epilayers has been studied by the finite element method. The reaction of the epilayer on the substrate and the bulging-out effect caused by shear forces in the side wall boundaries play an important role. Analytical approximate methods are shown to be deficient. The normal stresses relax faster than a simple exponential with height z and virtually complete relaxation occurs at a height heff≊ [Square_Root]ab/2 (where a and b are the width and length, respectively, of the parallellopipidial epilayer) which is in good agreement with recent experiments. An equivalent lattice spacing fm as a function of z/[Square_Root]ab is defined and calculated. [ABSTRACT FROM AUTHOR]

Background: In vitro studies of a recently developed acid exposure sensor show that the sensor response (SR) to acid < pH 4 is linearly determined by the duration and degree of acidity. The aim was to determine whether SR correlates with the severity of acid-induced esophageal mucosal lesions and acid-induced heartburn. Methods: HCl pH 1.5 or saline was infused into the feline esophagus for 5-20 min. Simultaneously, sensor measurements were performed below the infusion port. The histological damage was scored by an independent pathologist. In 15 normal subjects, HCl pH 1 was infused into the esophagus and the severity of the heartburn (0–5) was scored at 5-min intervals. In 10 subjects who experienced heartburn during acid perfusion, initial perfusion with HCl was repeated during heartburn induction time minus 5 min, followed by perfusion with the subject's own gastric juice, titrated to pH 2; heartburn severity was again scored at 5-min intervals. Acid exposure sensors positioned below the infusion port were removed at heartburn scores 1, 2 and 3. Results: A good correlation was found between SR and the histological score for mucosal damage in the cat esophagus (r = 0.64, P < 0.005). There was a good relation between heartburn severity score and acid exposure time (r = 0.84, P < 0.001), and a significant but weaker relation between heartburn severity and SR. Conclusion: In cats, there is a good relation between the severity of acid-induced esophageal mucosal lesions and SR. In men, there is a significant correlation between the severity of acid-induced heartburn and the simultaneously measured SR. Therefore, SR measurement has the potential of yielding clinically relevant information in the investigation of GERD. [ABSTRACT FROM AUTHOR]