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The current-voltage characteristics of n-GaN/u-AlGaN/n-GaN heterostructure devices are investigated for potential pressure sensor applications. Model calculations suggest that the current decreases with pressure as a result of the piezoelectric effect, and this effect becomes more significant with thicker AlGaN layers and increasing AlN composition. The change in current with pressure is shown to be highly sensitive to the change in interfacial polarization charge densities. The concept is verified by measuring the current versus voltage characteristics of an n-GaN/u-Al0.2Ga0.8N/n-GaN device under hydrostatic pressure over the range of 0–5 kbars. The measured current is found to decrease approximately linearly with applied pressure in agreement with the model results. A gauge factor, which is defined as the relative change in current divided by the in-plane strain, approaching 500 is extracted from the data, demonstrating the considerable potential of these devices for pressure sensing applications. [ABSTRACT FROM AUTHOR]

Presents a study which examined the Schottky barrier height dependence on the compensation doping in the interfacial silicon layer of aluminum/silicon/n: gallium arsenide Schottky diodes. Experimental method; Analysis; Results and discussion.

Investigates the effects of externally applied uniaxial stress on the device characteristics of semiconductor modulation doped field effect transistors. Shifts in the threshold voltages; Impact of piezoelectric effects; Measurement of the changes in the slopes of the transconductance versus gate-to-source voltage relationships.

Presents a method for the calculation of the deformation profiles in chiral nematic liquid crystal cells. Illustration of the method in cases of an asymmetric twisted nematic cell; Applicability of the method to the study on the stability of ultraviolet type two-domain twisted nematic.

Presents calculations of the effects of external stress on the current-voltage characteristics of double-barrier (001)- and (111)-oriented resonant tunneling devices. Development of the resonant tunneling model; Results; Discussion.

Deals with a study which demonstrated the modification of current-voltage characteristics of double-barrier resonant tunneling devices through internal polarization fields. Background to the study; Sample preparation; Experimental results and discussion.

Presents a study which applied barrier enhancement technique to n-type and p-type gallium[sub0.52]indium[sub0.48]phosphide to determine if a similar modification in the Schottky barrier height can be achieved. Mechanism by which the Schottky barrier is formed and modified; Discussion.

Investigates the uniaxial stress dependence of the properties of the DX center in aluminum compound. Thermal activation energy of the DX center; Details on the experiment; Discussion on the results of the study.

Offers information on a study which examined aluminum/n- and aluminum/p-type Schottky barrier structures grown in situ by molecular-beam epitaxy with thin silicon epitaxial interfacial layers. Theoretical background; Methodology; Results and discussion.

Deals with a study which measured the current-voltage characteristics of gallium arsenide (GaAs)-aluminum arsenide (AlAs)-GaAs-AlAs-GaAs double-barrier heterostructures grown by molecular beam epitaxy on oriented substrates under longitudinal uniaxial stress. Preparation of sample and experimental technique; Current-voltage characteristics of the resonant tunneling diode; Description of the I-V characteristics of the heterostructures.

Presents a theoretical and experimental study of the longitudinal uniaxial stress dependence of I-V characteristics in GaAs-Al[subx]Ga[sub1-x]As-GaAs heterojunction barriers. Procedure to extract parameters for theoretical calculations; Dependence of the I-V characteristics on uniaxial stress in the direction perpendicular to the heterojunction plane; Usefulness of uniaxial stress in elucidating the transport mechanisms in heterojunction barriers.

Examines the transport mechanism of carriers across the Schottky barrier by studying the current-voltage-temperature (I-V-T) characteristics. Procedures for the layer's growth and the processing of diodes; Description of the study of the Schottky barrier height dependence on x; Suggested carrier transport mechanisms.

Presents a study which examined the uniaxial stress dependence of the current-voltage characteristics of n-type aluminum arsenide/gallium arsenide/aluminum arsenide tunnel diodes. Geometry of the samples and method for applying stress; Factor attributed to initial decrease near zero stress; Information on nonresonant current.

Discusses the effect of DX centers on the electrical characteristics of p-n heterojunctions in heterojunction bipolar transistors. Range of voltage over which the capacitance is constant; Transient time of electrons across the depletion region.

Presents a study which investigated the standard gallium [sub0.51]In[0.49]P/GaAs modulation-doped field-effect transistor structure. Description of the metalorganic chemical vapor deposition and chloride vapor phase epitaxy; Fabrication of modulation-doped field-effect transistors; Measurements of current-voltage characteristics.