Field analysis of a circular thin-film/foil resistor

The general theory of Brillouin scattering out of the guided optical modes by the acoustic modes of a thin film optical waveguide is formulated in terms of a total field analysis which includes the effects of both the elastooptic and corrugation scattering mechanisms. The general analytical forms for the field discontinuities at the film boundaries are given and the spectral densities are evaluated for two particular radiative geometries. The results of numerical calculations for the geometries are presented.

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Harmonic Analysis of AlN Piezoelectric Mesa Structures

MRS Proceedings ◽

10.1557/proc-1129-v11-08 ◽

2008 ◽

Vol 1129 ◽

Author(s):

Madhulika Mazumdar ◽

A. Kabulski ◽

R. Farrell ◽

Sridhar Kuchibhatla ◽

V. R. Pagán ◽

...

Keyword(s):

Thin Film ◽

Electrical Circuit ◽

Field Analysis ◽

Element Analysis ◽

Fem Method ◽

In Series ◽

Electrical Loads ◽

Piezoelectric Structures ◽

Fast Rise ◽

Rc Time Constant

AbstractIn this work we report the displacement response of piezoelectric Aluminum Nitride (AlN) thin film MESA in an electrical circuit consisting of a circular MESA in series with a resistance subjected to time varying electrical loads. ANSYS was utilized for the simulation of 3D piezoelectric structures; using coupled field analysis to understand the electro-mechanical behavior of AlN thin film mesas. ANSYS applies finite element analysis (FEM) method to simulate the transient piezoelectric trends. Ringing and overshoot effects were observed in the thin simulation results on applying pulse voltages of varying frequencies to the circuit. The fast rise time of the voltage pulse could be exciting these effects. The effect of fast rising pulse voltages on the RC time constant of the circuit is still unclear at this point and needs to be further investigated.

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Thin film write head field analysis using a benchmark problem

IEEE Transactions on Magnetics ◽

10.1109/20.877789 ◽

2000 ◽

Vol 36 (4) ◽

pp. 1784-1787 ◽

Cited By ~ 5

Author(s):

K. Fujiwara ◽

F. Ikeda ◽

A. Kameari ◽

Y. Kanai ◽

K. Nakamura ◽

...

Keyword(s):

Thin Film ◽

Field Analysis ◽

Benchmark Problem

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Luminescence Properties of Thin-Film SrS:Cu Phosphors for Electroluminescent Displays

MRS Proceedings ◽

10.1557/proc-508-281 ◽

1998 ◽

Vol 508 ◽

Cited By ~ 5

Author(s):

T.C. Jones ◽

W. Park ◽

E. Mohammed ◽

B.K. Wagner ◽

C.J. Summers ◽

...

Keyword(s):

Thin Film ◽

Fine Structure ◽

Peak Shift ◽

Peak Position ◽

Teller Effect ◽

Field Analysis ◽

Excitation Wavelength ◽

Jahn Teller ◽

Jahn Teller Effect ◽

Rigorous Treatment

AbstractThe origin of the electronic fine structure in thin-film SrS:Cu has been interpreted in terms of the several possible perturbations including spin-obit coupling, the Jahn-Teller effect and low symmetry splittings. Photoluminescence excitation measurements showed that the peak position of the excitation bands were independent of temperature suggesting that the electronic fine structure in our system was not due to the Jahn-Teller effect. Selective excitation measurements revealed that no peak shift occurs with changing excitation wavelength, indicating that Cu+ pairs or aggregates and Cu+-defect coupled centers were not existent in our system. Finally, several models were proposed for off-center displacements of Cu in SrS, since a rigorous treatment of these displacements is difficult. Both the tetragonal and trigonal distortion models for a <111> displacement yielded reasonable distortions parameters of 0. 16Å and 0.11Å, respectively. However, crystal field analysis showed that a <110> displacement was more likely since the energy level splitting scheme more closely resembled the observed data.

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An Investigation of Thin-Film Coating/Substrate Systems by Nanoindentation

Journal of Engineering Materials and Technology ◽

10.1115/1.2807005 ◽

1998 ◽

Vol 120 (2) ◽

pp. 154-162 ◽

Cited By ~ 7

Author(s):

Jackie Li ◽

Erik T. Thostenson ◽

Tsu-Wei Chou ◽

Laura Riester

Keyword(s):

Thin Film ◽

Indentation Load ◽

Field Analysis ◽

Hard Coating ◽

Hard Substrate ◽

Contact Radius ◽

Soft Substrate ◽

Dlc Coating ◽

Material Systems ◽

Load Displacement

The indentation load-displacement behavior of three material systems tested with a Berkovich indenter has been examined. The materials studied were the substrate materials—silicon and polycarbonate, and the coating/substrate systems—diamond-like carbon (DLC) coating on silicon, and DLC coating on polycarbonate. They represent three material systems, namely, bulk, soft-coating on hard-substrate, and hard-coating on soft-substrate. Delaminations in the soft-coating/hard-substrate (DLC/Si) system and cracking in the hard-coating/soft-substrate system (DLC/Polycarbonate) were observed. Parallel to the experimental work, an elastic analytical effort has been made to examine the influence of the film thickness and the properties of the coating/substrate systems. Comparisons between the experimental data and analytical solutions of the load-displacement curves during unloading show good agreement. The analytical solution also suggests that the Young’s modulus and hardness of the thin film can not be measured accurately using Sneddon’s solution for bulk materials when the thickness of the film is comparable to the loading contact radius of the indenter. The elastic stress field analysis provides a basis for understanding the experimentally observed delaminations and cracking of the coating/substrate systems.

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