Numerical study on current and thermal distributions of electrical contacts by FEM

Numerical stress analysis while joining an electrical contact comprising of copper wire and copper sheet using ultrasonic metal welding process is vital in many of the automotive applications. During ultrasonic metal welding, shear and normal force act at the interface between the welded specimens. These forces are the result of ultrasonic vibrations transmitted by Sonotrode onto the welded specimens. In this work, the distribution of the stress developed at the interface and the correlation of the developed stress with strength of joint are studied. The theoretical stress values are determined using various levels of ultrasonic metal welding process parameters such as clamping force, vibration amplitude and weld time to validate the results of stress obtained from finite element analysis. The results of stress from numerical analysis are found to be in good agreement with that of results obtained from the theoretical calculations.

Download Full-text

Numerical study of electric diffusion effect due to imperfect electrical contacts

IEEE Transactions on Magnetics ◽

10.1109/20.706511 ◽

1998 ◽

Vol 34 (4) ◽

pp. 1249-1251 ◽

Cited By ~ 1

Author(s):

Bok-Ki Kim ◽

Kuo-Ta Hsieh

Keyword(s):

Numerical Study ◽

Electrical Contacts ◽

Diffusion Effect

Download Full-text

TEM characterization of Au/Polysilicon interactions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176381 ◽

1990 ◽

Vol 48 (4) ◽

pp. 650-651

Author(s):

N. David Theodore ◽

Leslie H. Allen ◽

C. Barry Carter ◽

James W. Mayer

Keyword(s):

Solid Phase ◽

Single Crystal Silicon ◽

Chemical Vapor ◽

Electrical Contacts ◽

Silicon Substrates ◽

Crystal Silicon ◽

Transmission Electron ◽

Polysilicon Films ◽

The Stability

Metal/polysilicon investigations contribute to an understanding of issues relevant to the stability of electrical contacts in semiconductor devices. These investigations also contribute to an understanding of Si lateral solid-phase epitactic growth. Metals such as Au, Al and Ag form eutectics with Si. reactions in these metal/polysilicon systems lead to the formation of large-grain silicon. Of these systems, the Al/polysilicon system has been most extensively studied. In this study, the behavior upon thermal annealing of Au/polysilicon bilayers is investigated using cross-section transmission electron microscopy (XTEM). The unique feature of this system is that silicon grain-growth occurs at particularly low temperatures ∽300°C).Gold/polysilicon bilayers were fabricated on thermally oxidized single-crystal silicon substrates. Lowpressure chemical vapor deposition (LPCVD) at 620°C was used to obtain 100 to 400 nm polysilicon films. The surface of the polysilicon was cleaned with a buffered hydrofluoric acid solution. Gold was then thermally evaporated onto the samples.

Download Full-text