The self-consistent response of the electron density of a crystal copper film to an external electrostatic field

2001 ◽  
Vol 43 (3) ◽  
pp. 401-407 ◽  
Author(s):  
G. V. Wolf ◽  
D. V. Fedorov
Keyword(s):  
Electron Density ◽  
Electrostatic Field ◽  
Copper Film ◽  
The Self ◽  
Self Consistent ◽  
Consistent Response

scholarly journals On the Self‐consistent Response of Stellar Systems to Gravitational Shocks

1999 ◽  
Vol 513 (2) ◽  
pp. 626-637 ◽  
Author(s):  
Oleg Y. Gnedin ◽  
Jeremiah P. Ostriker
Keyword(s):  
The Self ◽  
Stellar Systems ◽  
Self Consistent ◽  
Consistent Response

The self-consistent response of stellar disks to bar forcing

1984 ◽  
Vol 276 ◽  
pp. 135 ◽  
Author(s):  
K. O. Thielheim ◽  
H. Wolff
Keyword(s):  
The Self ◽  
Self Consistent ◽  
Consistent Response

Fixed Wand Electronic Flame-Off for Ball Formation in the Wire Bonding Process

1994 ◽  
Vol 116 (3) ◽  
pp. 212-219 ◽  
Author(s):  
Wei Qin ◽  
Ira M. Cohen ◽  
P. S. Ayyaswamy
Keyword(s):  
Electric Field ◽  
Electrostatic Field ◽  
Wire Bonding ◽  
Bonding Process ◽  
The Self ◽  
Wire Length ◽  
Ball Bond ◽  
Self Consistent ◽  
The Wire ◽  
Wire Deflection

In the latest generation of wire bonders, the cycle is so short that the wand electrode is kept stationary and the electronic flame off (EFO) discharge is from the side of the wire. This is the discharge that heats and melts the wire causing roll up into a ball that is pressed down onto the chip to form a ball bond. The balls must be perfectly formed with defects in the few ppm range. In the first part of the paper, the fixed, conically shaped side wand and the improved ring wand design are studied by considering the electrostatic field before the breakdown. In the second part of the paper, discharge development starting from the initial electrostatic field between a wire and a ring wand up to the breakdown, and ionization growth in the gap between the electrodes are both examined by numerical simulations. In the computations, the conservation equations for ions and electrons and Poisson’s equation have been employed for the self-consistent electric field. Based on sensitivity to wire length and wire deflection, the results show that the ring wand is a better design than the conical side wand electrode for ball formation and wire bonding. Also, positive wire polarity is preferred over negative wire polarity.

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