Spherical particles and voids effect on current and potential distribution in integrated circuit leads

摘要

Relationships of resistance with a width of 0.1 mu m for different heights and currents at a given volt drop are plotted for a 0.2 mu m length smooth copper lead. The lead is specified to connect with the integrated circuit AD8622 with its I-sr = 0.350 mA to determine the volt drop = 0.2 mV. The total current is computed according to the total resistance of the lead for the different void radius at this volt drop. The current density value at the right boundary is determined by Ohm's law. After combining the integration of the total current as a prerequisite with the interpolation of current density values from the left, i.e. void edge to the right boundaries, their distribution is obtained, showing current crowding outside of their edges and a great resistance with the increase of their radius. The calculation errors for comparison with the Laplace equation are calculated, mainly located on the corners of void. The potential distribution can be obtained by multiplying sheet resistance to current density distribution. At last, the relationship between resistance, total current, current crowding and calculation errors with the different void radius and lead length are offered in several forms for use in the integrated circuit design.