The general form of
the relations between the vertical displacement W and a concentrated load P
on the surface plane of the pad is expressed as (1)
...(1)
For single pad with asperity, we use Equation (2)
and (3) which has the same form as Yukawa Potential.
...(2)
...(3)
Equation (2) and (3) will be (4) and
(5) using Boussinesq's Solution when we can assume elastic half-space.
...(4)
...(5)
For stack pad, we have to take into
account the bending of upper layer pad.
...(6)
For Stacked Pad, we use Equation below.
...(7)
We recommend to use CMPPadMode "2" usually for simulations because of the
physical adequacy.
Fig. 1. Model Image for Single Layer Pad with Asperity
Fig. 2. Model Image for Stack Layer Pad with Asperity
