Automated Design for Micromachining

Suspension, Bistable


A suspension is like a spring, designed to be compliant. However, they are also designed to be stiff in the perpendicular direction. This suspension has two stable resting points.

Layout of a bistable suspension.

Figure 1: Layout of a bistable suspension.


Nothing yet.


Any parameter may be modified, if necessary, to meet design rules. Typically, this involves increasing parameters that specify distances, so that minimum line width and minimum line spacing rules will not be violated. This has been extended to the convention of specifying a zero for some parameters to obtain an instance of the minimum size.

In addition to the parameters listed below, several technology parameters also influence the implementation of parameterized cells. This data must be present in the technology library.

Table 1: Parameters for the 'suspension_bistable' parameterized cell.
Name Description Range Units
layer Control the layer. P1,P2,DT -
length The length of all of the compliant beams. [0,∞) um + +
width The width of the compliant beams. [0,∞) um + +
deflection The deflection of the beams from the center line. The total displacement from one state to the other will be twice this distance. [0,∞) um + +
shuttle_width The width of the shuttle [0,∞) um + +
shuttle_length The length of the shuttle. [0,∞) um + +
anchor width The length of the compliant beams. [0,∞) um + +
include_poly0 If true, a POLY0 ground plane will be included in the cell. The POLY0 ground plane can eliminate most electrostatic attraction between the suspension and the substrate bulk. true/false - + +


[1] Y.-J. Yang, B.-T. Liao, and W.-C. Kuo. "A novel 2x2 MEMS optical switch using the split cross-bar design," Journal of Micromechanics and Microengineering. vol. 17, no. 2, pp. 872-882 (2007).