Introduction
A thermal-in-plane actuator, also known as a bent-beam actuator, uses electro-thermal effects to heat a bent-beam. To account for the beams expansion, the beam buckles. The buckling motion can be used for actuation.
Another electro-thermal library actuator, the Guckel actuator, is also available in the library as the heatuator parameterized library.
Figure 1: Layout for tipuator with two beams and a beam length of 200um.
Figure 2: Layout for tipuator with two beams, a beam length of 200um, and a POLY0 ground plane.
Figure 3: Layout for tipuator with a single beam and a beam length of 200um.
Theory
Please refer to the theory section in the documentation for the heatuator parameterized cell.
Parameters
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.
| Name | Description | Range | Units | ||
|---|---|---|---|---|---|
| length | The distance between the beam's anchors. | [0,∞) | um | ||
| angle | The angle, in radians, between the a parallel line connecting the beam's anchors and the beam itself. | [0,π/4) | um | ||
| count | One of the main advantages of tipuators is that the beams can be easily ganged. This parameter controls the number of beams in the actuator. | [1,∞) | - | ||
| width | The width of the bent-beams. If less than the minimum spacing, the beam width will be automatically increased. | [0,∞) | um | ||
| spacing | The space between the bent-beams, if more than one beam is present. If less than the minimum spacing, the beam spacing will be automatically increased. | [0,∞) | um | ||
| shuttle_width | The width of the shuttle, which is the central portion connecting the beams. If less than the nominal spacing, the shuttle width will be automatically increased. If dimples are present, then the shuttle width may be increased further to include minimum enclosure rules for the dimples. | [0,∞) | um | ||
| pin_size | This size of the actuator's terminals. Please refer to the documentation for the pin parameterized cell. The pin's size may be increased, if necessary, to provide attachments points for the beams. | [0,∞) | um | ||
| pin_chamfer | This is the length along each corner that will be chopped off the terminals. Typically this value should be zero, but may be used to reduce spurious DRC violations with non-manhattan geometries. | [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 actuation and the substrate bulk. | true/false | - | + | + |
