THICK_ACTIVE is a layer used for those processes offering two different thicknesses of gate oxide (typically for the layout of transistors that operate at two different voltage levels). The ACTIVE layer is used to delineate all the active areas, regardless of gate oxide thickness. THICK_ACTIVE is used to mark those ACTIVE areas that will have the thicker gate oxide; ACTIVE areas outside THICK_ACTIVE will have the thinner gate oxide. THICK_ACTIVE by itself (not covering any ACTIVE polygon) is meaningless.
| Rule | Description | Lambda | ||
|---|---|---|---|---|
| SCMOS | SUBM | DEEP | ||
| 24.1 | Minimum width | 4 | 4 | 4 |
| 24.2 | Minimum spacing | 4 | 4 | 4 |
| 24.3 | Minimum ACTIVE overlap | 4 | 4 | 4 |
| 24.4 | Minimum space to external ACTIVE | 4 | 4 | 4 |
| 24.5 | Minimum poly width in a THICK_ACTIVE gate | 3 | 3 | 3 |
| 24.6 | Every ACTIVE region is either entirely inside THICK_ACTIVE or entirely outside THICK_ACTIVE | |||