Connectivity Extraction from Substrate and Well Layers

The extractor fully recognizes soft connections to the substrate and well layers.

• The soft connections are established using tap vias. Tap vias can be defined as connections to the substrate or a well layer on which they are placed.
• The substrate and well layers form an area on which you can place devices. The extractor verifies the connections made to the bulk terminal of these devices.
• The extractor evaluates the soft connections to appropriately propagate the connectivity. The extractor supports connectivity extraction of the bulk terminal of a device even when the bulk is not implemented by a physical shape. This is typically the case when an n-type transistor is placed over a p-type substrate and no physical shape represents the bulk area of the transistor for connectivity extraction.
• The extractor allows the substrate and well layers to be partitioned into discrete areas. This enables users to limit the connectivity extraction to a local substrate or a well area created by a partition.

Before these enhancements were implemented, the connectivity of the substrate was not checked at all and any physical shape on a well layer was considered as metal in terms of connectivity propagation. Likewise, the connectivity of shapeless bulk terminals was not checked.

Now, the extractor checks connectivity for the substrate, well layers, and bulk terminals and subsequently creates appropriate open and short markers in the Annotation Browser.

Related Topics

Annotation Browser Assistant

Soft Connection Extraction

Bulk Area Connectivity Extraction

Connectivity Propagation through the Substrate and Well Areas