I am drawing the layout of an LNA using 130 nm GF SiGe BiCMOS process in ADS Keysight. However, I have some issues with it.
1. The HBT transistor is composed of 4 terminal, the 4th being the bulk terminal (connection to substrate). In the schematic, it is connected to the "in" terminal of the substrate. However, the 4th terminal is missing on the layout. My LVS therefore has been failing because of the absence of this connection.
How can i connect this on the layout?.
2. My single wire transmission line also has 3 terminal, the third being labelled the "vshield" which must be connected to a pure AC ground. This I was able to connect successfully on the schematic but on the layout, the "vshield" is missing. I have looked at the training material , where it was recommended that the substrate be position at least 80 um aaway from the transmission line. However, my LVS still fails.
1) Your foundry library should have substrate contacts, e.g. called ptap or ntap, which you place in layout close to your transistor. Then LVS should recognize the bulk connection.
2) Should be similar.