Hints, Tips and Solutions
Q. How can I use the SOI BSIM3_MG routine to extract inital SOI SPICE model parameters.
A. The BSIM3_MG routine in SOI module of UTMOST III can be used to extract SOI model parameters. The SOI BSIM3_MG routine operation is similar to the one in MOS module. However the “Measurement Variables” (Figure 1) and biasing of the SOI device is unique.
The SOI devices can have 4 or 5 terminals. For 4 terminal SOI devices typically the bulk node floats and drain, gate, source and backgate terminals are used for biasing. For 5 terminal SOI devices the bulk terminal has a contact too. The number of terminals for the SOI devices can be defined by toggling the “# of Terminals” button in the system screen.
In order to support the combinations of 4 or 5 terminal devices the measurement setup screen of SOI BSIM3_MG routine had to be redesigned. The SOI BSIM3_MG routine can handle stepping of bulk bias while the backgate bias is constant or stepping of backgate bias while bulk bias is constant.
