Transistor Models

Transistor Models Skill — Complete PTM Library

Important — do not modify skill files during normal use. When using models, copy the required .lib files into the user's project directory (outside .claude/). Do not modify or delete files inside the skill's assets/models/ directory. Only update the skill's internal files when the user explicitly asks to refresh the model library.

Source: All model files are from PTM — Arizona State University (ptm.asu.edu), free for academic research.

Citations:

• Bulk CMOS nodes: W. Zhao and Y. Cao, "New Generation of Predictive Technology Model for Sub-45 nm Early Design Exploration," IEEE Trans. Electron Devices, vol. 53, no. 11, pp. 2816–2823, Nov. 2006. doi: 10.1109/TED.2006.884077
• PTM-MG FinFET nodes: S. Sinha, G. Yeric, V. Chandra, B. Cline and Y. Cao, "Exploring sub-20nm FinFET design with Predictive Technology Models," DAC 2012, pp. 283–288. doi: 10.1145/2228360.2228414

Directory Structure

assets/models/
├── bulk_cmos/              — Bulk CMOS (BSIM3v3 / BSIM4)
│   ├── ptm180.lib          — 180nm conventional
│   ├── ptm130.lib          — 130nm conventional
│   ├── ptm90.lib           — 90nm conventional
│   ├── ptm65.lib           — 65nm conventional
│   ├── ptm45hp.lib         — 45nm HP
│   ├── ptm45lp.lib         — 45nm LP
│   ├── ptm32hp.lib         — 32nm HP
│   ├── ptm32lp.lib         — 32nm LP
│   ├── ptm22hp.lib         — 22nm HP
│   └── ptm22lp.lib         — 22nm LP
└── finfet/
    ├── models              — PTM-MG library entry point (.LIB ptm{n}hp / ptm{n}lstp)
    ├── param.inc           — Shared parameters (fin_height/fin_width/lg/vdd, per node)
    ├── hp/                 — HP nodes: {7,10,14,16,20}nfet.pm / pfet.pm
    └── lstp/               — LSTP nodes: {7,10,14,16,20}nfet.pm / pfet.pm

Model Reference

Bulk CMOS — Conventional (BSIM3v3/BSIM4, combined NMOS+PMOS)

Bulk CMOS — HP/LP (BSIM4, combined NMOS+PMOS)

FinFET — PTM-MG Multi-Gate (BSIM-CMG)

Entry file: finfet/models — select node and type via .lib section tag:

FinFET model names are nfet / pfet (subckt-wrapped); use NFIN to set the number of fins.

ngspice Usage

Loading a Bulk CMOS File

* Load 45nm HP (contains both nmos and pmos models)
.include "models/bulk_cmos/ptm45hp.lib"

* Instantiate NMOS
M1  drain  gate  source  bulk  nmos  W=1u  L=45n

Loading a PTM-MG FinFET

* Load 7nm HP FinFET
.lib "models/finfet/models" ptm7hp

* PTM-MG model names are nfet / pfet
* Use NFIN (number of fins) instead of W
M1  drain  gate  source  bulk  nfet  NFIN=1  L=7n

Model Type Quick Reference

Key Parameter Quick Reference

Full parameter table in references/model_params.md.

Using a Custom PDK Model

If you have your own .lib file (foundry PDK or measured):

1. Copy it into the project models/ directory.
2. Find the .model name inside the file (e.g. .model mynmos NMOS level=54).
3. Instantiate using that name: M1 d g s b mynmos W=... L=...
4. Configure sweep ranges based on vth0, tox, etc.