Welcome to nanohub-padre’s documentation!

nanohub-padre is a Python library for creating and running PADRE semiconductor device simulations on nanoHUB or locally. It provides a Pythonic interface to generate PADRE input decks and visualize simulation results — no manual file parsing required.

PADRE (Physics-based Accurate Device Resolution and Evaluation) is a 2D device simulator that solves the drift-diffusion equations for semiconductor devices.

Features

  • One-line device creation — factory functions for PN diode, MOS capacitor, MOSFET, MESFET, BJT, Schottky diode, and solar cell

  • Built-in visualization — plot_band_diagram(), plot_iv(), plot_cv(), plot_electrostatics(), plot_carriers(), plot_transfer(), plot_output(), plot_gummel(), plot_contour()

  • Automatic output management — outputs are registered and parsed automatically after sim.run(); no manual file handling

  • Rappture-compatible decks — generated input decks match the nanoHUB Rappture tool reference decks (keyword order, interface cards, permi=, etc.)

  • Jupyter notebooks — six ready-to-run example notebooks covering all major device types

Quick Start

MOS Capacitor C-V Analysis

from nanohubpadre import create_mos_capacitor

sim = create_mos_capacitor(
    oxide_thickness=0.005,       # 5 nm SiO2
    silicon_thickness=0.05,
    substrate_doping=1e17,
    substrate_type="p",
    gate_type="n_poly",
    log_cv=True,
    log_bands_eq=True,
    vg_sweep=(-2.0, 2.0, 0.05),
    ac_frequency=1e6,
)

result = sim.run()
if result.returncode != 0:
    raise RuntimeError(f"Simulation failed:\n{result.stderr}")

sim.plot_band_diagram(suffix="eq", title="Band Diagram at Equilibrium")
sim.plot_cv(title="MOS Capacitor C-V")

MOSFET Transfer Characteristic

from nanohubpadre import create_mosfet

sim = create_mosfet(channel_length=0.025, device_type="nmos")

result = sim.run()
if result.returncode != 0:
    raise RuntimeError(f"Simulation failed:\n{result.stderr}")

sim.plot_transfer(gate_electrode=3, drain_electrode=2)

Building from Scratch

from nanohubpadre import (
    Simulation, Mesh, Region, Electrode, Doping,
    Contact, Material, Interface, Models, System, Solve, Log
)

sim = Simulation(title="PN Diode")

sim.mesh = Mesh(nx=100, ny=3)
sim.mesh.add_x_mesh(1, 0.0)
sim.mesh.add_x_mesh(50, 0.5, ratio=0.8)
sim.mesh.add_x_mesh(100, 1.0)
sim.mesh.add_y_mesh(1, 0.0)
sim.mesh.add_y_mesh(3, 1.0)

sim.add_region(Region(1, ix_low=1, ix_high=100, iy_low=1, iy_high=3,
                      material="silicon", semiconductor=True))
sim.add_electrode(Electrode(1, ix_low=1,   ix_high=1,   iy_low=1, iy_high=3))
sim.add_electrode(Electrode(2, ix_low=100, ix_high=100, iy_low=1, iy_high=3))

sim.add_doping(Doping(p_type=True, concentration=1e17, uniform=True, x_right=0.5))
sim.add_doping(Doping(n_type=True, concentration=1e17, uniform=True, x_left=0.5))

sim.add_contact(Contact(all_contacts=True, neutral=True))
sim.add_material(Material(name="silicon", taun0=1e-6, taup0=1e-6))
sim.models = Models(temperature=300, srh=True, conmob=True, fldmob=True,
                    print_models=True)
sim.system = System(electrons=True, holes=True, newton=True)

sim.add_solve(Solve(initial=True))
sim.add_log(Log(ivfile="iv"))
sim.add_solve(Solve(project=True, v1=0.0, vstep=0.05, nsteps=20, electrode=1))

result = sim.run()
if result.returncode != 0:
    raise RuntimeError(f"Simulation failed:\n{result.stderr}")

sim.plot_iv(title="PN Diode Forward I-V")

Installation

pip install nanohub-padre

Or from source:

git clone https://github.com/nanohub/nanohub-padre.git
cd nanohub-padre
pip install -e .

Contents:

Indices and tables