📘 Glossary of Technical Terms — SemiDevKit

This glossary defines key semiconductor, SPICE, TCAD, and physical-design terms
used throughout SemiDevKit.

A

AC Analysis

Small-signal, frequency-domain analysis used to evaluate gain, impedance, and frequency response.

Anneal

A thermal process used to activate dopants, repair lattice damage, or modify material properties.

B

BSIM4

A physics-based MOSFET compact model widely used in SPICE simulators for deep-submicron CMOS technologies
(typically from 130 nm down to ~20 nm nodes).

Butterfly Curve (S–E Curve)

Strain–electric-field relationship observed in ferroelectric or piezoelectric materials.

C

Cgg

Total gate capacitance, defined as:

[ C_{gg} = \frac{\partial Q_g}{\partial V_g} ]

Physically more meaningful than partitioned capacitances (Cgs, Cgd, Cgb).

CV Curve

Capacitance–voltage relationship used to characterize MOS capacitors and MOSFET gate behavior.

Compact Model

A simplified mathematical representation of device I–V and C–V characteristics used in circuit simulation.

D

DIBL (Drain-Induced Barrier Lowering)

Reduction of threshold voltage with increasing drain voltage in short-channel MOSFETs.

DIM (Dimension Sweep)

A sweep of channel length (L) and width (W) used to study short-channel and narrow-width effects.

E

EOT (Equivalent Oxide Thickness)

Effective oxide thickness that represents the capacitance of a high-k gate dielectric in terms of SiO₂.

Extracted Parameters

Device characteristics derived from measurement or simulation, such as Vth, gmmax, Idlin, and Idsat.

F

Ferroelectric

A material exhibiting spontaneous polarization that can be reversed by an applied electric field.

G

gm (Transconductance)

Derivative of drain current with respect to gate voltage:

[ g_m = \frac{\partial I_d}{\partial V_g} ]

The peak value (gmmax) is commonly used for threshold voltage extraction.

H

HCI (Hot-Carrier Injection)

A reliability degradation mechanism in NMOS devices caused by high-energy carriers damaging the gate oxide.

I

Idsat

Drain current in the saturation region at high drain voltage.

Idlin

Drain current in the linear region at low drain voltage.

L

Lateral Electric Field

Electric field along the channel direction; a major contributor to hot-carrier effects.

Layout

Geometric representation of circuit structures used for semiconductor fabrication.

M

Mobility (μ)

Carrier mobility; typically decreases with increasing vertical electric field, scattering, and temperature.

MOSCAP

Metal-Oxide-Semiconductor capacitor, commonly used for CV characterization of gate dielectrics.

N

NBTI (Negative Bias Temperature Instability)

A PMOS reliability degradation mechanism that causes a negative shift in threshold voltage over time.

O

OpenLane

An open-source RTL-to-GDSII digital design flow.
OpenLane-Lite is a reduced, educational variant included in SemiDevKit.

P

Paramus

A physical-parameter-based BSIM4 model-card generator included in SemiDevKit.

Poisson Equation

A fundamental equation governing electrostatic potential inside semiconductor materials;
solved numerically in TCAD modules.

PZT

Lead Zirconate Titanate, a ferroelectric and piezoelectric material widely used in memory and sensor devices.

R

Results Directory

A directory storing generated .csv, .dat, .png, and extracted parameters to ensure reproducibility.

S

SCE (Short-Channel Effects)

Phenomena that degrade MOSFET behavior as channel length is reduced.

SPICE

Simulation Program with Integrated Circuit Emphasis — an industry-standard circuit simulator.

T

TCAD (Technology Computer-Aided Design)

Device-level simulation techniques including Poisson, drift-diffusion, and quantum-corrected models.

Template

A SPICE netlist skeleton used by analyzers to automatically generate simulation cases.

V

Vth (Threshold Voltage)

Gate voltage at which strong inversion forms in a MOSFET.

Vtg / Vtc

Threshold voltages extracted using:

W

Width (W)

MOSFET conduction width; strongly affects drive current and short-channel behavior.

Z

Zr/Ti Ratio

Composition ratio in PZT materials that significantly influences polarization characteristics.

📘 End of Glossary