Analyze oxide thickness using capacitance, area, and permittivity. Compare process assumptions with fast calculated outputs. Download reports, inspect formulas, and visualize thickness relationships instantly.
This graph varies capacitance around the entered value while keeping gate area and dielectric constant fixed.
| Case | Capacitance (pF) | Area (µm²) | k | Calculated Thickness (nm) | Gate Voltage (V) |
|---|---|---|---|---|---|
| Sample A | 3.8 | 1000 | 3.9 | 9.08 | 1.8 |
| Sample B | 5.5 | 1200 | 3.9 | 7.53 | 1.2 |
| Sample C | 2.4 | 800 | 7.5 | 22.14 | 2.0 |
| Sample D | 1.9 | 450 | 3.9 | 8.18 | 1.0 |
Gate oxide thickness is a critical parameter in MOS design. It links process control, capacitance behavior, electric field strength, and device scaling. Engineers often estimate oxide thickness from measured capacitance and known gate area when reviewing fabrication results or validating a design assumption.
This calculator uses the basic capacitor model for a dielectric layer. It converts your capacitance input from pF to farads and your gate area from square micrometers to square meters. Then it applies the dielectric relation to estimate the oxide thickness. This is helpful during device characterization, lab reporting, and fast screening work.
The tool also returns equivalent oxide thickness, capacitance density, and oxide electric field. Those outputs help compare different dielectric materials and assess whether a measured structure aligns with a target process value. The tolerance window is useful when you need a quick pass or fail style review.
The included graph shows how thickness changes as capacitance shifts around the measured point. Since thickness is inversely proportional to capacitance, even small capacitance changes can alter the estimated dielectric thickness. Use the example table for reference before entering your own numbers.
Main relation: Cox = (ε0 × k × A) / tox
Rearranged for thickness: tox = (ε0 × k × A) / Cox
Capacitance density: C/A
Equivalent oxide thickness: EOT = tox × (3.9 / k)
Electric field: E = Vg / tox
Where: ε0 = 8.854187817 × 10-12 F/m, k is the relative dielectric constant, A is gate area, and Cox is measured gate capacitance.
It is the insulating layer thickness between the gate and channel. It strongly affects capacitance, field strength, leakage behavior, and device control in MOS structures.
A gate oxide behaves like a capacitor dielectric. If capacitance, area, and dielectric constant are known, thickness can be estimated directly from the capacitor equation.
Use square micrometers in this calculator. The script converts that input to square meters before applying the thickness formula.
Equivalent oxide thickness compares another dielectric to silicon dioxide. It shows the SiO2 thickness that would provide the same capacitance performance.
Thickness and capacitance are inversely related in the dielectric equation. If area and dielectric constant stay fixed, a higher capacitance implies a thinner oxide layer.
It compares the calculated thickness against your target value and the allowed percentage band. This gives a quick screening result for process acceptance.
Yes. Enter the correct relative dielectric constant for the material. The tool will then estimate physical thickness and also show equivalent oxide thickness.
It is best for estimation, review, and early engineering checks. Final signoff should also use detailed process data, measurement conditions, and device-specific validation.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.