SiO2 Thickness Calculator
Analyze oxide thickness using process and test inputs. Review capacitance, field, and breakdown estimates easily. Plot trends, export reports, and document fabrication assumptions clearly.
Calculator Input
Use one method at a time. The form stays in one page column.
Example Data Table
| Method | Sample Inputs | Calculated Thickness | Practical Note |
|---|---|---|---|
| Total Capacitance | k = 3.9, Area = 1.2 mm², C = 450 pF | 92.0836 nm | Useful for measured MOS capacitor data. |
| Capacitance Density | k = 3.9, C′ = 42 nF/cm² | 82.2175 nm | Good for normalized device structures. |
| Growth Rate | Rate = 12 nm/min, Time = 8 min | 96.0000 nm | Fast for fabrication planning estimates. |
Formula Used
1) From total capacitance
tox = (ε0 × k × A) / Cox
Use this when measured capacitance and device area are known.
2) From capacitance density
tox = (ε0 × k) / C′ox
Use this when capacitance is already normalized by area.
3) From growth rate and time
tox = Growth Rate × Growth Time
Use this for fast process estimation and planning checks.
Derived values
Electric Field = Applied Voltage / Thickness
Breakdown Voltage = Breakdown Field × Thickness
These outputs help compare operating stress with oxide limits.
How to Use This Calculator
- Select the preferred calculation method.
- Enter the dielectric constant for the oxide stack.
- Fill the method-specific inputs carefully.
- Enter applied voltage and breakdown field values.
- Submit the form to view thickness and derived metrics.
- Review the graph to inspect input sensitivity.
- Download the result table as CSV or PDF.
- Compare outputs with process targets or lab measurements.
Frequently Asked Questions
1. What does this calculator estimate?
It estimates SiO2 thickness from total capacitance, capacitance density, or growth data. It also reports electric field, breakdown voltage, and related oxide values.
2. Which dielectric constant should I use for SiO2?
Thermal silicon dioxide commonly uses a dielectric constant near 3.9. Process conditions may shift effective values slightly in real devices.
3. Why is device area required sometimes?
Total capacitance depends on the active capacitor area. Without area, the tool cannot convert a measured lumped capacitance into oxide thickness.
4. When should I use capacitance density?
Use capacitance density when the capacitance has already been normalized by area. This method is convenient for comparing structures with different sizes.
5. Is the growth method exact?
No. Growth rate methods are planning estimates. Real oxidation can vary with temperature, pressure, chemistry, and surface preparation.
6. What does the electric field output mean?
It shows oxide stress at the chosen applied voltage. Higher fields can increase tunneling risk, leakage, and reliability concerns.
7. Why does thinner oxide increase electric field?
Electric field equals voltage divided by thickness. A thinner oxide under the same voltage experiences a larger internal field.
8. Can I use this for other dielectrics?
Yes, for first-pass estimates. Replace the dielectric constant with the material value, then verify against measured process data.