Etch Rate Calculator
Divide the removed thickness (initial film thickness minus final film thickness) by the etch time to get the average etch rate.
Description
Calculate average semiconductor etch rate in nanometers per minute from removed film thickness and etch time.
Etch rate converts a measured thickness loss over a timed process interval into an average removal rate. It is useful for comparing process runs and estimating a first-pass etch time when the rate is reasonably stable.
When to use Etch Rate Calculator
- Convert profilometer or ellipsometer thickness loss into nm/min
- Compare average removal rates across recipes or process windows
- Estimate duration for a similar target thickness after a rate has been characterized
How the calculation works
The calculator divides removed thickness by elapsed etch time. Removed thickness means initial film thickness minus final film thickness, so an unchanged film produces zero average rate.
average etch rate = removed thickness / etch time Interpreting the result
The result is an interval average. Endpoint thickness measurements cannot reveal ignition delay, loading effects, endpoint overshoot, or a rate that changes during the run.
Assumptions and limitations
- Etch time must be positive; removed thickness may be zero but not negative.
- Inputs must describe the same location or a clearly defined wafer average.
- Do not extrapolate a characterized average rate across different materials, plasma conditions, chamber states, or feature geometries without validation.