Dislocation Density from Etch Pits
Convert a counted number of etch pits on a measured field area into a dislocation density per square centimeter. Formula: D [1/cm²] = N / (A [µm²]·1e-8), where 1 µm² = 1e-8 cm², N is integer pit count ≥0, A>0 µm². Output D≥0 1/cm²; D=0 when N=0. Assumes each pit corresponds to one threading dislocation, uniform distribution, and accurate field area measurement.
Description
Convert a counted number of etch pits on a measured field area into a dislocation density per square centimeter. Formula: D [1/cm²] = N / (A [µm²]·1e-8), where 1 µm² = 1e-8 cm², N is integer pit count ≥0, A>0 µm². Output D≥0 1/cm²; D=0 when N=0. Assumes each pit corresponds to one threading dislocation, uniform distribution, and accurate field area measurement.
Dislocation Density from Etch Pits is a focused tool for the following task. Convert a counted number of etch pits on a measured field area into a dislocation density per square centimeter. Formula: D [1/cm²] = N / (A [µm²]·1e-8), where 1 µm² = 1e-8 cm², N is integer pit count ≥0, A>0 µm². Output D≥0 1/cm²; D=0 when N=0. Assumes each pit corresponds to one threading dislocation, uniform distribution, and accurate field area measurement. It reports Dislocation density from the values you provide rather than inventing measurements, coefficients, or professional judgment that are not part of the input.
When to use Dislocation Density from Etch Pits
Use this semiconductor calculation for first-order device, material, fabrication, interconnect, packaging, or reliability estimates when every coefficient and unit convention is known.
- Pit count
- Required integer. Number of etch pits counted on the field. Must be a safe integer at least 0; 0 yields 0 density.
- Field area (µm²)
- Required number in µm². Measured field area under the microscope. Must be greater than 0 µm².
The cited overview of Semiconductor device supplies background for the terminology and domain context used by this tool.1
How Dislocation Density from Etch Pits works
Convert a counted number of etch pits on a measured field area into a dislocation density per square centimeter. Formula: D [1/cm²] = N / (A [µm²]·1e-8), where 1 µm² = 1e-8 cm², N is integer pit count ≥0, A>0 µm². Output D≥0 1/cm²; D=0 when N=0. Assumes each pit corresponds to one threading dislocation, uniform distribution, and accurate field area measurement. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.
- Dislocation density (1/cm²)
- Returned number in 1/cm². Dislocation density derived from the etch pit count. At least 0 1/cm².
Limitations and assumptions
- Material composition, geometry, process history, temperature, electric field, bias, interfaces, parasitics, and fitted parameter ranges can invalidate a compact semiconductor model.
- Pit count must be at least 0.
- Field area must be at least 5e-324.
- Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.
Alternative or Complementary approaches
Compare the estimate with measured process data, current device documentation, and a higher-fidelity circuit, field, thermal, quantum, or TCAD model when the decision requires it.
References
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Semiconductor device — Wikipedia contributors
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