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ALD GPC & Temperature Window Calculator
Enter film thickness and cycle count to get growth per cycle, or input GPC-vs-temperature data to identify the temperature window. Both calculations run in your browser with nothing sent to a server.
Growth per cycle
GPC (unit / cycle)
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Cycles needed
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Temperature window check
Calculated in your browser. Nothing is sent to a server.
How it is calculated
Part A computes growth per cycle: divide total thickness by the number of cycles to get GPC (e.g. Å/cycle or nm/cycle). Enter a target thickness and GPC to get the number of cycles needed, rounded up to the next whole cycle.
Part B identifies the temperature window. Enter rows of temperature and GPC. The tool sorts by temperature and finds the longest consecutive run of points whose GPC stays within ± tolerance (default 5 %) of that run's median. It reports the low and high temperature bounds and the plateau GPC.
The temperature window is defined by self-limiting, saturated growth — adding more precursor dose does not raise GPC. GPC can still drift slowly within the window. Below the window, GPC may rise (condensation) or fall (insufficient thermal energy). Above it, GPC may rise (precursor decomposition, CVD-like growth) or fall (desorption, dehydroxylation).
A higher GPC above the window does not mean a better process. Within and near the window, also check film density, refractive index, and impurity levels to confirm process quality.
Limits to keep in mind
- A flat GPC band is necessary but not sufficient to confirm the temperature window. Run a precursor dose saturation test at each temperature to verify self-limiting growth.
- The tolerance percentage is a user-adjustable parameter, not an industry standard. Adjust it based on your process requirements and measurement uncertainty.
FAQ
- What does GPC stand for?
- Growth per cycle — the thickness deposited in one ALD cycle, typically reported in Å/cycle or nm/cycle.
- How does the temperature window detection work?
- The tool sorts your data by temperature and searches for the longest consecutive run of points whose GPC values all fall within ± tolerance of the run's median. The endpoints of that run define the window.
- Why might GPC rise above the temperature window?
- Precursor decomposition can produce CVD-like growth, depositing more material per cycle. This is not self-limiting and typically degrades film quality.
- Is a flat GPC enough to confirm the temperature window?
- No. A flat GPC band is necessary but not sufficient. Confirm self-limiting growth with a dose saturation test at each temperature, and check density, refractive index, and impurity content.
Read the full article
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