The discussion revolves around the meaning of "standard" in the context of gas flow rates measured in standard cubic centimeters per minute (sccm). Participants explore the implications of standard conditions on gas flow measurements, as well as related calculations for gas deposition in a vacuum chamber.
Participants express differing views on the definition of "standard" and the conditions that apply, indicating that multiple competing interpretations exist. The discussion remains unresolved regarding the precise implications of these definitions on calculations and applications.
There are limitations in the discussion regarding the assumptions made about standard conditions and the specific parameters required for accurate calculations in gas flow and deposition scenarios.
Ravian said:say Al is evaporated in a vacuum chamber to form a thin film of AlN, say flow rate of N2 is 5sccm and deposition rate is 1 angstrom/s. then in 10minutes how thick film of AlN is formed? does in this case we need to consider voltage and current values (used to evaporate Al) also in order to estimate film thickness?
Dr Lots-o'watts said:... and the shape of the plasma, and the shape and size of the chamber, and possibly many other things. Have fun.
Q_Goest said:The term "standard" refers to standard conditions, usually 68 F and 14.7 psia (in the US). You'll find however, that different industries take liberties in defining standard conditions. I believe there are European industries that define standard conditions as 0 C (not sure the pressure they use). You should ask whoever gave you the values to define standard conditions for you if you need something any more accurate than that.
Wikipedia said:The current version of IUPAC's standard is a temperature of 0 °C (273.15 K, 32 °F) and an absolute pressure of 100 kPa (14.504 psi, 0.986 atm)[1], while NIST's version is a temperature of 20 °C (293.15 K, 68 °F) and an absolute pressure of 101.325 kPa (14.696 psi, 1 atm).