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Engineering, 26.06.2020 16:01 isabua

Dependence of oxidation on the temperature 10 points total The process temperature is an important parameter for the oxide growth process. To get an estimate for the temperature dependence of the Deal-Groove formula, the following considerations can be used. All processes (transport, diffusion and reaction) that are used in the Deal-Groove model are thermally activated. Thus, the dependence on the growth parameters on the temperature T can be estimated by: X(T) = Xpe Xe{A, B, B/A} (5) Here kB = 8.617 x 10-5 eV/K is the Boltzmann Constant and EX is the activation energy for the parameter. X, is the value for the corresponding parameter at T =0 K. Please note that this is not a 'physical activation energy but rather an average/fit parameter for all the physical and chemical thermally activated processes relevant for the process. In the original publication by Deal and Groove, they gave the following parameter sets for dry oxidation: Oxidation temperature in 'C A in um Bin um²/h 1000 0.165 0.0117 1200 0.040 0.045 a)EXct and X, for A, B and B/A a) Use the given values for the parameters A and B in the table above, along with equation ?? to derive the activation energies EXd and zero temperature values X(T = 0 K) for all three parameters A, B and B/A. Then use this calculate the corresponding values of A, B, B/A for the following temperatures: 1000°C, 1200°C, 800°C and 900 °C.
b) Plot estimates for other temperatures 2 points Use the obtained values from the previous sub-task along with the full Deal-Groove model equation for Z:(t) to plot the oxide thickness over time (0-100h) using at least 20 data points each for the following temperatures: 1000°C, 1200°C, 800°C and 900 °C. Assume Zo = Om.

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