Question

The diffusion coefficient for aluminum in silicon is DAl in Si= 4 × 10-13 cm2/s at 1300 K. What is a reasonable value for DAl in Si at 1600 K ? Note: Rather than performing a specific calculation, you should be able to justify your answer from the options below based on the mathematical temperature dependence of the diffusion coefficient assuming a positive activation energy for diffusion.

Answer 1

Answer:

D = 4x10^-11

Explanation:

an increase in temperature would cause a resultant increase in diffusivity. as temperature rises, thermal energy of atoms would also rise and this would cause them to go faster.

4x10^-11cm²/s satisfies this condition because there is a temperature increase from 1300 to 1600.

DAI in Si = 4x10^-13cm²/sec at 1300

DAI in Si at 1600

D increases

temperature also increases