ESS553 Midterm Review

For the given initial and boundary conditions, which method should you use to calculate the concentration profile?

• Thin-Film Solution

• Error Function Solution

• Fourier Series Solution

• Laplace Transform Method

For a Cu-Sn diffusion couple, which side will you expect to see the Kirkendall voids? (T_m,Cu = 1085^oC, T_m,Sn = 232^oC)

• Cu-rich side

• Sn-rich side

• Both sides

• The dark side

Under which of the following conditions will high diffusivity paths (快速擴散路徑) dominate the diffusion process?

• Low defect density (低缺陷密度)

• High temperature (高溫)

• Low temperature (低溫)

• Short diffusion time (短時間)

From the atomic model of diffusion and random walk theory, the root-mean-squared displacement of an atom in 3D is?

If a material process operates through serial (串聯) reactions, which reaction will dominate the reaction rate?

• The slowest (最慢) reaction

• The fastest (最快) reaction

• The coolest (最酷) reaction

• The hottest (最辣) reaction

When calculating interdiffusivity, the diffusivity of the element with a lower concentration will contribute more to the calculated value.

• True

• False

Given the melting temperature (熔點) below, which element, at the same temperature, should have the slowest (最慢) self-diffusion rate?

• Cu (1083^oC)

• Ag (961^oC)

• Al (660^oC)

• Ni (1455^oC)

For a drive-in doping process (thin-film solution), under what condition will the solution error be less than 0.1%?

If two elements do not like to mix with each other, how is the thermodynamic factor compared to 1?

• Higher than 1

• Lower than 1

• Equal to 1

• Faster than 1

Which process should result in the shown carbon (C) concentration profile?

• Carburization (滲碳)

• Decarburization (脫碳)

• Carbon deposition (積碳)