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(8 pts) For the predeposition heat treatment of a semiconducting device, gallium atoms are to be diffused into silicon at a temperature of $1150^{\circ} \mathrm{C}$ for $2.5 \mathrm{~h}$. If the required concentration of $\mathrm{Ga}$ at a position $2 \mu \mathrm{m}$ below the surface is $8 \times 10^{23}$ atoms $/ \mathrm{m}^{3}$, compute the required surface concentration of $\mathrm{Ga}$. Assume the following: (i) The surface concentration remains constant (ii) The background concentration is $2 \times 10^{19} \mathrm{Ga}$ atoms $/ \mathrm{m}^{3}$ (iii) Pre-exponential and activation energy values are $3.74 \times 10^{-5} \mathrm{~m}^{2} / \mathrm{s}$ and $3.39 \mathrm{eV} / \mathrm{atom}$, respectively. Please select file(s) Select file(s)

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VV7BML The First Answerer