ABSTRACT
FIGURE 5.1 Bohr model for the phosphorus donor in silicon (or germanium), where P+ is the ion and e− is the electron.
and inserting Equation 5.5 for r yields
(5.9)
E m e n
=− ∗1
2 4 14
The donor binding energy Ed is the energy required to bring the electron from the ground state (n = 1) to the conduction-band minimum, here set to be E = 0:
(5.10)
E m e m md
= =
∗ ∗1 2 4
13 6 1 4
( . ) piεε
eV ε
On an energy band diagram, the donor level (0/+) is indicated by a horizontal line an amount Ed below the conduction-band minimum (Figure 2.2).
