9.6 Semiconductors and Doping

Donor and acceptor impurities shifting levels into the gap, n-type versus p-type carriers, and Hall-effect measurement of carrier sign, density, and drift velocity.

University Physics Volume 3, 9.6 Semiconductors and Doping

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5 exercises

9.6 Exercise 1

What kind of semiconductor is produced if germanium is doped with (a) arsenic, and (b) gallium?

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9.6 Exercise 3

What is the Hall effect and what is it used for?

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9.6 Exercise 5

For a p-type semiconductor, how do impurity atoms alter the energy structure of the solid?

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9.6 Exercise 7

Suppose that the cross-sectional area of the strip (the area of the face perpendicular to the electric current) presented to the in the preceding problem is $1 \text{mm}^{2}$ and the current is independently measured to be 2 mA. What is the number density of the charge carriers?

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9.6 Exercise 9

The Hall effect is demonstrated in the laboratory. A thin rectangular strip of semiconductor with width 5 cm and cross-sectional area $2 \text{mm}^{2}$ is attached to a battery and immersed in a field perpendicular to its surface. The Hall voltage reads 12.5 V and the measured drift velocity is 50 m/s. What is the magnetic field?

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