Problem 1
Suppose that you are using a piece of semiconductor as a Hall effect device to measure a magnetic field. You supply a DC current through the device. You would like to replace the piece of semiconductor with another one that will give a larger out put for the same external magnetic field. List two ways you can change the piece of semiconductor so that the output would increase. (Specify both the property and whether it would need to be increased or decreased.)
Problem 2
A piece of p-ty pe semiconductor is used as a Hall effect device. The device has a thickness of \(d_{\text {thick }}=1 \mathrm{~mm}\). It is placed in an external magnetic field of \(|\vec{B}|=10^{-5} \frac{\mathrm{Wb}}{\mathrm{cm}^{2}}\). A Hall voltage of \(5 \mu \mathrm{V}\) is measured when a current of \(3 \mathrm{~mA}\) is applied. Calculate \(p,\) the charge (hole) concentration in units \(\frac{1}{\mathrm{~cm}^{3}}\).
Problem 5
Two expressions were given for the Hall resistance: \(R_{H}=\frac{B_{z}}{q p} \cdot \frac{w}{l \cdot d_{t h i c k}}\) and \(R_{H}=\frac{h}{q^{2} n}\) Show that both expressions have the units of ohms.
