A silicon semiconductor is in the shape of a rectangular bar with a cross-sectional area of 100 m, a length of 0.1 cm, and is

A silicon semiconductor is in the shape of a rectangular bar with a cross-sectional area of 100 μm, a length of 0.1 cm, and is doped with 5x 10 ¹⁶ cm ^-3 boron atoms and 1.5× 10 ¹⁷ cm ^-3 arsenic atoms. The electron and hole mobilities as a function of doping are shown below. The temperature is T= 300 K. Assume n _i =10 ¹⁰ cm ^-3 .

(a) Determine the current if 5 V is applied across the length.

(b) What fraction of the current is carried by the holes and by the electrons?

(c) Calculate the average drift velocity of the electrons

(d) How would the drift velocity change if the sample length were reduced to 10 μm? How long would it take an electron to drift this distance?

1500 Electrons Temperature = 300 K 8 1000 Holes 500 104 10t5 106 107 1045 1019 Doping Concentration (cm) 10 Mobility (cm/V sec)