(vii) The process of adding an impurity to an intrinsic semiconductor is called (a) recombination (b) doping (c) atomic modification (d) ionization (viii) The depletion region is created by (20) (a) ionization (b) diffusion (c) recombination (d) answers (a), (b), and (c) (ix) The term bias means (a) the ratio of electrons to holes (b) the amount of diode current (c) applied dc-voltage to control the device (d) answers (a), (b), and (c) (x) For a silicon diode, the value of the forward bias voltage typically (a) must be greater than 0.3 V (b) depends on carrier concentration (c) depends on depletion region width (d) must be greater than 0.7 V