introduction to semiconductors

The term semiconductor arises from

• resistor-like properties of metal oxides

• variable conductive properties of some materials

• the fact that electrons conduct better than holes

• insulating properties of silicon and GaAs

Which of the following is not an advantage of semiconductor devices over vacuum tubes?

• smaller size

• lower working voltage

• lighter weight

• ability to withstand high voltage spikes

Of the following substances, which is the most commonly used semiconductor?

• Germanium

• Galena

• Silicon

• Copper

GaAs is

• a compound

• an element

• a mixture

• a gas

A disadvantage of MOS devices is the fact that

• the charge carriers move fast

• the material does not react to ionizing radiation

• they can be damaged by electrostatic discharges

• they must always be used at high frequencies

Selenium works especially well in

• photocells

• high-frequency detectors

• RF power amplifiers

• voltage regulators

Of the following, which material allows the lowest forward voltage drop in a diode?

• Selenium

• Silicon

• Copper

• Germanium

A CMOS integrated circuit

• can only work at low frequencies

• requires very little power to function

• requires considerable power to function

• can only work at high frequencies

The purpose of doping is to

• make the charge carriers move faster

• cause holes to flow

• give a semiconductor material specific properties

• protect devices from damage in case of transients

A semiconductor material is made into N type by adding

• adding an acceptor impurity

• adding a donor impurity

• injecting protons

• taking neutrons away