semiconductor quiz
What is a P-N junction? How does it behave when a voltage is placed across it?
is when N-type and P-type semiconductor join (or fuse) together, their materials behave in a very different merging together. When voltage is placed across it, it can either block or allow the flow of current.
Describe the function of a diode in a circuit? (What does it do?)
unidirectional semiconductor devices that only allow current to flow through them in one direction only, acting more like a one way electrical valve. Semiconductor devices that only allow current to pass in one direction.
Describe the significance of the parameter β for a transistor. How is β calculated?
β is current gain. β= Ic/ Ib
Sketch the I-V curve for an ideal diode. Indicate the forward-biased region, and the reverse-biased region. What is a typical value for the threshold (turn-on) voltage?
.7 volts
Name the 3 primary ways transistors are used in electronic systems.
A voltage amplifier, current amplifier, a switch (on/off)
Which transistor connection controls the operation of the device? What must happen for the transistor to turn on?
Base controls the operation of the device. To turn the transistor on, it must get a high input which will give out a low output.
One of the most important applications for diodes is in rectifiers. 9 What does a rectifier do?
Changes AC- DC, taking high voltage to low voltage
Explain the difference(s) between conductors, insulators, and semiconductors in terms of their atomic structure and electrical behavior. (Note: an example is not an explanation.)
Conductors: Materials that have very low values of resistivity. The low value allows them to easily pass an electrical current due to there being plenty of free electrons floating about within their basic atom structure. Insulators: exact opposite of conductors. They are made of materials that have very few or no "free" electrons floating about within their basic atom structure because the electrons in the outer valence shell are strongly attracted by the positively charged inner nucleus. Semiconductors: Between those of a "conductor" and "insulator". They are not good conductors nor good insulators. They have very few "free electrons" because their atoms are closely grouped together in a crystalline pattern called a "crystal lattice" but electrons are still able to flow but only under special conditions.
What device consists of a single PN junction?
Diode
Explain how doping changes the electrical properties of silicon.
It increases the conductivity
What types of material make the best conductors? Why? Name at least 4 conducting materials.
Materials that have low values of resistivity which allows them to easily pass an electrical due to there being plenty of free electrons floating about within their basic atom structure. Gold, Silver, Copper, Carbon
Explain the difference between p-type and n-type doped silicon.
P-type- absent of electrons; has holes N-type- has more electrons than holes
What two elements are the primary raw materials for semiconductor circuits?
Silicon and Germanium
What electrical property do these materials have in common: Glass, air, paper, wood, rubber, stone
They all have high values of resistivity meaning that electrical current can't pass through as easily (Insulators)
