Semiconductors WS2 Flashcards
When pure silicon is doped with a trivalent material, a X type material is produced with an excess of X
P, holes (free electron)
It has more holes as compared to free electrons. Hence holes are majority carriers
When pure silicon is doped with a pentavalent material a X material is produced with an excess of X.
N, electrons
Those electrons are available for conducting current.
What is mean when silicon has a negative temperature coefficient?
As temperature rises, resistance goes down so the conductivity increases.
What are the forward voltage drop for a silicone diode and germanium diode?
Silicon diode: 0,7 Volts
Germanium diode: 0,3 Volts
When reversed biased, does a silicon diode acts as a conductor or as an open?
Open
When using a DMM on the diode checker, what value does the meter read if the diode is good (approximate)
600mVolts
When using an analog meter to measure the resistance of a diode, what value will the meter read if the meter is forward biased? High or Low Ohms?
Low Ohms
The meter will read the reverse resistance. The diode is not good.
When installing a freewheeling diode, how should the diode be installed?
Reverse biais to load
When the negative side of the external bias voltage is connected to the P region of the diode (its anode+ part) and the positive side is connected to the N region (its cathode - part)
in this condition, the current can’t flow through the PN junction
What is the process called that mixes pure silicon and an impurity
Doping
What determines whether a material is a conductor or a semi conductor?
Number of valance electrons
Conductor: 1 - 3 Valence electrons
Semiconductor: 4
Insulators: 5 -8 electrons
Why is silicon used as semiconductor than germanium?
Withstand higher temperatures
What is the name of the device that sheds heat around a semiconductors?
Heatsink
A passive heat exchanger by an electronic device to a fluid medium (ex air coolant) where the heat gets dissipated.
When using an analog meter, how does one read the polarity of the internal battery?
- Through the outside of the meter: polarity reads + to -
- Through the actual battery: polarity reads - to +
