Questions tagged [semiconductors]
Most generally a class of materials that are neither insulators or conductors in their natural state, but which can be manipulated via doping or electric fields to change their conduction state. Silicon, Germanium, and GaAs are some usual materials. The term is also used to speak about devices that are made from such materials, for example, a processor from Intel can be called a semiconductor.
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Why isn't there a potential difference across a disconnected diode?
I know this question sounds silly, as if there was a potential difference a current would be created when the terminals are connected together and this would mean energy has come from somewhere.
The ...
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Can a thyristor be built from two transistors?
Supposedly, an SCR/thyristor is just a simple, four layer PNPN semiconductor.
If that's the case..
When a circuit calls for a SCR/thyristor, and there isn't one available, can it be substituted by (...
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Transportation of holes
I was studying pn junctions and came across the concepts of diffusion currents. From what I understand is, when the junctions come together, since there is an excess of donors on the n side and an ...
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Why is the temperature range of industrial and military products so high?
From Wikipedia the common temperature range for electrical components is:
Commercial: 0 to 70 °C
Industrial: -40 to 85 °C
Military: -55 to 125 °C
I can understand the lower part (-40°C and -55°C) ...
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How should I understand the intrinsic body diode inside a MOSFET?
I know there is an intrinsic body diode inside all the MOSFETs, but I'm confused about the reason why it's there. I've searched the articles but can't find a good explanation for it. Can anyone use ...
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Does MOSFET let current flow through source to drain as it allows it from drain to source?
Does a MOSFET allow current flow in reverse direction (i.e.; from source to drain)?
I made a Google search, but couldn't find a clear statement about this matter. I have found this similar question, ...
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What is the physical model for energy flow in or around a lossless conductor during transient analysis? (Veritasium Electricity in Wires)
Context
Veritasium - The Big Misconception About Electricity - Energy Doesn't Flow in Wires
Note I do not agree with the answer (D) given by Veritasium which is only plausible if any tiny current ...
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Transistor(BJT) as Two Diodes
With reference to Vasiliy's answer on this question
Why can't two series-connected diodes act as a BJT?
"excess electrons from the P side of the forward biased diode can not be swept to the P ...
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Why does a p-type conduction band have higher energy then n-type conduction band in a p-n junction?
In an energy band diagram that represents the p-n junction (during equilibrium) the p-type conduction band has greater energy then an n-type conduction band. Why does the p-type have greater energy ...
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MOSFET common source amplifier output impedance calculation
What I've read in microelectronic texts like Prof's Razavi's Fundamentals of Microelectronics is that for calculating output impedance, one has to make all independent sources 0, i.e., short all ...
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Where are the depletion PMOS transistors?
In school, I was taught about PMOS and NMOS transistors, and about enhancement- and depletion-mode transistors. Here's the short version of what I understand:
Enhancement means that the channel is ...
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What is silicon germanium (SiGe)?
I've heard that SiGe chips can be faster than ordinary silicon chips.
What is SiGe and why is it faster than ordinary silicon?
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Resistance of a semiconductor diode
When we calculate the dynamic resistance \$r=(\frac{dv}{dI})\$, for any n-p junction, how is it different from the normal resistance \$R=\frac VI\$? Does the equation for the voltage drop (The fermi ...
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Flyback Diodes and Relays
I'm wanting to use a relay as a SPST switch, and I've noticed many designs incorporate a flyback diode. What instances are these needed and what are potential drawbacks, if any?
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Are BJTs used in modern integrated circuits to the same extent as MOSFETs?
On modern integrated circuits, are there as much BJT's on the chip as MOSFET transistor? If not, why?
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