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 aren't the majority charge carriers attracted by terminals of a battery when the p n junction is reverse biased?
It is clear that when the junction is reverse biased, the free electrons from the n side can not pass the depletion layer and fill the holes in the p side. But why will the free electrons not move ...
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Semiconductors: electrons more mobile than holes despite being heavier?
I apologize if this is a very basic question. But I have always known it to be true that in Silicon, electrons have higher mobility than holes. From my semiconductor physics classes in first year, the ...
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Power dissipation vs. heat dissipation for transistors and diodes
Are these two concept the same or different for semiconductors? Some power MOSFETS have power ratings in the hundreds of watts, and that's way too high for heat loss.
I try to understand 'power ...
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Does body diode reduce MOSFET switching loss in a power converter?
In power converters, it is common that MOSFETs are fed a PWM signal to have cyclic switching. Part of the power is lost in the process. Does the body diode reduce this loss? It seems most power ...
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Why is a Zener diode's temperature coefficient ±0mV/K at approximately 6V?
I am familiar with Zener diodes and their parameters.
It's interesting to see the same temperature coefficient at approximately 6V across different manufacturers and different packages. See below ...
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MT3608 wrong output voltage
I designed a 24V boost converter circuit using a input voltage of 5V shown below:
After producing the PCB for this, I tested the output voltage and found that the output voltage was at 5V instead of ...
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Is there a microscopic oscilloscope probe?
Does such a device exists to measure voltage and current in 14nm and below semiconductors?
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What is Electromagnetic Cross Section?
What is Electromagnetic Cross Section?
(shock section)
Hello, I have a question regarding the manufacturing process of electronic components in the case of the silicon deposition and corrosion process....
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Why can't a P-N junction diode be used as a voltage regulator or reference in forward bias?
Usually, a Zener or avalanche breakdown region for a suitably doped P-N junction is used for voltage regulation as a substantial variation in the current (due to minority carriers) requires a ...
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Why do we dope low amount of impurity atoms in a semiconductor?
I read that the doping ratio is usually around 1 impurity/10 million atoms. Why is that ratio so low? Can’t the semiconductor conduct electricity better if there were more charge carriers?
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PN circuit, playing with doped wafers
So I have two silicon wafers. One is P type (doped with boron) and one is N type (doped with phosphorus). I am just playing around with these and thought to myself, "can I make a diode if I ...
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What is the law regarding certification of paper electronics for EU and US
The question is explicitly aimed at paper electronics. No classic/typical PCB (fiber glass or typical material PCB's are made of) is attached to the paper. The circuit layout is directly printed/...
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Do conduction electrons recombine with positive donor atoms?
Once the 5th valence electron of a donor atom left, it will be to the conduction band, so the donor atom becomes positively charged.
My question is if it is possible, that a free electron from the ...
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Hole current in p-type semiconductors
I know about p-type semiconductors and that there are holes as majority carriers present in the semiconduction. If we apply current through this semiconductor electrons from the valence band will come,...
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Do holes in a semiconductor just move when there is a current going through the semiconductor?
If a current travels through a semiconductor holes travel to the "end" of a semiconductor, where they can recombine with incoming electrons. Does this also occur if there is no current ...
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Why does touching LEDs' ground terminal light them dimly?
Today I was making a little circuit with an LED strip (3 LEDs in series) and I noticed a curious fact that I am not sure how to explain. I wasn't sure of the operating voltage of the LED strip, so I ...
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Why is intrinsic carrier density only equal to hole - or electron concentration?
If carriers can be holes or free electrons, why isn´t the intrinsic carrier concentration equal to the sum of the free electron concentration and the hole concentration in the semiconductor?
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Is generation and recombination same in extrinsic semiconductors?
For example, if we have an n - type semiconductor, so there are more electrons in the conduction band. So wouldn´t the recombination rate increase, opposed to the generation rate, because there are ...
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Reset on lockup, by discrete analog components [closed]
Way back when in the 80s/90s in a C64 magazine was an electronics project described. By adding a piece of code, the C64 would send a signal (pulse of power) to the electronics. If that stopped, the ...
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Feasibility of building a benchtop chip fab for prototyping
This is generally quite a vague question as I'm new to the space but I've been thinking a lot about prototyping in the IC/semiconductor space and have been wondering about the feasibility of ...
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Relation between collector current and Vce voltage in saturation mode
I have confusion regarding how collector current affects the voltage across collector to emitter in NPN transistor (2N4123).
How do I interpret this graph? Can I say when collector current increases ...
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Can I make a homemade Peltier module with constantan wire?
I'm trying to make my own Peltier module.
I ordered constantan wire, which I used as N-type semiconductor and iron wire as P-type.
I made this and powered it with 3V, but without response.
What am I ...
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Potential distribution in MOSFET
Let us assume that an NMOSFET has its source, drain and substrate grounded therefore VDS and VSB=0 V . We apply a gate voltage VGS=2 V and I want to know how this potential is distributed as we move ...
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How to calculate the total power of a LED using solid angle?
I have a LED with the max power of 130mW/sr and an opening angle of +-10° (so approx. around 20°). I conducted an experiment using this LED, the LED shines light to an un-doped silicon semiconductor ...
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Select zener for minimal thermal drift
The voltage of a Zener diode in the Zener breakdown region depends on temperature. Suppose we have 3 Zeners with the following specs:
3.3 V rated Zener voltage at 5 mA
5.1 V rated Zener voltage at 5 ...
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BJT: definition of "edge of saturation"
The book Sedra/Smith (Microelectronic circuits) tells in chapter 5 the following:
My question: I found no statement on why the EOS is defined by the point where vc < (vb - 0.4V).
Seems like other ...
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Could we use holes in an NMOS?
In an NMOS we have a p-substrate, and we use a positive voltage to attract negative charge "to the top". But could we have used negative charge to attract holes instead and gotten a "...
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Has any implementation succeeded to have shared key inside chipset and protect it from exploits?
Since there is a lot of demonstration like using SEM (Scanning Electron Microscope) to read bits from ROM through the scanned image of chipset, is there any implementation that has managed to succeed ...
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Why BJT thermal voltage can be not equal to kT/q in SPICE3
In SPICE, apart from effects such as basewidth modulation and base-collector leakage the collector current is given by the expression (according to the original SPICE2 PhD work)
But actually, ...
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What would a theoretical Group II, Group IV Transistor's Properties be? [closed]
This question is for more than a theory.
I would like to disprove that what I'm working on is not a Group II, Group IV transistor.
I know they CAN exist. I don't know why they don't exist or what ...
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