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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I want to replace zinc oxide with aluminum oxide in a DIY transistor
I want to assemble a DIY transistor from plastic and aluminum oxide. On this site I also found this document:
https://www.andaquartergetsyoucoffee.com/wp/wp-content/uploads/2009/05/zinc-oxide-...
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When does the transistor reach the stable status when I add resistor to the emitter
simulate this circuit – Schematic created using CircuitLab
If I add resistor R3, which is an emiter resistor, can it change the value of the base voltage? I've learned that the emmiter voltage ...
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Diodes in parallel reduce current compared to single measurement
I have a photonics integrated circuit with two quantum well diodes. (exact description below)
If I measure the IV curve for each individual diode I get pretty much the same curve for both. but if I ...
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How to mitigate excessive ringing in VDS and VGS
I have a few questions regarding my measurement results in the lab for a double pulse test setup. There are three issues which I want to mitigate
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At turn-on interval, there is excessive ringing in ...
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RC snubber network not protecting IGBT
I'm working on an electromagnetic accelerator project but I'm having trouble protecting my IGBTs that switch current through the coils. Here's the schematic:
C1 gets charged to around 250 V (In my ...
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Reasoning behind the density of free electrons/holes being constant with respect to volume of a semiconductor material
Consider a silicon semiconductor material which is having a cuboid shape of dimensions \$2\times 2\times 1\ \mathrm{cc}\$, suppose the atomic density of silicon is \$10^{22}/\mathrm{cc}\$, so in all ...
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Difference in simulated and measured Eon, Eoff and Erevreq for double pulse test conducted on a MOSFET
I conducted a double pulse test (DPT) on an AUIRFP4568 MOSFET in the lab as well as in LTspice. With the same setup as used in the lab I created a setup in LTspice using the SPICE model of the MOSFET. ...
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dv/dt capability comparison of two MOSFETs
I am doing a datasheet comparison of the AUIRFP4568 and the IXTH150N15X4 MOSFETs. The MOSFET is for a three phase inverter working as MCU (Motor Control Unit) to control a PMSM motor, and will be ...
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Conduction losses calculation of a SiC MOSFET
I have a question regarding conduction losses calculation of a SiC MOSFET. What I found in different research papers and in application notes is that you calculate the power dissipated during forward ...
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Can an intrinsic semiconductor not be used as a base?
I'm studying transistors. After having learned how a transistor works, I can't help thinking that we could have an intrinsic semiconductor as a base.
This is because it would reduce recombinations. ...
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What does the interface between lead(s) and the silicon chip look like inside a semiconductor package?
For a leaded semiconductor, like a diode or a transistor, one of the leads is usually the same piece of metal as the copper pad/heat spreader on the back, which is also shorted to one of the junctions ...
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A question about basic band gap theory
I always encounter assertions similar to the following quote:
The electrons in the conduction band have higher energy than those in the valence band of a semiconductor.
We know by definition the ...
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What is the type of material used for the casing of semiconductors?
I am trying to build some thermal models for leaded and surface-mount diodes and transistors.
Below is a picture of the TO-220 outline I got from the internet. What kind of material is the black part ...
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Why does higher temperature decrease NMOS threshold voltage?
The threshold voltage of a MOSFET decreases as temperature increases.
I don't understand this. Consider an n-type MOSFET that is fabricated in a p-doped silicon substrate. For a channel/inversion ...
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Adapter for a function generator output
I want to order this adapter, but I can't find it on the web. Can anyone please confirm the exact name of this adapter for a function generator having a channel output and terminals for a DC power ...
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Does electricity linger in small electronics?
I'm designing a very tiny 8 bit CPU as a concept first in CircuitVerse. I designed components to eventually design this 4 bit 0-15 binary counter. Only thing I found weird is when the ALU is enabled, ...
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How do the BJT collector and emitter portion compare in terms of size and charge density?
The diagram of a BJT implies that the two p-n junctions are identical. However, I do know that they are not since we cannot connect the transistor the other way around i.e swap emitter and collector, ...
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Clarification of 'case' in junction to case thermal resistance
Junction to case thermal resistance (Rjc) is a key parameter when characterizing a package. It can be expressed as the temperature difference between the two locations over the heat dissipation.
I am ...
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How does one manufacture a P-N junction?
When I read a physics textbook about a P-N junction, it will tell me that you connect a P-doped semiconductor to an N-doped semiconductor, and you form a depletion region.
From what I know about ...
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What does this schematic symbol mean (transistor with two emitters)?
Basically the question is, what it is?
Are those two emitters (meaning that part of semiconductor heavily doped)?
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What does the 'junction' of a silicon semiconductor look like in real-life?
The P-N junction is a small area within a package where heating is most prominent. Junction temperature is a key parameter we try to track when operating a diode or a transistor.
I am wondering what ...
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Why do we use LDD technique in IC fabrication technology?
Why do we use LDD(lightly doped drain) in IC fabrication technology?
In the "silicon VLSI technology" book, was mentioned that this is in order to create a voltage drop in drain region. So ...
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Why is the MOSFET not behaving as per standard device characteristic curve?
A MOSFET has 3 modes of operation:
1.Vgs < Vth => Cutoff
2. Vgs > Vth and Vds < Vgs − Vth => linear region
The MOSFET operates like a resistor, controlled by the gate voltage relative ...
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Bandwidth: voltage-source vs. current-source gate drivers
Why do voltage-source gate drivers provide low-to-medium bandwidth that does not work well for wide band gap devices, while current-source gate drivers provide hundreds of MHz of bandwidth?
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What is the reason why thermal aging affects only the Cds capacitance but not the Cgs or Cgd capacitances?
Please take a look at the following images, experimentally obtained from a power cycling test of a power MOSFET. After the test where thermal aging is created due to repetitive power cycles, it is ...
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Is there anywhere I can download BJT Transistor I-V data?
Is there anywhere I can download some current-voltage data for a bipolar junction transistor? (It doesn't matter that much which one.)
To explain further, for a simple BJT circuit we have the ...
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How to calculate accumulation charge concentration (/cm3) as a function of dist. from the oxide-semiconductor interface in a MOS cap with n-type semi?
I am trying to calculate the accumulation charge concentration (/cm3) for the MOS capacitor with Au/TiO2/n-InSb, where n doped InSb is the substrate. So far the material I found focuses on p-type ...
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Can we make a battery with a semiconductor?
Can we make battery with separate P and N junctions?
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Why in the output characteristic graph of BJTs, within the saturation region, is the collector current positive?
It is known that in the saturation region of the BJTs the pn junction is reverse biased. The reason for being reversed biased could be explained as follow:
Vce=Vcb+Vbe
Therefore
Vcb=Vce-Vbe
We can see ...
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What are wettable flanks in semiconductor packages?
What are wettable flanks? Is there any difference between packages with wettable flanks and other leadless packages?
Can we say the package given above has wettable flanks?
