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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A problem regarding shift in the Fermi energy level [duplicate]
The effective mass of holes in a semiconductor is 5 times that of the electron, at what temperature would the Fermi level shift by 15 % from the middle of the forbidden energy band (given that, eg = 1....
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Miniaturization of semiconductor etch manufacturing equipment [closed]
What elements are necessary for miniaturization of semiconductor etch manufacturing equipment and what are their priorities?
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A problem from shift in the fermi energy level
if the effective mass of holes in a semiconductor is 5 times that of the electron, at what temperature would the fermi level shift by 15% from the middle of the forbidden energy band? (given that, eg =...
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Jump on varistor I/V curve when "passing" through max. leakage current region to max. clamping voltage region?
I'm taking a course on semiconductor physics and another on something like "usage of electronic devices". On both I've come across the I/V curve on a varistor, this is:
I cannot find the ...
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Simple circuit to bypass preamp when battery fails
A guitar has an on-board battery powered pre-amp between the pickups and the output jack. This is great until the battery fails, when it goes dead until the battery is replaced.
I would like to have a ...
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Noise in classical quantum transmission
In classical quantum transmission, we introduced a scattering model that includes two components: free projection and collision
Now, in this figure, this model is introduced that when it goes up in ...
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Series connection of diode and resistor. Why is there a constant voltage across the diode?
So I know that a diode can be described using the Shockley equation and after a certain voltage, the diode current begins to increase rapidly. The nominal 0.7 volts. I also know that this voltage ...
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How do you justify energy band bending in an unbiased MOS Capacitor?
Here is a MOS Capacitor:
(Image source: Chapter 5 of Modern Semiconductor Devices for Integrated Circuits by Dr. Chenming Hu)
Now lets consider the idea that the gate voltage is held at 0V, just like ...
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Carrier concentrations versus temperature and doping in Matlab
I am currently self studying structure of semi-conductors and I would like to make a graph in Matlab of the number of carriers as a function of temperature and doping. Let's say that I am testing ...
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Diffusion Current for Non-Linear Charge Carrier Configurations
Diffusion current in a MOSFET device can be calculated using Fick's Law per \$J=-qD\frac{d \rho}{dx}\$. It is often taken that the charge carrier configuration (\$\rho\$) across the MOSFET channel is ...
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Where is the flaw in this transistor, FET, Diode design?
I'm a hobbyist and I've designed and built (fabbed a small circuit board, schematic attached) a circuit to power a brushless DC motor using a solar panel which also charges a stand-by battery and ...
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What is a precise definiton of "cut-in" voltage as applied to diodes?
What is the "cut-in" voltage or knee voltage of a diode or transistor?
In a lot of books I read that the cut-in or knee voltage of a diode (or transistor) is when the diode starts conducting ...
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Semiconductor device testing [closed]
I'm a graduate engineer who's recently started a job testing silicon wafers consisting of both power MOSFETs or diodes and some IGBTs.
Unfortunately there's little in terms of support and training ...
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Electron holes and negatively charged particles [closed]
I'm studying BJTs and have a kind of legacy question. Is there any relation with electron holes and the positive charged point charges you'd see in simple Coulomb law applications?
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How to calculate the diffusion length in modulation doping?
I have read a paper about an application of modulation doping in bulk thermoelectric materials. In this paper, the nanoparticles diffuse carriers into the host materials, and I want to estimate the ...
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Bipolar Junction Transistor operating modes
If I use a BJT transistor as a switch, the transistor operates in the saturation or cut-off region, not in the active region.
However, some sources use the formula IC = β·IB. However, this formula is ...
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Why are microprocessors made using silicon and not germanium? [closed]
I heard that microprocessors are usually made using silicon, yet germanium has a better conductive state.
Why isn't germanium not chosen instead, taking to account that better conductors provide ...
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Calculate the absolute value difference in work function for two diodes
Given two semiconductor diodes where one is silicon and the other is called Graham, and both are connected by ideal wires that do not affect their work functions, and they are also in thermal ...
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Who is the manufacturer of the Y31 5133 mic?
My question is in this PCBA I need the information of the who is the manufacturers of the mic the full details of that mic...
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Can I measure the internal termination resistance of a MIPI receiver?
This question is further to: How accurate are internal terminators on chips with high speed differential inputs?.
I would like to measure the actual termination resistance inside one of these chips (...
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How accurate are internal terminators on chips with high speed differential inputs?
I'm aware that due to process variation, some analog parameters of semiconductor devices can vary; sometimes quite a lot. (E.g. the SST3904 transistor specifies a DC current gain somewhere between 100 ...
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Purpose of Schottky diode in this schematic
I have come across the power supply management section used in the Verdin Development Board, addressing overvoltage, undervoltage, overcurrent, and reverse voltage protection.
While I understand how ...
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Process compatibility between a non-planar avalanche photodiode and planar CMOS at 0.130μm process technology node
I plan to integrate a non-planar P⁺⁺/i/P⁺/N⁺⁺ avalanche photodiode (APD) array with a peripheral control circuit (e.g., trans-impedance amplifier, analog-to-digital converter, and quenching circuit) ...
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Why does light doping imply a large temperature coefficient?
In a discussion about how one can make integrated resistors in a given IC technology, Gray, Hurst, Lewis, and Meyer (Analysis and Design of Analog Integrated Circuits) remark that if we want to use a ...
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Limit of applicability of "quasistatic"/capacitive picture of devices
When analyzing the transitories associated with switching in semiconductor devices, in textbook treatments one often sees the time dependence considered by including (potentially nonlinear) capacitors ...
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Why doesn't side diffusion raise resistance of an integrated resistor?
Consider forming an integrated resistor by diffusion of n+ dopants down into some p- substrate (the corresponding pn junction is reverse biased during operation). Let \$W,L,t\$ be the width, length, ...
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Why are drain and source not actually perfectly symmetric?
In textbook treatments, one has that the source and drain of a MOSFET are completely symmetrical and therefore interchangeable -- the distinction is only made by which is at a higher voltage in the ...
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How do P-type transistors conduct current?
Going through a Introduction to Computing Systems by Yale N. Patt and Sanjay J. Patel and currently reading a chapter on MOS transistors. From what I understand, N-type transistors "close" a ...
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What is meant by Switching charge ( under Gate charge characteristics) in the given MOSFET datasheet?
What is switching charge in this MOSFET datasheet?
The switching actually takes place during Miller region. Hence I belive Qgd should be called as switching charge. But looks like the remianing gate ...
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Interpreting Diode-Module Datasheet (Voltage Drop)
I'm trying to interpret the datasheet of a Dual-Diode Module, specifically the MF200C12F2N. The internal Circuit Structure is given below:
The Forward Voltage is given as 2.3V without any further ...
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