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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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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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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Why is diffusion current due to p side in a diode inversely proportional to doping concentration of p side in the case of forward bias?
In a diode at equilibrium, there are Pn holes on the n side of the junction. These are maintained by the dynamic equilibrium of diffusion due to holes = drift due to holes. When a forward bias is ...
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Why is the common emitter input insensitive to base width modulation?
According to Robert F. Pierret (1996) in page 411 of the 2nd edition of the textbook Semiconductor Device Fundamentals, common emitter input of PNP BJTs is insensitive to base width modulation. Isn't ...
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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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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 do PMOS suffer a worse body effect than NMOS?
Gray, Hurst, Lewis, and Meyer give the following discussion around PMOS transistors which I followed except for the sentence which reads:
Good use can be made of this fact in analog circuits to ...
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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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Is there any specific application for an indirect band gap semiconductor?
I know that direct band gap semiconductors are very attractive for optical emission, and even though indirect band gap are used as well, I keep wondering: is there any technology that specifically ...
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What is the correct carrier concentration equation to use?
In this book I am reading, it gives the intrinsic carrier concentration as:
\$ n_i = \sqrt{N_c\cdot N_v} \cdot e^{({\frac{-E_g}{2*K*T}})} \$
While another book says the carrier concentration is:
\$ \...
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Photo-conductivity of n and p type semiconductors
Both n-type and p-type semiconductors are available to fabricate a
photoconductive devices. To achieve the highest photoconductivity, do
you want to use n-type or p-type? Why?
$$σ_{ph}=q(μ_n ∆n+...
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Why aren't semiconductor wafers diced into triangles?
Semiconductor wafers are circular, and usually they are divided into squares or rectangles. However it's more efficient to pack triangles into circles than it is rectangles, so less wafer area would ...
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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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Connecting phototriac substrate to adjacent pins
For a regulatory exercise I am analyzing the result of a short fault between a phototriac's substrate (MOC3023) and its anodes (one at a time). The datasheet warns ...
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