All Questions
Tagged with vlsi semiconductors
15
questions
1
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2
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143
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Why do series NMOS do better than a single NMOS from a delay perspective?
My VLSI text (Weste and Harris) writes the following:
Transistors in series drop part of the voltage across each transistor and thus experience smaller fields and less velocity saturation than single ...
- 1,161
0
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1
answer
478
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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 ...
- 442
3
votes
4
answers
3k
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How do processor transistor counts keep increasing, without geometric scaling?
Reading into the history of the semiconductor industry and Moore's Law, and looking at the ITRS/IRDS documents, I understand that scaling down and modern node names (7nm, 5nm etc) are now "...
- 31
1
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2
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2k
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Why is an N-type MOSFET used for low-side and a P-type for high-side switching?
Typically an N-MOSFET is used for low-side switching and P-type for high side switching. That's why transmission gates use both an N and a P-type MOSFET.
But I don't understand how a P-type for low-...
- 2,519
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2
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753
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How does logic 1 get passed through an NMOS pass transistor?
I'm studying pass transistors. One thing I came across in several of the books is that when an NMOS has a logic state HIGH and the input terminal (the schematic below) is also HIGH, the output ...
2
votes
1
answer
173
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What is the current state of the art design rule for SiC VLSI? Technological impediments to making a SiC microcontroller for a Venus lander at 460 °C?
A sub-discussion below Is there any demonstrated or even proposed technology that can sterilize a spacecraft with 100% certainty and yet leave it electronically functional? in Space Exploration SE ...
- 3,439
1
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2
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484
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Why can't conductors be used in making ICs (integrated circuits) instead of semiconductors? [closed]
I really wanted to ask why we can not control flow of electrons in conductors.
Can I not say if a current is flowing in a conductor it is 1 and when I disconnect the supply it is 0.
Can you elaborate ...
- 11
3
votes
1
answer
897
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What exactly do the well taps in MOSFETs do and how?
Do they affect the flow of charge carriers or charge concentrations at all in the device? How so? Up to this point I've tried to visualize the effects that the various doped areas had on device ...
- 267
0
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2
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79
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Is there any research for chemical/structural method to prevent observing beneath chip packaging? [closed]
I want to prevent others from reverse-engineering the on-die ROM, using X-ray, microscope, etc..
I think it's best to inject some substance between chip and packag and when the chip package is ...
- 177
2
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4
answers
2k
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Why propagation delay is measured at 50% of the input and output waveform?
I didn't find the concept of propagation delay measured at a particular point on the waveform.
- 21
0
votes
1
answer
441
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Why does the current in MOSFET have a quadratic function (explain logically without using the integration method)?
The current equation relating Vds ,Vgs and Vt is already known to us ,but if there is any way we can find out how it varies quadratically without using the formulae?
- 21
1
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1
answer
840
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Calculating resistance for metal layer from LEF File
I have a .LEF File which has various metals description and their parasitics information. I am trying to calculate R. It is specified as RPERSQ = 0.278.
In the File description it is written as ...
0
votes
1
answer
2k
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Inter die vs Intra die process variation
Due to fabrication process, there will be variations, among wafers as well as among dies across a wafer.
My question is that what variations are significant between dies? And what variations are ...
- 219
1
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1
answer
2k
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N-Well Resistor
So as I'm currently looking into basic VSLI, I made a simple voltage divider in Electric using N-Well resistors. I was hoping to understand: Why does an N-well act as a resistor? A reference to better ...
- 13
2
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0
answers
132
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Does the Black's equation work for immortal wires / interconnections (or only for mortal ones)?
I'm trying to understand whether the Black's equation is only true for mortal wire / interconnections or it is also applicable to immortal wires (essentially when its \$jL\$ product is less than \$jL_{...
- 121