Questions tagged [manufacturing-process]
The manufacturing-process tag has no usage guidance.
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Functional discrepancy within PCBA batch
When manufacturing a small prototype batch of an embedded system at EMS I have detected different behavior between the units. All units work as expected, except that some units fail to operate same ...
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How do components not get knocked off or fall off during reflow?
I am looking at reflow ovens. A lot of them have a metal conveyor belt the boards sit on. On a double sided board, when you put the board on the metal belt, won't the metal belt knock components off ...
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Standard cell design flow in an ASIC design flow
I have a question regarding the standard cell design flow in an ASIC design flow.
That being said I understand what a gate array design flow is. It being more or less a fixed logic FPGA. Structured ...
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Can you (theoretically) reverse bias a BJT?
My understanding of how a BJT(bipolar transistor) works looks like this:
From https://www.allaboutcircuits.com/textbook/semiconductors/chpt-2/bipolar-junction-transistors/
Picture link: https://www....
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What's going wrong with my solder paste / mask?
A short question this - I've got a board with a QFN-32 0.4mm pitch footprint, I ordered this stencil, and a tube of this solder paste, and the result is in the picture below.
Now, I'm new to this, but ...
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What does it mean when it is said that an Intel CPU is assembled in Country X?
I was reading a same question posted on Quora but wanted to ask the same question here on this forum. So if the CPU states that it is assembled in some country X what does that mean exactly ? What ...
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Can through-hole leads be cut level with the PCB back while maintaining good connectivity?
If I'm using confusing terminology I apologize, this is relatively new to me and my first post on stack exchange.
My question is: Can through-hole leads be cut and filed level with the PCB back while ...
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Purpose of field implant in semiconductor manufacturing
I recently joined the semiconductor manufacturing industry.
In one of the process flows, I see a stage that has extra boron implantation step (called the field implant) in the P-WELL region.
I've ...
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Why do some exposed pads have small tabs, and does my PCB footprint need them?
I've noticed a few component packages now that have small "tabs" on the sides of their exposed pad (thermal pad). One example is the Analog Devices ADM7154 LDO:
Note the 0.356 x 0.457 mm ...
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Are there any resources on Column Last Attach Process? [closed]
I am trying to find resources about this process, but the only thing I have been able to find is the full form of the acronym CLAP any help is appreciated.
This process is used vehemently in the ...
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Is a cylindrical GAAfet fabricated with lithography and etching?
The GAAfet, aka the surrounding gate transistor (SGT), is basically a FinFET that surrounds the channel on all 4 sides instead of 3. However, a lot of examples show a cylinder instead of a rectangle.
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Why do old ICs especially CPUs have golden caps and bottom lids?
What was the advantage of having a golden heat spreader and bottom lid ?
Contacts make sense because of the electrical properties. This is still done today.
But what were the effects of using gold ...
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Calculations relating to carbon film resistor
Im researching on carbon film resistors and film resistors in general, hence I would like to know certain things:
Resistivity of carbon the film is made-up of? Does the resistivity depend on the type ...
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How were "old" chips manufactured, such as the 6502?
Recently, there have been several youtube vids (example) talking about how modern CPUs are manufactured. Basically, it's a complex nightmare of dropping molten tin and lighting it with light, which ...
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Environmentally sustainable electronics
I am part of my company's work to become more environmentally friendly and sustainable. On a high level for the company that means pursuing ISO certifications (such as ISO 14001) and working according ...
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