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Semiconductors are more than just processors and GPUs

blog.robertelder.org

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Re: Semiconductors are more than just processors and GPUs

#21

Post by alted »

dragontamer wrote: post #16

Good overview, but he's missing one of the coolest applications of semiconductor / photolithography. MEMS. Micro-electromagnetic systems. The most common MEMS I can think of is the comb sensor, used for accelerometers in all of your cell phones. https://www.memsjournal.com/2010/12/motion-sensing-in-the-ip... The MEMS sensor for an accelerometer is quite simple. Take the nearest comb and smack it against a desk: you'l…

MEMS are awesome! Here are some other MEMS devices:

- hard drive read/write heads (the platters are debatable)

- inkjet printer nozzles (this is why making a DIY inkjet printer is nontrivial)

- air pressure sensors (e.g., for car tires)

- precise frequency filters for smartphone wireless communication

- oscillators (https://news.ycombinator.com/item?id=18340693)

- very tiny microphones for smartphones (speakers are harder)

- Digital Micromirror Devices (DMDs): arrays of tiny mirrors used in most projectors

- microfluidics ("lab-on-a-chip" stuff for fast disease testing, DNA sequencing, cell manipulation, etc)

And a couple other semiconductor applications:

- LCD/LED screens (monitors, phones, laptops, etc) (these are made on a glass surface instead of a silicon wafer but use the same basic manufacturing techniques)

- laser diodes (laser pointers, CD / Blu-ray players)

- many quantum computers

Re: Semiconductors are more than just processors and GPUs

#22

Post by dragontamer »

babagabooj wrote: post #18
dragontamer wrote: post #17

Earlier quoted context omitted.

> Also, EPROMs are extremely vintage. They were replaced by EEPROMs - the first of which came out in 1977. That's an... extremely vintage example. IIRC, EPROMs were still cheaper than EEPROMs for many years. EPROMs probably were sold in commercial quantities well into the 80s, and maybe used in the 90s. EPROMs were erased by just throwing them into a UV-bin and blasting them with UV light. In contrast, EEPROMs needed…

True. I was there. So were you, I assume. The previous poster was most likely speculating.

Nah, I'm once removed.

I had professors who were active during the time and gave me the rundown. I have touched EPROMs and all that good stuff, still part of the labs at my college and my professor liked talking about "the good ol days". But I've never in fact used them in any practical manner.

Re: Semiconductors are more than just processors and GPUs

#23

Post by petschge »

deelowe wrote: post #20
blueflow wrote: post #2

Fun fact: Solar cells and the LEDs are the same element. If you wire up a solar cell like an LED, it glows dimly in infrared. QA uses this to diagnose dysfunctional wafers.

Many electronics work that way. Motors can also generate electricity. Inductors can create or sense magnetic fields. Resistance is generally temperature dependent. Etc.

Everything is as temperature sensor. Some elements also measure other signals.

Re: Semiconductors are more than just processors and GPUs

#24

Post by parenthesis »

deelowe wrote: post #20
blueflow wrote: post #2

Fun fact: Solar cells and the LEDs are the same element. If you wire up a solar cell like an LED, it glows dimly in infrared. QA uses this to diagnose dysfunctional wafers.

Many electronics work that way. Motors can also generate electricity. Inductors can create or sense magnetic fields. Resistance is generally temperature dependent. Etc.

You can use headphones as a microphone, or a (dynamic) microphone as a loudspeaker.

Re: Semiconductors are more than just processors and GPUs

#25

Post by thehappypm »

SECProto wrote: post #13
agumonkey wrote: post #4

Earlier quoted context omitted.

Is it possible to have a light / emw battery ?

Speed of light is fast, even if possible you'd be looking at a lot of conversion losses. It'd be like trying to use a wire as a battery because power has to travel from one end to the other

I’ve heard of materials that can slow down the speed of light propagation. Imagine you can slow the speed of light to a crawl. You shine a huge amount of light into this material, which has a mirror on the other side. Before your light arrives back at the source, swap it for a mirror. You’ve now got a huge amount of light energy trapped.

Re: Semiconductors are more than just processors and GPUs

#26

Post by _moof »

dragontamer wrote: post #16

Good overview, but he's missing one of the coolest applications of semiconductor / photolithography. MEMS. Micro-electromagnetic systems. The most common MEMS I can think of is the comb sensor, used for accelerometers in all of your cell phones. https://www.memsjournal.com/2010/12/motion-sensing-in-the-ip... The MEMS sensor for an accelerometer is quite simple. Take the nearest comb and smack it against a desk: you'l…

Microelectromechanical systems.

Re: Semiconductors are more than just processors and GPUs

#27

Post by analognoise »

babagabooj wrote: post #18
dragontamer wrote: post #17

Earlier quoted context omitted.

> Also, EPROMs are extremely vintage. They were replaced by EEPROMs - the first of which came out in 1977. That's an... extremely vintage example. IIRC, EPROMs were still cheaper than EEPROMs for many years. EPROMs probably were sold in commercial quantities well into the 80s, and maybe used in the 90s. EPROMs were erased by just throwing them into a UV-bin and blasting them with UV light. In contrast, EEPROMs needed…

True. I was there. So were you, I assume. The previous poster was most likely speculating.

No, I know they cost less for a while, but the 90's were 30 years ago.

That's vintage, isn't it? In the 90's, stuff from the 60's was 'vintage'. By 2022... the 90's are vintage?

Re: Semiconductors are more than just processors and GPUs

#28

Post by lb1lf »

dragontamer wrote: post #17
analognoise wrote: post #10

Earlier quoted context omitted.

That's not an EEPROM. That's an EPROM. The first E in EEPROM is ELECTRONIC - i.e. you use a voltage (or a control word) to indicate that you would like to erase the device. Also, EPROMs are extremely vintage. They were replaced by EEPROMs - the first of which came out in 1977. That's an... extremely vintage example.

> Also, EPROMs are extremely vintage. They were replaced by EEPROMs - the first of which came out in 1977. That's an... extremely vintage example. IIRC, EPROMs were still cheaper than EEPROMs for many years. EPROMs probably were sold in commercial quantities well into the 80s, and maybe used in the 90s. EPROMs were erased by just throwing them into a UV-bin and blasting them with UV light. In contrast, EEPROMs needed…

Studying EE in the late nineties, I can remember coming across EPROM microcontrollers a few times, but definitely not in new projects.

IIRC, students recently graduated when I was doing my freshman year had used them for projects in their freshman year, but not since - so they were probably commonplace until 1990 or so. At least in Trondheim, Norway.

Re: Semiconductors are more than just processors and GPUs

#29

Post by swamp40 »

I spent most of the day yesterday chasing down crosses for P-Channel FETs.

They are all GONE. No stock of anything (except the crappy ones, super-tiny packages, high Vgs(th) or high Rds(on) and other leftovers).

I've never seen anything like this, it's kind of frightening. Like walking into a grocery store and seeing the aisles all EMPTY except for a few scraps.

I don't even know where they all went. It's not like you need a TSMC slot to make a FET.

And whatever you look up, Chinese brokers have 10K-50K pieces of them for $25 each. Don't know what to think of that, either.

Re: Semiconductors are more than just processors and GPUs

#30

Post by AnimalMuppet »

analognoise wrote: post #27
babagabooj wrote: post #18

Earlier quoted context omitted.

True. I was there. So were you, I assume. The previous poster was most likely speculating.

No, I know they cost less for a while, but the 90's were 30 years ago. That's vintage, isn't it? In the 90's, stuff from the 60's was 'vintage'. By 2022... the 90's are vintage?

We look back on the 60s with nostalgia. The 90s? Not so much. I think that colors our definition of what is "vintage".
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