> I don't think any auxiliary equipment has been made for 1" wafers that is even remotely SOTA. 18" mask sets are at a million plus.
A slightly different opinion if I may.
For modern day litho (post 1990's), the field size is around 26mm x 32mm, so already larger than 1" diameter.
But you can use e-beam direct write on a small wafer chuck, which should get you to the 30nm node with ease, maybe even lower.
The problem lies most likely in handling and down the line processes.
As far as I am aware of, all masks are still 6", and the exposure field size 26x32mm.
This applies equally to all wafer sizes above 6".
The industry has been talking about 9" reticles since the late 1990's, but never took the punch.
And it will probably stay that way, now that we are approaching the physical limit of single exposure litho.
There are only a handful of people with 17" mask capabilities.
But they are not used for normal wafer lithography, rather for something else (which I should not tell).
Even 6" mask will cost well over 1M USD a set nowadays.
A more lucrative business than exposing small-lot wafers.
Patrick
A slightly different opinion if I may.
For modern day litho (post 1990's), the field size is around 26mm x 32mm, so already larger than 1" diameter.
But you can use e-beam direct write on a small wafer chuck, which should get you to the 30nm node with ease, maybe even lower.
The problem lies most likely in handling and down the line processes.
As far as I am aware of, all masks are still 6", and the exposure field size 26x32mm.
This applies equally to all wafer sizes above 6".
The industry has been talking about 9" reticles since the late 1990's, but never took the punch.
And it will probably stay that way, now that we are approaching the physical limit of single exposure litho.
There are only a handful of people with 17" mask capabilities.
But they are not used for normal wafer lithography, rather for something else (which I should not tell).
Even 6" mask will cost well over 1M USD a set nowadays.
A more lucrative business than exposing small-lot wafers.
Patrick
Surely you would have been beaten up if discovered by the cool kids who were listening to caroline?
And those were the days, eh Marce?
In my school (Quantock hills, Somerset) everybody had a transistor radio and we all ardently used them. Most were equipped with small earphone buds, so lights out didn't stop anybody. Simon Dee was very much "in", and everybody who was anybody never missed BBC's Thursday "Top of the Pops".
Despite all that, the headmaster was pleased to note that the generation which took its first O levels in 1968 was the best generation he ever had. And the Bee Gees played "Massachusets". 😀
In my school (Quantock hills, Somerset) everybody had a transistor radio and we all ardently used them. Most were equipped with small earphone buds, so lights out didn't stop anybody. Simon Dee was very much "in", and everybody who was anybody never missed BBC's Thursday "Top of the Pops".
Despite all that, the headmaster was pleased to note that the generation which took its first O levels in 1968 was the best generation he ever had. And the Bee Gees played "Massachusets". 😀
The question would be who didn't make a crystal radio, (Fox Hole radio) when you were a kid. I think I must have strung a 100' of copper wire across my yard as a kid for the antennae. War surplus headphones and all. If I remember it was in my Boy Scout manual.
Yes, the kids today really have to struggle, just making a choice between all that must be painful. 😀
The funny part of the current picture is that most of these kids, mine included. is that with all the technology they have most walk around listening to low quality compressed lossy MP3's with cheap junk ear buds. Not much better than the 9 transistor radios we had as kids.
Mine prefer to take over my system when they can.. But they do always have their music available all the time, a couple of mine are permanently plugged in... dawn till dusk music apart from when there is a film they want to watch.
I didn't let them near my system after they were little and thought they could put a CD on my turntable and you know what happened to the stylus after that! Didn't replace it for years until they got much older. Now they want me to build them some speakers. My daughter is interested in building her own equipment, I started her off on an 02 headphone amp.
Last edited:
Much to my dismay, my son (29) has zero interest in quality audio, despite the fact that I jave enough gear at had to put together a rather good system in a jiffy. I tried and tried, but to no avail.
As Kindhorman, said, kids today are perfectly happy with MP3 sound because to them, it's more important to stuff 1,000 songs on a memory stick than as to how it actually sounds. They settle for anything that's simply convenient, cheap and does not require them to switch their brains on.
As Kindhorman, said, kids today are perfectly happy with MP3 sound because to them, it's more important to stuff 1,000 songs on a memory stick than as to how it actually sounds. They settle for anything that's simply convenient, cheap and does not require them to switch their brains on.
I have to build some speakers for my lad, just no workshop since a recent move and all the heavy woodworking equipment sold...
I have found that most teenagers and young adults, when exposed to a reasonable system go wow, especially when they hear clean bass, the trouble is lack of income and places like Currys that use to sell separate's, don't, so the only places are the ever diminishing Hi-Fi shops... That most would find scary I should imagine.
It is up to the likes of us to encourage the next generation but with facts not magic.....
I have found that most teenagers and young adults, when exposed to a reasonable system go wow, especially when they hear clean bass, the trouble is lack of income and places like Currys that use to sell separate's, don't, so the only places are the ever diminishing Hi-Fi shops... That most would find scary I should imagine.
It is up to the likes of us to encourage the next generation but with facts not magic.....
That's what I said I don't know of any automated handling equipment for 1" wafers. Is there anyone doing one offs or research on 1", I don't know. We did buy a few of those JFET's used in particle detectors from those guys in Utah at $300 each as die. Someone like that maybe but I doubt it.
I avoid risking life and limb. This weekend one of our group was discussing the guy that jumped off cliffs with his little bat wings, he missed once.
Jimmy Webb spent a quarter of an hour telling me that he had to do the same as his father was a Baptist Minister pop music was strictly off limits!
So Marce, you are in good pop company!😀
354 here.
A friend of mine from high school had a higher number. The night they picked the lottery numbers, there was a radio broadcast. They did the first ten or fifteen birthdates live, then inexplicably cut away to some type of commentary, then came back to the calling out of the birthdates. As a result, once they got to 300 or so, if you hadn't heard your birthdate called, you were pretty much sure you were in that early, non-broadcast group, and thus soon to be in Vietnam and then, of course, dead.
When 354 came up, I was relieved. When 365 came up, and his birthdate had not been announced, my buddy was thinking of getting his affairs in order. Then they announced the final date, number 366, his birthdate. 🙂
The Wikipedia diode equations are giving me a positive voltage tempco which isn't right. Where are the right equations?
https://en.wikipedia.org/wiki/Diode#Shockley_diode_equation
https://en.wikipedia.org/wiki/Diode#Shockley_diode_equation
"The reverse saturation current, Is, is not constant for a given device, but varies with temperature; usually more significantly than VT, so that VD typically decreases as T increases." (from the Wiki cited)
Sze, Physics of Semiconductor Devices, presents material that can allow one to deduce the temperature dependence of Is.
There is as well a T^(3/2) term that is usually neglected. I found this to be significant at low temperatures for predicting cooled JFET drain-gate leakage, but it is confounded by other physics when the drain-gate voltage is high enough (sometimes as little as 4 volts!) to occasion impact ionization effects.
The bandgap energy is also slightly temperature-dependent, which makes silicon photodiodes have a shorter wavelength cutoff at low temperatures.
I don't remember 1", but back in the day on 2" wafers we were all issued with:
Attachments
I calculate one thousand, seven hundred, twenty six uA741 die on a 2 inch wafer.
This assumes the die size shown in the T.I. datasheet (45 milli-inches x 36 milli-inches), a wafer diameter of 50.0 mm (1968 milli-inches), and an exclusion zone of 81 milli-inches (45+36) around the perimeter. Estimation via rectal extraction.
_
- Status
- Not open for further replies.