The cone of Cherenkov radiation produces arcs of "bright pixels" in the detector.
There are very good illustrations of this if you search for "Super-Kamiokande Cherenkov ring." That's a Japanese neutrino telescope with a bunch of huge photomultipliers lining the walls of a giant underground cistern filled with water. Ice Cube has similar light detectors, probably from the same Japanese manufacturer, that were lowered on strings into wells melted into ice.
It was not just the VCs. There were also influential people in Pentagon who saw the inefficiency of the prime defense contractors, especially after having seen what SpaceX was able to do.
One of the consequences of this was the meteoric rise of the young Will Roper [1], who in a span of a few years went from a theoretical physicist to being in charge of the Air Force procurement program, and then tried to facilitate the access of startups to defense contracts, through AFWERX and "Defense Pitch Days".
Whether this worked or not is debatable, but the itch to change things was there. One example of a startup which was an early beneficiary of this top-down attention is Ursa Major [2], a rocket engine company. Unless one looks at them in the context of these military programs, their existence would seem quite puzzling.
"This project is a collaboration with Miles Segal (Gotham Silicon), whose mission is to make microchip fabrication more broadly accessible. Creating ultra high resolution micron-scale imagery is the very first step in this process."
"Those are clips of Miles in the Columbia University Nano-fabrication Facility where he is developing a workflow to make the technology required to build microchips more accessible."
"Miles Segal is building an ASIC foundry by repurposing vintage nano-fab gear to deliver custom chips in 24–48 hours."
"During the week he was at @EdgeEsmeralda, he focused on making new connections – leaving with new energy, confidence, and momentum from countless serendipitous convos."
So it seems to be one very young dude passionate about revolutionizing semiconductor processing. Whether there is an actual market for a super fast turnaround at 1 um node, and whether he has the experience and the support to pull this off, is somewhat dubious.
But of course wonderful things do sometimes happen. While he was a student, Sam Zeloof became a legend by building a chip fabrication lab in his garage, using surplus and home-made equipment. Now he has a serious team, working on developing mini-fabs: https://fab2.com/ That looks pretty serious.
Sounds great as a slogan, but there are no details. For comparison, Intel's 1 um process (Fab 3, 80386-era) required about 4 weeks of processing time, and if pushed, the samples could be processed in as little as two weeks. For a long time they were getting about one working die per 4" wafer.
Yes, only one day of processing is impossible for any kind of integrated circuit.
One day of processing would be possible only for semi-custom integrated circuits, like gate arrays, which have already been fabricated until a last step that only adds one or two custom metal layers to interconnect the existing components and then separates and packages the devices.
Even with that, one day of processing would be possible only for making a small number of chips, where the metal layers would be patterned without masks, by direct exposure of the photoresist with a laser projector. Making photolithography masks would take more than one day.
Short turnaround times does not mean a single day.
Even an ancient 1 micron CMOS process requires something like one hundred process steps, many of which may need up to a few hours in an oven. If completely automatized, it could be done in a week for small batches, but not in a day.
One day could be achieved only for semi-custom integrated circuits, where the customer only specifies the interconnection of the components existing on the pre-processed chip.
Decades ago, when unlike today, there were a very great number of integrated circuit producers, there were many who offered a set of IC dies from which to choose one, where each variant could have different sizes, while including various mixtures of digital gates and analog components like amplifiers, comparators, voltage references etc., and after choosing one of the available base dies the customer would specify only how to interconnect the components and how to bond the die to the package pads.
With such semi-custom integrated circuits, it would be possible to complete their fabrication process in a day, by using direct exposure, instead of masks, for the final metal layers.
At the 1 micron level, the photoresist can be patterned directly with a laser projector. There is no need for an electron-beam machine, like for nanometer-resolution lithography.
Yes, Yes. I know. Because of that I said 'something similar'. Yokogawa/Minimal.fab themselves say different things for different chips, up to one week, but also one day.
That depends on the used substrate, they don't only have the ones which are in common use. They also don't need masks for anything, and their wafers are small. It's all a little hard to get, and the most current information is their Japanese site, with translation.
Have you looked deeper at theirs, or 'similar' stuff? I think it's misleading trying to extrapolate from an ancient process to this, 'or similar', because the roads taken by the mainstream(machinery and processing) do not necessarily apply to other roads, which others may have taken. And I don't mean by circumventing physics. Just applying them differently. For different volumes and scales.
To skip the use of masks, there exists only 2 possibilities.
For low resolutions, down to around the 1 micrometer claimed in the linked site, it is possible to use a small and low cost laser projector, which is also quite fast.
For higher resolutions, an electron-beam machine is needed, which works in a vacuum chamber, and which is big, expensive and slow (the slowness is not actually due to the electron beam, but to the fact that a chip that must be made with high resolution lithography would have many more components in the same area than a chip that can be made with low resolution lithography).
An electron-machine would be bigger by itself than what Yokogawa shows as being a "Minimal Fab", so I assume that Yokogawa uses a laser projector.
I could not find any statement about which is their best achievable resolution, but they give an example of a circuit made with 4 micrometer gate length, so I assume that their best resolution might be around 1 micrometer, which is compatible with a laser projector.
Yokogawa gives their processing time at one week, for a fabrication process with 98 steps, which is very close to what I have estimated in another posting here.
Actually, I think that the company whose site is linked in this thread might have just bought some equipment from Yokogawa, as that could match their claims.
Nonetheless, a one-day processing remains compatible only with semi-custom chips, where the customer just interconnects the pre-existing components, not with a fully custom chip.
Moreover, the Yokogawa equipment uses tiny wafers, where the maximum die size is limited to about 8 by 8 millimeters, and at that size you would get 1 die per wafer, with great chances that it may be a bad one, or if you make small 2 by 2 mm dies, you get just 16 per wafer, from which a dozen might be good, and so on.
So you must need only a small number of dies, otherwise the fabrication could take forever. Nonetheless, even such a small number of dies could be good enough for prototypes or for the needs of small businesses or individuals.
I certainly would like to order such integrated circuits, but for this the vendor would have first to publish the technical documentation with the characterization of the semiconductor devices that can be made with their fabrication process, to enable the customer to do simulations of their designs, before submitting one for fabrication.
A one-micron resolution is intermediate between that used for the Intel 80386 processors and Intel 80486 processors, but closer to the latter.
So it would certainly be good enough to make various custom circuits, which could substitute the standard microcontrollers or FPGAs together with any needed auxiliary ICs, where MCUs and FPGAs typically must include at least an order of magnitude more internal resources than are used in any single project, in order to enable their use in any of those projects, so a dedicated chip can be made much simpler and more energy-efficient.
I would argue that the primary use for this type of prototyping is to test analog chip designs, because analog components don't scale down that well. Digital information only needs to distinguish between 0 and 1 but with analog electronics the maximum current or voltage you support grows as you use a bigger area or thicker layers.
I personally don't believe that even a $100 service delivering you 1 micron chips could compete against a $10 FPGA unless you are intentionally doing something the FPGA was not designed for like analog electronics or low static power.
I partially agree with you, in the sense that any useful custom integrated circuit must include some analog part, otherwise it would not be competitive with standard programmable logic.
Nonetheless, having actually worked as an analog IC designer, I can assure you that today, and especially when using a CMOS IC process, where the analog devices that are available, like MOSFETs, are inferior to the bipolar junction transistors and junction FETs, which were available in the fabrication processes traditionally used for analog ICs, it is completely impossible to make a competitive analog circuit that is purely analog.
Any CMOS analog circuit needs a digital part, even if it is something as simple as an amplifier, and more so for things like a power supply or a motor controller, or something that acquires data from analog sensors.
At the minimum, a digital automaton together with a lot of configuration switches is needed to perform the auto-calibration of the analog parts when the IC is powered on. Otherwise, things like differential amplifiers would be unbalanced, bias current sources and amplifier gains would have values very different from those needed for the circuits to work as designed, etc.
Digital parts may also implement in a simpler or more reliable way various kinds of control feedback loops and various protections to undesirable conditions, e.g. overcurrents, overvoltages etc.
So any useful custom CMOS circuit must be a mixed digital-analog design, i.e. it must include both a digital part, with flip-flops, digital gates and switches, and an analog part, with amplifiers, comparators, analog multiplexers, oscillators, voltage references, etc.
An one-micron CMOS process would be especially useful if its component list would include some NMOS transistors with a higher breakdown voltage, of at least 12 V, but preferably even of 20 V, or ideally of 25 V (to have a safety factor if using an 18 V power supply, as required by the gate drivers of some power MOSFETs).
An one-micron CMOS IC would likely use 3.3 V for the main power supply, and it should be able to use 5 V at least for I/O buffers. But if some transistors with a higher breakdown voltage would also be available, they could be used for open-drain output buffers that would be tied to an external higher voltage and they could be used to command directly some external power MOSFETs, without an intermediate gate driver. A standard 5 V I/O buffer could command directly an external GaN HEMT (gallium nitride switching transistor), but presumably the output current of the buffer would be low, so the switching of the external transistor would be slow in comparison with using an additional gate driver IC.
I don't have the impression that a $10 FPGA can implement the equivalent of an 80386. I can believe it of a $1000 FPGA. I don't know what the right intermediate point would be. But big FPGA's are very expensive, mostly because the customers for such things are well funded.
If Isar will get a large scale commitment from the government(s) to launch the OneWeb 2.0 constellation, as the European alternative to US, Chinese and Russian systems, they may well become a major launch provider. And of course they are already working on a much larger reusable rocket.
Although the original OneWeb satellites were assembled in the USA, they were developed in Europe and the components were always sourced predominantly from Europe, Canada, and Africa, with only some parts produced by the European companies in the USA, and even fewer parts sourced from the US companies. It is a very European satellite.
Incidentally, the early investment for Isar came from Bülent Altan, the Turkish ex-SpaceX guy who was in charge of the guidance system for Falcon-1, Falcon-9 and Dragon.
Most of the US space launch startups have failed. And in Europe it is harder to even try.
There was a confluence of several factors which helped SpaceX to succeed, and not the least of these was the employee number one. For many years, Tom Mueller has been working in his free time on rather large liquid fuel amateur rockets, which he was building in his garage and which he was launching from some amateur rocketry facilities in the desert. In terms of regulation it was a relatively accessible hobby in the US. At the time Musk found him, he was working on the original "BFR" -- a very large liquid fuel amateur rocket. So the deal was to invest serious money into the project and scale the same no nonsense approach to a small orbital launch vehicle. They were in LA, the center of US aerospace manufacturing, so through Tom's professional connections and knowledge of who was who in the industry, they were able to source the necessary materials, components, and to find the key personnel for their company. Significantly, NASA has already spent probably a decade or more trying to get somebody to produce a cheap small launch vehicle. This did not directly affect SpaceX, but it did fund the R&D for example at Barber-Nichols, which enabled them to offer a turbopump for SpaceX engine at a much lower cost than it would have been possible otherwise.
At first, Musk and Co thought that they would be able to develop the rocket for a few million dollars. But even in the US regulatory environment it turned out that doing everything in compliance with regulations raised the costs to well over a hundred million dollars.
So, Tom's hobby + Musk's activism + industrial ecosystem in the area + NASA's prior support of component vendors + being at the right time to snag the International Space Station delivery contract were all important for SpaceX thriving where so many others have failed.
USA got the cream of the crop of the managers of the German missile program, while the USSR got the workers, who actually did the work with their hands and built the parts for the rockets. (One exception was Helmut Gröttrup, the head of the V-2’s guidance and telemetry systems.)
In fact, after the war the USSR has briefly reconstituted the manufacturing of V-2 in Germany, employing thousands of people, before transplanting this entire industry to the USSR. This dramatically lifted the level of Soviet manufacturing and relevant metallurgy.
von Braun's dissertation was on engine design and testing. But when he built the Redstone missile in the USA, he ordered the engine from a US company -- the engine which was already a generation ahead, compared to the imported German engines which the US engineers studied after the war.
Meanwhile, the Soviets have developed even better engines, completely on their own, though with the important parts built using the materials and the equipment brought from Germany.
So it is debatable whether having the German higher-ups and having a greater continuity with German design philosophy was a good thing or a liability.
It is less well known, but France have also imported a significant number of ex-Peenemunde engineers for their program. And their engines developed in a way different from both the American ones and the Soviet ones -- which definitively shows that although internalizing the German know-how was the starting point for everyone, it did not define the path of subsequent development.
Of course, the engines were not the whole story. The Germans took to the USA the advanced prototypes of the inertial guidance systems which were developed for the missiles that were supposed to come after the V-2. And the Soviets got Helmut Gröttrup. This did have its effects in both cases.
great comment, just wanted to add a little: all three countries were pioneering rocketry in the 20-30s, more or less in equal measure.
I don't know why this WW2 rocket discussion happened to begin with, but people here don't seem to understand that there is no magical inherent technical skill which is unique and irreplaceable. Experience helps to speed things up, sure, but it can be acquired by any program given time and resources, with no talent blockers.
> USA got the cream of the crop of the managers of the German missile program, while the USSR got the workers
That's a bit oversimplified. The Russians got quite a few important scientists and engineers in other areas (aircraft design, nuclear physics, electronics, radar, optics), they just didn't make as good use of them as the US (e.g. the 'American Germans' essentially won the space race for the US).
Talking about the role of V2 in the development of rocketry in various countries is more or less relevant to the discussion of Isar, because it was a major milestone, and it did influence all rocketry worldwide, in many different ways.
Rocketry may be much more talked about, but in terms of headcount is was a tiny thing compared to the number of German experts who were "invited" into all Allied countries after the war. Just France and UK had brought in about 3 thousand persons each. If one had said that this did not happen, that would have been an error. But simply not bringing this up at all because it is not very relevant to the discussion of Isar is fine, I think.
Debating who "won" the space race, and who "used" Germans "better" is not something that I want to do.
They do not like to talk about it too much in public these days, but Rocket Lab had somewhat shady beginnings. Once they moved past the semi-amateur phase, their first real project was weapons development on a DARPA contract. They were working on a paste-like semi-solid fuel for throttleable engines for munitions, and other similar things.
That pushed their main NZ investor away, and they somehow hooked up with the US intelligence community, which facilitated a rather unique series of inter-government arrangements for launching US reconnaissance satellites from NZ. That was probably always the appeal -- to launch over China with very little warning. A cheap, rapidly launchable vehicle was always a dream of the US agencies -- in 2003 this was FALCON program (Force Application and Launch from CONUS) run by DARPA and the Air Force, and today it is the Space Force's "Victus".
So, although the bulk of work was done in NZ, Rocket Lab functioned rather intimately with the US spooks from the very early on, including getting some funding from In-Q-Tel. Then in 2013, for the bulk of investment they just had to become a Delaware Corporation, for all the usual reasons. Very soon they moved engine manufacturing to a facility in California. More recently, with the large rocket (Neutron), their main manufacturing operations are in LA and the launch facility in Wallops. All in all, they are an international outfit.
It is uncontroversial among Dostoyevsky's scholars that his main focus is on Russian mysticism while the stories themselves are merely a setting for presenting author's theology. But that may be flying over the head of a typical Western reader. Even for Russian schoolchildren this requires to be carefully explained.
Dostoyevsky subtly advocates that Western rationalism, materialism, and utopian socialism lead to failure, and only spiritual communion of people bound together by love and Orthodox faith can give hope. This idea of specialness of "messianic Russian soul" and of Orthodoxy is extremely in vogue today in modern Russian ideology. But that is a different subject.
There are very good illustrations of this if you search for "Super-Kamiokande Cherenkov ring." That's a Japanese neutrino telescope with a bunch of huge photomultipliers lining the walls of a giant underground cistern filled with water. Ice Cube has similar light detectors, probably from the same Japanese manufacturer, that were lowered on strings into wells melted into ice.
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