patwillson22

ayy man, you crossed zucc, you get the buck.

I think people underestimate the gains that new technology will have for aiding our ability to see neighboring galaxies and exoplanets. For instance, our interpretation of spectral data is limited by both technological limitations (lasers can only probe certain wavelengths) and also theoretical ones. We also cannot accurately determine what happens in light matter interactions. Thus, the signal to noise ratio is so high that our current instruments have little chance of finding definitive evidence for life. This could change rather quickly though, the james webb telescope is one example, it is equipped with CCD that can "see" light in the infrared spectrum.

My advice to anyone who's looking for a pathway into open source silicon is to look into E-Beam lithography. Effectively E-Beam lithography involves using a scanning electron microscope to expose a resist on silicon. This process is normally considered to slow for industrial production but it's simplicity and size make it ideal for prototyping and photo mask production.

The simplistic explanation for why this works is that electron beams can be easily focused using magnetic lenses into a beam that reaches the nano meter level.

These beams can then be deflected and controlled electronically which is what makes it possible to effectively make a cpu from a cad file.

Furthermore, It's very easy to see how the complexity of photolithography goes up exponentially as we scale down.

Therefore I believe it makes sense to abandon the concept of photolithography entirely if we want open souce silicon. I believe that this approach offers something similar to the sort of economics that enable 3D printers to become localized centers of automated manufacturing.

I should also mention that commercial E-beam machines are pretty expensive (something like 1-Mil) but that I dont think it would be that difficult to engineer one for a mere fraction of that price.

I'm a junior in college and hoping I'm can get a prototype out before the end of the summer.

I've worked with other PVD systems yet I have not constructed my own. The main goal of this system is to make this sort of thing accessible to as many people as possible for the lowest amount of cost.

As it stands right now I'm learning machining to actually build most of this thing from scratch as I don't have the money to get this machined from from a job shop.

You could, I've seen a couple of papers attempt that approach with rather poor results something like 8-10% percent. Though I'd say by the easiest approach to producing thin films cells involves basically using electroplating which achieves similar efficiency (https://onlinelibrary.wiley.com/doi/abs/10.1002/pip.417).

The cycle time is of course a highly dependent on the final design of chamber. There's no reason that Sorption and Getter Pumps combined with a ventri prestage can't preform to a degree that meets the design requirements.

However their performance is highly dependent on two things, the ability to reach bakeout quickly and the use of metal to metal seals instead of o-rings.

The actually difficult and expensive part of high vacuum engineering is figuring out how to engineer valves that can both withstand bakeout temperatures and make the tight leak free seals.

In this regard I plan to use what essential amounts to a plate valve with something called, a "powdered seal". This valve meets the requirements for the design in every aspect with it's only downside being that it is slow to change open to close. Though this downside will not reduce the overall throughput of the system as it is designed.

Alright here it goes.

What we're basically doing is using thermal evaporation to lay down thin films of metal on top of each other in a high vacuum environment. We're then patterning the cell with a fiber laser to produce the cell traces and patterns needed to cell size.

Here's an example of system that does what i've just described in the context of creating CDTE cells. Note that it doesn't use a laser to create the cell divisions but rather uses a conductive ink and sand blasting.

https://avs.scitation.org/doi/abs/10.1116/1.4941071?journalC....

I thoroughly analyzed their design and I have copied some aspects of their design while avoiding many of the flaws that significantly limited it's practically and efficiency. Here's a quick summary of the design changes and flaws that I found.

For one, the design specified in the paper can barely reach high vacuum which is a requirement for producing cells of reasonable efficiency.

One major improvement I'm working on is a system that allows for automatic changing depostion powder inside that chamber instead having multiple chambers for each layer of depostion powder.

The advantage of this approach is that miniaturizes the chamber size significantly, making closer to the size of something that could fit in the back of your car then something that needs a dedicated room or floor for.

I've also looked carefully at how im going to achieve high and maybe even ultra high vacuum. And in that regard I think I've made some significant strides.

My design achieves high vacuum in three stages, the first is through a simple ventri pump and the second is a sorption pump which has been redesigned based on a old paper I found here(). The last stage uses something called a non-evaporable getter pump.

Experienced vacuum engineers might initially be baffled of choice of pumps I am using. As they are normally considered too slow for the type of operation that the chamber is being put through.

However, the downsides of the speed of these pumps can be mitigated by three measures. (1)Building a chamber that can go through bakeout(which removes contaminates and reduces pump down time) (2)Designing a chamber with metal-to metal seals and low leak rate. Lastly the obvious principal of making the chamber volume and surface as small as possible while making the size of the pumps large.

I've barely scratched the surface here but I think this should give you a rough idea of what I'm doing. I really dont think this stuff is hard as how it's made out to be.

Here some resources that really have really helped out so far.

-Building Scientific Apparatus a book that should give you a broad overview of things you need to know

-vacuum sealing techniques alexander roth Extremely exhaustive in the amount of information of about, valves, and just general construction of the chamber. The book is really old but everything still stands and it's honestly better than most of the stuff i've found online.

Blogs by this guy https://www.normandale.edu/departments/stem-and-education/va....

Really good introduction to basic stuff you need to know and decisions you need to make.

If anyone has any questions further I would be happy to answer them.

I'm working on an fully open source Physical Vapor Deposition System which is capable of producing thin flim solar cells, Ex(CIGS,CDTE) at efficiencies in the range of 15- 20%. The system is designed to produce one 10 watt cell for every 45 minutes. I could go into further depth here but for obvious reasons It would take me a while to explain everything.

Clearly this is a CIA plot. I know people who work in JPMorgan and they have shown me APIs specifically designed to detect deep web bitcoin purchases. Let's just say that there's no such thing as privacy anymore.

I dunno man, sounds like bullshit to me. Some big brained engineers spent decades programming fizz buzz in brain fuck. This is temple OS for the We Work Generation.

The road to hell is paved with best practices.

this is what happens when trumpism/lead poisoning combines with the worst elements of dutch racism towards to Germans. What's more is that this fence is unlikely to serve it's intended purpose, this is because german pigs, much like their human counterparts are simply too large to be hindered by a simple 1.5 meter fence. I hope that for the sake of western civilization that the dutch will halt their plans to build a wall and settle for less draconian polices.