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Thread: Molecular Beam Epitaxy and Effusion cells

  1. #1
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    Default Molecular Beam Epitaxy and Effusion cells

    Does anyone have any good references on the construction of Effusion cells and RHEED/Electron guns. Is it better to use MOSi2 or Ta for the heating element in the Effusion cell?

    Do the components in the cermaic crucible of the Effusion cell vaporize more readily due to the fact that a vacuum is pulled on the entire system?

    From what I have read this is the most efficient method of depositing things like Ga As Al B P etc.

    It looks like in some designs the vaporized metal is assisted by oxygen, i am guessing this would require the vacuum pump to be on full time, does the hot gases cause issues with the internals of the pump or vaporize the pump oil?

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    I dont know how I have garnered such hatred on here by wanting to build a laser. It really is crazy.

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    Not hatred ... indifference. It's not that you "want to build a laser". It's that you want to reinvent the wheel, and for a stated reason that doesn't sit well with those who are heavily invested in the safe and legal use of laser light. This is a forum related to the laser application of entertainment. Light shows, projectors, and visible lasers applied to those. Those at LPF are into handheld lasers for their personal entertainment, assembled from off-the-shelf parts and those harvested from other devices. You're simply in the wrong place if you want to do as you say. I'd recommend physics and engineering forums, after obtaining a masters or PhD and some years in the industry. Just sayin'.

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    I don't hate you at all. I love the enthusiasm. Channel it into something a little more approachable. Show me one successful project and I'll hang on your every word.
    Start off building a successful vacuum system with a turbo pump. That is the basis for this. Next build a mass spectrometer. or electron microscope That is the next part of it.
    Here are some starting points.

    https://www.youtube.com/watch?v=-v-plpSI3lY
    https://www.youtube.com/watch?v=9iR4uk3gauU
    https://www.youtube.com/watch?v=NZK7RBcdkT8
    https://www.youtube.com/watch?v=6mDQ_AmiUbk
    https://www.youtube.com/watch?v=x_l1U7ZV8dI this one is impressive! a dorm room!
    https://www.youtube.com/watch?v=9OEz_e9C4KM

    have fun

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    That is fair ...

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    Does anyone know of any engineering or science forums where I could ask such questions?

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    Quote Originally Posted by akmetal View Post
    Does anyone know of any engineering or science forums where I could ask such questions?
    If you are really going to do this may I suggest you find a local university or company that does this and see if you can visit or volunteer.

    i still say build the vacuum system. You need it for nearly everything anyway. There is a YouTube video of a woman that made her own transistors. They were not good one but they worked and it didnít involve anything all that special. The name escapes me but look up circuit girl. The other person who may help you is the guy from YouTube channel applied science. He may even want to join you to do it.

    i think you need to find a flesh and bones mentor at this point.

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    mixedgas is offline Creaky Old Award Winning Bastard Technologist
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    Jerri Ellsworth is the Girl..
    ~
    You might just find one of her laser related videos where she credits me for the help and the initial idea at the end, if you knew my first name. I use my Middle name..
    Really fun lady to talk to...
    Steve
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

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    Quote Originally Posted by mixedgas View Post
    Jerri Ellsworth is the Girl..
    ~
    You might just find one of her laser related videos where she credits me for the help and the initial idea at the end, if you knew my first name. I use my Middle name..
    Really fun lady to talk to...
    Steve
    Sounds perfect, thank you. My night time reading is the books you recommended.

    I have abandoned the epitaxy route and incorporated the Nd yag into my existing laser design and will just change the gas to krypton to supply the energy to the Nd yag crystal.

    Although high vacuum is still of interest for particle acceleration.

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    Quote Originally Posted by akmetal View Post
    Sounds perfect, thank you. My night time reading is the books you recommended.

    I have abandoned the epitaxy route and incorporated the Nd yag into my existing laser design and will just change the gas to krypton to supply the energy to the Nd yag crystal.

    Although high vacuum is still of interest for particle acceleration.
    Can you explain how you change the gas to krypton in a ndyag laser? Are you pumping the rod with a flashlamp? This makes no sense to me otherwise. Xenon is more commonly used. Flash lamps are really approachable but be ready for a lot of failures and a few loud bangS.

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