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Best way to bond laser diode materials together

  1. Dec 29, 2018 #1
    chemical vapor deposition, Molecular beam epitaxy or magnetron sputtering

    What is the best way to bond GaAs to the intrinsic layer of a laser diode? I am planning on building a refactory oven on a concrete pad this summer once I clear of one side of my yard. There is just no way around it, everything I want to do involves super high heat whether its melting glass in a platinum coated mold for optics or bonding GaAs, etc.

    But what is the best way of accomplishing this, it seems the oven is the same its just whether you allow multiple holes to connect a vacuum pump or have a rotating tray or the ability to hang the substrate upside down, etc.

    Magnetron sputtering is probably the easiest and I already have all the parts for it I just need more indoor work space.

    I found this super high heat cement that can be poured into what ever shape I want and then just layer the bottom in fire brick to protect the concrete pad as much as possible - https://www.sheffield-pottery.com/LO...AR-p/lvclc.htm

    And these heating elements which seem to be a good deal and would allow for close temperature control by regulating current - https://molybdenum-cn.en.made-in-chi...t-Furnace.html

    Do they have special valves that are super thermal insulators to keep tons of heat from escaping from the vacuum ports? If I can just sputter the GaAs right onto the substrate that would be great but typically the GaAs IS the substrate ...
  2. jcsd
  3. Jan 8, 2019 #2
    From the general feeling if your post, you are likely not ready for construction.
    GaAs lasers production is very complicated and generally not compatible with the backyard facilities. Liquid-based process of GaN tech is more scaleable for small facilities though.

    Some specifics you likely missing:
    1) Magnetron sputtering chamber need 2 liquid cooling loops - separate for target and substrate. Failing to do so will result in under-performing of dysfunctional chamber. Also you need to plan cleaning procedures beforehand - failure to make cleanable sputtering chamber is quite common.
    2) Thermocompression bonding machine require significant pressure delivered by hydraulic jack with liquid cooling loop. Pressures and temperatures involved mean typically stainless steel construction and cartridge heaters close to substrate (with steatite thermal insulators before heat-sensitive parts), not the refractory brick/mold or convection/IR heaters.
    3) Heat escape through vacuum manifold is usually negligible. Semi-rigid (bendable) metal pipes in meander shape are typically used to reduce issues with heat conduction and thermal expansion.
    Last edited: Jan 8, 2019
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