xSection: lift-off process

Negative values for the lateral component in etch() don't work. It produces non-sensical shapes, missing material. I wanted to visualize a lift-off resist process but got stuck there. I was able to piece it together by etching the layer.inverted with a positive angle, and the fill it with material. It does have a negative sidewall angle in the end, but maybe this could be updated ?

Besides that, there is no option in deposit() or grow() that would emulate a line-of-sight evaporation. Growing on a material with an overhang always deposits on its backside. I can set the lateral component to zero, but the overhang has a normal component to it that I cannot seem to get to forbid to grow on. Am I missing something here ? Maybe I am doing it all wrong and there is some other way niftier way ...

If not, can I request this to be considered for implementation into the next version ? It could literally be called evap(), the only difference to grow() and deposit() is that it would deposit/grow on surfaces that are at the interface to air (as normal), but not where there is material above it (with an airgap). Maybe "angle" could be an input variable ?

Thank you !!



  • Hi Thomas,

    the cross section script is very limited unfortunately. It is based on very simply geometrical operations and "line of sight" is definitely beyond the capabilities of this scheme.

    I feel the current version is already exploring the very limits of this approach. I think that for advanced features new core algorithms will be required.

    I'd also like to point out that xsection is a community project. Everyone's invited to contribute: https://github.com/klayoutmatthias/xsection

    Just drop me a pull request.


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