It really doesn't make any sense to say what shape are electrons or photons. It also makes no sense to talk about a photons or an electrons in a particle form.
These are quantum objects and they cannot be described accurately using classical ideas. Quantum objects are not part particle and part wave nor are they sometimes particles and sometimes waves, they are objects that have 'particle like' and 'wave like' attributes.
There is already a simple idea for the interference pattern from the double slit experiment.