table – Is it possible to force the Spacings in Grid to actually be 0?

I am trying to use Grid[] with Spacings->{0,0} but the distance between the items doens’t actually get $0$. It becomes something like:

enter image description here

Is it possible to actually for the distance to be 0?

Add: Something that could also help me, given a string, say "a" can we make Mathematica treat it as image?