iofiller cells are basically just small slices which are inserted inbetween IO cells to keep them connected (IO rings) together, if they are not abutted then you will have empty space inbetween the IO cells so you will need to put something there.
if i had well understoud so an IOFiller is a space in a IO cells in which we put a metal (any kind of metal) in order to make connection between other IO cells.
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thank you,
if i had well understoud so an IOFiller is a space in a IO cells in which we put a metal (any kind of metal) in order to make connection between other IO cells.
Not exactically.. it's a cell that includes the layers of metal for the IO power rings as well as any wells, substrate contacts, etc that should normally be present. So if you have cells that are spaced you put IOFILLER inbetween to electrically join the cells and avoid DRC errors, etc.