Shuttle Mask Floorplanning
With the dramatic increase in mask production cost, it is
difficult for small and medium-size enterprisers to do effective
prototyping and low-volume manufacturing of IC designs. Multi
Project Wafer(MPW) is an efficient method to share the mask cost
between different projects. Designs from multiple customers can be put
on one single mask substrate, called shuttle mask, to produce a MPW.
We have studied this problem of shuttle mask floorplanning.
Unlike traditional floorplanning, we need to consider the
side-to-side wafer dicing constraint of the diamond sawing
technology. We consider
grid packing in this research as the side-to-side dicing constraint
can be easily taken care of by cutting along the grid lines and no
dies will be destroyed. We have defined a special type of grid,
called modified &alpha-restricted grid, to reduce the size of the
solution space. Besides, the &alpha-restricted grid
structure is good for controlling the white space margin of the
diced chips. Chips of the same design will have the same margin
lying within a range given by the users. In the future, we
will consider more information like the demands of different
designs, the costs of wafer and mask, etc.
- RGC Earmarked Grant on "Shuttle Mask Floorplanning" (2006-08)