T he history of fab development has predominantly centered upon a single model:
a clean environment in which gowned personnel carry small containers of wafers from one process tool to another.
As wafers got bigger, fabs got cleaner .
Moore’s Law “ The amount of information storable on a given amount of silicon doubles every year.” Moore’s Law by Gordon Moore, 1964, founded Intel Technology since 1970 # of transistors per chip memory size Geometric features Technology since 1970 # of transistors per chip memory size Geometric features The Need for Speed increased exponentially decreased 1/2 every 18 months
Therefore risk of contamination, scratches, misprocessing, scrap and rework should be minimized. This is done through computer integrated manufacturing (CIM), standard mechanical interfaces (SMIF), minienvironments and AMHSs
300mm wafers are expensive, 10x more then 200mm
Impact: Automated material handling systems (AMHS)
Only 13 wafer lots can be hand carried. Due to human ergonomics.
Very high start rates, are required to make investments cost-effective. This would require a fleet of runners to carry production lots through the fab.
AMHS Height Considerations CLEANROOM Stocker OHT AGV/ RGV/ PGV Interbay Transport Zone Overhead Intrabay Zone Process Tool Ceiling Raised Floor 6.83M 3.5M 3.5M <1.8M 0.9M 3.7M Stocker Tool Move-in ( 2.2m X 2.8m ) Operator I/O Operator I/O Optional Local Tool Buffer Optional Intrabay I/O FFU Truss 7.5M min 7.25M Waffle Slab
SubFab With the introduction of larger wafers, comes the problem of re-tooling . Larger and more sophisticated tools are required. More support equipment is needed. Larger tool and support equipment footprints that need more space . Does this mean; Bigger Fabs and sub-fabs? Impact: Tool Footprint
Space Management WAFFLE SLAB RAISED ACCESS FLOORING SINGLE SUB-FAB Impact: Utilities
Space Management DOUBLE SUB-FAB WAFFLE SLAB RAISED ACCESS FLOORING