wdcox@voder.UUCP (Bill Cox) (01/22/87)
Does out there know about new wafer scale integration research? It seems to me that it just would not be so hard to make an arbitrary permutation interconnection type computer that would allow at least 128 good dies to be switched into a hypercube-like network on a single CMOS wafer. A simple two address risk processor with a small local ram should easily run at 20 to 40 MIPS if it were an accumulator machine, so the processing power could be astounding. The wafer should be about the most reliable thing around, because new processors could be switched into the network after a processor dies. The switching network itself would also be very reliable... IBM has researched the idea of reliable arbitrary permutation networks and came up with a beautiful solution, although it is designed only to work if 32 out of 33 chips work in each of two rows of chips. I think it could be modified to work with die yields of only 50% in the interconnection dies. If there is a simple solution to the heating problem, like gluing the wafer to a water-cooled block of some type of ceramic, and using a muffin fan to cool the water, then it seems like the whole thing would fit into something the size of an Apple II computer. Its frustrating to work at a company that probably could manufacture such wafers, but is to inflexible to think about such ideas. Is there any kind of research of this sort going on somewhere else? Bill Cox ucbvax!voder!wdcox National Semiconductor
billw@navajo.UUCP (01/31/87)
Several heavilly funded companies (eg Trilogy) have attempted to do wafer scale integration, and failed due to technical problems. It isn't easy - remember that your "arbitrary interconnect" to connect the good processor dies has to have its own redundancy, and that for large N, interconnects are more complicated than processors anyway. There was an artical in Electronics or digital design or some such reporting on one of the few companies left, who have succedded in making memory chips out of large pieces of wafers - unfortunately, the total capacity is less than some memory chips produced by more conventional means. BillW