Second megabit chip

Press, 3 February 1987, Page 23

Second megabit chip

One-million-bit . chip technology with packaging and design enhancements result in dramatic performance enhancements and increased storage capacity in the new IBM 3090 processors just announced.

This marks the second time in less than a year that IBM has announced a one-million-bit chip for use in the 3090. In April, 1986, IBM became the first company to use meegabit technology in mainframe computers being shipped to customers.

The 3090 models use a one megabit memory chip that operates almost twice as fast and occupies about a third less space than the original IBM one-million-bit chip. The high-speed chip is the fastest Dynamic Random Access Memory (DRAM) chip used in central storage in any commercially available mainframe computer system. The chip takes only 80 nanoseconds (billionths of a second) to access data stored. At that speed, coupled with its fastest rate of data flow, this single chip could “read” a 2200-page document in one second. The IBM developed and manufactured chip measures 5.5 mm by 10.5 mm (7/32 inch by % inch). It is fabricated in a process that produces geometric features such as line widths as small as one micrometer. To increase the manufacturing productivity of the new chip, IBM is phasing in production using 200 mm diameter silicon wafers. These wafers — the largest in production anywhere — can hold about three times as. many chips as the 125 mm wafers they succeed.