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In the world of nonvolatile memories, capacities are doubling annually, costs and access times continue to fall, and the use of CMOS technology is increasing. The nonvolatile memory is unique because it retains contents even during power shutdown, a feature that offers distinct advantages over other types of memory. Tighter design rules, circuit innovations, and improved lithography are teaming together to reduce delays inside the chips. The industry is anxiously awaiting the 512k EPROM, with the thought that a 1-mbit EPROM is not far away. A graph is included that portrays bit density vs. year.

Dennis Derfiny, a section manager for Motorola Inc. Systems Division, warns that as speed increases to the point required for high-frequency communications, passive components become electrically active. Surface-mounted components will not only improve density and reliability, they will reduce propagation delays and spurious noise emissions at or past gigahertz frequencies. This is understood by most microwave engineers, but is still newsworthy for telecommunications people.

The PAL 32R16, developed by Monolithic Memories, is the equivalent of 1600 gates and operates at eighteen MHz. Based on the novel product-term sharing technique, the active state of PAL 32R16 may be programmed low or high. The TTL-compatible 32R16 is listed at $50 each in lots of 100. A photograph is shown.

Magnetic-bubble memory chips holding 1-Mbits could pose serious competition to batter-backed CMOS static RAMs when used in portable microcomputer applications. The device can be switched off when not in use, a technique that can give the bubble chip an overall power consumption less than that of the RAM. This fact, when coupled with the device's ruggedness and density per square inch, makes the bubble-memory an attractive alternative to CMOS static RAMs.

By packing 8K bytes of ROM onto a single chip, the first step in putting an operating system on a chip has been taken. The S83 from American Microsystems Inc. is just such a device, and was built using 3 micrometer technology and a clever adaptation of CP-M. The Z80-based device also features decoding logic as well as control logic for data buses and external RAM. All of this fits onto a chip less than 40,000 mils square and smaller than current microprocessors having 4-kbytes of ROM. The device can also serve as an auxiliary controller, connected as a slave to a host.

Several milestone achievements were unveiled at a recent International Solid-State Circuits Conference. Most notable is a 32K-by-8-Bit static RAM that packs well over 1 million active devices onto an area slightly over 6 by 8 mm. The device from Toshiba Ltd uses 1.2 micromillimeter technology. Also attracting attention at the conference were 256K-bit dynamic RAMs which have been fine tuned to obtain extremely fast access times at low power levels. Fujitsu has developed the smallest GaAs RAM yet reported - only 47 by 32 micromillimeters. More than 26,000 FETs are contained on the device, the highest density level yet attained.

Fabrication processes that are based on CMOS, bipolar, and GaAs technologies are coming to the aid of the latest computer- aided design tools. This should help create a healthy breed of faster and denser gate arrays. Picosecond delays are also more realistic with bipolar arrays these days. Work has been done on a 2500-gate master slice that has 280-ps gate delays for a fan-out of one.

Capacitor advances and packaging for ICs were the big topics of discussion for the ECC show. One of the advances in capacitors is a solid-electrolytic that relies on an aluminum and powdered- titanium alloy to reduce cost. Research was done by NEC Corp.'s Fundamental Research Labs. Mitsubishi Electric Corp. at the same time has addressed IC packaging. Improvements in IC lithography make possible line fabrications of less than twenty microns on multilayer substrates. These new packages have excellent thermal-handling characteristics for flip-chips and chips mounted upside down on hybrid substrates.

Semiconductor manufacturers agree that IC's will be taking on a new packaging in the future. With the advances in technologies, it is clear that new packaging will come. It will probably be square, but lead placement is still a question. There is talk now of bipolar and CMOS chips with 300 leads and microprocessor chips with 100 leads.

The way is clear for today's silicon VLSI chips; the super- VLSI circuits are coming. By the 1990's we will see 4-Mbit dynamic RAMs and 32-bit pocket microcomputers. Tremendous improvements have been made just in the last ten years: smaller transistors, self-alignment, the structure of MOS devices. Included are drawings that show the growth of the dynamic RAM and self-alignment technology.

Many advances are seen in the near future including full-system chips and new developments with GaAs LSI circuits. In GaAs technology, a 504-gate logic array with 64bits of RAM has been developed. Several companies are working with this new technology and advances are predicted. Several drawings show different aspects of these highly technical digital ICs.