Whatever Happened to Bubble Memory?

by John C. Dvorak

It was the rage: bubble memory–an invention that promised to replace the hard disk. Invented by Bell Labs in the 1970s, it was commercialized by Intel, and heavily marketed in the early 1980s as the ultimate answer for microcomputer memory storage.

Bubble memory would replace the hard disk, said its proponents. Not only would it retain its memory after the computer had been turned off, unlike Dynamic Random Access Memory (DRAM) chips, but it wouldn’t have any moving parts.

The full name was Magnetic Bubble Memory. It was a method of recording data in bubble-like magnetic regions on the surface of a chip. Perhaps its most noteworthy advantage was a ruggedness that attracted the military, which continued to use the technology after its failure in the market. Bubble memory can withstand high temperatures, dust, humidity, and high radiation without falling; it’s also removable.

So what happened? First of all, it turned out to be harder to make bubble memory than expected. The fabrication process never proved to be smooth or cheap enough to compete with other technologies.

Furthermore, it required a complex controller, not unlike a hard disk controller, to make the system work. Worse, it was power hungry. While it was a static technology when inactive, it required a lot of juice to move those bubbles around. Users also discovered that glitches in the data were a problem. And finally, it was slow.

All this added up to expense and inconvenience. The memory chips themselves never came close to the price points of DRAM chips, and hard disks continued to drop in price and improve (a practice still happening). Combined, the two managed to pop bubble memory’s chances at wide acceptance.

While the interest in bubble memory perked up during the 1987-88 DRAM shortage, the technology gravitated towards becoming a niche product for use in rugged environments such as factory automation, satellites, and military hardware. It played a role in the Persian Gulf War where its low capacity, slow speed, and high price were offset by the need for reliability, data integrity, and, for the Pentagon, data security.

Improvements in the technology are still possible. Magnesys, Hitachi, and a number of other companies have funded academic research into bubble memory, including something called Vertical Block Line technology, as well as other methods to increase its storage capacity and, hopefully, lower its price.

While basic research continues, MemTech Technology (Santa Clara, Calif.) is the only company still selling bubble-memory products in the United States. It bought Intel’s magnetics division about five years ago. According to Fred Jorgensen, MemTech’s marketing and sales manager, bubble memory’s traditional strengths still make it the best choice for harsh environments, even though it is twice as expensive per bit as competing non-volatile memory technologies such as Flash Memory and Static Random Access Memory (SRAM) chips.

As usual, when technology enters the marketplace, it needs more than just a heavy marketing campaign to succeed. Consumers have always demanded that technology be affordable as well as functional. Bubble memory was flawed on both counts.

More ominously, the initial makers of bubble memory set out to displace an active and growing technology–Winchester disks. This tactic always arouses skepticism in the community. Intel, in this case, was hoping to horn in on one of the hottest arenas of computerdom: hard disks.

With bubble memory, Intel foolishly assumed that developers would hop on the bandwagon of “new technology” just for the sake of newness. As you’ll see, this type of dreamy idealism is a common thread in the products and topics we’ll examine in “What Ever Happened to…?”