Protonic Memory

One of the minor horrors of the computer age is to be working on a document not yet saved to the hard drive and lose everything because of a power outage or a system crash that forces the operator to shut down the computer.

Attempts to create circuits that store the information when the power is interrupted have used high voltages, which quickly wear down computer electronic components, and have been expensive. Now scientists at Sandia and at France Telecom have applied for a patent on a prototype memory retention device that is inexpensive, low-powered, and simple to fabricate.

To transmit data, the device uses embedded protons, which remain where they are when the power turns off, thus preserving the information. In devices such as DRAM's (dynamic random access memory), typically based on electron flow, the information is lost when the power is turned off.

To create the memory retentive chip, only a few steps must be added to the hundreds currently used to fabricate microchips. The key additional step is to bathe the hot microchip in hydrogen gas. The gas, permeating the chip, breaks up into single ions - protons - at defects in the silicon dioxide. (The defects are created by the heat of the manufacturing process.) The protons can roam only within the chip's central layer of silicon dioxide, where they are trapped by two layers of silicon that sandwich the silicon dioxide.

The Sandia researchers found that:

A positive low voltage applied to one side of the silicon repels the protons to the far side of the silicon dioxide.

A negative low voltage applied to the silicon attracts the protons to the near side of the silicon dioxide.

If the power is turned off, the protons stay where they are, retaining information in the chip circuit.

First observation of the effect that protons remain in silicon when it is baked at high temperatures in hydrogen gas came as part of a systematic study at Sandia and France Telecom of the effects of hydrogen on silicon.