How close can one come to perfection? In the case of Melissa Hines, an assistant professor of chemistry at Cornell University, it could be only an atom away. Her goal: a mirror surface above which not even a single atom protrudes. About five years ago, Bell Labs researchers found that by changing the acidity and composition of a chemical solution, they could produce small areas on a silicon chip that were totally flat, even at the atomic level. Surface roughness was equal to only one protruding atom out of every 30,000 surface atoms. Even on the atomic scale, however, such roughness can greatly decrease the performance of a transistor. The problem: such surface perfection is only reproducible on one type of silicon surface, silicon (111). This is a different plane from silicon (100), used for integrated circuits. Hines wants to find chemical solutions that produce perfection on different surfaces. To do this, she needs to know how a basic hydrofluoric acid solution used in her research etches away protruding atoms. To date, the most perfect surface appears through the electron tunneling microscope as a series of steps, with every step only a single atom high. The steps are the result of almost imperceptible errors in cutting a silicon wafer. If perfected, Hines sees the etching technique useful for integrated circuit technology, micromachining of very small parts, and for producing thin films. That feat, says Hines, is about five years away. E-mail email@example.com.
At the Design News webinar on June 27, learn all about aluminum extrusion: designing the right shape so it costs the least, is simplest to manufacture, and best fits the application's structural requirements.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.