Indium gallium arsenide transistors as silicon alternatives

¶ … Moore's Law without Silicon

Written by Kate Greene and published by MIT in Technology Review

The article builds on a development by MIT scientists unveiled at a previous International Electron Device meeting. The scientists had created a transistor made without silicon, using a compound called indium gallium arsenide instead. Their transistor had the capacity to operate more than twice as fast as an equally-sized silicon transistor. The silicon-free transistor technology offers benefits for microprocessors, may help maintain Moore's Law, and, with further research, could revolutionize electrical engineering.

Silicon, the dominant semiconductor for transistors, is not the best material for fast processing. The article explains that, in silicon, electrons move slower than electrons in compound semiconductors. Additionally, as microprocessors get smaller, the silicon dioxide insulation becomes thinner, resulting in excess heat and power dissipation. Finally, the article points out the theory that silicon may not be able to be pushed further to make smaller transistors. As such, researchers have been looking for alternatives to silicon transistors for the future of microprocessors. Ideally, replacement materials would offer faster speeds at smaller sizes without the drawbacks of silicon.

The transistor developed by the MIT scientists is not entirely unique research. The article points out that numerous other research institutions have been working on similar projects. However, MIT's transistor is special because it offers a high level of performance in a small transistor. They also developed a technology to make the insulating material, indium aluminum arsenide, thinner. Consequently, the silicon-free technology discussed in this article offers a viable alternative to silicon.

Moore's Law postulates that, every two years, the number of transistors on a chip will double. Behind Moore's Law is the theory that transistors get better as they get smaller. The article points out that some scientists are adamant that silicon continues to be the future of microprocessors. However, others are opting to look for materials that have better properties than silicon. The article highlights the benefits of compound materials, such as indium gallium arsenide, for transistors.

This technological development impacts Moore's Law by providing a means to continue it holding true. In order for the number of transistors on a chip to continue doubling every two years, they should continue to get better as they get smaller or there would be no reason to continue increasing the number of transistors. If silicon does not continue to offer the benefits of smaller transistors, Moore's Law will become false if another material does not replace silicon in transistors.