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Direct-write Process for 3D Transistors Offered

Lithography-free process looks more attractive for rapid prototyping of discrete transistors

2 min read
Direct-write Process for 3D Transistors Offered

It seems that ever since the term nanotechnology started getting bandied about in the field of electronics people have been forewarning of the eventual death of the complementary metal oxide semiconductor (CMOS). At a recent IEEE Nanotechnology Symposium meeting, Dr. Hans Stork’s, VP and CTO Applied Materials is reported as suggesting that CMOS will remain the backbone of the electronics industry and he is not really expecting a “post-CMOS” world.

He seems to be right. So far, attempts to work outside of the CMOS paradigm are ultimately met with assimilation: “Resistance is futile” to quote a Star-Trek Borg. At least one example of this might be Zettacore, which started out as trying to replace silicon with molecular memory technology, and instead ended up making its business focus improving semiconductor manufacturing.

But forever is a long time and while CMOS has things tied up until at least 32-nm dimensions, and possibly until 22 nm and 16 nm as well, it may need some new functional materials and hybrid platforms to continue its ever-downward push.

The latest to come down the pike comes from the researchers at the Institute of Bioengineering and Nanotechnology (IBN), which I had the privilege of getting a tour of a few years back.

The IBN researchers, who originally reported their work in the Institute of Physics journal Nanotechnology, have developed a direct-write fabrication process that negates the need for lithography for producing discrete field-effect transistors. The process employs an electron beam or ion beam to scan over a sample in the presence of a precursor gas that results in material to be deposited directly onto the sample with nanomater resolutions.

According to an article in Nanowerk, one of the researchers, Somenath Roy, sees that this method is better for rapid prototyping than lithography-based techniques.

“Our single-step fabrication technique obviates the time-consuming and labor-intensive lithography process, and enhances the fabrication accuracy and yield," says Roy. "With a higher level of precision and throughput, it can offer a powerful method for rapid prototyping of futuristic nanoelectronic circuits."

Well, yeah, I guess it might be better than lithography techniques for prototyping but what about full-scale production? Roy suggests in the Nanowerk article that with “further optimization” the direct-write process could eventually lead to scalable nanoscale integrate circuit fabrication. Just remember, forever is a long time.

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The Transistor at 75

The past, present, and future of the modern world’s most important invention

2 min read
A photo of a birthday cake with 75 written on it.
Lisa Sheehan

Seventy-five years is a long time. It’s so long that most of us don’t remember a time before the transistor, and long enough for many engineers to have devoted entire careers to its use and development. In honor of this most important of technological achievements, this issue’s package of articles explores the transistor’s historical journey and potential future.

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