Single-Molecule Chemical-Field-Effect Transistor with Nanometer-Sized Gates

May 7, 2004

F. Jackel and group of scientists from Max-Planck-Institute and Humboldt University Berlin, Germany present a prototypical single-molecule chemical-field-effect transistor, in which the current through a hybrid-molecular diode is modified by nanometer-sized charge transfer complexes covalently linked to a molecule in an STM junction. Their article is published in the last Physical Review Letters issue ( vol. 92, no. 18 )

The semiconductor industry has seen a remarkable miniaturization trend, driven by many scientific and technological innovations. But if this trend is to continue, and provide ever faster and cheaper computers, the size of microelectronic circuit components will soon need to reach the scale of atoms or molecules—a goal that will require conceptually new device structures. The idea that a few molecules, or even a single molecule, could be embedded between electrodes and perform the basic functions of digital electronics—rectification, amplification and storage—was first put forward in the mid-1970s. The concept is now realized for individual components, but the economic fabrication of complete circuits at the molecular level remains challenging because of the difficulty of connecting molecules to one another. A possible solution to this problem is 'mono-molecular' electronics, in which a single molecule will integrate the elementary functions and interconnections required for computation.

Transistors, traditionally made from silicon, regulate the transmission of electrons across barriers. The barrier height, and hence the electron flow, can be controlled by applying a small voltage to an electrode that acts as a gate.

A single molecule with a donor–spacer–acceptor structure behaves as a diode when placed between two electrodes: electrons can easily flow from the cathode to the acceptor, and electrons from the donor are then transferred to the anode. The working principle of this device is analogous to that underlying the "valve" effect introduced by Schockley 60 years ago, but involves manipulating the electronic wavefunction of the metallic electrodes extending through the donor–spacer–acceptor molecule, rather than the carrier density in a semiconductor material.

Scanning tunnelling microscope enables controlled two-terminal measurements, and its development has thus allowed new experimental approaches for demonstrating and probing electron transport through individual molecules.

Nanolithography has made important contributions towards using mesoscopic electrodes and nanojunctions for hybrid molecular electronics.

Field effect transistors have been fabricated with carbon nanotubes and single molecules. The electrodes, however, were macro- or mesoscopic and not readily scalable to nanoscale dimensions.

Authors present a prototypical three-terminal device at the solid-liquid inter-face, in which the current through a hybrid-molecular diode is modified by nanometer-sized charge transfer complexes (‘‘nanogates’’) covalently linked to the mole-cule in the STM junction.

They regarded this proof of principle as a major step towards monomolecular electronic devices and highly sensitive electronic molecular probes.

Explore further: Modeling electron excitation in organic photovoltaic material could change the future of solar energy

Related Stories

Molecular nanoribbons as electronic highways

October 1, 2015

Physicists at Umeå University have, together with researchers at UC Berkeley, USA, developed a method to synthesise a unique and novel type of material which resembles a graphene nanoribbon but in molecular form. This material ...

Meet the high-performance single-molecule diode

July 29, 2015

A team of researchers from Berkeley Lab and Columbia University has passed a major milestone in molecular electronics with the creation of the world's highest-performance single-molecule diode. Working at Berkeley Lab's Molecular ...

Recommended for you

Horn of Africa drying ever faster as climate warms

October 9, 2015

The Horn of Africa has become increasingly arid in sync with the global and regional warming of the last century and at a rate unprecedented in the last 2,000 years, according to new research led by a University of Arizona ...

Scientists paint quantum electronics with beams of light

October 9, 2015

A team of scientists from the University of Chicago and the Pennsylvania State University have accidentally discovered a new way of using light to draw and erase quantum-mechanical circuits in a unique class of materials ...

What are white holes?

October 9, 2015

Black holes are created when stars die catastrophically in a supernova. So what in the universe is a white hole?

How to prepare for Mars? NASA consults Navy sub force

October 5, 2015

As NASA contemplates a manned voyage to Mars and the effects missions deeper into space could have on astronauts, it's tapping research from another outfit with experience sending people to the deep: the U.S. Navy submarine ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.