Brian Standley

Over the last number of years, graphene has been the focus of intense research into its electronic, mechanical, and chemical properties, especially as they relate to logic circuit applications. While much of this effort has focused on transistor-like devices, non-volatile memory elements are needed as well. I (along with collaborators) discovered a way to make and operate an example of the latter:

Steps 3 and 4 can be repeated at least ~10⁴ times without degrading the device. The conducting channels are thought to be linear chains of carbon atoms "unzipped" from the edges of the graphene sheets, as described in Rinzler et al and Lang et al. For more information, see the link to the paper below.

Graphite oxide (GO) has generated interest in a wide array of fields – from supercapacitors to electronics to nano-paper. I (with collaborators) worked to make a top-gated graphene field-effect transistor using GO as the gate dielectric, rather than boron nitride or various bulk insulators such as SiO₂ or HfO₂ as had been done before. Such devices show little gate leakage current (even at room temperature) and a breakdown field comparable to SiO₂. Alas, the material's relative dielectric constant (κ) appears to be only slightly higher than SiO₂ ~ 4.3.

GO's utility for graphene electronics is of particular interest because both graphite oxide and graphene are layered materials. In addition, GO can be made directly from graphene in various ways. One might imagine turning an n-layer stack of graphene sheets into self-aligned a n-m layer graphene + m layer graphite oxide device, or using layer transfer to make more complicated stacks.² For for information, see the link to the paper below.

Scriptable continuous and triggered data acquisition for Linux and Windows

As nanoelectronics experiments and associated instrumentation continue to grow in complexity, the need for powerful data acquisition software has only increased. This role has traditionally been filled by all-in-one devices such as semiconductor parameter analyzers (SPAs) or by stand-alone desktop computers running National Instruments LabVIEW. Mezurit 2 represents a hybrid approach, combining the ease-of-use of SPAs with some of the flexibility of LabVIEW. It can control multiple inputs and outputs in real time while simultaneously plotting data and executing Python-based scripts.

For more information, or to download the source code, visit the project page.

awcgen - A Perl script to generate AWC-compatible waveforms for the SRS DS345 Function Generator.

npgsfixer - A Perl script to modify DesignCAD files imported from DXF to work with NPGS. Also fractures patterns.

Sometime you need more than 10 V to characterize semiconductors (especially graphene-based devices). Thus, the BGVA is a two-stage 10X voltage amplifier capable of smoothly sweeping from -80 to 80 V. It is powered by isolated DC/DC converters which are easily stacked to achieve the necessary supply voltages. As a bonus, this design eliminates a potential ground loop on the power supply side.

For more information, see its "datasheet." Right now only the prototype exists, but addition copies could be made fairly inexpensively if there is interest.