Suspended Nanoscale Field Emitter Devices for High-Temperature Operation

MEMS, Field-Emitter, Thermal, and Fluidic Devices

Nanoscale temperature mapping in operating microelectronic devices

Modernmicroelectronic devices have nanoscale features that dissipate power nonuniformly, but fundamental physical limits frustrate efforts to detect the resulting temperature gradients. Contact thermometers disturb the temperature of a small system,while radiation thermometers struggle to beat the diffraction limit. Exploiting the same physics as Fahrenheit’s glass-bulb thermometer, we mapped t...

Improving the Performance of GaN Power Devices for High Breakdown Voltage and High Temperature Operation

tion as an alternative to Si as a semiconductor material for ultra-low-loss power devices. Early development of GaN was carried out in the area of light-emitting devices—green LEDs, lasers, etc.—but its superior performance as noted above and the needs of society led to R&D work for electronic devices being conducted world-wide. Specifically, the AlGaN/GaN HFET structure permits the formation o...

High-Temperature Stable Operation of Nanoribbon Field-Effect Transistors

We experimentally demonstrated that nanoribbon field-effect transistors can be used for stable high-temperature applications. The on-current level of the nanoribbon FETs decreases at elevated temperatures due to the degradation of the electron mobility. We propose two methods of compensating for the variation of the current level with the temperature in the range of 25-150°C, involving the appl...

High-quality multiterminal suspended graphene devices.

We introduce a new scheme to realize suspended, multiterminal graphene structures that can be current annealed successfully to obtain uniform, very high quality devices. A key aspect is that the bulky metallic contacts are not connected directly to the part of graphene probed by transport measurements, but only through etched constriction, which prevents the contacts from acting invasively. The...