ROBUST GRAPHENE-CONTACTS FOR SiC
Silicon carbide (SiC) devices are used in high-voltage and high-temperature applications. The market share of SiC-devices is still low compared to silicon devices as SiC-transistors only became available recently. However, the new requirements of applications in the field of electromobility and solar energy ask for specifications that SiC-devices meet more easily than conventional Si devices.
Also, epitaxial graphene transistors are suited for high frequency (100 GHz) operation. These materials are among the most robust materials available.
One of the reasons why SiC didn’t replace Si-devices on a larger scale was the non-availability of SiC-transistors, especially “normally-off”-transistors. Our technology now provides such transistors.
The inventions describe simple transistor designs (MOSFET and MESFET) which allow the production of “normally-on” and “normally-off” SiC/epitaxial graphene transistors. The fabrication effort is particularly low and requires in its simplest realization only one lithography step (for MESFET). In addition, the innovation allows for simple graphene-based capacitor and resistor designs. Thus, the integration of the transistors into graphene-based circuits is straightforward.Due to high on/off-ratios analog as well as logic circuits are targeted. The innovation provides availability of a simple SiC/epitaxial graphene transistor with the possibility to create integrated circuits.
- Side-by-side fabrication together with either high-frequency graphene-only transistors or high-power SiC transistors
- Application as integrated control circuit for high power switches
- build a compact constant current source for LEDs
- include the control circuits and the LED on the same SiC-subtrate
Feasibility has been shown.
(1) Nature Communications 3, 957 (2012), doi: 10.1038/ncomms1955
(2) Appl. Phys. Lett. 100, p. 122102 (2012), doi: 10.1063/1.3695157