F. Sinisi

K-band diamond MESFETs for RFIC technology

Diamond is one of the suitable semi-conductor for vacuum electronics replacement in high power and high frequency applications. Sub-micron gate-length (200 nm) Metal Semiconductor Field Effect Transistor (MESFETs) have been fabricated on h-terminated polycrystalline diamond and characterized in order to investigate the possibility of RFICs integration. High power (Pout=1.5 W/mm) and high frequency (and fMAX=35 GHz) performances have been obtained.

Microwave performance of surface channel diamond MESFETs

Sub-micron gate length Metal Semiconductor Field Effect Transistors (MESFETs) have been realized on polycrystalline diamond samples supplied by Element Six Ltd. and by Russian Academy of Science. RF performances are shown for devices realized on polycrystalline diamond samples of different quality, stating the successfully improvement and reliability of realization technology.

MESFETs on H-terminated polycrystalline diamond

Metal-Semiconductor Field Effect Transistors (MESFETs) were fabricated on polycrystalline diamond. Devices were realized to be employed in Microwave Integrated Circuits for satellite communications and high frequency power amplification, areas were diamond promise the replacement of vacuum electronics. Fabricated MESFETs typically showed high drain-source current (140 ma/mm) and large transconductance values (50 ms/mm), with a cut off frequency ft=10 GHz and a maximum oscillation frequency, fmax, up to 35 GHz. These values suggest device microwave operation and are obtained through the fabrication of devices with geometry and active region dimensions (200–500 nm gate length) compatible with available microelectronic technologies.

Microwave operation of sub-micrometer gate surface channel MESFETs in polycystalline diamond

Metal-Semiconductor field effect transistor (MESFETs) were fabricated on hydrogen-terminated polycrystalline diamond. Fabricated MESFETs typically showed high drain-source current (140 mA/mm) and large transconductance values (60 mS/mm), with a cut off frequency f T =10 GHz and a maximum oscillation frequency, f MAX , up to 35 GHz. These values suggest device microwave operation in the K- band and are obtained through the fabrication of devices with geometry and active region dimensions compatible with available microelectronic technologies. Devices were realized in order to be employed in Microwave Integrated Circuits for satellite communications and high frequency power amplification, areas where diamond promises the replacement of vacuum electronics: with this perspective, our group realized a first important step formulating an equivalent circuit (EQC) model.