Dielectric based charge carrier tuning for CNT CMOS inverters

Abstract

The realization of Carbon nanotube (CNT) based CMOS compatible complementary logic circuits is one of the bottlenecks that needs to be overcome in order to consider CNTs as an alternative to silicon in future CMOS technology. In this work, we demonstrate complementary logic inverters using solution-processed CNTs. The type of charge carriers in the CNT field effect transistors (FET) have been tuned by changing the dielectric environment to realize both p-type and n-type CNTFETs. We have fabricated p-type CNTFETs using electron beam evaporated HfO 2 as the top-gate dielectric and n-type CNTFETs using plasma enhanced chemical vapor deposition grown Silicon nitride as the top-gate dielectric. Using this fabrication approach, we realize high performance p-and n-CNTFETs employing regular metals such as Palladium for the source/drain contacts instead of rare earth metal contacts such as scandium. We demonstrate complementary logic inverters with a DC gain as high as 6.7 and operating voltages within 1 V.

PECVD grown silicon nitride ultra-thin films for CNTFETs

“…Thickness of SiO 2 is ∼290 nm and the highly doped P++ Si substrate is used as back-gate. The fabrication of CNTFET is similar to our previous work on CNTFET CMOS inverter [33]. The channel length of the devices is fixed to 1 μm in our study and the channel width is defined by the width of the CNT strips formed during self-assembly process.…”

High-Performance Organic Field-Effect Transistors Using Rare Earth Metal Oxides as Dielectrics

“…1 Exploiting REOs as gate dielectrics is considered as one of the most promising ways for further evolution of Si-based electronic technologies nowadays. REOs were also used in field-effect transistors (FETs) with oxide semiconductors, 2−5 gallium nitride and other A(III)−B(V)type semiconductors, 6 transistors with carbon nanotubes (CNTs), 7 etc. 8 Organic electronics can also largely benefit from using REOs as dielectrics in organic field-effect transistors, as it has been shown recently in a few pioneering reports.…”

“…Exploiting REOs as gate dielectrics is considered as one of the most promising ways for further evolution of Si-based electronic technologies nowadays. REOs were also used in field-effect transistors (FETs) with oxide semiconductors, − gallium nitride and other A­(III)–B­(V)-type semiconductors, transistors with carbon nanotubes (CNTs), etc …”