According to Moore's Law, which has been true so far, transistors density on a chip area doubles every two years. This increase in number of transistors requires reduced device dimensions or to say scaling by a factor of ~0.7. As the device dimensions are shrinking, high temperature processes used in CMOS device fabrication, e.g. thermal oxidation of silicon to grow gate oxide, are becoming incompatible with CMOS processing. High temperature processes could change the impurity profile in Si, produce stresses on Si wafer, and also result in high thermal budget. In the past, many attempts have been made to reduce
In this paper we present the channel degradation properties of MOSFET with gate oxide grown using electron cyclotron resonance (ECR) plasma. Si was oxidized using ECR plasma of 10% O2/He at 450°C for 60 min. MOS and MOSFETs devices were fabricated, using ECR grown oxide as a gate oxide, to evaluate the electrical properties. We found that the n-MOSFET with ECR as-grown oxide shows poorer channel degradation properties, by approximately two orders of magnitude, compared to channel with thermally grown (at 950°C) dry oxide. When as-grown oxide was annealed at much higher temperature (~800oC), channel resistance for the hot carriers improved and became comparable to that of the thermally grown oxide. We have shown that because of the lower processing temperatures used during oxidation strain is present in the bulk oxide and also at Si-SiO2 interface. Annealing at higher temperature can relieve strain and this assumption was found be self consistent with the infrared absorption study.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.