Multiring Circular Transmission Line Model for Ultralow Contact Resistivity Extraction

Accurate determination of contact resistivities (rho(c)) below 1 x 10(-8) Omega center dot cm(2) is challenging. Among the frequently applied transmission line models (TLMs), circular TLM (CTLM) has a simple process flow, while refined TLM (RTLM) has a high rho(c) accuracy at the expense of a more complex fabrication. In this letter, we will present a novel model-multiring CTLM (MR-CTLM), which combines the advantages of a simple process and a high rho(c) extraction resolution. We fabricated ultralow-rho(c) Ti/n-Si contacts and demonstrated the capability of MR-CTLM to extract the rho(c) as low as 6.2 x 10(-9) Omega center dot cm(2) with high precision.