Numerical Modeling-Enabled High-Temperature Characterization of Boron Doped Diamond Ohmic Contact and Material Resistivity Using a Simplified TLM Structure

M. Pietrzyk (CEA en Occitanie, France), D. Trémouilles (LAAS-CNRS, France), E. Marcault (CEA en Occitanie, France), K. Isoird (LAAS-CNRS, France)

Power electronics is essential in the global shift towards electrification and the phase-out of fossil fuels. Diamond power-device technology holds significant promise but requires further research, particularly in high-temperature operations. Accurate characterization of both the material and its electrical contacts is crucial for assessing this technology. Traditional methods like the Transmission Line Method (TLM) and circular TLM have specific sample requirements, which are challenging to meet with diamond due to its emerging status and the limitations of small, non-standard samples. This paper presents a novel approach to extract diamond resistivity and specific contact resistivity using simplified TLM test structure's numerical model. The resistivity of boron-doped diamond (5.7 × 1019 cm-3) and the specific resistivity of its Ti/Pt/Au ohmic contact were extracted. For temperatures between 27°C and 427°C, diamond resistivity varies from 1.21 Ω.cm to 0.02 Ω.cm and specific contact resistivity varies from 4.71 × 10-4 Ω.cm2 to 4.00 × 10-5 Ω.cm2. The results demonstrated the effectiveness for emerging technologies. Future work will focus on further investigation of sample’s behavior at high temperatures and the automation of the method through algorithmic parameter research coupled with finite element simulation.