875-MW/cm² Low-Resistance NO₂ p-Type Doped Chemical Mechanical Planarized Diamond MOSFETs

Abstract

In this study, an Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> passivated, NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> p-type doped diamond metal–oxide–semiconductor field-effect transistor (MOSFET) was fabricated on a chemical mechanical planarized high-quality heteroepitaxial diamond (Kenzan diamond <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> ) substrate. This MOSFET exhibited a low specific ON-resistance of 7.54 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}\Omega \cdot $ </tex-math></inline-formula> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and a high OFF-state breakdown voltage of −2568 V. The chemical mechanical planarization (CMP) was performed for 200 h on the diamond surface which effectively removed the subsurface damages resulting in a low resistive diamond surface. Thus, the MOSFET showed a high drain current density of −0.68 A/mm and a maximum available power density (Baliga’s figure-of-merit) of 874.6 MW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> —the highest reported value for diamond devices.