Investigation of Ohmic Contact Resistance, Surface Resistance, and Channel Resistance for Hydrogen-Terminated Diamond MOSFETs
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2022-01-19 |
| Journal | IEEE Transactions on Electron Devices |
| Authors | Jiangwei Liu, Hirotaka Ohsato, Bo Da, Yasuo Koide |
| Institutions | National Institute for Materials Science |
| Citations | 5 |
Abstract
Section titled “Abstract”The ohmic contact resistance ( <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{C}$ </tex-math></inline-formula> ), surface resistance ( <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{S}$ </tex-math></inline-formula> ), and channel resistance ( <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{\text {CH}}$ </tex-math></inline-formula> ) of hydrogen-terminated diamond (H-diamond) MOSFETs were investigated in this study. Planar-type and T-type H-diamond MOSFETs were employed to analyze them. Because no interspaces exist between the source-drain and gate electrodes for the T-type H-diamond MOSFETs, then <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{S}$ </tex-math></inline-formula> is zero. Both planar-type and T-type MOSFETs show low leakage current densities and good operations. By considering the relationships between the total resistance ( <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> ) and 1/ <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>$\vert $ </tex-math></inline-formula> gate voltage-threshold voltage <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>$\vert $ </tex-math></inline-formula> , <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{C}$ </tex-math></inline-formula> and <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{\text {CH}}$ </tex-math></inline-formula> for the T-type H-diamond MOSFET at a gate voltage of −10.0 V are determined to be 13.8 and 21.8 <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>$\Omega \cdot $ </tex-math></inline-formula> mm, respectively. As <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{C}$ </tex-math></inline-formula> for both MOSFETs is the same, <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{S}$ </tex-math></inline-formula> and <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{\text {CH}}$ </tex-math></inline-formula> for the planar-type H-diamond MOSFET are deduced to be 90.0 and 15.8 <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>$\Omega \cdot $ </tex-math></inline-formula> mm, respectively. <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{S}$ </tex-math></inline-formula> accounts for 75.3% of <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> for the planar-type H-diamond MOSFET, which is the main reason for its lower drain current and extrinsic transconductance than those of the T-type MOSFET. Although <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{S}$ </tex-math></inline-formula> is suppressed for the T-type H-diamond MOSFET, <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{C}$ </tex-math></inline-formula> occupies 38.8% of <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{ \mathrm{\scriptscriptstyle ON}}$ </tex-math></inline-formula> . To further improve the performance of the H-diamond MOSFETs, it is important to eliminate <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}{S}$ </tex-math></inline-formula> and decrease <inline-formula xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”> <tex-math notation=“LaTeX”>${R}_{C}$ </tex-math></inline-formula> to further improve the electrical properties of the H-diamond MOSFETs.