Improved Body Effect and Analog Characteristics of n-Channel MOSFET With Lateral Asymmetric Substrate Doping

An n-channel MOSFET with lateral asymmetric substrate doping (LASD) is presented in this paper. The proposed LASD device has a p-well on the source side and a p-substrate on the drain side. The LASD MOSFET was designed by the simple p-well layout approach and fabricated using the 0.18
\(\mu \)
m standard low-voltage CMOS process without any process modification. The experimental measurements showed the improved analog performances of the LASD MOSFET: higher transconductance (g
\(_{\mathbf {m}}\)
), lower drain conductance (g
\(_{{\mathrm {ds}}}\)
), lower drain induced barrier lowering, higher transconductance generation factor (g
\(_{{\mathrm {m}}}/{\mathrm I}_{{\mathrm {D}}}\)
), and higher Early voltage (V
\(_{{\mathrm {EA}}}\)
). In addition, the LASD device showed strong body-effect immunity: smaller V
\(_{{\mathrm {T}}}\)
shift according to body bias and lower body bias sensitivity factor (g
\(_{{\mathrm {mb}}}/{\mathrm g}_{{\mathrm {m}}}\)
).