Effect of body structure on analog performance of SOI NMOSFET´s

Summary form only given. Recently, SOI devices have been applied to high performance mixed analog/digital or analog circuits. SOI devices with a modified structure were investigated for analog applications (Chan et al, 1995). We have studied the effect of body structure on analog performance of SOI NMOSFETs. The body structures are lateral body-floating (without body contact), lateral body-tied, and vertical body-tied, respectively. Three device structures are fabricated on the same wafer by wafer bonding and etch-back technology. Key analog parameters such as g/sub m/r/sub o/ and 1/f noise are measured and compared. The lateral body-tied device shows the lowest 1/f noise spectral density. The vertical body-tied SOI device has the best g/sub m/r/sub o/ characteristics at V/sub DS/ of 3 V and I/sub D/ of 10 /spl mu/A. We also showed the g/sub m/r/sub o/ characteristics of vertical body-tied SOI devices with different boron implantation dose for doping of the buried polysilicon body electrode.