Characterization of ultra-thin SOI MOSFETs by coupling effect between front and back interfaces

By investigating the coupling effect between the front and back channels of ultra-thin SOI-MOSFETs, the mobility enhancement by volume inversion, the channel separation between the front and back channels, and the impact of the SOI thickness are discussed. As a result, it is shown that a careful check is necessary for confirming which channel (front or back) is inverted in a short device because the channel separation is difficult in transconductance curves. Furthermore, it is shown that the SOI thickness depends on the device size and location, leading to a complex behavior.