described in kyoung rok han et al design considerations of body tied finfets u0302 mosfets implemented on bulk si wafers journal of semiconductor technology and science 4 1 12 2004 can also be fabricated with a junctionless architecture provided appropriate electrical isolation from the substrate is achieved in one embodiment the source the drain and connecting channel comprises a n n n device to provide a junction less device in another embodiment the source the drain and connecting channel comprises a p p p device to provide a junction less device preferably the doping concentration in the source and drain is approximately 1 u00d7 10 19 to 1 u00d7 10 2 u00b0 atom cm 39 it will be appreciated that the doping concentration depends on the cross sectional dimensions of the channel the doping decreases as the dimensions are increased in order to allow for the gate potential to deplete the channel of carriers when the device is turned off the cross section of the channel is a section through the device that is perpendicular to the source to drain direction the term u201c cross section dimensions u201d or u201c cross sectional dimensions u201d includes the u201c width u201d and the u201c height u201d or u201c thickness u201d of the semiconductor channel it applies to devices such as finfets where the height is larger than the width devices such as trigate transistors where the width is sensibly equal to the height and nanoribbon devices where the width is larger than the thickness it also applies to devices with a rounded or circular cross section and planar soi devices which are essentially nanoribbon devices.