FIELD-EFFECT TRANSISTOR WITH UNIFORM SOURCE/DRAIN REGIONS ON SELF-ALIGNED DIRECT BACKSIDE CONTACT STRUCTURES OF BACKSIDE POWER DISTRIBUTION NETWORK (BSPDN)

Provided is field-effect transistor structure including: a channel structure; a source/drain region and a 2nd source/drain region connected to each other through the channel structure; a 1st contact plug, on a top surface of the 1st source/drain region, connected to a voltage source or 1st circuit element through a back-end-of-line (BEOL) structure; and a 2nd contact plug, on a bottom surface of the 2nd source/drain region, connected to the 1st voltage source, through a backside power rail, or another circuit element, wherein the 1st source/drain region and the 2nd source/drain region have a substantially same height.