Abstract: A transistor includes a first semiconductor layer, a second semiconductor layer, a semiconductor nanosheet, a gate electrode and source and drain electrodes. The semiconductor nanosheet is physically connected to the first semiconductor layer and the second semiconductor layer. The gate electrode wraps around the semiconductor nanosheet. The source and drain electrodes are disposed at opposite sides of the gate electrode. The first semiconductor layer surrounds the source electrode, the second semiconductor layer surrounds the drain electrode, and the semiconductor nanosheet is disposed between the source and drain electrodes.

Abstract: Methods for preparation of a carbon membrane include providing a solution comprising a diacetyl biphenyl monomer and an alkylsulfonic acid. The solution is treated under such conditions that an aldol condensation reaction occurs so as to produce a porous polymer network. The porous polymer network is treated under such conditions that a Scholl reaction occurs.