Band offsets and work function control in field effect transistors
Schematic definition of EWF. Energies refer to Si band edges, and only thereby to the vacuum level.
(a) Comparison of effective work functions of metals on and against metal index, after Schaeffer et al. (b) Data replotted as EWF on vs work function on . Slope derived from data over the narrow range of 4.1–5.1.
(a) Effective work functions of metals on , from internal photoemission data (Ref. 14), as extracted by Yeo et al. (Ref. 11). (b) Effective work functions of metals on , from internal photoemission data (Ref. 14) and also from CV data cited by Yeo et al. (Ref. 11).
(a) Effect of annealing in and in forming gas, after Cartier (Ref. 18), and (b) effective work function vs EOT for metal electrodes on on , after Lee et al. (Ref. 3), showing the roll-off effect.
(a) Effective work functions of refractory metals on , , and as found by Mahji et al. (Ref. 20). (b) Data replotted as EWF on vs EWF on . This gives a slope .
(a) Schematic of the three types of faces of polar crystals. (b) Schematic of interfaces of nonpolar and polar interfaces with metals, and the image charge response of the metal.
Atomic configurations of lattice matched interfaces of Ni(100) on .
(a) Interface formation energy of interfaces vs O chemical potential. (b) For interfaces. V is more electropositive.
(a) Interface formation energies (polar and nonpolar) vs metal. (b) Calculated valence band offsets of metal: interfaces.
(a) Band bending due to charge O vacancy formation next to electropositive gate metal. Vacancies placed at fixed distance from interface in order to give an analytic model (Ref. 74). (b) Formation energy of the O vacancy as a function of Fermi level in the oxide.
Bulk free energies of metal oxides per O atom vs work functions of the parent metal showing chemical trend.
Formation of O vacancy and unit by reaction and associated band bending. Vacancies placed at fixed distance from interface in order to give an analytic model (Ref. 74).
Article metrics loading...
Full text loading...