Composition Comprising Rare-earth Dielectric

Abstract

Compositions comprising a single-phase rare-earth dielectric disposed on a substrate. Embodiments of the present invention provide the basis for high-K gate dielectrics in conventional integrated circuits and high-K buried dielectrics as part of a semiconductor-on-insulator wafer structure.

1 . A composition comprising:
 a first layer comprising a first rare-earth;   a second layer comprising a second and third rare-earth;   a third layer comprising a fourth rare-earth; and   a fourth layer comprising a Group IV semiconductor wherein the second layer separates the third layer from the first layer and the third layer separates the fourth layer from the second layer such that the third rare earth is different from the first rare earth and the first, second and fourth rare earth may be the same.   
     
     
         2 . The composition of  claim 1  further comprising a fifth layer comprising a fourth rare earth and a sixth layer comprising a Group IV semiconductor wherein the fifth layer separates the sixth layer from the fourth layer. 
     
     
         3 . The structure of  claim 2  wherein said fifth layer comprises at least two layers with at least two different rare earths in one of the at least two layers. 
     
     
         4 . The structure of  claim 1  wherein at least one of said first, second, third and fourth rare earth is chosen from a group consisting of erbium, ytterbium, dysprosium, holmium, thulium, and lutetium. 
     
     
         5 . The structure of  claim 1  wherein at least one of said first, second, third and fourth rare earths is a rare-earth of atomic number greater than or equal to 66. 
     
     
         6 . The composition of  claim 1  wherein said fourth layer comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide. 
     
     
         7 . The composition of  claim 2  wherein said sixth layer comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide. 
     
     
         8 . The composition of  claim 2  wherein at least one of said fourth layer and sixth layer are a quantum dot structure. 
     
     
         9 . The composition of  claim 1  further comprising a seed layer such that the first layer is between the seed layer and the second layer. 
     
     
         10 . The composition of  claim 2  further comprising a seed layer such that the seed layer is between the fourth layer and the fifth layer. 
     
     
         11 . The composition of  claim 1  wherein said third layer further comprises a termination layer and a nucleation layer.