Interlayer design for epitaxial growth of semiconductor layers

Abstract

An interlayer structure that, in one implementation, includes a combination of an amorphous or nano-crystalline seed-layer, and one or more metallic layers, deposited on the seed layer, with the fcc, hcp or bcc crystal structure is used to epitaxially orient a semiconductor layer on top of non-single-crystal substrates. In some implementations, this interlayer structure is used to establish epitaxial growth of multiple semiconductor layers, combinations of semiconductor and oxide layers, combinations of semiconductor and metal layers and combination of semiconductor, oxide and metal layers. This interlayer structure can also be used for epitaxial growth of p-type and n-type semiconductors in photovoltaic cells.

What is claimed is: 
     
         1 . A layer structure comprising an underlayer comprising one or more deposited metallic sub-layers having a close-packed crystal structure; and
 an epitaxially-grown semiconductor layer deposited on the underlayer.   
     
     
         2 . The layer structure of  claim 1  wherein the underlayer comprises at least one metallic material having a hexagonal close-packed (hcp), face-centered cubic (fcc) or body center cubic (bcc) lattice structure. 
     
     
         3 . The layer structure of  claim 1  wherein the underlayer comprises at least one metallic material having hcp or fcc or bcc lattice structure with a <0001> or <111> or <110> growth directions. 
     
     
         4 . The layer structure of  claim 1  wherein the underlayer comprises at least two metallic materials, wherein a first metallic material of the at least two metallic materials has an hcp lattice structure with <0001> growth directions and a second metallic material of the at least two metallic materials has an fcc lattice structure with <111> growth directions. 
     
     
         5 . The layer structure of  claim 1  wherein the underlayer comprises at least two metallic materials, wherein a first metallic material of the at least two metallic materials has an fcc lattice structure with <111> growth directions and a second metallic material of the at least two metallic materials has a bcc lattice structure with <110> growth directions. 
     
     
         6 . The layer structure of  claim 1  wherein the underlayer comprises at least two metallic materials, wherein a first metallic material of the at least two metallic materials has an hcp lattice structure with <0001> growth directions and a second metallic material of the at least two metallic materials has a bcc lattice structure with <110> growth directions. 
     
     
         7 . The layer structure of  claim 1  wherein the underlayer comprises at least three metallic materials, wherein a first metallic material of the at least three metallic materials has a fcc lattice structure with <111> growth directions, a second metallic material of the at least three metallic materials has a hcp lattice structure with <0001> growth directions, and a third metallic material of the at least three metallic materials has a bcc lattice structure with <110> growth directions. 
     
     
         8 . A layer structure comprising
 an amorphous or nanocrystalline seed layer;   an underlayer comprising one or more metallic sub-layers having a close-packed crystal structure deposited on the seed layer; and   an epitaxially-grown semiconductor layer deposited on the underlayer.   
     
     
         9 . The layer structure of  claim 8  wherein the seed layer comprises Si 3 N 4 . 
     
     
         10 . The layer structure of  claim 8  wherein the seed layer comprises at least one metallic nanocrystalline or amorphous layer. 
     
     
         11 . The layer structure of  claim 10  wherein at least one seed layer comprises at least one element from the group consisting of V, Cr, Mn, Fe, Co, and Ni, and at least one element from the group consisting of B, C, Al, Si, P, Sc, Ti, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Te, Hf, Ta, W, Re, Ir, Pt, and Au. 
     
     
         12 . The layer structure of  claim 10  wherein at least one seed layer comprises 10 to 96 at. % of least one element from the group consisting of V, Cr, Mn, Fe, Co, Ni, and 4 to 50at. % of least one element from the group consisting of B, C, P, Si, Ti, Ge, Zr, Mo, Hf, Ta, and W. 
     
     
         13 . The layer structure of  claim 10  wherein at least one seed layer comprises 10 to 90 at. % of least one element from the group consisting of V, Cr, Mn, Fe, Co, Ni,; 4 to 50 at. % of least one element from the group consisting of B, C, P, Si, Ge, Zr, Mo, Hf, Ta, W; and at least one element from the group consisting of Al, Sc, Ti, Cu, Zn, Ga, Sr, Y, Ru, Rh, Pd, Ag, In, Te, Sn, Re, Ir, Pt, and Au. 
     
     
         14 . The layer structure of  claim 10  wherein at least one seed layer comprises at least one element selected from the group consisting of B, P, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In, Te, Hf, Ta, W, Re, Ir, Pt, and Au. 
     
     
         15 . The layer structure of  claim 8  wherein the underlayer comprises at least one metallic material having a hcp or fcc or bcc lattice structure. 
     
     
         16 . The layer structure of  claim 15  wherein the metallic material of the underlayer has the hcp lattice structure and wherein the underlayer comprises at least one element from the group consisting of Sc, Ti, Co, Zn, Y, Zr, Ru, Hf, and Re. 
     
     
         17 . The layer structure of  claim 15  wherein the metallic material of the underlayer has the hcp lattice structure and wherein the underlayer comprises at least one element from the group consisting of Sc, Ti, Co, Zn, Y, Zr, Ru, Hf, and Re, and at least one element from the group consisting of B, C, N, O, Na, Si, S, P, K, Al, V, Cr, Mn, Fe, Ni, Cu, Ga, Ge, Se, Nb, Mo, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, Ta, W, Ir, Pt, Au, and Bi. 
     
     
         18 . The layer structure of  claim 15  wherein the metallic material of the underlayer has the fcc lattice structure and wherein the underlayer comprises at least one element from the group consisting of Al, Ni, Cu, Rh, Pd, Ag, Ir, Pt, Au, Pb. 
     
     
         19 . The layer structure of  claim 15  wherein the metallic material of the underlayer has the fcc lattice structure and wherein the underlayer comprises at least one element from the group consisting of Al, Ni, Cu, Rh, Pd, Ag, Ir, Pt, Au, and Pb; and at least one element from the group consisting of B, C, N, O, Na, Si, S, P, K, Sc, Ti, V, Cr, Mn, Fe, Co, Zn, Ga, Ge, Se, Y, Zr, Nb, Mo, Ru, Cd, In, Sn, Sb, Te, Hf, Ta, W, Re, and Bi. . 
     
     
         20 . The layer structure of  claim 15  wherein the metallic material of the underlayer has the bcc lattice structure and wherein the underlayer comprises at least one element from the group consisting of V, Cr, Fe, Nb, Mo, Ta, W.