Synthesis of silicon containing materials using liquid hydrosilane compositions through direct injection
An apparatus and a non-vapor-pressure dependent method of chemical vapor deposition of Si based materials using direct injection of liquid hydrosilane(s) are presented. Liquid silane precursor solutions may also include metal, non-metal or metalloid dopants, nanomaterials and solvents. An illustrative apparatus has a precursor solution and carrier gas system, atomizer and deposit head with interior chamber and a hot plate supporting the substrate. Atomized liquid silane precursor solutions and carrier gas moves through a confined reaction zone that may be heated and the aerosol and vapor are deposited on a substrate to form a thin film. The substrate may be heated prior to deposition. The deposited film may be processed further with thermal or laser processing.
1. A method for synthesizing silicon thin films, comprising:
atomizing a liquid silane to form an aerosol;
heating the aerosol and a carrier gas to produce heated aerosol and vapor;
depositing the heated aerosol and vapor onto a substrate to form a deposited film; and
transforming the deposited film.
2. A method as recited in claim 1 , further comprising heating the substrate to a temperature between about 300° C. to 500° C. prior to depositing the heated aerosol on the substrate.
3. A method as recited in claim 1 , wherein said heating of liquid silane aerosol comprises heating the aerosol to a temperature between about 150° C. and 250° C.
4. A method as recited in claim 1 , wherein said liquid silane is a silane selected from the group of silanes consisting of hydrosilanes of the formula Si n H 2n , Si n H 2n+2 and (—Si—) n , where n is a number between 3 and 20.
5. A method as recited in claim 1 , wherein said liquid silane further comprises a solvent selected from the group of solvents consisting of toluene, xylene, cyclooctane, 1,2,4-trichlorobenzene, dichloromethane and mixtures thereof.
6. A method as recited in claim 1 , wherein said liquid silane further comprises a dopant containing an element selected from the group of elements consisting of Ti, V, Cr Mn, Fe, Co, Ni, Zn, Ga, Ge, As, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, TI, Pb, Bi, Al, Si, P, and B.
7. A method as recited in claim 1 , wherein the deposited film is transformed using thermal processing at a temperature from about 150° C. to 300° C. to produce a polysilane-containing film.
8. The method recited in claim 1 , wherein the deposited film is transformed using thermal processing at temperatures from about 300° C. to 700° C. to produce amorphous silicon-containing materials.
9. The method as recited in claim 1 , wherein the deposited film is transformed using thermal processing at temperatures from about 700° C. to 1200° C. to produce crystalline silicon-containing materials.