Surface composite film structure with longitudinal transmission cutoff and transverse transmission conduction, and preparation method and application thereof
A surface composite film structure with longitudinal transmission cutoff and transverse transmission conduction, and a preparation method and application thereof are provided. The surface composite film structure includes a nano dielectric layer arranged on a surface of a silicon substrate, a silicide layer arranged on the nano dielectric layer and a polycrystalline silicon layer arranged on the silicide layer. A material of the nano dielectric layer is a hydrogenated silicon oxide film, a material of the silicide layer is a hydrogenated carbon nitride silicon film including phosphorus or boron, and a material of the polycrystalline silicon layer is a phosphorus-doped or boron-doped polycrystalline silicon film. The surface composite film structure can achieve an excellent passivation effect and has the characteristics of longitudinal non-conduction and transverse conduction, and the transverse sheet resistance is flexibly adjustable, meeting the performance requirements of new silicon-based semiconductor physical devices.
1. A surface composite film structure with longitudinal transmission cutoff and transverse transmission conduction, comprising a nano dielectric layer arranged on a surface of a silicon substrate, a silicide layer arranged on the nano dielectric layer and a polycrystalline silicon layer arranged on the silicide layer, wherein a material of the nano dielectric layer is a hydrogenated silicon oxide film, a material of the silicide layer is a hydrogenated carbon nitride silicon film comprising phosphorus or boron, and a material of the polycrystalline silicon layer is a phosphorus-doped polycrystalline silicon film or a boron-doped polycrystalline silicon film.
2. The surface composite film structure according to claim 1 , wherein a refractive index of the silicide layer is 1.5-3.0, and a transmittance of the silicide layer above 400 nm is greater than 97%.
3. The surface composite film structure according to claim 2 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
4. The surface composite film structure according to claim 1 , wherein a carbon concentration of the silicide layer is 1×10 21 cm −3 -2×10 22 cm −3 , and a nitrogen concentration of the silicide layer is 5×10 21 cm −3 -4×10 22 cm −3 .
5. The surface composite film structure according to claim 4 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
6. The surface composite film structure according to claim 1 , wherein a phosphorus or boron concentration of the silicide layer is 1×10 19 cm −3 -1×10 21 cm −3 .
7. The surface composite film structure according to claim 6 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
8. The surface composite film structure according to claim 1 , wherein a thickness of the nano dielectric layer is 1-20 nm, and a thickness of the silicide layer is greater than 10 nm.
9. The surface composite film structure according to claim 8 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
10. The surface composite film structure according to claim 1 , wherein a hydrogen concentration of the nano dielectric layer is 1×10 19 cm −3 -1×10 22 cm −3 , and a hydrogen concentration of the silicide layer is 1×10 19 cm −3 -1×10 22 cm −3 .
11. The surface composite film structure according to claim 10 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
12. The surface composite film structure according to claim 1 , wherein the material of the polycrystalline silicon layer is the phosphorus-doped polycrystalline silicon film with an activation concentration range of 1×10 19 cm −3 -1×10 21 cm −3 , or the material of the polycrystalline silicon layer is the boron-doped polycrystalline silicon film with an activation concentration range of 5×10 18 cm −3 -5×10 20 cm −3 .
13. The surface composite film structure according to claim 12 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
14. The surface composite film structure according to claim 1 , wherein the silicon substrate comprises hydrogen element, carbon element and nitrogen element, and a concentration of each element of the hydrogen element, the carbon element and the nitrogen element gradually decreases from the surface of the silicon substrate to a body of the silicon substrate; and the surface of the silicon substrate comprises a hydrogen concentration of 1×10 19 cm −3 -1×10 21 cm −3 , a nitrogen concentration of 1×10 19 cm −3 -1×10 22 cm −3 , and a carbon concentration of 1×10 19 cm −3 -1×10 22 cm −3 .
15. The surface composite film structure according to claim 14 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
16. The surface composite film structure according to claim 1 , wherein a hydrogen-rich dielectric layer is provided between the silicide layer and the polycrystalline silicon layer, and a material of the hydrogen-rich dielectric layer is one or a laminated film of more selected from hydrogenated aluminum oxide film, hydrogenated silicon nitride film, hydrogenated silicon nitride oxide film and the hydrogenated silicon oxide film.
17. A preparation method of the surface composite film structure according to claim 1 , comprising the following steps:
S 1 , cleaning the silicon substrate;
S 2 , preparing a silicon oxide film on the surface of the silicon substrate;
S 3 , depositing an amorphous silicon film comprising carbon element and nitrogen element;
S 4 , depositing an amorphous silicon film doped with the phosphorus or the boron;
S 5 , performing a high-temperature annealing treatment to diffuse the carbon element and the nitrogen element into the silicon substrate and transforming the amorphous silicon film doped with the phosphorus or the boron into a polycrystalline silicon film; and
S 6 , performing a hydrogenation treatment.
18. The preparation method according to claim 17 , wherein between the step S 2 and the step S 3 , the preparation method comprises a step of depositing one or a laminated film of more selected from aluminum oxide, silicon nitride, silicon oxide and silicon nitride oxide.
19. The preparation method according to claim 17 , wherein in the surface composite film structure, a refractive index of the silicide layer is 1.5-3.0, and a transmittance of the silicide layer above 400 nm is greater than 97%.
20. A silicon-based semiconductor device, comprising the surface composite film structure according to claim 1 .