Amorphous tin-cadmium oxide films and the production thereof
A tin-cadmium oxide film having an amorphous structure and a ratio of tin atoms to cadmium atoms of between 1:1 and 3:1. The tin-cadmium oxide film may have an optical band gap of between 2.7 eV and 3.35 eV. The film may also have a charge carrier concentration of between 1×10 20 cm −3 and 2×10 20 cm −3 . The tin cadmium oxide film may also exhibit a Hall mobility of between 40 cm 2 V −1 s −1 and 60 cm 2 V −1 s −1 . Also disclosed is a method of producing an amorphous tin-cadmium oxide film as described and devices using same.
1. A method of producing a tin-cadmium oxide film comprising:
introducing a tin precursor in a carrier gas into a low pressure deposition chamber having a chamber temperature of between 500° C. and 550° C.;
introducing a cadmium precursor in a carrier gas into the low pressure deposition chamber;
introducing oxygen into the low pressure deposition chamber; and
depositing a tin-cadmium oxide material onto a substrate wherein the tin-cadmium oxide material comprises an amorphous structure and a ratio of tin atoms to cadmium atoms of between 1:1 and 3:1.
2. The method of producing a tin-cadmium oxide film of claim 1 further comprising mixing the cadmium precursor, tin precursor and oxygen with a carrier gas before introducing the resulting precursor mixture into the low pressure deposition chamber.
3. The method of producing a tin-cadmium oxide film of claim 2 wherein the tin precursor comprises tetramethyltin.
4. The method of producing a tin-cadmium oxide film of claim 3 wherein the cadmium precursor comprises dimethylcadmium.
5. The method of producing a tin-cadmium oxide film of claim 4 wherein the ratio of tetramethyltin to dimethylcadmium in the precursor mixture is between 0.5:1 and 5:1.
6. The method of producing a tin-cadmium oxide film of claim 1 further comprising depositing the tin-cadmium oxide material with a metalorganic chemical vapor deposition technique.
7. The method of producing a tin-cadmium oxide film of claim 1 further comprising depositing the tin-cadmium oxide material on a glass substrate.
8. The method of producing a tin-cadmium oxide film of claim 1 wherein the deposited tin-cadmium oxide material has an optical bandgap of between 2.7 eV and 3.35 eV.
9. The method of producing a tin-cadmium oxide film of claim 1 wherein the deposited tin-cadmium oxide material has a charge carrier concentration of between 1×10 20 cm −3 and 2×10 20 cm −3 .
10. The method of producing a tin-cadmium oxide film of claim 1 wherein the deposited tin-cadmium oxide material exhibits a Hall mobility of between 40 cm 2 V −1 s −1 and 60 cm 2 V −1 s −1 .