Method of cleaning and forming a negatively charged passivation layer over a doped region
AssigneeApplied Materials, Inc.
InventorsMichael P. Stewart, Lisong Zhou, Jen Shu, Li (Sherry) Xu
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Abstract
The present invention generally provides a method of forming a high efficiency solar cell device by preparing a surface and/or forming at least a part of a high quality passivation layer on a silicon containing substrate. Embodiments of the present invention may be especially useful for preparing a surface of a p-type doped region formed on a silicon substrate so that a high quality passivation layer can be formed thereon. In one embodiment, the methods include exposing a surface of the solar cell substrate to a plasma to clean and modify the physical, chemical and/or electrical characteristics of the surface.
Claims15
A method of passivating a surface a solar cell substrate, comprising:
- exposing a surface of a p-type doped region formed on a substrate to a first RF plasma that comprises a first processing gas and a first fluorine containing gas;
- exposing the surface of the p-type doped region to a second RF plasma that comprises a halogen gas;
- and
- RF biasing the substrate, during at least a portion of the exposing the surface to the second RF plasma, to form a negatively charged layer on the surface.
A method of passivating a surface a solar cell substrate, comprising:
- exposing a surface of a p-type doped region formed on an n-type substrate to a first RF plasma that comprises a first processing gas and a first fluorine containing gas;
- exposing the surface of the p-type doped region to a second RF plasma that comprises a second processing gas, a second fluorine containing gas and hydrogen containing gas;
- exposing the surface of the p-type doped region to a third RF plasma that comprises a halogen gas;
- RF biasing the substrate, during at least a portion of the exposing the surface to the third RF plasma, to form a negatively charged layer on the surface of the p-type doped region;
- and
- depositing a first silicon nitride-containing layer on the formed negatively charged layer.
Dependencies are inferred from the claim text.