Methods of forming capping layers on reflective materials
AssigneesInfineon Technologies AG, Freescale Semiconductor, Inc.
InventorsStefan Wurm, Nora V. Edwards
Life of this patent
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Abstract
A reflective material is heated to reduce internal stress, and then a capping layer is formed over the reflective material. Heating the reflective material reduces the internal stress of the reflective material. Because the reflective material has reduced internal stress, a more continuous, stable and reliable capping layer is formed that is not subject to stress induced degradation over time due to the relaxing internal stress of the underlying reflective material. Thus, the capping layer remains intact and protects the reflective material residing beneath the capping layer from exposure to contaminants.
Claims25
A method of forming a capping layer over a multi-layer mirror element, the method comprising:
- providing the multi-layer mirror element, at least a top portion of the multi-layer mirror element having internal stress;
- heating at least the multi-layer mirror element, thereby reducing the internal stress of at least the top portion of the multi-layer mirror element;
- and
- forming the capping layer over the multi-layer mirror element.
A method of manufacturing a multi-layer mirror element, the method comprising:
- providing a substrate;
- forming a plurality of material layers over the substrate, the plurality of material layers comprising a first internal stress;
- heating at least the plurality of material layers to reduce the first internal stress;
- and
- forming a capping layer over the plurality of material layers.
A method of manufacturing a multi-layer mirror element of an extreme ultraviolet lithography (EUVL) system, the method comprising:
- providing a substrate;
- placing the substrate in a deposition chamber;
- forming a plurality of material layers over the substrate, the plurality of material layers comprising a first internal stress;
- heating at least the plurality of material layers, reducing the first internal stress;
- and
- forming a capping layer over the plurality of material layers, wherein forming the plurality of material layers, heating at least the plurality of material layers, and forming the capping layer are performed in the deposition chamber without removing the substrate from the deposition chamber.
Dependencies are inferred from the claim text.