Mask and method for using the mask in lithographic processing
AssigneeInfineon Technologies AG
InventorsSyed Shoaib Hasan Zaidi, Alois Gutmann, Gary Williams
Life of this patent
Estimating the term…
Abstract
A method and mask to improve measurement of alignment marks is disclosed. An exemplary embodiment of the invention includes a resist mask with a patterned alignment mark comprising an assemblage of features whose spacing is smaller than the wavelength of light used to measure the alignment. In a preferred embodiment, an alignment mark patterning process alters the appearance of the alignment mark and renders an enhanced contrast with the substrate background.
Claims21
A resist mask for measuring alignment on a substrate, the resist mask comprising at least one alignment mark, wherein the alignment mark includes patterned structures arranged as part of the resist mask and having a height that is less than the thickness of an unpatterned resist layer forming the resist mask, and wherein at least some of the pattern structures have a lateral spacing that is smaller than the wavelength of light used for alignment measurement.
A resist mask for measuring alignment on a substrate, the resist mask comprising at least one alignment mark, wherein the alignment mark comprises at least two distinct regions, at least one distinct region formed from a plurality of patterned features arranged as part of the resist mask and having a height that is less than the thickness of an unpatterned resist layer forming the resist mask, and wherein at least some of whose lateral spacing is smaller than the wavelength of light used for alignment measurement.
A resist mask for measuring alignment, the resist mask comprising at least one alignment mark, wherein the alignment mark includes patterned structures at least some of whose lateral spacing is smaller than the wavelength of light used for alignment measurement, and wherein the at least one alignment mark further includes a continuous resist layer upon which the patterned structures are formed.
Dependencies are inferred from the claim text.