Manufacturing method, including near-field optical microscopic examination of a magnetic bit pattern

Claim 1

A method for manufacturing an article, comprising the steps of: a) providing a multiplicity of substrates, each substrate having a surface layer of magnetic material to be impressed with a bit pattern; b) setting at least one process parameter; c) processing at least a first substrate according to the process parameter such that a bit pattern is formed in the surface layer of the substrate; d) sensing the bit pattern in at least the first substrate; e) comparing the sensed bit pattern to a predetermined bit pattern; f) if the sensed bit pattern is different from the predetermined bit pattern, changing the process parameter to bring the sensed and predetermined bit patterns into conformity; g) after (f), processing at least a second substrate according to the process parameter; and h) performing, on at least the second substrate, at least one additional step toward completion of the article. wherein the sensing step comprises the further steps of: i) impinging electromagnetic radiation of at least a given wavelength on the surface layer such that at least a portion of the radiation is reflected from the surface layer; j) admitting a portion of the reflected radiation into a waveguiding body through an aperture that is distant from the surface layer by no more than the given wavelength, and that is smaller, in a least one lateral dimension, than the given wavelength; exciting a guided metallic mode of electromagnetic radiation within the waveguiding body; adiabatically converting a portion of the electromagnetic radiation from the metallic mode to at least one guided dielectric mode; and receiving the adiabatically converted radiation at a photodetector.

Claim 2

A method for manufacturing an article, comprising the steps of: a) providing a multiplicity of substrates, each substrate having a surface layer of magnetic material to be impressed with a bit pattern; b) setting at least one process parameter; c) processing at least a first substrate according to the process parameter such that a bit pattern is formed in the surface layer of the substrate; d) sensing the bit pattern in at least the first substrate; e) comparing the sensed bit pattern to a predetermined bit pattern; f) if the sensed bit pattern is different from the predetermined bit pattern, changing the process parameter to bring the sensed and predetermined bit patterns into conformity; g) after (f), processing at least a second substrate according to the process parameter; and h) performing, on at least the second substrate, at least one additional step toward completion of the article. wherein the sensing step comprises the further steps of: i) impinging electromagnetic radiation of at least a given wavelength on the surface layer such that at least a portion of the radiation is reflected from the surface layer; j) admitting a portion of the reflected radiation into a waveguiding body through an aperture that is distant from the surface layer by no more than the given wavelength, and that is smaller, in a least one lateral dimension, than the given wavelength; exciting a guided metallic mode of electromagnetic radiation within the waveguiding body; adiabatically converting a portion of the electromagnetic radiation from the metallic mode to at least one guided dielectric mode; and receiving the adiabatically converted radiation at a photodetector.

Claim 3

A method for manufacturing an article, comprising the steps of: a) providing a multiplicity of substrates, each substrate having a surface layer of magnetic material to be impressed with a bit pattern; b) setting at least one process parameter; c) processing at least a first substrate according to the process parameter such that a bit pattern is formed in the surface of the substrate; d) sensing the bit pattern in at least the first substrate; e) comparing the sensed bit pattern to a predetermined bit pattern; f) if the sensed bit pattern is different from the predetermined bit pattern, changing the process parameter to bring the sensed and predetermined bit patterns into conformity; g) after (f), processing at least a second substrate according to the process parameter; and h) performing, on at least the second substrate, at least one additional step toward completion of the article. wherein the sensing step comprises the further steps of: i) admitting electromagnetic radiation of at least a given wavelength into an optical waveguiding body such that a guided dielectric mode is excited within the waveguiding body; j) adiabatically converting a portion of the electromagnetic radiation from the guided dielectric mode to a guided metallic mode; k) emitting a portion of the adiabatically converted radiation from an aperture that is distant from the surface layer by no more than the given wavelength, and that is smaller, in a least one lateral dimension, than the given incident wavelength, such that at least some of the emitted radiation is reflected by the surface layer; and l) receiving at least some of the reflected radiation at a photodetector.

Claim 4

A method for manufacturing an article, comprising the steps of: a) providing a multiplicity of substrates, each substrate having a surface layer of magnetic material to be impressed with a bit pattern; b) setting at least one process parameter; c) processing at least a first substrate according to the process parameter such that a bit pattern is formed in the surface of the substrate; d) sensing the bit pattern in at least the first substrate; e) comparing the sensed bit pattern to a predetermined bit pattern; f) if the sensed bit pattern is different from the predetermined bit pattern, changing the process parameter to bring the sensed and predetermined bit patterns into conformity; g) after (f), processing at least a second substrate according to the process parameter; and h) performing, on at least the second substrate, at least one additional step toward completion of the article. wherein the sensing step comprises the further steps of: i) admitting electromagnetic radiation of at least a given wavelength into an optical waveguiding body such that a guided dielectric mode is excited within the waveguiding body; j) adiabatically converting a portion of the electromagnetic radiation from the guided dielectric mode to a guided metallic mode; k) emitting a portion of the adiabatically converted radiation from an aperture that is distant from the surface layer by no more than the given wavelength, and that is smaller, in a least one lateral dimension, than the given incident wavelength, such that at least some of the emitted radiation is reflected by the surface layer; and l) receiving at least some of the reflected radiation at a photodetector.