US 4,377,627 AGranted

Microminiature solid state device manufacture with automatic alignment of sub-patterns

AssigneeU.S. Philips Corporation

InventorDavid J. Vinton

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Abstract

A semiconductor substrate is mounted in an electron beam image projector with a mask. The patterned electron beam from the mask comprises a first sub-pattern and a second lower intensity sub-pattern. The difference in the intensities of the two sub-patterns permits the automatic alignment of the patterned electron beam relative to the substrate by detecting when the first sub-pattern is incident on a reference marker pattern on the substrate, while the first and second sub-patterns together expose an electron sensitive layer at the entire area of the reference marker pattern. The part of the layer retained after developing can be used as an etchant mask during the definition of a protective layer or the removal of unwanted material from the entire area of the reference marker pattern depending on whether the layer is a negative or a positive electron sensitive material.

Claims14

Dependent claims

In a method of manufacturing a microminiature solid state device comprising the step of forming at least one reference marker pattern on a surface of a semiconductor substrate, the improvement comprising the steps of forming said reference marker pattern by

exposing a layer of radiation sensitive material on said surface of said substrate to a patterned radiation beam from a mask, said mask passing a first sub-pattern of radiation and a second sub-pattern of radiation having a lower intensity than said first sub-pattern, said first sub-pattern being contained at least within a portion of said second sub-pattern, and said first sub-pattern having substantially the same configuration as said reference marker pattern,
aligning said patterned radiation beam from said mask relative to said substrate so that said first sub-pattern is incident on said reference marker pattern, and
continuing exposure of said layer to determine a portion of said layer for removal, said layer being defined by the perimeter of said patterned radiation beam.

Dependencies are inferred from the claim text.