Micron Technology Incorporated

Eugene A DeLaRosa

William Arthur Stanton

Troy V Gugel

A method and apparatus for measuring registration between two or more integrated circuit layers is disclosed. Images of actual operative circuitry of different layers of a semiconductor wafer, obtained by an optical technique or a scanning electron microscope, are digitized and analyzed for the relative placement of pattern shapes of the corresponding layers. This relative placement is then compared to tolerance values and if out of tolerance misregistration of the two layers is indicated.

Method for measuring registration of overlapping material layers of an integrated circuit

The present invention is generally directed to various reticle writing methodologies to reduce write time, and a system for performing same. In one illustrative embodiment, the method comprises exposing a layer of photoresist in accordance with a first writing pattern in a first area of the layer of photoresist and exposing the layer of photoresist in accordance with a second writing pattern in a second area of the layer of photoresist, the first and second areas of the layer of photoresist overlapping one another in at least one region. In another illustrative embodiment, the method comprises creating a collection of digital data corresponding to a desired pattern for a reticle and separating the collection of digital data into at least two separate groups of data, a first of the data groups being used to define a first writing pattern for the reticle, a second of the data groups being used to define a second writing pattern for the reticle, wherein the first and second writing patterns overlap one another in at least one region. In yet another illustrative embodiment, the method comprises forming a layer of photoresist above at least one of a semiconducting substrate and a process layer, exposing the layer of photoresist in accordance with a first writing pattern in a first area of the layer of photoresist, and exposing the layer of photoresist in accordance with a second writing pattern in a second area of the layer of photoresist, wherein the first and second areas overlap one another in at least one region.

Writing methodology to reduce write time, and system for performing same

A multiple pass write method and a reticle made from the method are described. A reticle preform is provided including a transparent substrate, a metal layer, and a layer of a photoresist material. In a first write pass, a first portion of the photoresist material is exposed by an electron beam device. Then, in a second write pass, a second portion of the photoresist material is exposed. The first exposed portion is smaller or has finer dimensions than the second exposed portion. The exposed portions of photoresist material are removed, and the unexposed portions of photoresist serve as a mask. The uncovered portions of the conductive layer are etched. Further, the unexposed portions of the photoresist material are removed, creating a reticle through a multiple write pass strategy.

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Boise, ID, United States of America

Eugene A DeLaRosa