Electromigration method for making stained glass photomasks

Claim 1

A method for making a stained glass photomask having improved resolution comprising: applying to a first surface of a glass substrate a layer of a source of stain-producing cations; applying onto said cation source layer a layer of organic photoresist; placing a master mask over the photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying a first electrode layer onto the organic photoresist layer and into contact with the portions of the cation source layer exposed by the apertures in the photoresist layer, and applying a second electrode layer onto the glass surface on the opposite side of the glass substrate from said first surface; simultaneously heating the coated composite consisting essentially of the glass substrate, the source layer of stain-producing cations, the apertured organic photoresist layer, and the electrode layers to at least 100° C. while applying a direct current electric field between said first and second electrodes, with the first electrode as anode and the second electrode as cathode, so that electric charge passes through the apertures in the organic photoresist layer and induces migration of stain-producing cations from the cation source layer into portions of the glass underlying said apertures, and passage of electric charge is blocked by the organic photoresist layer so that the areas of the glass underlying the organic photoresist remain substantially free from migrated stain-producing cations; removing said electrode layers, organic photoresist layers, and cation source layer from the glass substrate, and heating the glass in the presence of a reducing agent so as to reduce and agglomerate the migrated stain-producing cations within the glass, thereby producing a stained pattern within the surface of the glass.

Claim 2

A method for making a stained glass photomask having improved resolution comprising: applying to a first surface of a glass substrate a layer of a source of stain-producing cations; applying onto said cation source layer a layer of organic photoresist; placing a master mask over the photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying a first electrode layer onto the organic photoresist layer and into contact with the portions of the cation source layer exposed by the apertures in the photoresist layer, and applying a second electrode layer onto the glass surface on the opposite side of the glass substrate from said first surface; simultaneously heating the coated composite consisting essentially of the glass substrate, the source layer of stain-producing cations, the apertured organic photoresist layer, and the electrode layers to at least 100° C. while applying a direct current electric field between said first and second electrodes, with the first electrode as anode and the second electrode as cathode, so that electric charge passes through the apertures in the organic photoresist layer and induces migration of stain-producing cations from the cation source layer into portions of the glass underlying said apertures, and passage of electric charge is blocked by the organic photoresist layer so that the areas of the glass underlying the organic photoresist remain substantially free from migrated stain-producing cations; removing said electrode layers, organic photoresist layers, and cation source layer from the glass substrate, and heating the glass in the presence of a reducing agent so as to reduce and agglomerate the migrated stain-producing cations within the glass, thereby producing a stained pattern within the surface of the glass.

Claim 15

A method for making a stained glass photomask having improved resolution comprising: applying onto a first surface of a glass substrate a layer of organic photoresist; placing a master mask over the organic photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying onto said apertured organic photoresist layer and into the apertures therein, a layer of a source of stain-producing cations; applying an electrode layer onto the glass surface on the opposite side of the glass substrate from said first surface; connecting said electrode layer to the cathode side of a source of electrical potential and said cation source layer to the anode side of a source of electrical potential and simultaneously heating the coated composite consisting essentially of the glass substrate, the source layer of stain-producing cations, the apertured organic photoresist layer, and the electrode layer to at least 100° C. while applying a direct current electric field between said cation source layer and the electrode layer, so that electric charge passes through the apertures in the organic photoresist and induces migration of stain-producing cations from the cation source layer into portions of the glass underlying said apertures, and passage of electric charge is blocked by the organic photoresist layer so that the areas of the glass underlying the organic photoresist remain substantially free from migrated stain-producing cations; removing said electrode layer, organic photoresist layer, and cation source layer from the glass substrate; and heating the glass, in the presence of a reducing agent so as to reduce and agglomerate the migrated stain-producing cations within the glass, thereby producing a stained pattern within the surface of the glass.

Claim 16

A method for making a stained glass photomask having improved resolution comprising: applying onto a first surface of a glass substrate a layer of organic photoresist; placing a master mask over the organic photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying onto said apertured organic photoresist layer and into the apertures therein, a layer of a source of stain-producing cations; applying an electrode layer onto the glass surface on the opposite side of the glass substrate from said first surface; connecting said electrode layer to the cathode side of a source of electrical potential and said cation source layer to the anode side of a source of electrical potential and simultaneously heating the coated composite consisting essentially of the glass substrate, the source layer of stain-producing cations, the apertured organic photoresist layer, and the electrode layer to at least 100° C. while applying a direct current electric field between said cation source layer and the electrode layer, so that electric charge passes through the apertures in the organic photoresist and induces migration of stain-producing cations from the cation source layer into portions of the glass underlying said apertures, and passage of electric charge is blocked by the organic photoresist layer so that the areas of the glass underlying the organic photoresist remain substantially free from migrated stain-producing cations; removing said electrode layer, organic photoresist layer, and cation source layer from the glass substrate; and heating the glass, in the presence of a reducing agent so as to reduce and agglomerate the migrated stain-producing cations within the glass, thereby producing a stained pattern within the surface of the glass.

Claim 30

A method for making a stained glass photomask having improved resolution comprising: applying a layer of a source of stain-producing cations onto a first surface of a glass substrate; uniformly migrating stain-producing cations from said cation source layer into the first surface of the substrate to a first depth while heating the glass; removing the cation source layer from the glass surface; applying a layer of organic photoresist over the ion-injected first surface of the glass; placing a master mask over the photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying a first electrode layer over the organic photoresist layer and the apertures therein and applying a second electrode layer onto the glass surface on the opposite side of the glass substrate from said first surface; simultaneously heating the composite consisting essentially of the glass substrate, the apertured organic photoresist layer, and the electrode layers to at least 100° C. while applying a direct current electric field between said first and second electrodes, with the first electrode as anode and the second electrode as cathode, so that electric charge passes through the apertures in the organic photoresist layer and induces migration of stain-producing cations within the glass from said first depth deeper into the glass to a second depth in the portions of the glass underlying the apertures in the photoresist, and passage of electric charge is blocked by the organic photoresist layer so that substantially no additional migration of stain-producing ions beyond said first depth takes place in the portions of the glass underlying the organic photoresist; removing the electrode layers and the photoresist layer from the glass surfaces; and heating the substrate in the presence of a reducing agent so as to reduce and agglomerate the stain-producing ions within the glass above said first depth, and discontinuing the reduction before stain-producing ions deeper within the glass than said first depth become reduced, thereby producing a stained pattern within the glass.

Claim 31

A method for making a stained glass photomask having improved resolution comprising: applying a layer of a source of stain-producing cations onto a first surface of a glass substrate; uniformly migrating stain-producing cations from said cation source layer into the first surface of the substrate to a first depth while heating the glass; removing the cation source layer from the glass surface; applying a layer of organic photoresist over the ion-injected first surface of the glass; placing a master mask over the photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying a first electrode layer over the organic photoresist layer and the apertures therein and applying a second electrode layer onto the glass surface on the opposite side of the glass substrate from said first surface; simultaneously heating the composite consisting essentially of the glass substrate, the apertured organic photoresist layer, and the electrode layers to at least 100° C. while applying a direct current electric field between said first and second electrodes, with the first electrode as anode and the second electrode as cathode, so that electric charge passes through the apertures in the organic photoresist layer and induces migration of stain-producing cations within the glass from said first depth deeper into the glass to a second depth in the portions of the glass underlying the apertures in the photoresist, and passage of electric charge is blocked by the organic photoresist layer so that substantially no additional migration of stain-producing ions beyond said first depth takes place in the portions of the glass underlying the organic photoresist; removing the electrode layers and the photoresist layer from the glass surfaces; and heating the substrate in the presence of a reducing agent so as to reduce and agglomerate the stain-producing ions within the glass above said first depth, and discontinuing the reduction before stain-producing ions deeper within the glass than said first depth become reduced, thereby producing a stained pattern within the glass.

Claim 45

A method for making a stained glass photomask comprising: applying a layer of organic photoresist over a first surface of a sheet of glass; placing a master mask over the photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying a layer of molten salt containing stain-producing cations onto the photoresist and into contact with portions of the glass through said apertures in the photoresist and maintaining the composite consisting essentially of the glass substrate, the apertured organic photoresist, and the molten salt at an elevated temperature so as to induce migration of stain-producing cations from the molten salt into portions of the glass underlying said apertures; removing the molten salt and the photoresist from the glass surface; and heating the glass in the presence of a reducing agent so as to reduce and agglomerate the stain-producing ions migrated within the glass so as to form a stained pattern within the glass.

Claim 46

A method for making a stained glass photomask comprising: applying a layer of organic photoresist over a first surface of a sheet of glass; placing a master mask over the photoresist layer, exposing patterned areas of the photoresist to actinic radiation through the master mask, and photographically developing the exposed photoresist, thereby producing a pattern of apertures through the organic photoresist layer; applying a layer of molten salt containing stain-producing cations onto the photoresist and into contact with portions of the glass through said apertures in the photoresist and maintaining the composite consisting essentially of the glass substrate, the apertured organic photoresist, and the molten salt at an elevated temperature so as to induce migration of stain-producing cations from the molten salt into portions of the glass underlying said apertures; removing the molten salt and the photoresist from the glass surface; and heating the glass in the presence of a reducing agent so as to reduce and agglomerate the stain-producing ions migrated within the glass so as to form a stained pattern within the glass.