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US 4,537,851 AGranted
Process of forming powder pattern using positive diazonium salt photoresist
AssigneeHitachi, Ltd.
InventorsSaburo Nonogaki, Nobuaki Hayashi, Yoshifumi Tomita
Life of this patent
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Abstract
A water-soluble, positive-working photoresist composition is disclosed which comprises water-soluble aromatic diazonium salt, water-soluble phenolic compound, and water-soluble polymeric compound. When the film of this composition is irradiated with a pattern of actinic ray and then brought into contact with an alkaline gas or solution, the coating of unexposed areas hardens to become water-insoluble. Preferably, when the film is brought into contact with a suspension of powder or dry powder after being hardened, a positive pattern of powder is obtained by the development with water.
Claims44
A process for forming a powder pattern using a positive-working photoresist, which comprises:
- (1) applying a water-soluble, positive-working photoresist composition comprising an admixture of water-soluble aromatic diazonium salt, water soluble phenolic compound, and water-soluble polymeric compound, on a substrate to form a positive-working photoresist film, said composition having sufficient concentration of water-soluble aromatic diazonium salt and phenolic compound, and polymeric compound, such that, upon later contact of the photoresist film with alkaline gas or solution, areas of the film can be rendered at most only sparingly water-soluble;
- (2) exposing the applied film to a prescribed pattern of actinic ray to decompose the diazonium salt in exposed areas;
- (3) contacting the resultant exposed film with an alkaline gas or solution to cause a reaction of the diazonium salt with the phenolic compound in unexposed areas to render the unexposed areas of the film at most only sparingly water-soluble, to form a treated film, said alkaline gas or solution having a sufficient concentration so as to make the unexposed area of the film sufficiently uniformly at most only sparingly water-soluble so as to dissolve only exposed areas of the film upon development;
- (4) developing the film, having been contacted with the alkaline gas or solution, with water to remove the film in exposed areas and form a positive-working resist image having a powder pattern;
- and
- (5) contacting a powder with the film to adhere thereto, the contacting with a powder being performed at any time after said applying a water-soluble, positive-working photoresist composition, up to being performed simultaneously with said developing;
- whereby fogging of the powder pattern on the substrate using a positive-working photoresist is avoided.
4 more elements
A process of forming a powder pattern using a positive-working photoresist, which comprises:
- (1) a first step of applying a water-soluble, positive-working photoresist composition comprising an admixture of water-soluble aromatic diazonium salt, water soluble phenolic compound, and water-soluble polymeric compound, on a substrate to form a positive-working photoresist film, said composition having sufficient concentration of water-soluble aromatic diazonium salt and phenolic compound, and polymeric compound, such that, upon later contact of the photoresist film with alkaline gas or solution, areas of the film can be rendered at most only sparingly water-soluble;
- (2) a second step of exposing said film to a prescribed pattern of actinic ray to decompose the diazonium salt in exposed areas;
- (3) a third step of contacting a substantially dry powder with the film to adhere thereto;
- (4) a fourth step of contacting the resultant exposed film with an alkaline gas or solution to cause a reaction of the diazonium salt with the phenolic compound in unexposed areas to render the unexposed areas of the film at most only sparingly water-soluble, to form a treated film, said alkaline gas or solution having a sufficient concentration so as to make the unexposed areas of the film sufficiently uniformly at most only sparingly water-soluble so as to dissolve only exposed areas of the film upon development, wherein said third step is performed after the second step of exposing the film but prior to said fourth step of contacting the resultant exposed film with an alkaline gas or solution;
- (5) a fifth step of developing the treated film with water to remove the film in exposed areas and form a positive-working resist image having a powder pattern,
- whereby fogging of the powder pattern on the substrate using a positive-working photoresist is avoided.
3 more elements
A process of forming a powder pattern using a positive-working photoresist, which comprises:
- (1) a first step of applying a water-soluble, positive-working photoresist composition comprising an admixture of water-soluble aromatic diazonium salt, water-soluble phenolic compound, and water-soluble polymeric compound, on a substrate to form a positive-working photoresist film, said composition having sufficient concentration of water-soluble aromatic diazonium salt and phenolic compound, and polymeric compound, such that, upon later contact of the photoresist film with alkaline gas or solution, areas of the film can be rendered at most only sparingly water-soluble;
- (2) a second step of contacting a substantially dry powder with the film to adhere thereto a layer of dry powder having such a thickness that light is transmitted therethrough in the following, third, step;
- (3) a third step of exposing the film to a prescribed pattern of actinic ray to decompose the diazonium salt in exposed areas;
- (4) a fourth step of contacting the resultant exposed film with an alkaline gas or solution to cause a reaction of the diazonium salt with the phenolic compound in unexposed areas to render the unexposed areas of the film at most only sparingly water-soluble, to form a treated film, said alkaline gas or solution having a sufficient concentration so as to make the unexposed areas of the film sufficiently uniformly at most only sparingly water-soluble so as to dissolve only exposed areas of the film upon development;
- and
- (5) a fifth step of developing the treated film with water to remove the film in exposed areas and form a positive-working resist image having a powder pattern,
- whereby fogging of the powder pattern on the substrate using a positive-working photoresist is avoided.
4 more elements
A process for forming a powder pattern using a positive-working photoresist, which comprises:
- (1) a first step of applying a water-soluble, positive-working photoresist composition comprising an admixture of water-soluble aromatic diazomium salt, water-soluble phenolic compound and water-soluble polymeric compound, on a substrate to form a positive-working photoresist film, said film composition having sufficient concentration of water-soluble aromatic diazonium salt and phenolic compound, and polymeric compound, such that, upon later contact of the photoresist film with alkaline gas or solution, areas of the film can be rendered at most only sparingly water-soluble;
- (2) a second step of exposing said film to a prescribed pattern of actinic ray to decompose the diazonium salt in exposed areas;
- (3) a third step of contacting the resulting exposed film with an alkaline gas or solution to cause a reaction of the diazonium salt with the phenolic compound in unexposed areas to render the unexposed areas of the film at most only sparingly water-soluble, to form a treated film, said alkaline gas or solution having a sufficient concentration so as to make the unexposed areas of the film sufficiently uniformly at most only sparingly water-soluble so as to dissolve only exposed areas of the film upon development, and wherein this third step further involves a step of contacting a powder with the film to adhere thereto;
- and
- (4) a fourth step of developing the treated film with water to remove the film in exposed areas and form a positive-working resist image having a powder pattern,
- whereby fogging of the powder pattern on the substrate using a positive-working photoresist is avoided.
3 more elements
A process of forming a powder pattern using a positive-working photoresist, which comprises:
- (1) a first step of applying a water-soluble positive-working photoresist composition comprising an admixture of water-soluble aromatic diazonium salt, water-soluble phenolic compound, and water-soluble polymeric compound, on a substrate to form a positive-working photoresist film, said composition having sufficient concentration of water-soluble aromatic diazonium salt and phenolic compound, and polymeric compound, such that, upon later contact of the photoresist film with alkaline gas or solution, areas of the film can be rendered at most only sparingly water-soluble;
- (2) a second step of exposing said film to a prescribed pattern of actinic ray to decompose the diazonium salt in exposed areas;
- (3) a third step of contacting the resultant exposed film with an alkaline gas or solution to cause a reaction of the diazonium salt with the phenolic compound in unexposed areas to render the unexposed areas of the film at most only sparingly water-soluble, to form a treated film, said alkaline gas or solution having a sufficient concentration so as to make the unexposed areas of the film sufficiently uniformly to most only sparingly water-soluble so as to dissolve only exposed areas of the film upon development;
- (4) a fourth step of contacting a powder with the treated film to adhere thereto, said fourth step being performed prior to or during developing the treated film;
- and
- (5) a fifth step of developing the treated film with water to remove the film in exposed areas and form a positive-working resist image having a powder pattern,
- whereby fogging of the powder pattern on the substrate using a positive-working photoresist is avoided.
4 more elements
Dependencies are inferred from the claim text.