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US5773198A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of forming high resolution circuitry by depositing a polyvinyl alcohol layer beneath a photosensitive polymer layer

Assignee: Motorola Solutions Inc
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Filing: 1996-06-07
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Granted: 1998-06-30
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Expires: 2016-06-07
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Abstract

Abstract A method of forming a high resolution metal pattern on a substrate. A temporary polyvinyl alcohol (10) layer underneath the photoresist layer (20) aids in removing the photoresist layer after plating. The photoresist is photodelineated in conventional manner to form a pattern (40). During photodelineation, the developing process for the resist does not completely remove the PVA (45) that lies directly under the removed resist, but instead reveals those portions of the polyvinyl alcohol layer. The substrate is then rinsed in a hot aqueous solution to effect removal of the revealed PVA portions, now exposing portions (40) of the substrate (15). Metal (50) is then electroplated to build up a metal circuitry pattern. The remaining portions of the photoresist and the PVA are then removed by a hot aqueous solution.

Inventors

  • 👤 Thomas J. Swirbel
  • 👤 Anthony B. Suppelsa
  • 👤 Joaquin Barreto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 21:49
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/10; H05K3/108; G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/092; H05K2203/00; H05K2203/05; H05K2203/0562; H05K2203/0577; H05K2203/07; H05K2203/0779; H05K2203/0786; H05K2203/0789; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/95; Y10S438/951

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 114 words
A method of forming high resolution circuitry, comprising: depositing a thin polyvinyl alcohol layer on a substrate; depositing a photosensitive polymer layer on top of the thin polyvinyl alcohol layer; photodelineating a pattern in the deposited photosensitive polymer layer to reveal portions of the thin polyvinyl alcohol layer; rinsing the revealed portions in a first hot aqueous solution to effect removal of the revealed portions, thereby exposing portions of the substrate; electroplating metal into the photodelineated pattern and onto the exposed portions of the substrate to create a circuitry pattern; and removing the remaining portions of the photosensitive polymer layer and the thin polyvinyl alcohol layer by means of a second hot aqueous solution.
Claim 2
Independent Claim 114 words
A method of forming high resolution circuitry, comprising: depositing a thin polyvinyl alcohol layer on a substrate; depositing a photosensitive polymer layer on top of the thin polyvinyl alcohol layer; photodelineating a pattern in the deposited photosensitive polymer layer to reveal portions of the thin polyvinyl alcohol layer; rinsing the revealed portions in a first hot aqueous solution to effect removal of the revealed portions, thereby exposing portions of the substrate; electroplating metal into the photodelineated pattern and onto the exposed portions of the substrate to create a circuitry pattern; and removing the remaining portions of the photosensitive polymer layer and the thin polyvinyl alcohol layer by means of a second hot aqueous solution.
Claim 3
Dependent Claim 17 words
The method of claim 1, wherein the first hot aqueous solution comprises water or preplate microetch cleaners.
Claim 4
Dependent Claim 15 words
The method of claim 1, wherein the second hot aqueous solution comprises an alkaline solution.
Claim 5
Dependent Claim 17 words
The method of claim 1, wherein the substrate has a metal seed layer overlying the substrate surface.
Claim 6
Dependent Claim 29 words
The method of claim 1, wherein the step of depositing a thin layer of polyvinyl alcohol further comprises drying the thin polyvinyl alcohol layer at 50°-100° C. after depositing.
Claim 7
Dependent Claim 24 words
The method of claim 1, further comprising a step, between the step of rinsing and the step of electroplating, of baking at 100°-140° C.
Claim 8
Dependent Claim 32 words
The method of claim 1, wherein the step of photodelineating a pattern comprises exposing portions of the photosensitive polymer layer to actinic light and developing photosensitive polymer layer in an alkaline solution.
Claim 9
Dependent Claim 26 words
The method of claim 1, wherein a portion of the pattern comprises a cross sectional structure having a height equal to or greater than a width.
Claim 10
Dependent Claim 25 words
The method of claim 1, wherein spacing between adjacent traces in the circuitry pattern is equal to or less than the width of the traces.
Claim 11
Independent Claim 170 words
A method of forming high resolution metal circuitry on a substrate, comprising: providing a substrate having a metal seed layer overlying a major surface; depositing a thin polyvinyl alcohol layer on a substrate; drying the thin polyvinyl alcohol layer at 50°-100° C.; depositing a photosensitive polymer layer on top of the thin polyvinyl alcohol layer; exposing portions of the photosensitive polymer layer to actinic light and then developing the photosensitive polymer layer in an alkaline solution in order to photodelineate a pattern in the photosensitive polymer layer, so as to reveal portions of the underlying thin polyvinyl alcohol layer; rinsing the revealed portions in a heated water or preplate microetch solution to effect removal of the revealed portions, thereby exposing portions of the substrate; baking at 100°-140° C.; electroplating metal into the photodelineated pattern and onto the exposed portions of the substrate to create a circuitry pattern; and removing the remaining portions of the photosensitive polymer layer and the thin polyvinyl alcohol layer by immersing in a heated alkaline solution.
Claim 12
Independent Claim 170 words
A method of forming high resolution metal circuitry on a substrate, comprising: providing a substrate having a metal seed layer overlying a major surface; depositing a thin polyvinyl alcohol layer on a substrate; drying the thin polyvinyl alcohol layer at 50°-100° C.; depositing a photosensitive polymer layer on top of the thin polyvinyl alcohol layer; exposing portions of the photosensitive polymer layer to actinic light and then developing the photosensitive polymer layer in an alkaline solution in order to photodelineate a pattern in the photosensitive polymer layer, so as to reveal portions of the underlying thin polyvinyl alcohol layer; rinsing the revealed portions in a heated water or preplate microetch solution to effect removal of the revealed portions, thereby exposing portions of the substrate; baking at 100°-140° C.; electroplating metal into the photodelineated pattern and onto the exposed portions of the substrate to create a circuitry pattern; and removing the remaining portions of the photosensitive polymer layer and the thin polyvinyl alcohol layer by immersing in a heated alkaline solution.
Claim 13
Dependent Claim 26 words
The method of claim 10, wherein a portion of the pattern comprises a cross sectional structure having a height equal to or greater than a width.
Claim 14
Dependent Claim 25 words
The method of claim 10, wherein spacing between adjacent traces in the circuitry pattern is equal to or less than the width of the traces.

References Cited (Backward Citations)

US3961961A Cited
US4193849A Cited
US5576147A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-06-29 2001-12-29 2002-06-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-06-29 2005-12-29 2006-06-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-06-29 2009-12-29 2010-06-30 $7700.00 Window Closed / Lapsed

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