Method for the production of radiant energy imaged printed circuit boards
AssigneePhotocircuits Division of Kollmorgen Corporation
InventorsJoseph Polichette, Edward J. Leech
Life of this patent
Estimating the term…
Abstract
Radiant energy imaged printed circuit boards are provided by treating an insulating base with a composition of a reducible metal salt and a radiant energy sensitive compound, exposing the treated base to radiant energy in selected areas to produce metallic nuclei in the form of a non-conducting real image of the desired circuit pattern, rinsing the exposed base to remove unexposed metal salts and exposing the real image to an electroless metal bath to build up conductor lines of electroless metal thereon. In an alternative procedure, conductor lines are built up by electroplating with the same or a different metal and, optionally, solder coating.
Claims53
A process for making printed circuit boards comprising treating an insulating base with a solution of a reducible non-noble metal salt, a radiation sensitive reducing compound and a secondary reducer, exposing the treated base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern, rinsing the exposed base to remove unexposed metal salts, and exposing the real image to an electroless metal bath to build up conductor lines of electroless metal thereon.
A process for making printed circuit boards comprising treating an insulating base with a solution of a reducible non-noble metal salt, a radiation sensitive reducing compound and a secondary reducer, exposing the treated base to radiant energy in selected areas to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern, rinsing the exposed base to remove unexposed metal salts, exposing the real image to an electroless metal bath to build up conductor lines of electroless metal thereon said process including the subsequent step of solder coating the circuit pattern.
A process for making printed circuit boards comprising treating an insulating base with a solution of a reducible non-noble metal salt, a radiation sensitive reducing compound and a secondary reducer, exposing the treated base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern, rinsing the exposed base to remove unexposed metal salts, exposing the real image to an electroless metal bath to build up conductor lines of electroless metal thereon said process including the step of providing the insulating base in areas on which electroless metal deposition is not desired with a poison capable of lowering the catalytic activity in the vicinity of surface imperfections which are present in said areas.
A process for making printed circuit boards comprising treating an insulating base with a solution of a reducible non-noble metal salt, a radiation sensitive reducing compound and a secondary reducer, exposing the treated base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern, rinsing the exposed base to remove unexposed metal salts, exposing the real image to an electroless metal bath to build up conductor lines of electroless metal thereon, said process including the subsequent step of depositing electroplated metal on the electroless metal.
In a process for making printed circuit boards, the steps comprising:
- a. treating a base material having a non-polar surface with a pre-activating compound or composition;
- b. treating the pre-activated base material with an oxidizing agent;
- c. treating the pre-activated, oxidized base material with a reducing agent;
- d. treating the base to remove the pre-activating agent and excess oxidizing and reducing agents;
- e. treating the base with a poison to retard extraneous electroless metal deposition;
- f. drying the base;
- g. treating the base with a solution of a reducible non-noble metal salt, a radiation sensitive reducing compound and a secondary reducer;
- h. drying the base;
- i. exposing the base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern;
- j. rinsing the base to remove unexposed metal salts;
- k. immersing the base in an initial electroless metal bath to intensify the real image;
- l. electrolessly plating the intensified image to form conductor lines of the desired thickness on the base;
- m. rinsing the base;
- and
- n. post-curing the base to produce the printed circuit board.
In a process for making printed circuit boards, the steps comprising:
- a. providing an insulating base with a resinous oxidizable surface;
- b. treating the base with an oxidizing agent to oxidize the surface and produce a microporous surface;
- c. treating the base having a microporous surface to remove excess oxidizing agent;
- d. treating the base with a poison to retard extraneous electroless metal deposition;
- e. drying the base;
- f. treating the base with a solution of a reducible non-noble metal salt, a radiation sensitive reducing compound and a secondary reducer;
- g. drying the base;
- h. exposing the base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern;
- i. rinsing the base to remove unexposed metal salts;
- j. immersing the base in an initial electroless metal bath to intensify the real image;
- k. electrolessly plating the intensified image to form conductor lines of the desired thickness on the base;
- and
- l. rinsing the base to produce the printed circuit board.
In a process for making printed circuit boards, the steps comprising:
- a. providing an insulating base material having a resinous oxidizable surface;
- b. treating the base with an oxidizing agent to oxidize the surface and produce a microporous surface;
- c. treating the base having a microporous surface to remove excess oxidizing agent;
- d. treating the base with a poison to retard extraneous electroless metal deposition;
- e. drying the base;
- f. treating the base with a solution of a reducible non-noble metal salt, a radiation sensitive reducing compound and a secondary reducer;
- g. drying the base;
- h. exposing the base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern;
- i. rinsing the base to remove unexposed metal salts;
- j. immersing the base in an initial electroless metal bath to intensify the real image;
- and
- k. electroplating the intensified image to form conductor lines of the desired thickness on the base to produce the printed circuit board.
In a process for making printed circuit boards, the steps comprising:
- a. treating an insulating base material having a non-polar surface with a pre-activating compound or composition;
- b. treating the pre-activated base material with an oxidizing agent to produce a microporous wettable surface on said base;
- c. treating the pre-activated, oxidized base material with a reducing agent to neutralize and remove excess oxidizing agent from said base;
- d. treating the base to remove the pre-activating agent and excess oxidizing and reducing agents;
- e. treating the base with a poison to retard extraneous electroless metal deposition;
- f. drying the base;
- g. treating the base with a solution of a reducible metal metal salt, a radiation sensitive reducing compound and a secondary reducer;
- h. drying the base;
- i. exposing the base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern;
- j. rinsing the base to remove unexposed metal salts;
- k. immersing the base in an initial electroless metal bath to intensify the real image;
- and
- l. electroplating the intensified image to form conductor lines of the desired thickness on the base to produce the printed circuit board.
In a process for making printed circuit boards, the steps comprising:
- a. treating an insulating base material having a non-polar surface with a pre-activating compound or composition;
- b. treating the pre-activated base material with an oxidizing agent to produce a microporous, wettable surface on said base;
- c. treating the pre-activated, oxidized base material with a reducing agent to neutralize and remove excess oxidizing agent from said base;
- d. treating the base to remove the pre-activating agent and excess oxidizing and reducing agents;
- e. treating the base with a poison to retard extraneous electroless metal deposition;
- f. drying the base;
- g. treating the base with a solution of a reducible copper salt and a radiation sensitive anthraquinone compound;
- h. drying the base;
- i. exposing the base to light through a negative mask to produce a real image comprised of free copper nuclei in the form of the desired circuit pattern;
- j. rinsing the base to remove unexposed copper salts;
- k. immersing the base in an initial electroless copper bath to intensify the real image;
- l. immersing the base in an electroless copper bath and plating the intensified image to form conductor lines of the desired thickness;
- m. rinsing the base;
- and
- n. post-curing the base to produce the printed circuit board.
A process for making printed circuit boards comprising treating an insulating base with a composition of a reducible metal salt selected from the group consisting of copper salts, nickel salts, cobalt salts, iron salts and mixtures thereof, a radiation sensitive reducing compound and a secondary reducer, exposing the treated base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern, rinsing the exposed base to remove unexposed metal salts, and exposing the real image to an electroless metal bath to build up conductor lines of electroless metal thereon.
In a process for making printed circuit boards, the steps comprising:
- a. treating a base material having a non-polar surface with a pre-activating compound or composition;
- b. treating the pre-activated base material with an oxidizing agent;
- c. treating the pre-activated, oxidized base material with a reducing agent;
- d. treating the base to remove the pre-activating agent and excess oxidizing and reducing agents;
- e. drying the base;
- f. treating the base with a solution of a reducible metal salt selected from copper salts, nickel salts, cobalt salts, iron salts and mixtures thereof, a radiation sensitive reducing compound and a secondary reducer;
- g, drying the base;
- h. exposing the base to radiant energy in selected areas to produce free metallic nuclei in the form of a non-conducting real image of the desired circuit pattern;
- i. rinsing the base to remove unexposed metal salts;
- j. immersing the base in an initial electroless metal bath to intensify the real image;
- k. electrolessly plating the intensified image to form conductor lines of the desired thickness on the base;
- l. rinsing the base;
- and
- m. post curing the base to produce the printed circuit board.
Dependencies are inferred from the claim text.