Horizontal Electroplating

Since vertical recording is not yet being employed in disk files, the electrochemical deposition of perpendicular materials is still at an exploratory stage. Electroplated vertical media are uncommon. In some cases, the vertical media are modifications of materials used as horizontal media. In others, the vertical medium is produced by introducing a strong shape anisotropy. 

Converting Palladium to Palladium Sulfide. Crimson, invented by Shipley, employs a conversion step after the activator where palladium is changed to palladium sulfide, which is claimed to be more conductive for subsequent electrolytic copper plating. The enhancer stabilizes the conductive film so that it is chemically resistant to imaging steps. The stabilizer neutralizes residues from the enhancer, thereby preventing contamination of subsequent steps. The microetch selectively removes activator from copper surfaces to achieve optimum copper-to-copper bond and reliable dry film adhesion. The process works best in conveyorized horizontal equipment and can be followed by pattern or panel electroplating. (See Fig. 30.3.)... 

Process Variations. ABC, invented in Israel by Holtzman et al., is similar to EE-1. It has been adapted to conveyorized horizontal equipment, but must be followed by a flash electroplating in a proprietary bath. 

Conductron, from LeaRonal, is similar to DPS with the addition of a special cleaner/con-ditioner and a glass-etch step. It has been adapted to conveyorized horizontal equipment and can be followed by pattern or panel electroplating. 

Envision DPS, from Enthone-OMI, and Connect, from M T (now Atotech), are fairly similar to each other, and to DPS, though each has a specific cleaner/conditioner and modified accelerator. No adaptation has been made to horizontal processing. Both processes can be followed by pattern or panel electroplating. 

Compact CP. Compact CP was developed by Atotech in 1987 and is essentially similar to DMS-E, except that it combines the catalyzing and fixation steps, it uses an acid permanganate, and the conductive film is a polypyrrole. The technique is very suitable for use in conveyorized, horizontal equipment. It can be followed by pattern or panel electroplating. 

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