Precision manufacturing of optical disc stampers

This dissertation details the development of a new process called Precision Stamper Manufacturing (PSM) that can be used for compact disc (CD) master-stamper production. In the newly proposed process, stamper substrates are ion machined through a laser-recorded photoresist mask and then used directly for injection molding of CD replicas. This results in reduced manufacturing time, reduced hazardous waste generation, and lower production costs. The new stamper production technique substitutes a ceramic or metal substrate for the conventional glass master disk, and substitutes an automated, repeatable ion machining step for a number of the conventional processing steps, including electroforming, back polishing, and punching. PSM takes less than 20 minutes, compared to 120 minutes for conventional processing. Processes that precede and follow stamper fabrication remain largely unchanged. At the same time PSM eliminates nearly all process steps that produce toxic and hazardous wastes. This process is suitable for production of CD-audio, CD-ROM, and high density DVD formats.; The dissertation outlines the construction and testing of an ion machining system (IMS), and the use of this system to develop CD stamper prototypes. Appropriate substrate materials were evaluated for injection molding and ion machinability, and various photoresist masking materials were evaluated for their recordability and their resistance to erosion and deterioration during ion machining. A number of feasibility experiments were conducted for each PSM processing step, culminating in the production of full-scale CD stamper prototypes which were used to injection mold CD replicas using conventional equipment. The effect of the ion machining process on compact disc (CD) features and the thermal characteristics of the ion machining process were investigated and suitable models were developed.