Sematech, Albany, N.Y., reports that promising progress has been made in qualifying outgassing specifications for extreme ultraviolet (EUV) lithography. In a joint collaboration with the JSR Corp., Japan, Sematech has experimentally proven an improved evaluation method that reduces the amount of testing of commercial EUV resists from every formulation to just three samples per family.
This achievement has the potential to enable substantial cost savings by significantly improving the resist learning cycle. Results confirm that the concentration of the major components in a resist can be varied without the need for requalification, which can result in a potential savings of few hundred outgas tests for each resist family.
The reduction of EUV resist outgassing to minimize or prevent possible contamination of EUV exposure tools is critical to the development of EUV resists. Therefore, it is vital that resist chemistries meet stringent outgassing specifications before being used in an EUV scanner. Today, however, the resist learning cycle is excessively long and inefficient due in part to the lengthy outgas tests that resist material formulations must undergo before being subjected to exposure in a production EUV scanner.
Over the past decade, SEMATECH has reduced resist and materials development cycle time by providing the industry access to successive generations of small field exposure tools. SEMATECH’s projects have succeeded in measuring the outgassing characteristics in hundreds of EUV resists and materials formulations, and delivering thousands of EUV exposure shifts to member companies to evaluate tens of thousands of materials formulations.
