Aspects in the progression of materials and processes for 256Mb-DRAM and beyond

Abstract

It's has been the general opinion of device manufacturers that deep ultraviolet imaging will be the imaging method required to produce 250nm and sub-250nm geometries for 256Mb-DRAM's and related logic technology. Traditional Wine lithography may not capable of manufacturing at these geometries and the use of deep UV radiation with «chemically amplified» photoresists will be required for these device programs. Issues regarding the problems that researchers are combating or have not yet considered in the evolutionary chain of deep ultraviolet photoresist development and implementation will be discussed. As researchers continue developing environmentally stable materials, there is a series of issues that device manufacturers need to resolve today as new quarter micron fabs are currently under construction. Fab designers may need to consider additional space for specialty tools or processes in order to produce quarter micron lithography. The issues concerning materials, process, reflectivity control, manufacturing facilities, quality control, photoresist manufacturing, photoresist cost and a proposed roadmap for the next several years of development will be discussed. The author will also provide a brief overview of current Mine photoresists and their capability to the 300= geometry region along with some basic chemistry regarding the principles of DNQ's and chemically amplified photoresists.