Wet-recess gap-fill materials for an advanced dual damascene process

摘要

This paper describes the new developer-soluble gap fill materials, which are called wet gap fill materials, with wide process window. In order to reduce isolated/dense fill bias that comes from substrate topography, dry gap fill materials are used in combination with a plasma dry etch-back process. At the same time, the wet gap fill materials are coated thick enough to planarize all the topography and is then recessed using a standard 0.26N tetramethylammonium hydroxide (TMAH) developer. The material recess process takes place in the same track where it is coated and therefore simplifies the process and increases wafer throughput. We developed easy-to-use wet gap fill materials recently. Performances and properties of three types of wet gap fill materials (NCA2546, NCA2549, and NCA2550) based on the same polymer platforms will be discussed.