Process simplification in DRAM manufacturing

Abstract

DRAM manufacturers are driving the quest for integration friendly, simplified, and statistically-controlled development. In the DRAM field, strong emphasis must be placed on process simplification as a means of staying cost effective and competitive. In order to examine architecture and integration, both at the module and system levels, it is emphasized that using correct statistical methods in conjunction with advanced technology is important. For simplified development and integration, many aspects of the new assessment are data driven. Also, it is critical to understand the source of variation in the process, obtain stability, and assess the capability relative to specifications of manufacturability and functionality. Statistical control techniques are a requirement for interpreting the results of capability studies, as will be discussed in this paper. In this paper, we have emphasized that both statistical methods and technological innovation are required for optimization. We have investigated several examples that illustrate the methodology followed for the development of statistically controlled, production-worthy processes. The improvement strategy is described both for gate stack and the DRAM cell. The focus of the results described here is both in the context of enhancing capability for existing processes and evaluating alternate options that can be accomplished through the use of advanced technology.