Process window enhancement for deep trench spacer conservation

摘要

In a process for manufacturing deep trench (32) memory cells, a method of enhancing the process window by better protecting the nitride spacer (52) prior to the process of stripping the pad nitride layer (38). The method also provides for the deposition of a nitride liner (64) and offers an additional advantage of not requiring the top shoulder (58) of the nitride spacer (52) to be over etched during its formation.