Method for forming a multi-anchor DRAM capacitor and capacitor formed

摘要

The present invention discloses a method for forming a DRAM capacitor that has improved charge storage capacity by utilizing a deposition process wherein alternating layers of doped and undoped dielectric materials are first deposited, a deep UV type photoresist layer is then deposited on top of the oxide layers such that during a high density plasma etching process for the cell opening, acidic reaction product is generated by the photoresist layer when exposed to UV emission in an etch chamber such that the sidewall of the cell opening is etched laterally in an uneven manner, i.e., the doped dielectric layer being etched more severely than the undoped dielectric layer thus forming additional surface area and an improved charge storage capacity for the capacitor formed.