Trough capacitor plate is formed by preparing a semiconductor wafer, etching a trough for each storage cell, and precipitating a layer containing a dopant on the wafer

摘要

Forming a trough capacitor buried plate in storage cell fields on a semiconductor wafer, comprises preparing the wafer (10), etching a trough (12) for each storage cell (20) in each field on the front of the wafer, and precipitating a layer containing a dopant on the wafer. A resist layer (64) is applied to the front of the wafer, and is exposed to a light source to which it is sensitive. The storage fields are successively exposed, and the resist layer is then developed to form a mask. The structure elements are made deeper, afterwhich the exposed doped layer is removed followed by the remaining resist mask.