Production of a trench capacitor comprises filling a trench with a filler, forming an insulating collar, removing the filler, forming a trenched plate using low pressure gas phase doping, etc.

摘要

Production of a trench capacitor comprises forming a trench (108) in a substrate (101); filling a lower region of the trench with a first filler (152); forming an insulating collar in an upper region of the trench; removing the first filler; forming a trenched plate (165) in the substrate in the surrounding of the lower region of the trench as first capacitor plate using low pressure gas phase doping; forming a dielectric layer to line the lower region of the trench and the inner side of the collar as capacitor dielectric and filling the trench with a conducting second filler as second capacitor plate. Preferred Features: Formation of the trenched plate uses AsH3 or PH3 as doping gas and H2 or He as carrier gas.