Patent ID: 6812487
Filing Date: 2004-11-02
Classification: G11C,H01L

Abstract:
A test key for validating the doping concentration of buried layers within a deep trench capacitor, which is deposited in the scribe line region of a wafer, the test key comprising:a trench capacitor deposited in the scribe line region with an electrode layer of a first doping concentration, a first conducting layer of a second doping concentration and a second conducting layer of a third doping concentration; an isolation region deposited in the trench capacitor, penetrating the second conducting layer, and extending into the first conducting layer so that the second conducting layer is divided into a first and second portion; a first plug coupled to a first side of the first portion of the second conducting layer; a second plug coupled to a second side of the first portion of the second conducting layer; and a third plug coupled to the second portion of the second conducting layer.