METHOD OF FORMING SEMICONDUCTOR DEVICES HAVING WAFER BACK-SIDE CAPACITORS

• Main Authors: HSU LOUIS LUN, VIDYA RAMACHANDRAN, WONG KEITH KWONG HON, LAWRENCE CLEVENGER, RADENS CARL JOHN, TIMOTHY JOSEPH DALTON, YANG CHIHAO
• Format: Patent
• Language: English
• Published: 02.05.2013
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PROBLEM TO BE SOLVED: To provide a method of forming semiconductor devices having wafer back-side capacitors.SOLUTION: A method includes the following steps of: preparing an SOI substrate having a buried insulating layer inserted between a front-side active silicon layer and a back-side bulk silicon layer; forming on the front side of the SOI substrate an integrated circuit including a buried contact plug extending from the front side of the SOI substrate while penetrating through the buried insulating layer; performing back-side etching process to form a trench in the bulk silicon layer and expose an end part of the buried contact plug to the back side surface of the buried insulating layer; and forming in a trench a capacitor including a first capacitor plate, a second capacitor plate, and a capacitor dielectric layer inserted between the first and second capacitor plates. The first capacitor plate is formed to contact with the exposed end part of the buried contact plug.