High capacity capacitor and corresponding manufacturing process

US6222245A · kind A · utility

Assignee

• SGS-Thomson Microelectronics S.A. · IT

Inventors

• Roberto Bez · Milano, IT
• Emilio Camerlenghi · Bergamo, IT

Key dates

• Filing date: Oct 30, 1996
• Grant date: Apr 24, 2001
• Expiry date: Oct 30, 2016

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D1/66

Abstract

The invention relates to a high-capacitance capacitor which is monolithically integratable on a semiconductor substrate doped with a first type of dopant and accommodating a diffusion well which is doped with a second type of dopant and has a first active region formed therein. A layer of gate oxide is deposited over the diffusion well which is covered with a first layer of polycrystalline silicon and separated from a second layer of polycrystalline silicon by an interpoly dielectric layer. Advantageously, the high-capacitance capacitor of the invention includes a first elementary capacitor having the first and second layers of polycrystalline silicon as its conductive plates, and the interpoly dielectric layer as the isolation dielectric, and a second elementary capacitor having the first layer of polycrystalline silicon and the diffusion well as its conductive plates and the gate oxide layer as the isolation dielectric.