Semiconductor memory cell and associated fabrication method

US7304342B2 · kind B2 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Thomas Nirschl · Putzbrunn, DE
• Alexander Olbrich · Höhenkirchen-Siegertsbrunn, DE
• Martin Ostermayr · Straubing, DE

Key dates

• Filing date: Jan 18, 2005
• Grant date: Dec 4, 2007
• Expiry date: Dec 29, 2025

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D1/665

Abstract

A semiconductor memory cell and an associated fabrication method are provided in which a storage capacitor is connected to a selection transistor. The storage capacitor is formed in a trench of a semiconductor substrate. At the trench surface, a capacitor dielectric and an electrically conductive filling layer are formed thereon for realization of a capacitor counterelectrode. The filling layer has a projection that extends outside the trench as far as the drain region and is electrically connected thereto.