Method of manufacturing a field effect transistor device with recessed channel and corner gate device

US7371645B2 · kind B2 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Klaus Muemmler · Dresden, DE
• Peter Baars · Dresden, DE
• Stefan Tegen · Dresden, DE

Key dates

• Filing date: Dec 30, 2005
• Grant date: May 13, 2008
• Expiry date: May 11, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/513

Abstract

Fabrication of recessed channel array transistors (RCAT) with a corner gate device includes forming pockets between a semiconductor fin that includes a gate groove and neighboring shallow trench isolations that extend along longs sides of the semiconductor fin. A protection liner covers the semiconductor fin and the trench isolations in a bottom portion of the gate groove and the pockets. An insulator collar is formed in the exposed upper sections of the gate groove and the pockets, wherein a lower edge of the insulator collar corresponds to a lower edge of source/drain regions formed within the semiconductor fin. The protection liner is removed. The bottom portion of the gate groove and the pockets are covered with a gate dielectric and a buried gate conductor layer. The protection liner avoids residuals of polycrystalline silicon between the active area in the semiconductor fin and the insulator collar.