Infineon Technologies Ag

Frank Lau

Josef Willer

Luis-Felipe Giles

Rainer Liebmann

Dezs&ouml; Takacs

In a method for fabricating a field effect transistor, a first source/drain region and a second source/drain region are formed in a substrate. A channel region is formed between the first source/drain region and the second source/drain region. A gate region is formed on the channel region. Micro-cavities are formed in the substrate at least below the channel region, and the micro-cavities are oxidized.

Field effect transistor

Method for fabricating a field effect transistor, and field effect transistor

A memory cell includes a channel region between source/drain regions at the top side of a semiconductor body and is provided, transversely with respect to the longitudinal direction, with a bulge formed in the semiconductor material. This results in a uniform distribution of the strength of a radially directed electric field and avoids field strength spikes at lateral edges of the channel region. A storage layer sequence is situated between the channel region and the gate electrode as part of a word line.

Charge trapping memory cell

The present invention relates to a flash memory cell comprising a silicon substrate having an active region comprising a channel region and source-/drain-regions, the active region comprising a projecting portion, which projecting portion at least comprising said channel region; a tunneling dielectric layer formed on the surface of said active region; a floating gate formed on the surface of said tunneling dielectric layer for storing electric charges; an inter-gates coupling dielectric layer formed on the surface of said floating gate, and a control gate formed on the surface of said inter-gates coupling dielectric layer, wherein said floating gate is formed to have a groove-like shape for at least partly encompassing said projecting portion of said active region. This invention further relates to a flash memory device comprising such flash memory cells, as well as a manufacturing method thereof.

Flash memory cell, flash memory device and manufacturing method thereof

A memory cell includes a storage transistor having the following structure and being dimensioned to shorten program and erase times. A semiconductor body includes a top surface and a trench formed therein having walls joined by a curved bottom. A source zone in the semiconductor body is doped from the top surface. A drain zone in the semiconductor body is doped from the top surface. Junctions of the source and drain zones are beneath each. A gate electrode on the top surface of the semiconductor body is disposed between the source zone and the drain zone in the trench. A dielectric layer isolates the gate electrode from the semiconductor body and acts as a storage medium. Each of the junctions intersects a respective one of the walls at a respective depth from the bottom. A respective spacing across the trench is defined at each depth.

Growing community of inventors

Bad Aibling, Germany

Frank Lau