36results about How to "Improve refresh feature" patented technology

Double refresh executing means is changed in accordance with a manner (distributed refresh or burst refresh) of a refresh command so as to suppress a drop of internal power supply that occurs upon double refresh.

A recess gate-type semiconductor device includes a gate electrode having a recessed portion at least partially covering a recess trench in an active region, and source / drain regions disposed in the active region that are separated by the gate electrode. The recess trench is separated from sidewalls of a device isolation region in a first direction and contacts sidewalls of the device isolation region in a second direction. The width of the recess trench of the active region in the second direction may be greater than the width of the source / drain regions in the second direction, and the recessed portion of the gate electrode may have tabs protruding in the first direction at its corners. Therefore, the semiconductor device has excellent junction leakage current and excellent refresh characteristics.

A method for fabricating a semiconductor device includes: forming a gate trench in a semiconductor substrate; forming a gate dielectric layer over a bottom surface and sidewalls of the gate trench; forming a first work function layer over the gate dielectric layer; doping a work function adjustment element to form a second work function layer which overlaps with the sidewalls of the gate trench; forming a gate conductive layer that partially fills the gate trench; and forming doped regions inside the semiconductor substrate on both sides of the gate trench.

A method for forming a semiconductor device having recess channel includes forming a hard mask film pattern for exposing first regions for forming the trenches on a semiconductor substrate; forming first trenches by a first etching process using the hard mask film pattern as a mask, and removing the hard mask film pattern; forming a barrier film on the semiconductor substrate including the first trenches; forming an ion implantation mask film for exposing the first trenches on the barrier film; forming an ion implantation region in the semiconductor substrate below the first trenches using the ion implantation mask film and the barrier film; forming bulb-shaped second trenches by a second etching process using the ion implantation mask film and the barrier film as a mask, so that bulb-type trenches for recess channels, each including the first trench and the second trench, are formed; and removing the ion implantation mask film and the barrier film.

Each cell unit has a cell plate electrically isolated from the cell plates in the other cell units.

A semiconductor memory device and a self-refresh method in which the semiconductor memory device includes a plurality of input / output ports having respective independent operation, a period of self-refresh through one of the plurality of input / output ports being subordinate to a kind of operation through another input / output port. Whereby, a refresh characteristic in a multi-port semiconductor memory device including a dual-port semiconductor memory device may be improved.