CONTACT FOR A TRENCH CAPACITOR OF A DRAM CELL ARRANGEMENT

摘要

The invention relates to a DRAM cell arrangement in which each memory cell (1) has a memory capacitor (2) and a read-out transistor (3). A buried strap contact (11) for connecting to the read-out transistor is produced by diffusing dopants out of the electrode of the memory capacitor (2). Said buried strap contact (11) is superposed by the implantations (12) of the source/drain area (5) of the read-out transistor (3), said implantations (12) of the source/drain area (5) forming the boundary of the space charge region of a p/n transition of the memory cell (1). As a result, the generation centres and defects in a buried strap contact are eliminated more than a diffusion length for minority carriers from the space charge region of a p/n transition. Minority carriers of this type then recombine before they reach the p/n transition and are electrically ineffective. This considerably reduces the leakage currents across the p/n transition and increases the retention time.