ABSTRACT
Shrinking technology has remained the most important priority for Dynamic Random Access Memory (DRAM) development. At the same time it is responsible for most of the challenges. The feature of low thermal budget fabrication owing to capacitor formation at early stage is also an advantage; hence, trench cell became more appropriate for merged DRAM where density might not be the first priority. Quadrupling of DRAM density every three years could become practically possible only through technological advancements in the area of lithography, isolation, and etch process. Progress of trench capacitor DRAM structures slowed down on account of difficulty in realizing deeper trench for getting sufficient capacitance in extremely reduced area. Fabrication of transistor in a DRAM chip occupies a central position. Along with the storage capacitor, it is replicated in the core array and affects not only the area but its performance as well. Continued scaling, advancements in DRAM technology, and circuit innovations have made stand-alone DRAM the cheapest memory.
