DRAM with dopant stop layer and method of fabricating the same
View Patent ↗A DRAM with dopant stop layer includes a substrate, a trench-type transistor and a capacitor electrically connected to the trench-type transistor. The trench-type transistor includes a gate structure embedded in the substrate. A source doping region and a drain doping region are disposed in the substrate at two sides of the gate structure. A boron doping region is disposed under the source doping region. A dopant stop layer is disposed within the boron doping region or below the boron doping region. The dopant stop layer includes a dopant selected from the group consisting of C, Si, Ge, Sn, Cl, F and Br.
1. A DRAM with a dopant stop layer, comprising:
a substrate; and
a trench-type transistor disposed on said substrate, said trench-type transistor comprising:
a gate structure embedded in said substrate;
a source doping region disposed in said substrate and at a first side of said gate structure;
a drain doping region disposed in said substrate and at a second side of said gate structure;
a boron doping region disposed in said substrate and under said source doping region;
a capacitor electrically connected to said drain doping region; and
a dopant stop layer disposed in said substrate and under said boron doping region, wherein said dopant stop layer comprises a dopant selected from the group consisting of C, Si, Ge, Sn, Cl, F and Br.
2. The DRAM with a dopant stop layer of claim 1 , wherein said dopant stop layer is in contact with said boron doping region.