Methods for manufacturing a semiconductor device

1. A method for manufacturing a semiconductor device, the method comprising:

forming a first source/drain region within a first well region;

forming a second source/drain region within a second well region;

forming an active region electrically coupled between the first source/drain region and the second source/drain region, wherein the active region comprises a region of lower doping concentration disposed between the first well region and the second well region, wherein the region of lower doping concentration has a doping concentration lower than a doping concentration of each of the first well region and the second well region;

forming a trench disposed between the second source/drain region and at least a portion of the active region;

forming a first isolation layer on a bottom and sidewalls of the trench;

forming electrically conductive material in the trench, wherein the electrically conductive material is disposed over the first isolation layer;

forming a second isolation layer above the active region; and

forming a gate region above the second isolation layer;

wherein the electrically conductive material is coupled to the gate region, and

wherein the first well region is spaced apart from the second well region by the active region.

2. The method of claim 1 , wherein the first source/drain region is doped with first doping atoms of a first conductivity type; and

wherein the first well region is doped with second doping atoms of a second conductivity type, wherein the second conductivity type is different from the first conductivity type.

3. The method of claim 1 , wherein the second source/drain region is doped with doping atoms of a first conductivity type; and

wherein the second well region is doped with the doping atoms of the first conductivity type.

4. The method of claim 1 ,

wherein the trench is formed as a shallow trench isolation structure.

5. The method of claim 1 , further comprising:

forming a lightly doped drain region disposed between the first source/drain region and the active region.

6. The method of claim 1 , wherein the first isolation layer comprises a material selected from the group consisting of silicon oxide, silicon nitride and high-k material.

7. The method of claim 1 , wherein the second isolation layer comprises a material selected from the group consisting of silicon oxide, silicon nitride and high-k material.

8. The method of claim 1 ,

wherein at least one of the first source/drain region and the second source/drain region comprises silicide.

9. The method of claim 1 ,

wherein the gate region is electrically coupled with the electrically conductive material.

10. The method of claim 1 ,

wherein the electrically conductive material comprises a metal.

11. The method of claim 1 , wherein the metal is a material selected from the group consisting of tungsten, aluminum, copper and a silicide.

12. The method of claim 1 , further comprising:

forming a further trench disposed next to the first source/drain region opposite to the active region.

13. The method of claim 12 ,

wherein the further trench is configured as a shallow trench isolation structure.

14. The method of claim 1 , wherein forming the trench comprises forming the trench in a substrate, and

wherein forming the first isolation layer on the bottom and the sidewalls of the trench further comprising:

forming a liner layer over an entire exposed upper surface of the substrate, the bottom surface and the sidewall surfaces of the trench; and

removing first portions of the liner layer from the entire exposed upper surface of the substrate, wherein second portions of the liner layer covering the bottom surface and the sidewall surfaces of the trench remain.

15. The method of claim 14 , wherein removing the first portions of the liner layer from the entire exposed upper surface of the substrate comprises a polishing process.

16. The method of claim 15 ,

wherein the polishing process comprises a chemical mechanical polishing (CMP) process.

17. The method of claim 14 , wherein forming the gate region and forming the electrically conductive material in the trench further comprising:

depositing a layer of the electrically conductive material over the entire exposed upper surface of the substrate, wherein the trench is completely filled with the layer of the electrically conductive material; and

patterning the layer of the electrically conductive material to form the gate region and the electrically conductive material filling the trench.

18. A method for manufacturing a semiconductor device, the method comprising:

forming a first well region in the substrate;

forming a second well region in the substrate and spaced apart from the first well region;

forming a first source/drain region within a first well region;

forming a second source/drain region in the second well region;

forming a drain extended structure including a trench in the second well region and next to the second source/drain region;

forming an active region electrically coupled between the first source/drain region and the second source/drain region, wherein the active region comprises a region of lower doping concentration than a doping concentration of each of the first well region and the second well region, and wherein the active region is disposed between the first well region and the second well region;

forming a first isolation layer on a bottom and sidewalls of the trench;

forming electrically conductive material in the trench, wherein the electrically conductive material is disposed over the first isolation layer;

forming a second isolation layer over the active region; and

forming a gate structure over the second isolation layer;

wherein the electrically conductive material is coupled to the gate structure.