Semiconductor device having vertical-type channel

1. A semiconductor device, comprising:

an active region including a surface region and first recesses formed on both sides of the surface region, the active region extending along a first direction;

a device isolation structure surrounding the active region;

a pair of gate lines extending along the surface region of the active region in a second direction perpendicular to the first direction;

a plurality of second recesses formed in the device isolation structure beneath the gate lines and including given portions of the gate lines filled into the second recesses;

a plurality of first junction regions formed in the active region beneath the first recesses; and

a second junction region formed in the surface region between the gate lines,

wherein the second junction region defines at least two vertical-type channels below the gate line with the plurality of first junction regions,

wherein the first recesses are disposed on both sides of the surface region along the first direction, and the plurality of second recesses are disposed beneath the gate lines along the second direction which is perpendicular to the first direction.

2. The semiconductor device of claim 1 , wherein the second recesses are formed in both sides of the active region below the gate lines.

3. The semiconductor device of claim 2 , wherein each sidewall of the active region is a sidewall of each of the second recesses.

4. The semiconductor device of claim 1 , wherein each of the first junction regions contacts a storage node, and the second junction region contacts a bit line.

5. The semiconductor device of claim 4 , wherein the first junction regions and the second junction region are doped with N-type impurities.

6. A semiconductor device, comprising:

an active region including a surface region and first recesses formed on both sides of the surface region, the active region extending along a first direction;

a device isolation structure surrounding the active region;

a pair of gate lines extending along the surface region of the active region in a second direction perpendicular to the first direction;

a plurality of second recesses formed in the device isolation structure beneath the gate lines and including given portions of the gate lines filled into the second recesses;

a plurality of first junction regions formed in the active region beneath the first recesses; and

a second junction region formed in the surface region between the gate lines,

wherein the second junction region defines at least two vertical-type channels below the gate line with the plurality of first junction regions;

wherein a depth of each of the first recesses is less than that of each of the second recesses and the depth of each of the second recesses is less than that of the device isolation layer.

7. A semiconductor device, comprising:

an active region including a surface region and first recesses formed on both sides of the surface region, the active region extending along a first direction;

a device isolation structure surrounding the active region;

a pair of gate lines extending along the surface region of the active region in a second direction perpendicular to the first direction;

a plurality of second recesses formed in the device isolation structure beneath the gate lines and including given portions of the gate lines filled into the second recesses;

a plurality of first junction regions formed in the active region beneath the first recesses; and

a second junction region formed in the surface region between the gate lines,

wherein the second junction region defines at least two vertical-type channels below the gate line with the plurality of first junction regions,

wherein each of the first recesses and the plurality of second recesses is formed as a distinct trench structure.