Semiconductor device and manufacturing method thereof

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

forming a fin structure on a substrate, wherein the fin structure extends in a first direction;

forming a trench passing through the fin structure to form a plurality of active structures, wherein the trench extends, in a second direction and has a bottom recess;

forming a bottom barrier portion formed on the bottom recess of the trench;

forming a lower epitaxy on a lower portion of the trench;

forming a CESL (contact etching stop layer) portion and a ILD (interlayer dielectric) portion within the trench; and

forming an upper epitaxy on an upper portion of the trench, wherein the upper epitaxy is separated from the lower epitaxy;

wherein in forming the CESL portion and the ILD portion within the trench, the manufacturing method further comprises:

forming a CESL material in the trench;

forming a ILD material on the CESL material, wherein the CESL material covers a bottom surface of the ILD material and a lateral surface of the ILD material;

in the same process, removing a portion of the CESL material and a portion of the ILD material, wherein a remaining portion of the CESL material forms the CESL portion and a remaining portion of the ILD material forms the ILD portion.

2 . The manufacturing method as claimed in claim 1 , further comprising:

forming a barrier layer material on a lateral surface of the trench and a sidewall of the bottom recess; and

densifying a portion of the barrier layer material to form a barrier layer;

wherein the barrier layer has a density greater than that of the barrier layer material.

3 . The manufacturing method as claimed in claim 2 , wherein each active structure comprises an upper active region, a lower active region and a middle spacer separating the upper active region from the lower active region; the barrier layer comprises:

the bottom barrier portion located below the middle spacer; and

an upper barrier portion located above the middle spacer.

4 . The manufacturing method as claimed in claim 3 , wherein another portion of the barrier layer material is remained to form a remained barrier portion, and the remained barrier portion is located between the bottom barrier portion and the upper barrier portion.

5 . The manufacturing method as claimed in claim 4 , further comprising:

removing the remained barrier portion to expose the lower active region; and

forming the lower epitaxy on the lower portion of the trench corresponding to the lower active region.

6 . The manufacturing method as claimed in claim 1 , wherein each active structure comprises an upper active region, a lower active region and a middle spacer separating the upper active region from the lower active region; the manufacturing method further comprises:

removing the middle spacer to form a hollow portion; and

forming a middle inner spacer within the hollow portion.

7 . The manufacturing method as claimed in claim 3 , wherein the barrier layer comprises:

a middle barrier portion formed on a lateral surface of the middle spacer;

wherein the middle barrier portion extends from the upper barrier portion toward a lower surface of the middle spacer, but not extends to the lower surface of the middle spacer.

8 . The manufacturing method as claimed in claim 3 , further comprising:

removing the upper barrier portion to expose the upper active region; and

forming the upper epitaxy on the upper portion of the trench corresponding to the upper active region.

9 . The manufacturing method as claimed in claim 3 wherein the barrier layer comprises:

a middle barrier portion formed on a lateral surface of the middle spacer;

wherein the middle barrier portion has a bottom surface aligned with au upper surface of the middle spacer.

10 . A manufacturing method for a semiconductor device, comprising:

forming a fin structure on a substrate, wherein the fin structure extends in a first direction;

forming a trench passing through the fin structure to form a plurality of active structures, wherein the trench extends, in a second direction;

forming a lower epitaxy on a lower portion of the trench;

forming a CESL portion and a ILD portion within the trench; and

forming an upper epitaxy on an upper portion of the trench, wherein the upper epitaxy is separated from the lower epitaxy by the CESL portion and the ILD portion;

wherein in forming the CESL portion and the ILD portion within the trench, the manufacturing method further comprises:

forming a CESL material in the trench;

forming a ILD material on the CESL material, wherein the CESL material covers a bottom surface of the ILD material and a lateral surface of the ILD material;

in the same process, removing a portion of the CESL material and a portion of the ILD material, wherein a remaining portion of the CESL material forms the CESL portion and a remaining portion of the ILD material forms the ILD portion.

11 . The manufacturing method as claimed in claim 10 , further comprises:

before forming the lower epitaxy on the lower portion of the trench, forming a middle barrier portion within the trench.

12 . The manufacturing method as claimed in claim 11 , wherein in forming the middle barrier portion within the trench, the middle barrier portion is formed on a lateral surface of the CESL portion.

13 . The manufacturing method as claimed in claim 10 , further comprising:

before forming the lower epitaxy on the lower portion of the trench, forming a bottom barrier portion in the trench.

14 . The manufacturing method as claimed in claim 13 , wherein in forming the trench passing through the fin structure to form the plurality of active structure, the trench has a bottom recess; the manufacturing method further comprises:

before forming the lower epitaxy on the lower portion of the trench, forming the bottom barrier portion in the bottom recess of the trench.

15 . The manufacturing method as claimed in claim 13 , wherein the bottom barrier portion and the middle barrier portion are formed of the same material.

16 . A manufacturing method for a semiconductor device, comprising:

forming a fin structure on a substrate, wherein the fin structure extends in a first direction;

forming a trench passing through the fin structure to form a plurality of active structures, wherein the trench extends, in a second direction;

forming a lower epitaxy on a lower portion of the trench;

forming a CESL material in the trench;

forming a ILD material in the trench;

in the same process, removing a portion of the CESL material to form a CESL portion and removing a portion of the ILD material to form an ILD portion;

forming an upper epitaxy on an upper portion of the trench, wherein the upper epitaxy is separated from the lower epitaxy by the CESL portion and the ILD portion.

17 . The manufacturing method as claimed in claim 16 , further comprising:

before forming the CESL material in the trench, forming an upper barrier portion in the trench.

18 . The manufacturing method as claimed in claim 16 , further comprising:

forming a middle barrier portion; and

forming a middle inner spacer in the active structure, wherein the middle inner spacer has a lower surface;

wherein the middle barrier portion extends toward the lower surface of the middle inner spacer, but not to the lower surface of the middle inner spacer.

19 . The manufacturing method as claimed in claim 16 , further comprising:

before forming the lower epitaxy on the lower portion of the trench, forming a bottom barrier portion in the trench.

20 . The manufacturing method as claimed in claim 19 , wherein the bottom barrier portion and a middle barrier portion are formed of the same material.