Method of forming semiconductor device including semiconductor liner
A method for forming a semiconductor device may include forming, on a substrate, a trench which delimits a preliminary active region. A buffer layer may be formed on the preliminary active region using a first heat treatment process that is performed at 520° C. to 580° C. A sacrificial layer may be formed by replacing the buffer layer. An active region may be exposed by removing the sacrificial layer. A semiconductor liner may be formed on the active region.
1 . A method for forming a semiconductor device, comprising:
forming, on a substrate, a trench which delimits a preliminary active region;
forming a buffer layer on the preliminary active region using a first heat treatment process that is performed at 520° C. to 580° C.;
forming a sacrificial layer on the preliminary active region by replacing the buffer layer;
exposing an active region by removing the sacrificial layer; and
forming a semiconductor liner on the active region.
2 . The method according to claim 1 , wherein the first heat treatment process includes supplying a gas or radicals containing N and O onto the preliminary active region.
3 . The method according to claim 1 , wherein the first heat treatment process includes supplying nitrogen gas and oxygen gas onto the preliminary active region, and the oxygen gas is supplied at a flow rate ranging from 0.1 SLM (standard liter per minute) to 1 SLM.
4 . The method according to claim 1 , wherein a thickness of the buffer layer ranges from 0.1 nm to 1 nm.
5 . The method according to claim 1 , wherein the buffer layer includes at least one or more of silicon oxide, silicon nitride or silicon oxynitride.
6 . The method according to claim 1 , wherein the forming of the sacrificial layer by replacing the buffer layer comprises:
supplying a reactive gas such as a nitrogen-containing gas, a fluorine-containing gas, a hydrogen-containing gas or a combination thereof onto the substrate with the buffer layer.
7 . The method according to claim 1 , wherein the forming of the sacrificial layer by replacing the buffer layer comprises:
supplying nitrogen trifluoride (NF 3 ) gas, ammonia (NH 3 ) gas, hydrogen (H 2 ) gas and argon (Ar) gas onto the substrate with the buffer layer.
8 . The method according to claim 1 , wherein the sacrificial layer includes ammonium fluorosilicate ((NH 4 ) 2 [SiF 6 ]).
9 . The method according to claim 1 , wherein the exposing of the active region by removing the sacrificial layer includes a second heat treatment process that is performed at a temperature of 80° C. to 150° C.
10 . The method according to claim 9 , wherein the second heat treatment process is performed in a chamber to which nitrogen (N 2 ) gas is supplied.
11 . The method according to claim 1 , wherein the preliminary active region has a first width, the active region has a second width, and the second width is smaller than the first width by 0.5 nm to 1.1 nm.
12 . The method according to claim 1 , wherein the forming of the semiconductor liner on the active region includes a selective epitaxial growth (SEG) process or a selective poly growth (SPG) process.
13 . The method according to claim 1 , wherein the semiconductor liner includes monocrystalline silicon, polysilicon or a combination thereof.
14 . The method according to claim 1 , wherein a thickness of the semiconductor liner ranges from 1 nm to 4 nm.
15 . A method for forming a semiconductor device, comprising:
forming, on a substrate, an isolation layer which delimits an active pattern;
forming a word line which traverses the active pattern;
forming a plurality of source/drain regions in the active pattern adjacent to the word line;
forming a bit line which is connected to one of the plurality of source/drain regions;
forming a bottom electrode which is connected to another one of the plurality of source/drain regions;
forming a capacitor dielectric layer on the bottom electrode; and
forming a top electrode on the capacitor dielectric layer,
wherein the forming of the isolation layer comprises:
forming, on the substrate, a trench which delimits a preliminary active region;
forming a buffer layer on the preliminary active region using a first heat treatment process that is performed at 520° C. to 580° C.;
forming a sacrificial layer by replacing the buffer layer;
exposing an active region by removing the sacrificial layer;
forming a semiconductor liner on the active region, the active region and the semiconductor liner configuring the active pattern; and
forming the isolation layer in the trench.
16 . A method for forming a semiconductor liner for accommodating a semiconductor device, comprising:
forming, on a substrate, a trench which delimits a preliminary active region;
forming a buffer layer on the preliminary active region using a first heat treatment process which consumes material of the preliminary active region, and thereby forms for the semiconductor liner a device region having a first width smaller than a second width of the preliminary active region prior to the first treatment;
forming a sacrificial layer by replacing the buffer layer;
removing the sacrificial layer and thereby exposing the device region; and
forming the semiconductor device on the device region.
17 . The method of claim 16 , wherein the first width of the device region is smaller than the second width of the preliminary active region by 0.5 nm to 1.1 nm.
18 . The method of claim 16 , wherein
the device region comprises a strip of a semiconductor wafer, and
after removing the sacrificial layer, the first width of the device region is substantial enough so that the device region does not lean.
19 . The method of claim 18 , wherein the first width of the device region ranges from 10 to 30 nm.