Method for fabricating a semiconductor device
The semiconductor device includes a substrate, a stack structure including gate patterns and interlayer insulating films that are alternately stacked on the substrate, an insulating pillar extending in a thickness direction of the substrate within the stack structure, a polycrystalline metal oxide film extending along a sidewall of the insulating pillar between the insulating pillar and the stack structure, a liner film having a transition metal between the insulating pillar and the polycrystalline metal oxide film, and a tunnel insulating film, a charge storage film, and a blocking insulating film which are disposed in order between the polycrystalline metal oxide film and the gate patterns.
1. A method for fabricating a semiconductor device, the method comprising:
sequentially forming a liner film and a metal oxide film on a substrate, the liner film including a transition metal and being in contact with the metal oxide film;
crystallizing the metal oxide film through an annealing process;
forming a liner pattern and a metal oxide pattern on the substrate by patterning the liner film and the metal oxide film;
forming an insulating film extending along a sidewall of the liner pattern, a sidewall of the metal oxide pattern, and an upper surface of the metal oxide pattern; and
forming a gate electrode on the insulating film,
wherein the annealing process is performed in a nitrogen atmosphere or an oxygen atmosphere.
2. The method as claimed in claim 1 , wherein crystallizing the metal oxide film is performed before patterning the liner film and the metal oxide film.
3. The method as claimed in claim 1 , wherein crystallizing the metal oxide pattern is performed before forming the insulating film.
4. The method as claimed in claim 1 , wherein the metal oxide film includes an In—Ga oxide film, an In—Zn oxide film, or an In—Ga—Zn oxide film.
5. The method as claimed in claim 1 , wherein the transition metal includes at least one of Ta, Ti, or Mo.
6. The method as claimed in claim 1 , further comprising forming a contact on at least one side of the gate electrode,
wherein the contact penetrates through the insulating film to be connected to the metal oxide pattern.
7. The method as claimed in claim 1 , further comprising forming an insulating buffer film between the substrate and the liner film.
8. A method for fabricating a semiconductor device, the method comprising:
forming an insulating buffer film;
sequentially forming a liner film and a metal oxide film on the insulating buffer film;
crystallizing the metal oxide film through an annealing process;
forming a liner pattern and a crystallized metal oxide pattern on the insulating buffer film by patterning the crystallized metal oxide film and the liner film;
forming an insulating film extending along a sidewall of the liner pattern, a sidewall of the crystallized metal oxide pattern, and an upper surface of the crystallized metal oxide pattern; and
forming a gate electrode on the insulating film,
wherein the liner pattern includes a transition metal oxide or a transition metal oxynitride.
9. The method as claimed in claim 8 , wherein the annealing process is performed in a nitrogen atmosphere or an oxygen atmosphere.
10. The method as claimed in claim 8 , wherein the liner film includes at least one of a Ta film, a Ti film, a Mo film, a TaN film enriched with Ta, a TiN film enriched with Ti, or a MoN film enriched with Mo.
11. The method as claimed in claim 8 , wherein the crystallized metal oxide pattern includes an In—Ga oxide film, an In—Zn oxide film, or an In—Ga—Zn oxide film.
12. The method as claimed in claim 8 , further comprising forming a contact on at least one side of the gate electrode,
wherein the contact penetrates through the insulating film to be connected to the crystallized metal oxide pattern.
13. A method for fabricating a semiconductor device, the method comprising:
sequentially forming a transition metal film and a metal oxide film on a substrate, the transition metal film being in contact with the metal oxide film;
forming a transition metal pattern and a metal oxide pattern on the substrate by patterning the transition metal film and the metal oxide film;
crystallizing the metal oxide pattern through performing an annealing process in an oxygen atmosphere;
forming a gate insulating film extending along a sidewall of the transition metal pattern, a sidewall of the crystallized metal oxide pattern, and an upper surface of the crystallized metal oxide pattern;
forming a gate electrode on the gate insulating film; and
forming a contact on both sides of the gate electrode, wherein the contact penetrates through the gate insulating film to be connected to the crystallized metal oxide pattern.
14. The method as claimed in claim 13 , wherein the transition metal film includes at least one of a Ta film, a Ti film, a Mo film, a TaN film enriched with Ta, a TiN film enriched with Ti, or a MoN film enriched with Mo.