Method for forming polyatomic layers

• US 6,800,567 B2
• Filed: 08/22/2002
• Issued: 10/05/2004
• Est. Priority Date: 08/27/2001
• Status: Expired due to Fees

• Current Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Original Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Inventors: Cho, Ho Jin
• Primary Examiner(s): Nguyen, Van Thu
• Assistant Examiner(s): Owens, Beth E.
• Application Number:
  US10/226,028
• Publication Number:
  US 20030040197A1
• Time in Patent Office: 775 Days
• Field of Search: 438/758, 438/763, 438/778, 438/785
• US Class Current: 438/763
• CPC Class Codes: H01L 21/02197 the material having a perovskite structure, e.g. BaTiO3
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/31691 with perovskite structure
• CPC Class Codes: H01L 21/318 composed of nitrides

Abstract

A method for forming a polyatomic layer with a mixed deposition method consisting of an atomic layer deposition method (ALD) and a chemical vapor deposition method. The mixed deposition method can be adopted to form a polyatomic high dielectric layer, such as BST or STO. Accordingly, it is possible to form a polyatomic high dielectric layer having a uniform composition distribution, and thereby also having a high dielectric characteristic and a low leakage current characteristic.

Claims

1. A method for forming a polyatomic layer comprising:

forming a first unit layer having a first element of a polyatomic layer using an atomic layer deposition;

forming a second unit layer having a second element of the polyatomic layer using a chemical vapor deposition; and

repeating alternate depositions of the first unit layer and the second unit layer to form the polyatomic layer to a desired thickness.

2. The method as recited in claim 1, wherein the forming of the first unit layer and the second unit layer are carried out at substantially the same temperature.

3. A method for forming a polyatomic layer comprising:

performing a process for a first precursor being absorbed on a substrate in a chamber, wherein the first precursor contains a first element of the polyatomic layer;

purging out the first precursor in the chamber;

supplying a first reaction gas in the chamber and forming a first unit layer by inducing a surface reaction between the first reaction gas and the first precursor on the substrate;

purging out the first reaction gas and a any accessory products in the chamber;

supplying a second precursor and a second reaction gas in the chamber and forming a second unit layer, wherein the second precursor contains a second element of the polyatomic layer, and wherein the second precursor and the second reaction gas react chemically;

purging out the second precursor, the second reaction gas and e any accessory products in the chamber; and

repeating alternate depositions of the first unit layer and the second unit layer to form the polyatomic layer to a desired thickness.

4. The method as recited in claim 3, wherein the forming of the first unit layer and the second unit layer are carried out at substantially the same temperature.

5. The method as recited in claim 3, wherein the first unit layer and the second unit layer are formed at a temperature ranging from about 300°

C. to about 450°

C.

6. The method as recited in claim 3, further comprising performing a rapid thermal process at a temperature ranging from about 500°

C. to about 700°

C. in an ambient of nitrogen for a time period ranging from about 1 minute to about 10 minutes, after forming the first and second unit layers.

7. The method as recited in claim 3, wherein the first precursor comprises a Ba source and a Sr source.

8. The method as recited in claim 7, wherein the second precursor comprises a Ti source.

9. The method as recited in claim 3, wherein the first precursor comprises Sr.

10. The method as recited in claim 7, wherein the first unit layer is a (Ba,Sr)O layer.

11. The method as recited in claim 10, wherein the (Ba,Sr)O layer is formed from Ba(THD)₂-tetraene and Sr(THD)₂-tetraen.

12. The method as recited in claim 10, wherein the second unit layer is a TiO₂ layer.

13. The method as recited in claim 3, wherein the first reaction gas is selected from the group consisting of an O₂ gas, an O₃ gas and plasma produced from N₂O gas.

14. The method as recited in claim 3, wherein the second reaction gas is selected from the group consisting of O₂, a N₂O gas and NH₃.

15. The method as recited in claim 7, wherein Ba source is selected from the group consisting of Ba(THD)₂-tetraene, Ba(THD)₂-triene(Ba(C₁₁H₁₉O₂)—

NH₂((C₂H₄)NH(C₂H₄))₂), Ba(THD)₂-pmdt(Ba(C₁₁H₁₉O₉)₂-/C₉H₂₃N₄), Ba(METHD)₂ and Ba(O₄C₁₄H₂₅)₂.

16. The method as recited in claim 7, wherein the Sr source is selected from the group consisting of Sr(THD)₂-tetraene, Sr(THD)₂-triene(Sr (C₁₁H₁₉O₂)-NH₂((C₂H₄)NH(C₂H₄))₂), Sr(THD)₂-pmdt(Sr(C₁₁H₁₉O₂)₂-C₉H₂₃N₃), Sr(METHD)₂ and Sr(O₄C₁₄H₂₅)₂.

17. The method as recited in claim 8, wherein the Ti source is selected from the group consisting of Ti(O-i-Pr)₄(Ti(OC₃H₇)₄), Ti(MPD)(THD)₂(Ti(O₂C₆H₁₂)(O₂C₁₁H₁₉)₂), and Ti(O-t-BU)₂(THD)₂(Ti(OC₄H₉)₂(C₁₁H₁₉O₂)₂).

18. The method as recited in claim 8, wherein the polyatomic layer is a layer selected from the group consisting of Pb(Zr, Ti)O₃ layer, SrBi₂Ta₂O₉ layer, (Bi_xLa_y)Ti₃O₁₂ layer, TiAlN layer, TiSiN layer, RuTiN layer and RuTaN layer.