Metal oxide protective layer for a semiconductor device

• US 9,384,987 B2
• Filed: 12/15/2014
• Issued: 07/05/2016
• Est. Priority Date: 04/04/2012
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM IP Holding B.V. (ASM International NV)
• Inventors: Jung, Sung-Hoon
• Primary Examiner(s): SHOOK, DANIEL P
• Application Number:
  US14/571,126
• Publication Number:
  US 20150147877A1
• Time in Patent Office: 568 Days
• Field of Search: 438/763, 257/411
• US Class Current: 1/1
• CPC Class Codes: C23C 16/405 of refractory metals or yttrium
• CPC Class Codes: C23C 16/409 of the type ABO3 with A representing alkali, alkaline earth metal or lead and B representing a refractory metal, nickel, scandium or a lanthanide
• CPC Class Codes: C23C 16/45527 characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations
• CPC Class Codes: H01L 21/02186 the material containing titanium, e.g. TiO2
• CPC Class Codes: H01L 21/02197 the material having a perovskite structure, e.g. BaTiO3
• CPC Class Codes: H01L 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02362 formation of intermediate layers, e.g. capping layers or diffusion barriers
• CPC Class Codes: H01L 21/28194 by deposition, e.g. evaporation, ALD, CVD, sputtering, laser deposition H01L21/28202 takes precedence
• CPC Class Codes: H01L 21/28229 by deposition of a layer, e.g. metal, metal compound or poysilicon, followed by transformation thereof into an insulating layer
• CPC Class Codes: H01L 29/513 the variation being perpendicular to the channel plane
• CPC Class Codes: H01L 29/517 the insulating material comprising a metallic compound, e.g. metal oxide, metal silicate H01L29/518 takes precedence

Abstract

Embodiments related to metal oxide protective layers formed on a surface of a halogen-sensitive metal-including layer present on a substrate processed in a semiconductor processing reactor are provided. In one example, a method for forming a metal oxide protective layer is provided. The example method includes forming a metal-including active species on the halogen-sensitive metal-including layer, the metal-including active species being derived from a non-halogenated metal oxide precursor. The example method also includes reacting an oxygen-containing reactant with the metal-including active species to form the metal oxide protective layer.

Claims

1. A method of forming a metal oxide protective layer on a surface of a halogen-sensitive metal-including layer present on a substrate processed in a semiconductor processing reactor, the method comprising the steps of:

providing a halogen-sensitive metal-including layer present on a substrate;

forming a metal oxide protective layer overlying the halogen-sensitive metal-including layer, the metal oxide protective layer derived from a non-halogenated metal oxide precursor; and

forming a high-k dielectric metal-including film overlaying the metal oxide protective layer by exposing the metal oxide protective layer to a halogen-including metal compound.

2. The method of claim 1, wherein the step of forming a metal oxide protective layer comprises using at least a portion of a surface of the halogen-sensitive metal-including layer.

3. The method of claim 1, wherein the step of forming a metal oxide protective layer comprises reacting an oxygen-containing reactant with an active species of the metal-including layer.

4. The method of claim 1, wherein the metal oxide protective layer is a barrier layer.

5. The method of claim 1, wherein the metal oxide protective layer is a buffer layer.

6. The method of claim 1, where the halogen-sensitive metal-including layer is sensitive to chlorine and where the non-halogenated metal oxide precursor comprises a non-chlorinated metal oxide precursor.

7. The method of claim 1, wherein the halogen-sensitive metal-including layer comprises an alkaline earth metal-including oxide.

8. The method of claim 1, wherein the halogen-sensitive metal-including layer comprise one or more of SrTi_xO_y, BaTi_xO_y, SrO, and Sr_xBa(_1-x).

9. The method of claim 1, wherein the metal oxide protective layer excludes alkaline earth metals.

10. The method of claim 1, wherein the metal oxide protective layer comprises titanium oxide.

11. The method of claim 1, wherein the metal oxide protective layer comprises aluminum oxide.

12. A method of fabricating a semiconductor device, the method comprising the steps of:

forming a halogen-sensitive high-K dielectric material on a substrate;

forming a metal oxide protective layer on the halogen-sensitive high-K dielectric material; and

forming a high-k dielectric metal-including film overlying the metal oxide protective layer by exposing the metal oxide protective layer to a halogen-including metal compound.

13. The method of claim 12, wherein a pressure during the step of forming a metal oxide protective layer is ranges from 0.1 Torr to 10 Torr.

14. The method of claim 12, wherein a temperature during the step of forming a metal oxide protective layer is ranges from 100°

C. to 400°

C.

15. The method of claim 12, wherein the step of forming a metal oxide protective layer comprises using a precursor selected from the group consisting of:

titanium tetraethoxide (Ti(OC₂H₅)₄), titanium tetramethoxide (Ti(OCH₃)₄), titanium tetraisopropoxide (Ti(i-OC₃H₇)₄, and titanium tetra-n-butoxide (Ti(n-OC₄H₉)₄));

transition metal amino complexes (e.g., tetrakis(dimethylamido)titanium (Ti(N(CH₃)₂)₄) and tetrakis(diethylamido)titanium (Ti(N(C₂H₅)₂)₄));

transition metal silanes (e.g., tetrakis(trimethylsilylmethyl)titanium (Ti((CH₃)SiCH₂)₄)); and

transition metal cyclopentadiene complexes (e.g., (η

8-cyclooctatetraene)(η

5-cyclopentadienyetitanium (C₁₃H₁₃Ti), di-1,3-cyclopentadien-1-yl [bis(N-methylmethanaminato)]titanium (C₁₄H₂₂N₂Ti), and dicyclopentadienyl titanium diazide (C₁₀H₁₀N₆Ti).

16. The method of claim 12, wherein the step of forming a metal oxide protective layer comprises using a precursor selected from the group consisting of:

aluminum alkyl complexes, aluminum alkoxides, aluminum silanes, aluminum amino complexes, and aluminum cyclopentadiene complexes.

17. A method of forming a metal oxide protective layer on a surface of a halogen-sensitive metal-including layer present on a substrate processed in a semiconductor processing reactor, the method comprising the steps of:

providing a halogen-sensitive metal-including layer present on a substrate;

using atomic layer deposition, forming a metal oxide protective layer overlying the halogen-sensitive metal-including layer, the metal oxide protective layer derived from a non-halogenated metal oxide precursor; and

forming a high-k dielectric metal-including film comprising residual halogen atoms overlying the metal oxide protective layer.

18. The method of claim 17, wherein the film comprising residual halogen atoms comprises a transition metal compound.

19. The method of claim 17, wherein the halogen-sensitive high-K dielectric material comprises an alkaline earth metal-including metal.

20. The method of claim 17, wherein the metal oxide protective layer has a thickness of 20 Å

or less.